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Al-Quhaiti MAA, Abdul-Ghani R, Mahdy MAK, Assada MA. Malaria among under-five children in rural communities of Al-Mahweet governorate, Yemen. Malar J 2022; 21:344. [PMID: 36401272 PMCID: PMC9675118 DOI: 10.1186/s12936-022-04371-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 11/07/2022] [Indexed: 11/19/2022] Open
Abstract
Background Malaria burden among under-five children living in endemic areas of Yemen is largely unknown due to the lack of community-based studies. Therefore, this study determined the prevalence and risk factors associated with falciparum malaria among under-five children in rural communities of Al-Mahweet governorate, Yemen. Methods This community-based, cross-sectional study recruited 400 under-five children from two rural districts of Al-Mahweet governorate in December 2019. Demographic characteristics (gender, age, education and occupation of the child’s parents, and household size) and risk factors associated with malaria were collected through interviews with children’s caregivers using a structured questionnaire. Finger-prick blood was screened for Plasmodium falciparum and non-falciparum species using rapid diagnostic tests (RDTs), and duplicate Giemsa-stained thick and thin blood films were examined for malaria parasites. The density of asexual P. falciparum stages was also estimated. Data were then analysed, and the agreement between the results of thick-film microscopy and RDTs for diagnosing falciparum malaria was assessed using the kappa index. Statistical significance was set at a P-value of < 0.05. Results Plasmodium falciparum was prevalent among 9.8% (95% CI 7.0–13.1) of under-five children in the rural communities of Al-Mahweet, with a median asexual parasite density of 763 ± 2606 parasites/μl of blood (range: 132–4280) and low-to-moderate parasitaemia levels. Approximately one-third of microscopy-confirmed cases were gametocyte carriers. Multivariable logistic regression analysis confirmed that age of three years or older (AOR = 5.6, 95% CI 1.6–19.8; P = 0.007), not sleeping under a mosquito net the previous night of the survey (AOR = 8.0, 95% CI 2.4–27.4; P = 0.001), sleeping outdoors at night (AOR = 4.4, 95% CI 2.0–10.0; P < 0.001), and absence of indoor residual spraying (IRS) during the last year (AOR = 4.2, 95% CI 1.9–9.4; P < 0.001) were the independent predictors of falciparum malaria among under-five children in the rural communities of Al-Mahweet. The observed percentage agreement between thick-film microscopy and RDTs was 98.5%, with a very good agreement (k-index = 0.9) between the two methods for falciparum malaria diagnosis that was statistically significant. Conclusion Approximately one in ten under-five children in rural communities of Al-Mahweet is infected with P. falciparum based on microscopy and RDTs. Age of three years or older, not sleeping under mosquito nets, sleeping outdoors at night and absence of IRS can independently predict falciparum malaria among them. The very good agreement between thick-film microscopy and RDTs for diagnosing falciparum malaria in children supports the usefulness of using RDTs in such resource-limited rural communities.
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Al-Murisi WMS, Al-Mekhlafi AM, Mahdy MAK, Al-Haidari SA, Annuzaili DA, Thabit AAQ. Schistosoma mansoni and soil-transmitted helminths among schoolchildren in An-Nadirah District, Ibb Governorate, Yemen after a decade of preventive chemotherapy. PLoS One 2022; 17:e0273503. [PMID: 36006980 PMCID: PMC9409567 DOI: 10.1371/journal.pone.0273503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 08/09/2022] [Indexed: 11/19/2022] Open
Abstract
The Ministry of Public Health in Yemen continues the implementation of school and community–based preventive chemotherapy with praziquantel and albendazole for the control and elimination of schistosomiasis and soil-transmitted helminths (STH). The latest remapping to update the distribution of schistosomiasis and STH was conducted seven years ago. This study aimed to estimate the prevalence, intensity and associated risk factors of Schistosoma mansoni and STH among schoolchildren in An-Nadirah District, Ibb Governorate, Yemen. A cross-sectional study was carried out among schoolchildren aged 6–15 years in four selected schools. Biological, demographic, socioeconomic and environmental data were collected using a pre-tested questionnaire. S. mansoni and STH eggs were detected and counted by the microscopic examination of Kato-Katz fecal smears. Out of 417 schoolchildren, 17.0% were infected with at least one intestinal helminth. Prevalence of S. mansoni and STH were 6.5% and 9.1%, respectively. The most prevalent parasite among STH was Ascaris lumbricoides (8.4%). Unemployed fathers (Adjusted Odds Ratio (AOR) = 3.2; 95% Confidence interval (CI): 1.23, 8.52; P = 0.018), eating exposed food (AOR: 2.9; 95%CI = 1.24, 6.89; P = 0.014), not washing hands before eating and after defecation (AOR: 4.8; 95%CI = 1.77, 12.81; P = 0.002), and schools located close to water stream (AOR: 22.1; 95%CI = 5.12, 95.46; P <0.001) were independent risk factors of ascariasis. Swimming in ponds/stream (AOR: 3.9; 95%CI = 1.63, 9.55; P = 0.002), and schools close to the stream (AOR: 24.7; 95%CI = 3.05, 200.07; P = 0.003) were independent risk factors of intestinal schistosomiasis. The present study does not indicate a reduction in the prevalence of intestinal schistosomiasis in this rural area since the latest remapping conducted in 2014, although ascariasis was reduced by half. The prevalence of the two parasites was highly focal in areas close to the valley, suggesting a significant role of the stream in sustaining and accelerating the parasitic infection. Children practicing swimming and having poor hygienic practices were at high exposure to S. mansoni and A. lumbricoides, respectively. Water, Sanitation and Hygiene intervention, school–based health education, and snail control, in addition to mass drug administration, will help in the interruption of transmission of schistosomiasis and STH.
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Affiliation(s)
| | | | - Mohammed A. K. Mahdy
- Department of Parasitology, Faculty of Medicine, Sana’a University, Sana’a, Yemen
- Tropical Disease Research Center, Faculty of Medicine, University of Science and Technology, Sana’a, Yemen
- * E-mail:
| | - Sami Ahmed Al-Haidari
- Diseases Control & Surveillance, Ministry of Public Health and Population, Sana’a, Yemen
| | - Dhekra A. Annuzaili
- Primary Health Care Department, Ministry of Public Health and Population, Aden, Yemen
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Al-Haidari SA, Mahdy MAK, Al-Mekhlafi AM, Al Murisi WMS, Thabit AAQ, Al-Amad MA, Al-Shamahi H, Bahashwan OS, Al Serouri A. Intestinal schistosomiasis among schoolchildren in Sana'a Governorate, Yemen: Prevalence, associated factors and its effect on nutritional status and anemia. PLoS Negl Trop Dis 2021; 15:e0009757. [PMID: 34547034 PMCID: PMC8454980 DOI: 10.1371/journal.pntd.0009757] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 08/24/2021] [Indexed: 11/18/2022] Open
Abstract
Intestinal schistosomiasis is a neglected tropical disease, causing morbidity and mortality in tropical and subtropical countries. Despite the frequent implementation of mass drug administration with praziquantel, the reinfection with Schistosoma mansoni is still common in Yemen. In addition, there is a scarcity of information on the impact of S. mansoni on nutritional status and anemia among schoolchildren. The present study aimed to determine prevalence and risk factors of intestinal schistosomiasis and investigate its impact on nutritional status and anemia among schoolchildren in Sana’a Governorate, Yemen. It was conducted in 2018 on 445 schoolchildren aged 5–15 years. Biodata, socio-economic, demographic, behavioral and environmental data were collected using a standard questionnaire. S. mansoni was identified and quantified by microscopic examination of Kato-Katz fecal smear. Hemoglobin concentration and anthropometric measurements were estimated using standard methods. The prevalence of S. mansoni was higher in Al-Haimah Al-Dakheliah (33.9%) than Bani Mater (1.4%). Household without tap water (Adjusted Odds Ratio (AOR) = 2.9, 95% Confidence interval (CI): 1.12, 7.55, P = 0.028) was the independent risk factor of the infection. The prevalence of wasting and stunting was 25.0% (95%CI: 21.2%, 29.2%) and 45.8% (95%CI: 41.2%, 50.5%), respectively. The prevalence of underweight among schoolchildren aged 5–10 years was 27.3% (95%CI: 21.9%, 33.4%). The prevalence of anemia was 31.7% (95%CI: 27.5%, 36.2%) with 0.5%, 21.1% and 10.1% being severe, moderate and mild anemia, respectively. S. mansoni (AOR = 4.1, 95%CI: 2.16, 7.84, P < 0.001) and early adolescence (AOR = 6.8, 95%CI: 4.26, 10.82, P < 0.001) were independent predictors of stunting among schoolchildren. The early adolescent schoolchildren (AOR = 3.1, 95%CI: 1.86, 4.97, P < 0.001) and children from families with low (AOR = 2.1, 95%CI: 1.01, 4.15, P = 0.046) or moderate wealth (AOR = 2.3, 95%CI: 1.11, 4.77, P = 0.026) were significantly more wasted. Early adolescence (AOR = 1.8, 95%CI:1.14, 2.78, P = 0.011), female (AOR = 1.6, 95%CI: 1.03, 2.43, P = 0.038) and Al-Haimah Al-Dakheliah District (AOR = 3.4, 95%CI: 1.20, 9.55, P = 0.021) were independent risk factors for anemia. The study findings indicate highly focal prevalence of schistosomiasis in Sana’a Governorate with a public health significance that varies from low to high risk. Approximately half of schoolchildren were stunted, which was associated with S. mansoni infection and early adolescence. One quarter of schoolchildren were wasted with early adolescent schoolchildren and children from poor families being at high risk of wasting. Anemia was a moderate public health threat affecting the female and the early adolescent schoolchildren. The study suggests the implementation of control measures to combat schistosomiasis and integrated diseases control programmes to improve the health status of schoolchildren in Sana’a Governorate. The present study aimed to determine prevalence and risk factors of intestinal schistosomiasis and investigate its impact on nutritional status and anemia among schoolchildren in Sana’a Governorate, Yemen. It was conducted in 2018 on 445 schoolchildren aged 5–15 years. Information was collected using a standard questionnaire. S. mansoni was identified by microscopic examination of Kato-Katz fecal smear. Hemoglobin concentration and anthropometric measurements were estimated using standard methods. The prevalence of S. mansoni was highly focal (1.4–33.9%). Schoolchildren living in households without tap water had significantly high infection rate of S. mansoni. The prevalence of wasting, stunting, underweight and anemia among schoolchildren was 25.0%, 45.8%, 27.3% and 31.7%, respectively. Although S. mansoni was significantly associated with stunting, no significant association was found between S. mansoni and wasting, underweight or anemia. The stunting was higher among early adolescent than young schoolchildren. The early adolescent schoolchildren and children from families with low or moderate wealth were significantly more wasted than schoolchildren from families with high wealth. Schoolchildren in the early adolescence, being female or living in Al-Haimah Al-Dakheliah District were at high risk of anemia. The study suggests implementation of control measures to combat schistosomiasis and integrated diseases control programmes to improve the health status of schoolchildren in Sana’a Governorate.
