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Kumar G, Gupta SK, Rahi M, Sharma A. Challenges in Understanding the Bionomics of Indian Malaria Vectors. Am J Trop Med Hyg 2022; 107:1005-1014. [PMID: 36096410 PMCID: PMC9709009 DOI: 10.4269/ajtmh.22-0137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 06/30/2022] [Indexed: 11/07/2022] Open
Abstract
Many factors influence the success or failure of malaria vector control program such as political will, leadership, sustained funding, robustness of healthcare system and others. In addition, updated knowledge and information about the triad of host, parasite, and vector is of paramount importance. Vector bionomics studies that determine mosquito behavior in terms of feeding, resting, biting, mating, breeding, longevity, vectorial capacity, and response to different insecticides are a step towards enhancing our understanding. In the present work, we have compiled studies conducted in India over the past two decades (2000-2020) to identify gaps in our knowledge of malaria vector bionomics and the research that needs to be done in the future. We retrieved district-level data of India's six primary malaria vector species. According to our findings, vector bionomics studies have been undertaken in ∼50% and ∼15% of the country's high (annual parasite index > 1) and low (annual parasite index < 1) malaria-endemic districts respectively. Most of the research studies focused on mosquito density, insecticide susceptibility status, and parasite detection, whereas other vital bionomics parameters were neglected. Surveys conducted were incomplete, and vector bionomics data were not captured sufficiently. The absence of vector bionomics data can be a blind spot and the lack or inadequate understanding of vector bionomics can lead to use of inappropriate vector control tools. Thus, there is an urgent need to initiate comprehensive bionomics studies on India's primary and secondary malaria vectors.
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Affiliation(s)
- Gaurav Kumar
- National Institute of Malaria Research, New Delhi, India
| | | | - Manju Rahi
- National Institute of Malaria Research, New Delhi, India
- Indian Council of Medical Research, New Delhi, India
| | - Amit Sharma
- National Institute of Malaria Research, New Delhi, India
- Molecular Medicine Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
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Shankar H, Singh MP, Hussain SSA, Phookan S, Singh K, Mishra N. Epidemiology of malaria and anemia in high and low malaria-endemic North-Eastern districts of India. Front Public Health 2022; 10:940898. [PMID: 35968433 PMCID: PMC9366887 DOI: 10.3389/fpubh.2022.940898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Anemia and malaria are the two major public health problems that lead to substantial morbidity and mortality. Malaria infection destroys erythrocytes, resulting in low hemoglobin (Hb) levels known as anemia. Here we report the determinants of anemia in high and low malaria-endemic areas that would help understand which parasite densities, age, and gender-associated low Hb levels. Therefore, a cross-sectional mass survey (n = 8,233) was conducted to screen anemia and malaria in high and low malaria-endemic districts (HMED and LMED) of North-East India. Axillary body temperature was measured using a digital thermometer. The prevalence of anemia was found to be 55.3% (4,547/8,233), of which 45.1% had mild (2,049/4,547), 52.1% moderate (2,367/4,547) and 2.9% had severe anemia (131/4,547). Among anemic, 70.8% (3,219/4,547) resided in LMED and the rest in HMED. The median age of the anemic population was 12 years (IQR: 7–30). Overall, malaria positivity was 8.9% (734/8,233), of which HMED shared 79.6% (584/734) and LMED 20.4% (150/734) malaria burden. The village-wise malaria frequency was concordant to asymptomatic malaria (10–20%), which showed that apparently all of the malaria cases were asymptomatic in HMED. LMED population had significantly lower Hb than HMED [standardized beta (β) = −0.067, p < 0.0001] and low-density Plasmodium infections had higher Hb levels than high-density infections (β = 0.113; p = 0.031). Women of reproductive age had higher odds for malaria (OR: 1.42; 95% CI: 1.00–2.05; p = 0.04). Females (β = −0.193; p < 0.0001) and febrile individuals (β = −0.029; p = 0.008) have shown lower Hb levels, but malaria positivity did not show any effect on Hb. Young children and women of reproductive age are prone to anemia and malaria. Although there was no relation between malaria with the occurrence of anemia, we found low-density Plasmodium infections, female gender, and LMED were potential determinants of Hb.
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Affiliation(s)
- Hari Shankar
- ICMR-National Institute of Malaria Research, New Delhi, India
- Indian Council of Medical Research, New Delhi, India
| | | | | | - Sobhan Phookan
- ICMR-National Institute of Malaria Research Field Unit, Guwahati, India
| | - Kuldeep Singh
- ICMR-National Institute of Malaria Research Field Unit, Guwahati, India
| | - Neelima Mishra
- ICMR-National Institute of Malaria Research, New Delhi, India
- *Correspondence: Neelima Mishra
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Passah M, Nengnong CB, Wilson ML, Carlton JM, Kharbamon L, Albert S. Implementation and acceptance of government-sponsored malaria control interventions in Meghalaya, India. Malar J 2022; 21:200. [PMID: 35739533 PMCID: PMC9223263 DOI: 10.1186/s12936-022-04223-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 06/09/2022] [Indexed: 11/19/2022] Open
Abstract
Background India has made considerable progress in malaria reduction over the past two decades, with government-sponsored indoor residual spraying (IRS) and insecticide-treated bed net (ITN) or long-lasting insecticidal nets (LLIN) distribution being the main vector-related prevention efforts. Few investigations have used non-participant observational methods to assess malaria control measures while they were being implemented, nor documented people’s perceptions and acceptance of IRS or LLINs in India, and none have done so in the northeast region. This study evaluated household (HH)-level operation of IRS and distribution of LLINs by India’s National Vector Borne Disease Control Programme (NVBDCP) in 50 villages of Meghalaya state, and documented their acceptance and use. Methods Study field teams accompanied the government health system teams during August-October, 2019 and 2020 to observe deployment of LLINs, and record HH-level data on LLIN numbers and use. In addition, NVBDCP spray teams were followed during 2019–2021 to observe IRS preparation and administration. HH members were interviewed to better understand reasons for acceptance or refusal of spraying. Results A total of 8386 LLINs were distributed to 2727 HHs in 24 villages from five Primary Health Centres, representing 99.5% of planned coverage. Interviews with 80 HH residents indicated that they appreciated the LLIN dissemination programme, and generally made regular and appropriate use of LLINs, except during overnight travel or when working in agricultural fields. However, HH-level IRS application, which was observed at 632 HHs, did not always follow standard insecticide preparation and safety protocols. Of 1,079 occupied HHs visited by the spray team, 632 (58.6%) refused to allow any spraying. Only 198 (18.4%) HHs agreed to be sprayed, comprising 152 (14.1%) that were only partly sprayed, and 46 (4.3%) that were fully sprayed. Reasons for refusal included: inadequate time to rearrange HH items, young children were present, annoying smell, staining of walls, and threat to bee-keeping or Eri silk moth cultivation. Conclusions These findings are among the first in India that independently evaluate people's perceptions and acceptance of ongoing government-sponsored IRS and LLIN programmes for malaria prevention. They represent important insights for achieving India's goal of malaria elimination by 2030.