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Affiliation(s)
- Sami Ahmed Al-Haidari
- Department of Parasitology, Faculty of Medicine, Sana’a University, Sana’a, Yemen
- Diseases Control & Surveillance, Ministry of Public Health and Population, Sana’a, Yemen
| | - Mohammed A. K. Mahdy
- Department of Parasitology, Faculty of Medicine, Sana’a University, Sana’a, Yemen
- * E-mail:
| | | | | | | | | | - Hassan Al-Shamahi
- Department of Medical Microbiology, Faculty of Medicine, Sana’a University, Sana’a, Yemen
| | - Othman Saeed Bahashwan
- Field Epidemiology Training Programme, Ministry of Public Health and Population, Sana’a, Yemen
| | - Abdulwahed Al Serouri
- Field Epidemiology Training Programme, Ministry of Public Health and Population, Sana’a, Yemen
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Abdul-Ghani R, Fouque F, Mahdy MAK, Zhong Q, Al-Eryani SMA, Alkwri A, Beier JC. Multisectoral Approach to Address Chikungunya Outbreaks Driven by Human Mobility: A Systematic Review and Meta-Analysis. J Infect Dis 2021; 222:S709-S716. [PMID: 33119099 PMCID: PMC7594244 DOI: 10.1093/infdis/jiaa500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The role of human mobility in the epidemiology of emerging Aedes-transmitted viral diseases is recognized but not fully understood. The objective of this systematic review and meta-analysis was to examine how human mobility patterns are driving chikungunya outbreaks. METHODS Literature was systematically reviewed for studies on chikungunya prevalence in countries/territories with high-level evidence of human mobility-driven outbreaks, based on: (1) emergence of chikungunya outbreaks with epidemic chikungunya virus genotypes among displaced/migrant populations and their hosting communities; and (2) identification of imported index case(s) with epidemic genotypes phylogenetically related to the genotypes circulating during emerging or subsequent outbreaks. RESULTS The meta-analysis of extracted prevalence data revealed that a large proportion of the population in countries/territories afflicted by outbreaks is still at risk of infection during future outbreaks. On the other hand, approximately one-half of suspected chikungunya cases could be infected with other co-circulating acute febrile illnesses. CONCLUSIONS We discussed in this paper how human mobility-driven chikungunya outbreaks can be addressed, and how the involvement of several sectors in addition to the health sector in multisectoral approaches (MSAs) is important for prevention and control of chikungunya and other Aedes-transmitted arboviral outbreaks.
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Affiliation(s)
- Rashad Abdul-Ghani
- Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.,Tropical Disease Research Center, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana'a, Yemen
| | - Florence Fouque
- UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland
| | - Mohammed A K Mahdy
- Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.,Tropical Disease Research Center, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana'a, Yemen
| | - Qingxia Zhong
- UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland
| | - Samira M A Al-Eryani
- Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Abdulsamad Alkwri
- Integrated Vector Management Unit, National Malaria Control Programme, Ministry of Public Health and Population, Sana'a, Yemen
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, Florida, USA
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Abdul-Aziz M, Mahdy MAK, Abdul-Ghani R, Alhilali NA, Al-Mujahed LKA, Alabsi SA, Al-Shawish FAM, Alsarari NJM, Bamashmos W, Abdulwali SJH, Al Karawani M, Almikhlafy AA. Bacterial vaginosis, vulvovaginal candidiasis and trichomonal vaginitis among reproductive-aged women seeking primary healthcare in Sana'a city, Yemen. BMC Infect Dis 2019; 19:879. [PMID: 31640583 PMCID: PMC6805389 DOI: 10.1186/s12879-019-4549-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/09/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND In Yemen, the underlying causes of infectious vaginitis have been neglected. Therefore, this study aimed to determine the prevalence and risk factors associated with bacterial vaginosis (BV), vulvovaginal candidiasis (VVC) and trichomonal vaginitis (TV) among non-pregnant reproductive-aged women. METHODS A cross-sectional study was conducted among 347 non-pregnant reproductive-aged women seeking primary healthcare in Sana'a city, Yemen. Data about sociodemographic characteristics, lifestyle-related behaviors, routine hygienic practices, menstrual care and history and type of contraceptive intake were collected using a structured questionnaire. Vaginal discharge samples were collected and examined for discharge characteristics and pH by a gynecologist. Then, samples were examined for BV, VVC and TV. Data were analyzed using suitable statistical tests. RESULTS Vaginal infections were prevalent among 37.6% of reproductive-aged women, where BV was the most prevalent (27.2%). VVC was significantly higher among symptomatic women and significantly associated with itching (P = 0.005). Using bivariate analysis, the age of < 25 years (odds ratio [OR] = 1.9, 95% confidence interval [CI]: 1.16-3.10; P = 0.010) and using intrauterine contraceptive devices (IUCDs) (OR = 1.8, 95% CI: 1.09-2.89; P = 0.020) were significantly associated with BV, while history of miscarriage was significantly associated with a lower risk of BV (OR = 0.5, 95% CI: 0.31-0.85, P = 0.009). However, polygyny was significantly associated with VVC (OR = 3.4, 95% CI: 1.33-8.66; P = 0.007). Multivariable analysis confirmed that age of < 25 years and using IUCD were the independent predictors of BV, while history of miscarriage was an independent protective factor against BV. On the other hand, marriage to a polygamous husband was the independent predictor of VVC. CONCLUSIONS More than a third of non-pregnant reproductive-aged women seeking PHC in Sana'a have single or mixed infections with BV, VVC or TV. BV is the most frequent cause of vaginitis and is significantly associated with the age of < 25 years and using IUCDs, while VVC is significantly higher among women with polygamous husbands. Health education of polygamous husbands and their wives, regular monitoring of BV among IUCD users and screening women for vaginitis before treatment are recommended.
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Affiliation(s)
- Maha Abdul-Aziz
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Mohammed A K Mahdy
- Tropical Disease Research Center, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen. .,Department of Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen.
| | - Rashad Abdul-Ghani
- Tropical Disease Research Center, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen.,Department of Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Nuha A Alhilali
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Leena K A Al-Mujahed
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Salma A Alabsi
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Fatima A M Al-Shawish
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Noura J M Alsarari
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Wala Bamashmos
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Shahad J H Abdulwali
- Medical Laboratory Sciences Program, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Mahdi Al Karawani
- Department of Community Medicine, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Abdullah A Almikhlafy
- Department of Community Medicine, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
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Abdul-Ghani R, Mahdy MAK, Al-Eryani SMA, Fouque F, Lenhart AE, Alkwri A, Al-Mikhlafi AM, Wilke ABB, Thabet AAQ, Beier JC. Impact of population displacement and forced movements on the transmission and outbreaks of Aedes-borne viral diseases: Dengue as a model. Acta Trop 2019; 197:105066. [PMID: 31226251 DOI: 10.1016/j.actatropica.2019.105066] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 05/31/2019] [Accepted: 06/17/2019] [Indexed: 01/06/2023]
Abstract
Population displacement and other forced movement patterns following natural disasters, armed conflicts or due to socioeconomic reasons contribute to the global emergence of Aedes-borne viral disease epidemics. In particular, dengue epidemiology is critically affected by situations of displacement and forced movement patterns, particularly within and across borders. In this respect, waves of human movements have been a major driver for the changing epidemiology and outbreaks of the disease on local, regional and global scales. Both emerging dengue autochthonous transmission and outbreaks in countries known to be non-endemic and co-circulation and hyperendemicity with multiple dengue virus serotypes have led to the emergence of severe disease forms such as dengue hemorrhagic fever and dengue shock syndrome. This paper reviews the emergence of dengue outbreaks driven by population displacement and forced movements following natural disasters and conflicts within the context of regional and sub-regional groupings.
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Affiliation(s)
- Rashad Abdul-Ghani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen; Tropical Disease Research Center, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana'a, Yemen.
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen; Tropical Disease Research Center, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana'a, Yemen
| | - Samira M A Al-Eryani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Florence Fouque
- UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization, Geneva, Switzerland
| | - Audrey E Lenhart
- Center for Global Health/Division of Parasitic Diseases and Malaria/Entomology Branch, U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Abdulsamad Alkwri
- Integrated Vector Management Unit, National Malaria Control Programme, Ministry of Public Health and Population, Sana'a, Yemen
| | - Abdulsalam M Al-Mikhlafi
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - André B B Wilke
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Ahmed A Q Thabet
- Neglected Tropical Diseases and Pandemic Influenza Preparedness Department, WHO Office, Sana'a, Yemen
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
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Alghazali KA, Teoh BT, Loong SK, Sam SS, Che-Mat-Seri NAA, Samsudin NI, Yaacob CN, Azizan NS, Oo A, Baharudin NA, Tan KK, Abd-Jamil J, Nor'e SS, Khor CS, Johari J, Mahdy MAK, AbuBakar S. Dengue Outbreak during Ongoing Civil War, Taiz, Yemen. Emerg Infect Dis 2019; 25:1397-1400. [PMID: 30924766 PMCID: PMC6590741 DOI: 10.3201/eid2507.180046] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
We identified dengue in ≈51% of patients given a clinical diagnosis of suspected dengue in Taiz, Yemen, during 2016. The cosmopolitan genotype of dengue virus type 2 was most common; viruses appeared to have originated in Saudi Arabia. Damage to public health infrastructure during the ongoing civil war might enable dengue to become endemic to Yemen.
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Mahdy MAK, Abdul-Ghani R, Abdulrahman TAA, Al-Eryani SMA, Al-Mekhlafi AM, Alhaidari SAA, Azazy AA. Onchocerca volvulus infection in Tihama region - west of Yemen: Continuing transmission in ivermectin-targeted endemic foci and unveiled endemicity in districts with previously unknown status. PLoS Negl Trop Dis 2018; 12:e0006329. [PMID: 29505580 PMCID: PMC5854432 DOI: 10.1371/journal.pntd.0006329] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 03/15/2018] [Accepted: 02/20/2018] [Indexed: 11/29/2022] Open
Abstract
Background Onchocerciasis in Yemen is one of the most neglected diseases, where baseline estimates of onchocerciasis and monitoring of the impact of ivermectin regularly administered to the affected individuals on its transmission are lacking. Therefore, this study aimed to determine the anti-Ov16 IgG4 seroprevalence among local communities of Hodeidah and Al-Mahwit governorates of Tihama region. The factors possibly associated with previous exposure to infection were also studied. Methodology/Principal findings This cross-sectional study was conducted in two ivermectin-targeted districts endemic for onchocerciasis in Hodeidah and Al-Mahwit and two untargeted districts with unknown previous endemicity in Hodeidah between February and July 2017. For 508 residents sampled by a multi-stage random approach, data were collected and blood specimens were screened for anti-Ov16 IgG4 using the SD BIOLINE Onchocerciasis IgG4 rapid tests. The study revealed an overall anti-Ov16 IgG4 rate of 18.5% (94/508) in all surveyed districts, with 10.2% (12/118) of children aged ≤10 years being seropositive. Moreover, rates of 8.0% (4/50) and 6.1% (4/66) were found in districts not officially listed as endemic for the disease. Multivariable analysis confirmed the age of more than ten years and residing within a large family as the independent predictors of exposure to infection. Conclusions/Significance Onchocerciasis transmission is still ongoing as supported by the higher anti-Ov16 IgG4 seroprevalence rate among children aged ≤10 years compared to that (<0.1%) previously set by the World Health Organization as a serologic criterion for transmission interruption. Further large-scale studies combining serologic and entomologic criteria are recommended for the mapping of O. volvulus in human and blackfly populations in endemic foci and their neighboring areas of uncertain endemicity. In addition, ivermectin distribution, coverage and impact on disease transmission need to be continually assessed. Onchocerciasis is endemic in certain foci in the western governorates of Yemen. Monitoring the impact of the regular ivermectin administration to affected individuals on the transmission status and providing baseline onchocerciasis estimates in endemic areas are crucial for planning effective elimination strategies. We found that the disease transmission is still ongoing in Hodeidah and Al-Mahwit governorates of Tihama region as indicated by the anti-Ov16 IgG4 seropositivity among children aged ≤10 years. In Bani Sa'ad, where affected individuals had been regularly targeted with ivermectin over the last 15 years, we found that the anti-Ov16 IgG4 seroprevalence rate was significantly lower among children aged ≤10 years (9.1%; 5/55) compared to those >10 years (24.5%; 37/151), reflecting a possible decline in disease transmission. We also revealed onchocerciasis transmission in districts with unknown previous endemicity for the first time, with rates of 8.0% and 6.1% being found in Al Marawi'ah and As Sukhnah districts of Hodeidah. Large-scale surveys are recommended for mapping of O. volvulus in human and blackfly populations in endemic foci and neighboring untargeted areas of uncertain endemicity as a forward step towards the elimination of the disease from the country.
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Affiliation(s)
- Mohammed A. K. Mahdy
- Tropical Disease Research Center, University of Science and Technology, Sana’a, Yemen
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
- * E-mail:
| | - Rashad Abdul-Ghani
- Tropical Disease Research Center, University of Science and Technology, Sana’a, Yemen
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | | | - Samira M. A. Al-Eryani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Abdulsalam M. Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Sami A. A. Alhaidari
- National Schistosomiasis and Parasites Control Program, Ministry of Public Health and Population, Sana’a, Yemen
| | - Ahmed A. Azazy
- Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Al-Baha University, Al-Baha, KSA
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9
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Lee SC, Ngui R, Tan TK, Roslan MA, Ithoi I, Mahdy MAK, Hakim S L, Lim YAL. Understanding Giardia infections among rural communities using the one health approach. Acta Trop 2017; 176:349-354. [PMID: 28859958 DOI: 10.1016/j.actatropica.2017.08.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/19/2017] [Accepted: 08/26/2017] [Indexed: 01/13/2023]
Abstract
The epidemiology of giardiasis in rural villages in Peninsular Malaysia was examined in the context of the One Health triad that encompasses humans, animals and environment (i.e. river water). A cross-sectional study was carried out among five rural communities in Malaysia to determine the prevalence of Giardia duodenalis in humans, animals and river water. Fecal samples collected from humans and animals were examined by light microscopy. Water was sampled from the rivers adjacent to the target communities and investigated for the occurrence of Giardia cysts. The isolated cysts were further genotyped targeting the glutamate dehydrogenase and triosephosphate isomerase genes. The overall prevalence of G. duodenalis was 6.7% (18/269) and 4.7% (8/169) among humans and animals, respectively. Giardia cysts (mean concentration range: 0.10-5.97 cysts/L) were also found in adjacent rivers at four out of the five villages examined. At Kemensah and Kuala Pangsun, Giardia cysts were isolated from humans [rate: 3.7% each (of 54 each)], animals [rates: 6.3% (of 62) and 11.3% (of 16), respectively] and river water [average concentration of 9 samples each: 0.83±0.81 and 5.97±7.00, respectively]. For both villages at Pos Piah and Paya Lebar, 12.2% (of 98) and 6.1% (of 33) of collected human samples were infected, respectively whilst none of the collected animals samples in these villages were found to be positive. The river water samples of these two villages were also contaminated (average concentration: 0.20±0.35 (of 9) and 0.10±0.19 (of 3), respectively). In conclusion, Giardia cysts were simultaneously observed in the human-animal-environment (i.e., river water) interfaces in at least two of five studied communities highlighting a vital need to improve understanding on the interplay of transmission dynamics, the role of infected humans and animals in contaminating the water sources and the role of water as a vehicle of disease transmission in these communities. Indeed, this study illustrates the One Health approach which is to recognize that the optimal health of humans are interconnected with the well-being of animals and their environment.
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Affiliation(s)
- Soo Ching Lee
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Centre of Excellence for Research in AIDS (CERIA), University of Malaya, Kuala Lumpur, Malaysia.
| | - Romano Ngui
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Tiong Kai Tan
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Biodiversity Research Center, Academia Sinica, 115 Taipei, Taiwan
| | - Muhammad Aidil Roslan
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Init Ithoi
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Mohammed A K Mahdy
- Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen
| | - Lokman Hakim S
- Ministry of Health, Block E7, Parcel E, Federal Government Administration Centre, 62590 Putrajaya, Malaysia; Department of Community Medicine, School of Medicine, International Medical University, Bukit Jalil, 57000 Kuala Lumpur, Malaysia
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia; Centre of Excellence for Research in AIDS (CERIA), University of Malaya, Kuala Lumpur, Malaysia.
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10
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Mahdy MAK, Alareqi LMQ, Abdul-Ghani R, Al-Eryani SMA, Al-Mikhlafy AA, Al-Mekhlafi AM, Alkarshy F, Mahmud R. A community-based survey of Toxoplasma gondii infection among pregnant women in rural areas of Taiz governorate, Yemen: the risk of waterborne transmission. Infect Dis Poverty 2017; 6:26. [PMID: 28190399 PMCID: PMC5304399 DOI: 10.1186/s40249-017-0243-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 01/13/2017] [Indexed: 11/10/2022] Open
Abstract
Background Toxoplasma gondii is a zoonotic coccidian parasite causing morbidity and mortality. In Yemen, T. gondii infection has been reported among pregnant women seeking healthcare in the main cities. However, no data are available on the prevalence of T. gondii infection and its associated risk factors among pregnant women in the rural communities of the country. Thus, the present study aimed to determine the seroprevalence of T. gondii and identify its risk factors among pregnant women in the rural communities of Taiz governorate, Yemen. Methods A total of 359 pregnant women living in the rural communities of Taiz governorate were enrolled in this study by house-to-house visits. Data were collected using a pre-designed questionnaire, and blood samples were collected and tested for the detection of anti- T. gondii IgM and IgG antibodies by enzyme-linked immunosorbent assay. Results The prevalence of T. gondii infection among pregnant women in this study was 46.2% (166/359). Bivariate analysis identified the age of ≥ 30 years (odds ratio [OR] = 1.7; 95% confidence interval [CI] = 1.09–2.65, P = 0.019) and unimproved water sources (OR = 2.2; 95% CI = 1.10–4.55, P = 0.023) as factors associated with T. gondii infection among pregnant women. The multivariable analysis, however, identified unimproved water sources as an independent risk factor (adjusted OR = 2.4; 95% CI = 1.16–5.0, P = 0.018) associated with T. gondii infection among pregnant women. Conclusions Pregnant women in the rural communities of Taiz, Yemen are at high risk of contracting T. gondii infection. Unimproved water sources (wells, water streams and water tanks) are significantly associated with T. gondii infection and should be considered in prevention and control strategies, especially among pregnant women. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0243-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mohammed A K Mahdy
- Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen. .,Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.
| | - Lina M Q Alareqi
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Rashad Abdul-Ghani
- Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen.,Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Samira M A Al-Eryani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Abdullah A Al-Mikhlafy
- Department of Community Medicine, Faculty of Medicine, University of Science and Technology, Sana'a, Yemen
| | - Abdulsalam M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Fawzya Alkarshy
- Yemeni-Swedish Hospital, Ministry of Public Health and Population, Taiz, Yemen
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
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11
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Abdul-Ghani R, Mahdy MAK, Beier JC, Basco LK. Hidden reservoir of resistant parasites: the missing link in the elimination of falciparum malaria. Infect Dis Poverty 2017; 6:12. [PMID: 28166813 PMCID: PMC5294824 DOI: 10.1186/s40249-016-0227-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 12/20/2016] [Indexed: 11/29/2022] Open
Abstract
Background To successfully eliminate malaria, an integrated system that includes a number of approaches and interventions—aimed at overcoming the threat of antimalarial drug resistance—is required. Significant progress has been made in reducing malaria incidence through large-scale use of artemisinin-based combination therapies and insecticide-treated nets. To consolidate these gains, attention should be paid to the missing links in the elimination of malaria. One of these gaps is the residual reservoir of submicroscopic resistant parasites, which remains after case management or other control measures have been carried out. Therefore, the present opinion piece highlights the importance of exploring the role that submicroscopic resistant parasites could play in hindering malaria elimination by allowing the persistence of transmission, particularly in areas of low transmission or in the pre-elimination and/or elimination phase. Discussion If malaria elimination interventions are to be effective, the relative role of the hidden reservoir of resistant parasites needs to be assessed, particularly in regions that are low-transmission settings and/or in pre-elimination and/or elimination phases. Various ongoing studies are focusing on the role of submicroscopic malaria infections in malaria transmission but overlook the possible build-up of resistance to antimalarial drugs among submicroscopic parasite populations. This is an important factor as it may eventually limit the effectiveness of malaria elimination strategies. Conclusions An evidence-based estimation of the “true” reservoir of resistant parasites can help target the existing and emerging foci of resistant parasites before they spread. Emergence and spread of artemisinin-resistant Plasmodium falciparum malaria in Southeast Asia underline the need to contain drug resistance. Electronic supplementary material The online version of this article (doi:10.1186/s40249-016-0227-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rashad Abdul-Ghani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen. .,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen.
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Leonardo K Basco
- Unité de Recherche 198, Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Institut de Recherche pour le Développement, Faculté de Médecine La Timone, Aix-Marseille Université, Marseille, France
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12
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Alyousefi TAA, Abdul-Ghani R, Mahdy MAK, Al-Eryani SMA, Al-Mekhlafi AM, Raja YA, Shah SA, Beier JC. A household-based survey of knowledge, attitudes and practices towards dengue fever among local urban communities in Taiz Governorate, Yemen. BMC Infect Dis 2016; 16:543. [PMID: 27717333 PMCID: PMC5054547 DOI: 10.1186/s12879-016-1895-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 10/01/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Yemen has witnessed several dengue fever outbreaks coincident with the social unrest and war in the country. The aim of the present study was to describe the knowledge, attitudes and practices (KAPs) of at-risk urban populations residing in Taiz, southwest of Yemen. In addition, factors possibly associated with poor preventive practices were investigated. METHODS A household-based, cross-sectional survey was conducted in three urban districts encompassing 383 households. Data on the socio-demographic characteristics and KAPs of the participating household heads were collected using a pre-designed, structured questionnaire. The association of socio-demographic characteristics, knowledge and attitudes of the population with poor preventive practices against dengue fever was then analyzed using logistic regression. RESULTS More than 90.0 % of respondent household heads had correct knowledge about fever, headache and joint pain as common signs and symptoms of dengue fever. Moreover, muscular pain and bleeding were perceived by more than 80.0 % of the respondents as being associated with dengue fever; however, only 65.0 % of the respondents reported skin rash as a sign of dengue fever. More than 95.0 % of respondents agreed about the seriousness and possible transmission of dengue fever; however, negative attitudes regarding the facts of being at risk of the disease and that the infection is preventable were expressed by 15.0 % of respondents. Despite the good level of knowledge and attitudes of the respondent population, poor preventive practices were common. Bivariate analysis identified poor knowledge of dengue signs and symptoms (OR = 2.1, 95 % CI = 1.24-3.68; P = 0.005) and its vector (OR = 2.1, 95 % CI = 1.14-3.84; P = 0.016) as factors significantly associated with poor preventive practices. However, multivariable analysis showed that poor knowledge of the vector is an independent predictor of poor preventive practices of the population (adjusted OR = 2.1, 95 % CI = 1.14-3.84; P = 0.018). CONCLUSION The majority of people in urban communities of Taiz have a clear understanding of most signs/symptoms of dengue fever as well as positive attitudes towards the seriousness and possible transmissibility of dengue fever. However, negative attitudes regarding their perception of the risk and possible prevention of the infection are prevailing among a small proportion of the population and need to be targeted by educational campaigns. It appears that the good level of the population knowledge of the signs/symptoms of dengue fever and the factors contributing to the spread and control of its vectors did not translate into good practices.
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Affiliation(s)
- Thaker A A Alyousefi
- Department of Hematology, Faculty of Medical Sciences, Al-Razi University, Sana'a, Yemen
| | - Rashad Abdul-Ghani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen. .,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen.
| | - Samira M A Al-Eryani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Abdulsalam M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Yahia A Raja
- Faculty of Public Health and Informatics, Umm Al-Qura University, Mecca, Saudi Arabia
| | - Shamusul Azhar Shah
- Department of Community Health, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
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13
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Abdul-Ghani R, Mahdy MAK, Saif-Ali R, Alkubati SA, Alqubaty AR, Al-Mikhlafy AA, Al-Eryani SM, Al-Mekhlafi AM, Alhaj A. Glucose-6-phosphate dehydrogenase deficiency among Yemeni children residing in malaria-endemic areas of Hodeidah governorate and evaluation of a rapid diagnostic test for its detection. Malar J 2016; 15:327. [PMID: 27329471 PMCID: PMC4915072 DOI: 10.1186/s12936-016-1372-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/01/2016] [Accepted: 06/03/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common genetic enzymopathy worldwide, is associated with an acute haemolytic anaemia in individuals exposed to primaquine. The present study aimed to determine G6PD deficiency among Yemeni children in malaria-endemic areas as well as to assess the performance of the CareStart™ G6PD rapid diagnostic test (RDT) for its detection. METHODS A cross-sectional study recruiting 400 children from two rural districts in Hodeidah governorate was conducted. Socio-demographic data and blood samples were collected and G6PD deficiency was qualitatively detected in fresh blood in the field using the CareStart™ G6PD RDT, while the enzymatic assay was used to quantitatively measure enzyme activity. Performance of the CareStart™ G6PD RDT was assessed by calculating its sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) against the reference enzymatic assay. RESULTS The ranges of enzyme activity were 0.14-18.45 and 0.21-15.94 units/g haemoglobin (U/gHb) for males and females, respectively. However, adjusted male median G6PD activity was 5.0 U/gHb. Considering the adjusted male median as representing 100 % normal enzyme activity, the prevalence rates of G6PD deficiency were 12.0 and 2.3 % at the cut-off activities of ≤60 and ≤10 %, respectively. Multivariable analysis showed that gender, district of residence and consanguinity between parents were independent risk factors for G6PD deficiency at the cut-off activity of ≤30 % of normal. The CareStart™ G6PD RDT showed 100 % sensitivity and NPV for detecting G6PD deficiency at the cut-off activities of ≤10 and ≤20 % of normal activity compared to the reference enzymatic method. However, it showed specificity levels of 90.0 and 95.4 % as well as positive/deficient predictive values (PPVs) of 18.0 and 66.0 % at the cut-off activities of ≤10 and ≤20 %, respectively, compared to the reference method. CONCLUSIONS G6PD deficiency with enzyme activity of ≤60 % of normal is prevalent among 12.0 % of children residing in malaria-endemic areas of Hodeidah governorate, with 2.3 % having severe G6PD deficiency. Gender, district of residence and consanguinity between parents are significant independent predictors of G6PD deficiency at the cut-off activity of ≤30 % of normal among children in malaria-endemic areas of Hodeidah. The CareStart™ G6PD RDT proved reliable as a point-of-care test to screen for severely G6PD-deficient patients, with 100 % sensitivity and NPV, and it can be used for making clinical decisions prior to the administration of primaquine in malaria elimination strategies.
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Affiliation(s)
- Rashad Abdul-Ghani
- />Tropical Disease Research Center, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a, Yemen
- />Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Mohammed A. K. Mahdy
- />Tropical Disease Research Center, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a, Yemen
- />Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Reyadh Saif-Ali
- />Department of Biochemistry, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Sameer A. Alkubati
- />Department of Critical Care Nursing, Faculty of Medicine and Health Sciences, Hodeidah University, Hodeidah, Yemen
| | - Abdulhabib R. Alqubaty
- />Department of Biochemistry, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a, Yemen
| | - Abdullah A. Al-Mikhlafy
- />Department of Community Medicine, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a, Yemen
| | - Samira M. Al-Eryani
- />Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Abdusalam M. Al-Mekhlafi
- />Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Ali Alhaj
- />Department of Biochemistry, Faculty of Medicine and Health Sciences, University of Science and Technology, Sana’a, Yemen
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14
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Mahdy MAK, Al-Mekhlafi AM, Abdul-Ghani R, Saif-Ali R, Al-Mekhlafi HM, Al-Eryani SM, Lim YAL, Mahmud R. First Molecular Characterization of Leishmania Species Causing Visceral Leishmaniasis among Children in Yemen. PLoS One 2016; 11:e0151265. [PMID: 26966902 PMCID: PMC4788415 DOI: 10.1371/journal.pone.0151265] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 02/25/2016] [Indexed: 11/19/2022] Open
Abstract
Visceral leishmaniasis (VL) is a debilitating, often fatal disease caused by Leishmania donovani complex; however, it is a neglected tropical disease. L. donovani complex comprises two closely related species, L. donovani that is mostly anthroponotic and L. infantum that is zoonotic. Differentiation between these two species is critical due to the differences in their epidemiology and pathology. However, they cannot be differentiated morphologically, and their speciation using isoenzyme-based methods poses a difficult task and may be unreliable. Molecular characterization is now the most reliable method to differentiate between them and to determine their phylogenetic relationships. The present study aims to characterize Leishmania species isolated from bone marrows of Yemeni pediatric patients using sequence analysis of the ribosomal internal transcribed spacer-1 (ITS1) gene. Out of 41 isolates from Giemsa-stained bone marrow smears, 25 isolates were successfully amplified by nested polymerase chain reaction and sequenced in both directions. Phylogenetic analysis using neighbor joining method placed all study isolates in one cluster with L. donovani complex (99% bootstrap). The analysis of ITS1 for microsatellite repeat numbers identified L. infantum in 11 isolates and L. donovani in 14 isolates. These data suggest the possibility of both anthroponotic and zoonotic transmission of VL-causing Leishmania species in Yemen. Exploring the possible animal reservoir hosts is therefore needed for effective control to be achieved.
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Affiliation(s)
- Mohammed A. K. Mahdy
- Tropical Disease Research Center, Faculty of Medicine, University of Science and Technology, Sana’a, Yemen
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
- * E-mail:
| | - Abdulsalam M. Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Rashad Abdul-Ghani
- Tropical Disease Research Center, Faculty of Medicine, University of Science and Technology, Sana’a, Yemen
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Reyadh Saif-Ali
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Hesham M. Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Samira M. Al-Eryani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen
| | - Yvonne A. L. Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
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15
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Alareqi LMQ, Mahdy MAK, Lau YL, Fong MY, Abdul-Ghani R, Ali AA, Cheong FW, Tawfek R, Mahmud R. Field evaluation of a PfHRP-2/pLDH rapid diagnostic test and light microscopy for diagnosis and screening of falciparum malaria during the peak seasonal transmission in an endemic area in Yemen. Malar J 2016; 15:49. [PMID: 26821911 PMCID: PMC4730713 DOI: 10.1186/s12936-016-1103-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 01/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria is a public health threat in Yemen, with 149,451 cases being reported in 2013. Of these, Plasmodium falciparum represents 99%. Prompt diagnosis by light microscopy (LM) and rapid diagnostic tests (RTDs) is a key element in the national strategy of malaria control. The heterogeneous epidemiology of malaria in the country necessitates the field evaluation of the current diagnostic strategies, especially RDTs. Thus, the present study aimed to evaluate LM and an RDT, combining both P. falciparum histidine-rich protein-2 (PfHRP-2) and Plasmodium lactate dehydrogenase (pLDH), for falciparum malaria diagnosis and survey in a malaria-endemic area during the transmission season against nested polymerase chain reaction (PCR) as the reference method. METHODS A household-based, cross-sectional malaria survey was conducted in Mawza District, a malaria-endemic area in Taiz governorate. A total of 488 participants were screened using LM and PfHRP-2/pLDH RDT. Positive samples (160) and randomly selected negative samples (52) by both RDT and LM were further analysed using 18S rRNA-based nested PCR. RESULTS The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the RDT were 96.0% (95% confidence interval (CI): 90.9-98.3), 56.0% (95% CI: 44.7-66.8), 76.3% (95% CI: 69.0-82.3), and 90.4% (95% CI: 78.8-96.8), respectively. On the other hand, LM showed sensitivity of 37.6% (95% CI: 29.6-46.3), specificity of 97.6% (95% CI: 91.7-99.7), PPV of 95.9% (95% CI: 86.3-98.9), and NPV of 51.3% (95% CI: 43.2-59.2). The sensitivity of LM dropped to 8.5% for detecting asymptomatic malaria. Malaria prevalence was 32.8% (32.1 and 37.5% for ≥10 and <10 years, respectively) with the RDT compared with 10.7% (10.8 and 9.4% for age groups of ≥10 and <10 years, respectively) with LM. Among asymptomatic malaria individuals, LM and RDT-based prevalence rates were 1.6 and 25.6%, respectively. However, rates of 88.2 and 94.1% of infection with P. falciparum were found among patients who reported fever in the 48 h prior to the survey by LM and PfHRP-2/pLDH RDT, respectively. CONCLUSIONS The PfHRP-2/pLDH RDT shows high sensitivity for the survey of falciparum malaria even for asymptomatic malaria cases. Although the RDT had high sensitivity, its high false-positivity rate limits its utility as a single diagnostic tool for clinical diagnosis of malaria. On the other hand, low sensitivity of LM indicates that a high proportion of malaria cases is missed, underestimating the true prevalence of malaria in the community. Higher NPV of PfHRP-2/pLDH RDT than LM can give a straightforward exclusion of malaria among febrile patients, helping to avoid unnecessary presumptive treatments.
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Affiliation(s)
- Lina M Q Alareqi
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Mohammed A K Mahdy
- Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen. .,Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.
| | - Yee-Ling Lau
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Mun-Yik Fong
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Rashad Abdul-Ghani
- Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen. .,Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.
| | - Arwa A Ali
- Yemeni-Swedish Hospital, Ministry of Public Health and Population, Taiz, Yemen.
| | - Fei-Wen Cheong
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Rehab Tawfek
- Yemeni-Swedish Hospital, Ministry of Public Health and Population, Taiz, Yemen.
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Bamaga OAA, Mahdy MAK, Lim YAL. Frequencies distribution of dihydrofolate reductase and dihydropteroate synthetase mutant alleles associated with sulfadoxine-pyrimethamine resistance in Plasmodium falciparum population from Hadhramout Governorate, Yemen. Malar J 2015; 14:516. [PMID: 26693691 PMCID: PMC4688959 DOI: 10.1186/s12936-015-1035-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/04/2015] [Indexed: 12/23/2022] Open
Abstract
Background Malaria in Yemen is mainly caused by Plasmodium falciparum and 25 % of the population is at high risk. Sulfadoxine–pyrimethamine (SP) had been used as monotherapy against P. falciparum. Emergence of chloroquine resistance led to the shift in anti-malarial treatment policy in Yemen to artemisinin-based combination therapy, that is artesunate (AS) plus SP as first-line therapy for uncomplicated malaria and artemether–lumefantrine as second-line treatment. This study aimed to screen mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) genes associated with SP resistance among P. falciparum population in Hadhramout governorate, Yemen. Methods Genomic DNA was extracted from dried blood spots of 137 P. falciparum isolates collected from a community-based study. DNA was amplified using nested polymerase chain reaction (PCR) and subsequently sequenced for Pfdhfr and Pfdhps genes. Sequences were analysed for mutations in Pfdhfr gene codons 51, 59, 108, and 164 and in Pfdhps gene codons 436, 437, and 540. Results A total of 128 and 114 P. falciparum isolates were successfully sequenced for Pfdhfr and Pfdhps genes, respectively. Each Pfdhfr mutant allele (I51 and N108) in P. falciparum population had a frequency of 84 %. PfdhfrR59 mutant allele was detected in one isolate. Mutation at codon 437 (G437) in the Pfdhps gene was detected in 44.7 % of falciparum malaria isolates. Frequencies of Pfdhfr double mutant genotype (I51C59N108I164) and Pfdhfr/Pfdhps triple mutant genotype (I51C59N108I164-S436G437K540) were 82.8 and 39.3 %, respectively. One isolate harboured Pfdhfr triple mutant genotype (I51, R59, N108, I164) and Pfdhfr/Pfdhps quadruple mutant genotype (I51R59N108I164-S436G437K540). Conclusion High frequencies of Pfdhfr and Pfdhps mutant alleles and genotypes in P. falciparum population in Hadhramout, Yemen, highlight the risk of developing resistance for SP, the partner drug of AS, which subsequently will expose the parasite to AS monotherapy increasing then the potential of the emergence of AS resistance. Study findings necessitate the continuous monitoring of the efficacy of the national anti-malarial drugs policy in Yemen. In addition, monitoring SP efficacy using molecular markers that has shown to be a practical and informative method for monitoring the partner drug of AS.
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Affiliation(s)
- Omar A A Bamaga
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen. .,Tropical Disease Research Centre, University of Science and Technology, Taiz, Yemen.
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Abdul-Ghani R, Basco LK, Beier JC, Mahdy MAK. Inclusion of gametocyte parameters in anti-malarial drug efficacy studies: filling a neglected gap needed for malaria elimination. Malar J 2015; 14:413. [PMID: 26481312 PMCID: PMC4617745 DOI: 10.1186/s12936-015-0936-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 10/09/2015] [Indexed: 11/29/2022] Open
Abstract
Standard anti-malarial drug efficacy and drug resistance assessments neglect the gametocyte parameters in their protocols. With the spread of drug resistance and the absence of clinically proven vaccines, the use of gametocytocidal drugs or drug combinations with transmission-blocking activity is a high priority for malaria control and elimination. However, the limited repertoire of gametocytocidal drugs and induction of gametocytogenesis after treatment with certain anti-malarial drugs necessitate both regular monitoring
of gametocytocidal activities of anti-malarial drugs in clinical use and the effectiveness of candidate gametocytocidal agents. Therefore, updating current protocols of anti-malarial drug efficacy is needed to reflect the effects of anti-malarial drugs or drug combinations on gametocyte carriage and gametocyte density along with asexual parasite density. Developing protocols of anti-malarial drug efficacy that include gametocyte parameters related to both microscopic and submicroscopic gametocytaemias is important if drugs or drug combinations are to be strategically used in transmission-blocking interventions in the context of malaria elimination. The present piece of opinion highlights the challenges in gametocyte detection and follow-up and discuss the need for including the gametocyte parameter in anti-malarial efficacy studies.
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Affiliation(s)
- Rashad Abdul-Ghani
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen. .,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen.
| | - Leonardo K Basco
- Unité de Recherche 198, Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Institut de Recherche pour le Développement, Faculté de Médecine La Timone, Aix-Marseille Université, Marseille, France.
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA.
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen. .,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen.
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Choy SH, Mahdy MAK, Al-Mekhlafi HM, Low VL, Surin J. Population expansion and gene flow in Giardia duodenalis as revealed by triosephosphate isomerase gene. Parasit Vectors 2015; 8:454. [PMID: 26373536 PMCID: PMC4572684 DOI: 10.1186/s13071-015-1084-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 09/10/2015] [Indexed: 12/21/2022] Open
Abstract
Background Giardia duodenalis is a protozoan parasite that can cause significant diarrhoeal diseases. Knowledge of population genetics is a prerequisite for ascertaining the invasion patterns of this parasite. In order to infer evolutionary patterns that could not be uncovered based on the morphological features, a population genetic study with the incorporation of molecular marker was carried out to access the genetic structure of G. duodenalis isolated from the Malaysian population and the global populations. Methods A total of 154 samples positive for Giardia, collected from different Malaysian communities, were subjected to DNA amplification and sequencing targeting three genetic loci (tpi, gdh, and bg). The tpi sequences together with sequences from the global data obtained from the NCBI GenBank were used for genetic diversity analyses including identification of haplotypes, haplotype diversity, nucleotide diversity, Tajima’s D and Fu and Li’s D, gene flow and genetic differentiation tests. Results Analysis of the Malaysian and global data showed that assemblages A, B, and E (the most prevalent assemblages in humans and animals), have different levels of genetic diversity. Assemblage B had the highest level of both haplotype diversity and nucleotide diversity, followed by assemblage E. The analysis also revealed population expansion and high gene flow in all assemblages. No clear genetic structure was observed across five continents (i.e., the Americas, Europe, Asia, Australia and Africa). However, median joining network of assemblage B formed a cluster that was exclusively isolated from Asia while other haplotypes were well dispersed across the continents. Conclusions This study provides new insight into the genetic diversity of Giardia assemblages in different geographical regions. The significant result shown by gene flow and genetic differentiation analyses as well as test of neutrality among the populations should have brought a clearer picture to the dynamics and distribution of Giardia infection.
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Affiliation(s)
- Seow Huey Choy
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine and Health Science, Sana'a University, Sana'a, Yemen. .,Tropical Disease Research Center, University of Science and Technology, Sana'a, Yemen.
| | - Hesham M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia. .,Department of Parasitology, Faculty of Medicine and Health Science, Sana'a University, Sana'a, Yemen.
| | - Van Lun Low
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Johari Surin
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Choy SH, Al-Mekhlafi HM, Mahdy MAK, Nasr NN, Sulaiman M, Lim YAL, Surin J. Prevalence and associated risk factors of Giardia infection among indigenous communities in rural Malaysia. Sci Rep 2014; 4:6909. [PMID: 25366301 PMCID: PMC4219160 DOI: 10.1038/srep06909] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 10/15/2014] [Indexed: 12/17/2022] Open
Abstract
This study was carried out to investigate the prevalence and risk factors of Giardia infection among indigenous people in rural Malaysia. Faecal samples were collected from 1,330 participants from seven states of Malaysia and examined by wet mount and formalin-ether sedimentation methods while demographic, socioeconomic and environmental information was collected using a pre-tested questionnaire. The overall prevalence of Giardia infection was 11.6% and was significantly higher among those aged ≤ 12 years compared to their older counterparts. Multivariate logistic regression identified age of ≤12 years, lacking of toilet at household, not washing hands before eating, not washing hands after playing with animals, not boiling water before consumption, bathing in the river, and not wearing shoes when outside as the significant risk factors of Giardia infection among these communities. Based on a multilocus genotyping approach (including tpi, gdh and bg gene sequences), 69 isolates were identified as assemblage A, and 69 as assemblage B. No association between the assemblages and presence of symptoms was found. Providing proper sanitation, as well as provision of clean drinking water and proper health education regarding good personal hygiene practices will help significantly in reducing the prevalence and burden of Giardia infection in these communities.
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Affiliation(s)
- Seow Huey Choy
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Hesham M Al-Mekhlafi
- 1] Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia [2] Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Mohammed A K Mahdy
- 1] Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia [2] Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | - Nabil N Nasr
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Maria Sulaiman
- Contagious Diseases Division, Sabah Health Department, Kota Kinabalu, Sabah, Malaysia
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Johari Surin
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Al-Mekhlafi HM, Anuar TS, Al-Zabedi EM, Al-Maktari MT, Mahdy MAK, Ahmed A, Sallam AA, Abdullah WA, Moktar N, Surin J. Does vitamin A supplementation protect schoolchildren from acquiring soil-transmitted helminthiasis? A randomized controlled trial. Parasit Vectors 2014; 7:367. [PMID: 25127885 PMCID: PMC4141119 DOI: 10.1186/1756-3305-7-367] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 07/29/2014] [Indexed: 11/27/2022] Open
Abstract
Background Despite the intensive global efforts to control intestinal parasitic infections, the prevalence of soil-transmitted helminth (STH) infections is still very high in many developing countries particularly among children in rural areas. Methods A randomized, double-blind, placebo-controlled trial was conducted on 250 Aboriginal schoolchildren in Malaysia to investigate the effects of a single high-dose of vitamin A supplementation (200 000 IU) on STH reinfection. The effect of the supplement was assessed at 3 and 6 months after receiving interventions; after a complete 3-day deworming course of 400 mg/daily of albendazole tablets. Results Almost all children (98.6%) were infected with at least one STH species. The overall prevalence of ascariasis, trichuriasis and hookworm infection was 67.8%, 95.5% and 13.4%, respectively. Reinfection rates of Ascaris, Trichuris and hookworm were high; at 6 months, assessment reached 80% of the prevalence reported before treatment. There were no significant differences in the reinfection rates and intensities of STH between vitamin A supplemented-children and those who received placebo at 3 and 6 months (p > 0.05). Conclusions Vitamin A supplementation showed no protective effect against STH reinfection and this could be due to the high endemicity of STH in this community. Long-term interventions to reduce poverty will help significantly in reducing this continuing problem and there is no doubt that reducing intestinal parasitic infection would have a positive impact on the health, nutrition and education of these children. Trial registration This trial was registered at clinicaltrials.gov as NCT00936091.
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Affiliation(s)
- Hesham M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Bamaga OAA, Mahdy MAK, Mahmud R, Lim YAL. Malaria in Hadhramout, a southeast province of Yemen: prevalence, risk factors, knowledge, attitude and practices (KAPs). Parasit Vectors 2014; 7:351. [PMID: 25074325 PMCID: PMC4141094 DOI: 10.1186/1756-3305-7-351] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 07/19/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Yemen is a Mediterranean country where 65% of its population is at risk of malaria, with 43% at high risk. Yemen is still in the control phase without sustainable reduction in the proportion of malaria cases. A cross-sectional household survey was carried out in different districts in the southeast of the country to determine malaria prevalence and identify factors that impede progress of the elimination phase. METHODS Blood specimens were collected from 735 individuals aged 1-66 years. Plasmodium species were detected and identified by microscopic examination of Giemsa-stained thick and thin blood smears. A household-based questionnaire was used to collect demographic, socioeconomic and environmental data. RESULTS The overall prevalence of malaria was 18.8% with Plasmodium falciparum as the predominant species (99.3%), with a low rate of Plasmodium vivax detected (0.7%). The infection rate was higher in Al-Raydah and Qusyer districts (21.8%) compared to Hajer district (11.8%). Fifty-two percent of the persons positive for Plasmodium were asymptomatic with low parasite density. The adults had a higher infection rate as compared to children. Univariate analysis identified those whose household's head are fishermen (OR = 11.3, 95% CI: 3.13-40.5) and farmers (OR = 4.84, 95% CI: 1.73-13.6) as high-risk groups. A higher number of positive smears were observed in people living in houses with uncemented brick walls (OR = 2.1, 95% CI: 1.32-3.30), without access to toilets (OR = 1.6, 95% CI: 1.05-2.32), without a fridge (OR = 1. 6, 95% CI: 1.05-2.30), or without TV (OR = 1. 6, (95% CI: 1.05-2.30). People living in houses with water collection points located less than 200 meters away were also at higher risk of acquiring malaria (OR = 1.6, 95% CI: 1.05-2.30). Knowledge about the importance of using insecticide-treated mosquito nets (ITNs) and indoor residual spraying (IRS) for prevention of malaria was 7% and 2%, respectively. CONCLUSIONS Several environmental, socioeconomic and behavioral issues were discovered to be the contributing factors to the high prevalence of malaria in southeast Yemen. Novel strategies adapted to the local situations need to be established in order to improve the effectiveness of malaria control.
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Affiliation(s)
| | - Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Al-Hamidhi S, Mahdy MAK, Idris MA, Bin Dajem SM, Al-Sheikh AAH, Al-Qahtani A, Al-Hashami Z, Al-Farsi H, Al-Mekhlafi AM, Saif-Ali R, Beja-Pereira A, Babiker HA. The prospect of malaria elimination in the Arabian Peninsula: a population genetic approach. Infect Genet Evol 2014; 27:25-31. [PMID: 24981966 DOI: 10.1016/j.meegid.2014.06.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 03/21/2014] [Accepted: 06/17/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND In the Arabian Peninsula malaria control is progressing steadily, backed by adequate logistic and political support. As a result, transmission has been interrupted throughout the region, with exception of limited sites in Yemen and Saudi Arabia. Here we examined Plasmodium falciparum parasites in these sites to assess if the above success has limited diversity and gene flow. METHODS We examined 108 P. falciparum isolates in three sites in Yemen (Taiz, Dhamar and Hodeidah) and 91 isolates from Saudi Arabia (Jazan). Nine microsatellites were analyzed for allelic diversity, multi-locus haplotype and inter-population differentiation. RESULTS Diversity at each locus (unbiased heterozygosity [H]) was relatively lower in Yemen; (Hodeidah, H=0.615, Taiz, H=0.66, Dhamar, H=0.481), compared to Saudi Arabia (Jazan, H=0.76). Microsatellites were distributed widely and private alleles, detected in a single population, were rare. Pairwise comparisons revealed that parasites population in Dhamar was relatively distanced (FST=0.19). However, Taiz (Yemen) (FST=0.065) and Hodeidah (FST=0.107) populations were closer to that in Jazan (Saudi Arabia). Nonetheless, parasites in the four sites can be considered as one population. CONCLUSION Although malaria risk in Saudi Arabia has been cut considerably, the extent of diversity and parasite genetic structure are indicative of a large population size. Elimination strategy should target demographic factors that favor parasite dispersal and flow of imported malaria.
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Affiliation(s)
- Salama Al-Hamidhi
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Sultan Qaboos University, Oman
| | - Mohammed A K Mahdy
- Research Department, University of Science and Technology, Sana'a, Yemen; Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Mohamed Ahmed Idris
- Department of Microbiology and Immunology, Faculty of Medicine and Health Sciences, Sultan Qaboos University, Oman
| | - Saad M Bin Dajem
- Biology Department, College of Science, King Khalid University, Abha, Saudi Arabia
| | | | - Ahmed Al-Qahtani
- Medical Research, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Zainab Al-Hashami
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Sultan Qaboos University, Oman
| | - Hissa Al-Farsi
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Sultan Qaboos University, Oman
| | - Abdulsalam M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Riyadh Saif-Ali
- Biochemistry Department, Faculty of Medicine, Sana'a University, Yemen
| | - Albano Beja-Pereira
- Research Centre in Biodiversity and Genetic Resources (CIBIO), University of Porto, Rua Padre Armando Quintas 7, Vairão 4485-661, Portugal
| | - Hamza A Babiker
- Department of Biochemistry, Faculty of Medicine and Health Sciences, Sultan Qaboos University, Oman.
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Al-Mekhlafi HM, Al-Maktari MT, Jani R, Ahmed A, Anuar TS, Moktar N, Mahdy MAK, Lim YAL, Mahmud R, Surin J. Burden of Giardia duodenalis infection and its adverse effects on growth of schoolchildren in rural Malaysia. PLoS Negl Trop Dis 2013; 7:e2516. [PMID: 24205426 PMCID: PMC3814875 DOI: 10.1371/journal.pntd.0002516] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 09/22/2013] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Giardia duodenalis infection and malnutrition are still considered as public health problems in many developing countries especially among children in rural communities. This study was carried out among Aboriginal (Orang Asli) primary schoolchildren in rural peninsular Malaysia to investigate the burden and the effects of Giardia infection on growth (weight and height) of the children. METHODS/FINDINGS Weight and height of 374 children aged 7-12 years were assessed before and after treatment of Giardia infection. The children were screened for Giardia parasite using trichrome staining technique. Demographic and socioeconomic data were collected via face-to-face interviews using a pre-tested questionnaire. Overall, 22.2% (83/374) of the children were found to be infected with Giardia. Nutritional status of children was assessed and the results showed that the mean weight and height were 23.9 kg (95% CI = 23.3, 24.5) and 126.6 cm (95% CI = 125.6, 127.5), respectively. Overall, the prevalence of severe underweight, stunting and wasting were 28.3%, 23.8% and 21.0%, respectively. Multiple linear regression analyses showed sex, Giardia infection and household monthly income as the significant determinants of weight while sex and level of mother's education were the significant determinants of height. Weight and height were assessed at 3 and 6 months after treatment of Giardia infection. It was found that Giardia infection has a significant association with the weight of children but not with height. CONCLUSIONS/SIGNIFICANCE This study reveals high prevalence of Giardia infection and malnutrition among Aboriginal children in rural Malaysia and clearly highlights an urgent need to identify integrated measures to control these health problems in the rural communities. Essentially, proper attention should be given to the control of Giardia infection in Aboriginal communities as this constitutes one of the strategies to improve the nutritional status of Aboriginal children.
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Affiliation(s)
- Hesham M. Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Medical Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Mohamed T. Al-Maktari
- Department of Medical Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Rohana Jani
- Department of Applied Statistics, Faculty of Economics and Administration, University of Malaya, Kuala Lumpur, Malaysia
| | - Abdulhamid Ahmed
- Department of Biology, Faculty of Natural and Applied Sciences, Umaru Musa Yar'adua University, Katsina. Katsina State, Nigeria
| | - Tengku Shahrul Anuar
- Department of Medical Laboratory Technology, Faculty of Health Sciences, Universiti Teknologi MARA (Puncak Alam Campus), Selangor, Malaysia
| | - Norhayati Moktar
- Department of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Mohammed A. K. Mahdy
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Medical Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Yvonne A. L. Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Johari Surin
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Ngui R, Mahdy MAK, Chua KH, Traub R, Lim YAL. Genetic characterization of the partial mitochondrial cytochrome oxidase c subunit I (cox 1) gene of the zoonotic parasitic nematode, Ancylostoma ceylanicum from humans, dogs and cats. Acta Trop 2013; 128:154-7. [PMID: 23774318 DOI: 10.1016/j.actatropica.2013.06.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 06/04/2013] [Accepted: 06/05/2013] [Indexed: 12/01/2022]
Abstract
Ancylostoma ceylanicum is the only zoonotic hookworm species that is able to produce patent infections in humans with the majority of cases reported in South East Asia. Over the past few years, there have been an increasing number of studies investigating the prevalence of this parasitic zoonosis using molecular diagnostic tools and a single genetic locus as marker for species identification. As there can be limitations in using a single genetic locus for epidemiological studies and genetic discrimination, the complementary use of a more variable locus will provide additional evidence to support the zoonotic exchange of hookworm species between humans and animals. In the present study, the cytochrome c oxidase subunit 1 (cox 1) sequence of A. ceylanicum from positive human and animal fecal samples were determined and compared with published reference sequences. Phylogenetic analysis demonstrated that isolates of A. ceylanicum were divided into two clusters, one consisting 3 human isolates and the other comprising 19 isolates of human and animal origin from different geographical locations within Malaysia. The two groups of A. ceylanicum could be distinguished from one another through five fixed nucleotide differences at locations 891, 966, 1008, 1077 and 1083. The detection of genetically distinct groups and considerable level of genetic variation within the cox 1 sequence of A. ceylanicum might suggest potential haplotype-linked differences in zoonotic, epidemiological and pathobiological characteristics, a hypothesis that still needs further investigation.
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Affiliation(s)
- Romano Ngui
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Sady H, Al-Mekhlafi HM, Mahdy MAK, Lim YAL, Mahmud R, Surin J. Prevalence and associated factors of Schistosomiasis among children in Yemen: implications for an effective control programme. PLoS Negl Trop Dis 2013; 7:e2377. [PMID: 23991235 PMCID: PMC3749985 DOI: 10.1371/journal.pntd.0002377] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 07/04/2013] [Indexed: 11/18/2022] Open
Abstract
Background Schistosomiasis, one of the most prevalent neglected tropical diseases, is a life-threatening public health problem in Yemen especially in rural communities. This cross-sectional study aims to determine the prevalence and associated risk factors of schistosomiasis among children in rural Yemen. Methods/Findings Urine and faecal samples were collected from 400 children. Urine samples were examined using filtration technique for the presence of Schistosoma haematobium eggs while faecal samples were examined using formalin-ether concentration and Kato Katz techniques for the presence of S. mansoni. Demographic, socioeconomic and environmental information were collected via a validated questionnaire. Overall, 31.8% of the participants were found to be positive for schistosomiasis; 23.8% were infected with S. haematobium and 9.3% were infected with S. mansoni. Moreover, 39.5% of the participants were anaemic whereas 9.5% had hepatosplenomegaly. The prevalence of schistosomiasis was significantly higher among children aged >10 years compared to those aged ≤10 years (P<0.05). Multivariate analysis confirmed that presence of other infected family member (P<0.001), low household monthly income (P = 0.003), using unsafe sources for drinking water (P = 0.003), living nearby stream/spring (P = 0.006) and living nearby pool/pond (P = 0.002) were the key factors significantly associated with schistosomiasis among these children. Conclusions/Significance This study reveals that schistosomiasis is still highly prevalent in Yemen. These findings support an urgent need to start an integrated, targeted and effective schistosomiasis control programme with a mission to move towards the elimination phase. Besides periodic drug distribution, health education and community mobilisation, provision of clean and safe drinking water, introduction of proper sanitation are imperative among these communities in order to curtail the transmission and morbidity caused by schistosomiasis. Screening and treating other infected family members should also be adopted by the public health authorities in combating this infection in these communities. Schistosomiasis remains one of the most serious and prevalent diseases worldwide. Despite intensive control efforts by the government and international bodies, schistosomiasis is the second cause of death, after malaria, in Yemen, with an estimated 3 million cases. We screened 400 children in rural areas of five provinces in Yemen for the presence of schistosomiasis. Overall, 31.8% of the children were found to be positive for schistosomiasis; 23.8% were infected by Schistosoma haematobium, and 9.3% were infected by S. mansoni. The study identified the presence of other family members infected with schistosomiasis, low household monthly income, using unsafe water supply as a source for drinking water, living nearby stream/spring and/or pool/pond as the key factors significantly associated with schistosomiasis in these communities. Innovative and integrated control measures to control this infection should be implemented among this population. Periodic school-based and community-based drug distribution, health education, provision of clean and safe drinking water, introduction of proper sanitation will help to reduce the prevalence and morbidity of schistosomiasis among these communities.
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Affiliation(s)
- Hany Sady
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Hesham M. Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
- * E-mail:
| | - Mohammed A. K. Mahdy
- Department of Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
- Research Department, University of Science and Technology, Sana'a, Yemen
| | - Yvonne A. L. Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Johari Surin
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Al-Hamidhi S, Mahdy MAK, Al-Hashami Z, Al-Farsi H, Al-mekhlafi AM, Idris MA, Beja-Pereira A, Babiker HA. Genetic diversity of Plasmodium falciparum and distribution of drug resistance haplotypes in Yemen. Malar J 2013; 12:244. [PMID: 23855834 PMCID: PMC3729657 DOI: 10.1186/1475-2875-12-244] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Accepted: 07/11/2013] [Indexed: 11/25/2022] Open
Abstract
Background Despite evident success of malaria control in many sites in the Arabian Peninsula, malaria remains endemic in a few spots, in Yemen and south-west of Saudi Arabia. In addition to local transmission, imported malaria sustains an extra source of parasites that can challenge the strengths of local control strategies. This study examined the genetic diversity of Plasmodium falciparum in Yemen and mutations of drug resistant genes, to elucidate parasite structure and distribution of drug resistance genotypes in the region. Methods Five polymorphic loci (MSP-2, Pfg377 and three microsatellites on chromosome 8) not involved in anti-malarial drug resistance, and four drug resistant genes (pfcrt, pfmdr1, dhfr and dhps) were genotyped in 108 P. falciparum isolates collected in three sites in Yemen: Dhamar, Hodeidah and Taiz. Results High diversity was seen in non-drug genes, pfg377 (He = 0.66), msp-2 (He = 0.80) and three microsatellites on chr 8, 7.7 kb (He = 0.88), 4.3 kb (He = 0.77) and 0.8 kb (He = 0.71). There was a high level of mixed-genotype infections (57%), with an average 1.8 genotypes per patient. No linkage disequilibrium was seen between drug resistant genes and the non-drug markers (p < 0.05). Genetic differentiation between populations was low (most pair-wise FST values <0.03), indicating extensive gene flow between the parasites in the three sites. There was a high prevalence of mutations in pfmdr1, pfcrt and dhfr; with four mutant pfmdr1 genotypes (NFCDD[57%], NFSND[21%], YFCDD[13%] and YFSND[8% ]), two mutant pfcrt genotypes (CVIET[89%] and SVMNT[4%]) and one mutant dhfr genotype (ICNI[53.7%]). However, no dhps mutations were detected. Conclusion The high diversity of P. falciparum in Yemen is indicative of a large parasite reservoir, which represents a challenge to control efforts. The presence of two distinct pfcrt genotype, CVIET and SVMNT, suggests that chloroquine resistance can possibly be related to a migratory path from Africa and Asia. The absence of the triple mutant dhfr genotype (IRN) and dhps mutations supports the use of artesunate + sulphadoxine-pyrimethamine as first-line therapy. However, the prevalent pfmdr1 genotype NFSND [21%] has previously been associated with tolerance/resistance response to artemisinin combination therapy (ACT). Regular surveys are, therefore, important to monitor spread of pfmdr1 and dhfr mutations and response to ACT.
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Alyousefi NA, Mahdy MAK, Xiao L, Mahmud R, Lim YAL. Molecular characterization of Giardia duodenalis in Yemen. Exp Parasitol 2013; 134:141-7. [PMID: 23523861 DOI: 10.1016/j.exppara.2013.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 11/20/2012] [Accepted: 03/02/2013] [Indexed: 10/27/2022]
Abstract
Giardia duodenalis is an important intestinal protozoan in Yemen with infection rates ranging from 18% to 27%. To date, there has been no genotyping study to provide a better understanding of the transmission dynamic. This study was conducted to genotype and subtype G. duodenalis in Yemen. Stool samples were collected from 503 Yemeni outpatients between 1 and 80 years old, including 219 males and 284 females. Giardia cysts were detected via microscopy after the formal-ether concentration. Genotyping of Giardia was carried out using PCR and sequence analysis of the 16s rRNA and b-giardin genes. Of the 89 microscopy-positive Giardia samples, 65 were successfully sequenced, of which 66% (43 of 65) were identified as G. duodenalis assemblage A and 34% (22 of 65) as assemblage B. Further subtyping analysis based on b-giardin gene identified the presence of subtypes A2 and A3, which belong to the anthroponotic sub-assemblage AII. Data of the study suggest that anthroponotic transmission played a potential role in the transmission of giardiasis in the community. However, further genotyping and subtyping studies of specimens from humans and animals living in the same households are needed for a more definitive understanding of giardiasis transmission in Yemen.
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Affiliation(s)
- Naela A Alyousefi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Lim YAL, Mahdy MAK, Tan TK, Goh XT, Jex AR, Nolan MJ, Sharma RSK, Gasser RB. First molecular characterization of Giardia duodenalis from goats in Malaysia. Mol Cell Probes 2012; 27:28-31. [PMID: 22971518 DOI: 10.1016/j.mcp.2012.08.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 08/14/2012] [Accepted: 08/15/2012] [Indexed: 11/16/2022]
Abstract
In the present study, 310 faecal samples from goats from eight different farms in Malaysia were tested for the presence of Giardia using a PCR-coupled approach. The nested PCR for SSU amplified products of the expected size (∼200 bp) from 21 of 310 (6.8%) samples. Sixteen of these 21 products could be sequenced successfully and represented six distinct sequence types. Phylogenetic analysis of the SSU sequence data using Bayesian Inference (BI) identified Giardia assemblages A, B and E. The identification of the 'zoonotic' assemblages A and B suggests that Giardia-infected goats represent a possible reservoir for human giardiasis in Malaysia.
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Affiliation(s)
- Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Atroosh WM, Al-Mekhlafi HM, Mahdy MAK, Surin J. The detection of pfcrt and pfmdr1 point mutations as molecular markers of chloroquine drug resistance, Pahang, Malaysia. Malar J 2012; 11:251. [PMID: 22853645 PMCID: PMC3493286 DOI: 10.1186/1475-2875-11-251] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 07/23/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria is still a public health problem in Malaysia with chloroquine (CQ) being the first-line drug in the treatment policy of uncomplicated malaria. There is a scarcity in information about the magnitude of Plasmodium falciparum CQ resistance. This study aims to investigate the presence of single point mutations in the P. falciparum chloroquine-resistance transporter gene (pfcrt) at codons 76, 271, 326, 356 and 371 and in P. falciparum multi-drug resistance-1 gene (pfmdr1) at codons 86 and 1246, as molecular markers of CQ resistance. METHODS A total of 75 P. falciparum blood samples were collected from different districts of Pahang state, Malaysia. Single nucleotide polymorphisms in pfcrt gene (codons 76, 271, 326, 356 and 371) and pfmdr1 gene (codons 86 and 1246) were analysed by using mutation-specific nested PCR and restriction fragment length polymorphism (PCR-RFLP) methods. RESULTS Mutations of pfcrt K76T and pfcrt R371I were the most prevalent among pfcrt gene mutations reported by this study; 52% and 77%, respectively. Other codons of the pfcrt gene and the positions 86 and 1246 of the pfmdr1 gene were found mostly of wild type. Significant associations of pfcrt K76T, pfcrt N326S and pfcrt I356T mutations with parasitaemia were also reported. CONCLUSION The high existence of mutant pfcrt T76 may indicate the low susceptibility of P. falciparum isolates to CQ in Peninsular Malaysia. The findings of this study establish baseline data on the molecular markers of P. falciparum CQ resistance, which may help in the surveillance of drug resistance in Peninsular Malaysia.
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Affiliation(s)
- Wahib M Atroosh
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
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Mahdy MAK, Lim YAL, Ngui R, Siti Fatimah MR, Choy SH, Yap NJ, Al-Mekhlafi HM, Ibrahim J, Surin J. Prevalence and zoonotic potential of canine hookworms in Malaysia. Parasit Vectors 2012; 5:88. [PMID: 22564445 PMCID: PMC3461414 DOI: 10.1186/1756-3305-5-88] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 05/07/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Canine hookworm infection is endemic in Southeast Asian countries with a prevalence ranging from 70% to 100%, with zoonotic transmission representing a potentially significant public health concern. However, there are limited data available on the prevalence of canine hookworms in Malaysia. This study was conducted to determine the prevalence of hookworm and Ancylostoma species among dogs in Malaysia. METHODS Faecal samples were collected from 221 dogs living in urban areas, rural areas and animal shelters in Selangor. Faecal samples were processed using the formal-ether concentration technique followed by wet mount preparation and iodine staining for the detection of hookworm eggs. Samples positive for hookworm eggs were examined using PCR, targeting ITS2 and 28 s rRNA region, and subsequently sequenced in both directions. The sequences were phylogenetically analysed using MrBayes for Bayesian Inference. RESULTS The overall prevalence of hookworm among dogs was 48% (95%CI; 41.41-54.95). Rural stray dogs had the highest prevalence 71.4% (95%CI; 61.13-81.49) followed by urban stray dogs, recording 48% (95%CI; 34.15-61.85) and lastly dogs in shelters with 28.7% (95%CI; 19.56-37.84). Logistic regression identified rural stray dogs as a high risk group (OR = 4.55, 95%; 2.50-8.31) and keeping dogs in shelters as a protective factor (OR = 0.24, 95%; 0.14-0.43). Molecular methods identified both Ancylostoma ceylanicum and Ancylostoma caninum with A. ceylanicum being predominant among urban stray dogs. Rural dogs had a higher prevalence of A. caninum than A. ceylanicum, while both species showed equal distribution among dogs in shelters. Phylogenetic analysis placed A. ceylanicum isolated from dogs in one group with A. ceylanicum human isolates. CONCLUSION This study indicates that dogs have the potential to act as reservoir hosts of human hookworm infection in Malaysia. This finding necessitates the inclusion of dogs in any interventions to combat hookworm in the country.
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Affiliation(s)
- Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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Al-Mekhlafi HM, Mahdy MAK, 'Azlin MY, Fatmah MS, Norhayati M. Childhood Cryptosporidium infection among aboriginal communities in Peninsular Malaysia. Ann Trop Med Parasitol 2011; 105:135-43. [PMID: 21396250 DOI: 10.1179/136485911x12899838683368] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Cryptosporidium is a coccidian parasite that is prevalent worldwide, some species of which cause morbidity in both immunocompromised and immunocompetent individuals. The prevalence and predictors of Cryptosporidium infection, and its effect on nutritional status, have recently been explored among 276 children (141 boys and 135 girls, aged 2-15 years) in aboriginal (Orang Asli) villages in the Malaysian state of Selangor. Faecal smears were examined by the modified Ziehl-Neelsen staining technique while socio-economic data were collected using a standardized questionnaire. Nutritional status was assessed by anthropometric measurements. Cryptosporidium infection, which was detected in 7.2% of the aboriginal children, was found to be significantly associated with low birthweight (≤2.5 kg), being part of a large household (with more than seven members) and prolonged breast feeding (>2 years). The output of a binary logistic regression confirmed that large household size was a significant predictor of Cryptosporidium infection (giving an odds ratio of 2.15, with a 95% confidence interval of 1.25-5.02). Cryptosporidium infection is clearly a public-health problem among the aboriginal children of Selangor, with person-to-person the most likely mode of transmission.
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Affiliation(s)
- H M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.
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Alyousefi NA, Mahdy MAK, Mahmud R, Lim YAL. Factors associated with high prevalence of intestinal protozoan infections among patients in Sana'a City, Yemen. PLoS One 2011; 6:e22044. [PMID: 21789210 PMCID: PMC3138770 DOI: 10.1371/journal.pone.0022044] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Accepted: 06/14/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Intestinal protozoan diseases in Yemen are a significant health problem with prevalence ranging from 18% to 27%. The present study is a cross-sectional study aimed at determining the factors associated with the high prevalence of intestinal protozoan infections among patients seeking health care in Sana'a City, the capital of Yemen. METHODOLOGY/PRINCIPAL FINDINGS Stool samples were collected from 503 patients aged between 1 and 80 years old; 219 were males and 284 females. Biodata were collected via pretested standard questionnaire. Faecal samples were processed and examined for (oo)cysts or ova using a wet mount preparation after formal-ether concentration technique. Cryptosporidium oocysts were detected using the Ziehl-Neelsen staining technique. The overall prevalence of intestinal protozoan infections was 30.9%. Infection rates of Giardia duodenalis, Entamoeba histolytica/dispar and Cryptosporidium were 17.7%, 17.1% and 1%, respectively. Other parasites detected included Ascaris lumbricoides (2.4%), Schistosoma mansoni (0.3%), Hymenolepis nana (1.4%) and Enterobius vermicularis (0.4%). Multivariate analysis using forward stepwise logistic regression based on intestinal protozoan infections showed that contact with animals (OR = 1.748, 95% CI = 1.168-2.617) and taking bath less than twice a week (OR = 1.820, 95% CI = 1.192-2.779) were significant risk factors of protozoan infections. CONCLUSIONS/SIGNIFICANCE This present study indicated that intestinal protozoan infections are still a public health problem in Yemen, with Giardia and Entamoeba infections being most common. Statistical analysis indicated that low personal hygiene and contact with animals were important predictors for intestinal protozoan infections. As highlighted in this study, in order to effectively reduce these infections, a multi-sectoral effort is needed. Preventive measures should include good hygienic practices, good animal husbandry practices, heightened provision of educational health programs, health services in all governorates including rural areas. Furthermore, it is also essential to find radical solutions to the recent water crises in Yemen.
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Affiliation(s)
- Naelah A. Alyousefi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohammed A. K. Mahdy
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Department of Parasitology, Faculty of Medicine, Sana'a University, Sana'a, Yemen
| | - Rohela Mahmud
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yvonne A. L. Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Al-Mekhlafi AM, Mahdy MAK, Al-Mekhlafi HM, Azazy AA, Fong MY. High frequency of Plasmodium falciparum chloroquine resistance marker (pfcrt T76 mutation) in Yemen: an urgent need to re-examine malaria drug policy. Parasit Vectors 2011; 4:94. [PMID: 21619624 PMCID: PMC3125383 DOI: 10.1186/1756-3305-4-94] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 05/27/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria remains a significant health problem in Yemen with Plasmodium falciparum being the predominant species which is responsible for 90% of the malaria cases. Despite serious concerns regarding increasing drug resistance, chloroquine is still used for the prevention and treatment of malaria in Yemen. This study was carried out to determine the prevalence of choloroquine resistance (CQR) of P. falciparum isolated from Yemen based on the pfcrt T76 mutation. METHODS A cross-sectional study was carried out among 511 participants from four governorates in Yemen. Blood samples were screened using microscopic and species-specific nested PCR based on the 18S rRNA gene to detect and identify Plasmodium species. Blood samples positive for P. falciparum were used for detecting the pfcrt T76 mutation using nested-PCR. RESULTS The prevalence of pfcrt T76 mutation was 81.5% (66 of 81 isolates). Coastal areas/foothills had higher prevalence of pfcrt T76 mutation compared to highland areas (90.5% vs 71.8%) (p = 0.031). The pfcrt T76 mutation had a significant association with parasitaemia (p = 0.045). Univariate analysis shows a significant association of pfcrt T76 mutation with people aged > 10 years (OR = 9, 95% CI = 2.3 - 36.2, p = 0.001), low household income (OR = 5, 95% CI = 1.3 - 19.5, p = 0.027), no insecticide spray (OR = 3.7, 95% CI = 1.16 - 11.86, p = 0.025) and not sleeping under insecticide treated nets (ITNs) (OR = 4.8, 95% CI = 1.38 - 16.78, p = 0.01). Logistic regression model confirmed age > 10 years and low household income as predictors of pfcrt T76 mutation in Yemen P. falciparum isolates. CONCLUSIONS The high prevalence of pfcrt T76 mutation in Yemen could be a predictive marker for the prevalence of P. falciparum CQR. This finding shows the necessity for an in-vivo therapeutic efficacy test for CQ. P. falciparum CQR should be addressed in the national strategy to control malaria.
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Al-Mekhlafi AM, Al-Mekhlafi HM, Mahdy MAK, Azazy AA, Fong MY. Human malaria in the highlands of Yemen. Ann Trop Med Parasitol 2011; 105:187-95. [PMID: 21801497 PMCID: PMC4090792 DOI: 10.1179/136485911x12987676649421] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Revised: 02/08/2011] [Accepted: 02/10/2011] [Indexed: 12/28/2022]
Abstract
Between June 2008 and March 2009, a cross-sectional study of human malaria was carried out in four governorates of Yemen, two (Taiz and Hodiedah) representing the country's highlands and the others (Dhamar and Raymah) the country's coastal plains/foothills. The main aims were to determine the prevalences of Plasmodium infection among 455 febrile patients presenting for care at participating health facilities and to investigate the potential risk factors for such infection. Malarial infection was detected in 78 (17·1%) of the investigated patients and was more likely to be detected among the febrile patients from the highlands than among those presenting in the coastal plains/foothills (22·6% v.13·9%; χ(2)=10·102; P=0·018). Binary logistic-regression models identified low household income [odds ratio (OR)=13·52; 95% confidence interval (CI)=2·62-69·67; P=0·002], living in a household with access to a water pump (OR=4·18; CI=1·60-10·96; P=0·004) and living in a household near a stream (OR=4·43; CI=1·35-14·56; P=0·014) as significant risk factors for malarial infection in the highlands. Low household income was the only significant risk factor identified for such infection in the coastal plains and foothills (OR = 8·20; CI=1·80-37·45; P=0·007). It is unclear why febrile patients in the highlands of Yemen are much more likely to be found to have malarial infection than their counterparts from the coastal plains and foothills. Although it is possible that malarial transmission is relatively intense in the highlands, it seems more likely that, compared with those who live at lower altitudes, those who live in the highlands are less immune to malaria, and therefore more likely to develop febrile illness following malarial infection. Whatever the cause of the symptomatic malarial infection commonly found in the highlands of Yemen, it is a matter of serious concern that should be addressed in the national strategy to control malaria.
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Al-Mekhlafi HM, Surin J, Sallam AA, Abdullah AW, Mahdy MAK. Giardiasis and poor vitamin A status among aboriginal school children in rural Malaysia. Am J Trop Med Hyg 2010; 83:523-7. [PMID: 20810815 DOI: 10.4269/ajtmh.2010.09-0371] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A cross-sectional study was carried out on 241 primary schoolchildren in Pahang, Malaysia to update their vitamin A status and to investigate the association of poor vitamin A status with their health and socioeconomic factors. All children were screened for intestinal parasitic infections. Blood samples were collected and vitamin A status was assessed. Socioeconomic data were collected by using pre-tested questionnaires. The results showed that 66 (27.4%) children had low serum retinol levels (< 0.70 micromol/L). Giardiasis and severe ascariasis were significantly associated with low serum retinol levels (P = 0.004 and P = 0.018, respectively). Logistic regression confirmed the significant association of giardiasis with low serum retinol (odds ratio = 2.7, 95% confidence interval = 1.3-5.5). In conclusion, vitamin A deficiency is still a public health problem in rural Malaysia. Vitamin A supplementation and treatment of intestinal parasitic infections should be distributed periodically to these children to improve their health and nutritional status.
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Affiliation(s)
- Hesham M Al-Mekhlafi
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
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Mahdy MAK, Al-Mekhlafi HM, Al-Mekhlafi AM, Lim YAL, Bin Shuaib NOM, Azazy AA, Mahmud R. Molecular characterization of Leishmania species isolated from cutaneous leishmaniasis in Yemen. PLoS One 2010; 5. [PMID: 20862227 PMCID: PMC2942841 DOI: 10.1371/journal.pone.0012879] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Accepted: 08/28/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Cutaneous leishmaniasis (CL) is a neglected tropical disease endemic in the tropics and subtropics with a global yearly incidence of 1.5 million. Although CL is the most common form of leishmaniasis, which is responsible for 60% of DALYs lost due to tropical-cluster diseases prevalent in Yemen, available information is very limited. METHODOLOGY/PRINCIPAL FINDINGS This study was conducted to determine the molecular characterization of Leishmania species isolated from human cutaneous lesions in Yemen. Dermal scrapes were collected and examined for Leishmania amastigotes using the Giemsa staining technique. Amplification of the ribosomal internal transcribed spacer 1(ITS-1) gene was carried out using nested PCR and subsequent sequencing. The sequences from Leishmania isolates were subjected to phylogenetic analysis using the neighbor-joining and maximum parsimony methods. The trees identified Leishmania tropica from 16 isolates which were represented by two sequence types. CONCLUSIONS/SIGNIFICANCE The predominance of the anthroponotic species (i.e. L. tropica) indicates the probability of anthroponotic transmission of cutaneous leishmaniasis in Yemen. These findings will help public health authorities to build an effective control strategy taking into consideration person-to-person transmission as the main dynamic of transmission of CL.
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Affiliation(s)
- Mohammed A K Mahdy
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
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Lim YAL, Lai MM, Mahdy MAK, Mat Naim HR, Smith HV. Molecular detection of Giardia contamination in water bodies in a zoo. Environ Res 2009; 109:857-859. [PMID: 19664767 DOI: 10.1016/j.envres.2009.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Revised: 07/07/2009] [Accepted: 07/20/2009] [Indexed: 05/28/2023]
Abstract
We used a combined microscopy-molecular approach to determine the occurrence and identities of waterborne Giardia sp. cysts isolated from 18 separate, 10l grab samples collected from a Malaysian zoo. Microscopy revealed that 17 of 18 samples were Giardia cyst positive with concentrations ranging from 1 to 120 cysts/l. Nine (52.9%) of the 17 cyst positive samples produced amplicons of which 7 (77.8%) could be sequenced. Giardia duodenalis assemblage A (6 of 7) and assemblage B (1 of 7), both infectious to humans, were identified at all sampling sites at the zoo. The presence of human infectious cysts raises public health issues, and their occurrence, abundance and sources should be investigated further. In this zoo setting, our data highlight the importance of incorporating environmental sampling (monitoring) in addition to routine faecal examinations to determine veterinary and public health risks, and water monitoring should be considered for inclusion as a separate element in hazard analysis, as it often has a historical (accumulative) connotation.
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Affiliation(s)
- Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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