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Affiliation(s)
- Mattimi Passah
- Indian Institute of Public Health Shillong, Shillong, Meghalaya, 793001, India. .,Martin Luther Christian University, Shillong, Meghalaya, 793006, India.
| | - Carinthia Balabet Nengnong
- Indian Institute of Public Health Shillong, Shillong, Meghalaya, 793001, India.,Martin Luther Christian University, Shillong, Meghalaya, 793006, India
| | - Mark L Wilson
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Jane M Carlton
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, 10003, USA.,Department of Epidemiology, College of Global Public Health, New York University, New York, NY, 10012, USA
| | - Larry Kharbamon
- Department of Health, National Vector Borne Disease Control Programme, Shillong, Meghalaya, India
| | - Sandra Albert
- Indian Institute of Public Health Shillong, Shillong, Meghalaya, 793001, India. .,Martin Luther Christian University, Shillong, Meghalaya, 793006, India.
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Dev V, Manguin S. Defeating malaria in the North-East region: the forerunner for malaria elimination in India. Acta Trop 2021; 222:106040. [PMID: 34252384 DOI: 10.1016/j.actatropica.2021.106040] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/02/2021] [Accepted: 07/03/2021] [Indexed: 11/30/2022]
Abstract
India is a malaria endemic country which is targeting malaria elimination by 2027. Transmission intensities are low-to-moderate depending on the region supported by multiple disease vectors. Among these, comparatively North-East India contributes to high proportions of malaria cases annually, the majority of which are due to Plasmodium falciparum (90%). Anopheles minimus and An. baimaii (sibling species in the An. dirus complex) are widely prevalent and incriminated as vectors of malaria. Number of intervention tools were field-evaluated beginning 1988 to date against disease vectors and causative parasites to contain the spread of malaria. These included (i) insecticide-treated netting materials (ITNs) for vector control, (ii) rapid diagnostic tests (RDTs) for in situ diagnosis, and (iii) therapeutic efficacy of artemisinin-based combination therapies (ACTs) for improved drug-policy; all of which were incorporated in healthcare services resulting in substantial disease transmission reduction. Populations of both An. minimus and An. baimaii were observed depleting, instead An. culicifacies s.l. recorded to be fast invading degraded forests and assessed to be resistant to multiple insecticides. Of the two prevalent Plasmodium species, while P. vivax continued to be susceptible to chloroquine therapy, P. falciparum had emerged resistant to most available antimalarial drugs except ACTs over space and time and spreading to peninsular India threatening elimination efforts. Disease transmission trends were observed to be declining for which the state of Assam has made huge strides reporting steady fall in cases each passing year vis-à-vis Meghalaya, Mizoram and Tripura (all sharing international border with Bangladesh), in which malaria transmission remained uninterrupted. Consequently, control of malaria in the North-East region of India is of immediate importance and needs prioritization for intensified disease surveillance and control interventions coupled with improved access to healthcare services mitigating risk of disease outbreaks and spread of drug-resistant malaria helping realize the goal of malaria elimination in the country.
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Affiliation(s)
- Vas Dev
- ICMR, National Institute of Malaria Research, New Delhi, 110 077, India
| | - Sylvie Manguin
- HydroSciences Montpellier (HSM), University Montpellier, CNRS, IRD, 34093 Montpellier, France.
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Hii J, Hustedt J, Bangs MJ. Residual Malaria Transmission in Select Countries of Asia-Pacific Region: Old Wine in a New Barrel. J Infect Dis 2021; 223:S111-S142. [PMID: 33906222 PMCID: PMC8079134 DOI: 10.1093/infdis/jiab004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Background Despite substantial reductions in malaria burden and improvement in case management, malaria remains a major public health challenge in the Asia-Pacific region. Residual malaria transmission (RMT) is the fraction of total transmission that persists after achievement of full operational coverage with effective insecticide-treated bed nets (ITNs)/long-lasting insecticidal nets (LLINs) and/or indoor residual spray interventions. There is a critical need to standardize and share best practices for entomological, anthropological, and product development investigative protocols to meet the challenges of RMT and elimination goals. Methods A systematic review was conducted to describe when and where RMT is occurring, while specifically targeting ownership and usage of ITN/LLINs, indoor residual spray application, insecticide susceptibility of vectors, and human and vector biting behavior, with a focus on nighttime activities. Results Sixty-six publications from 1995 to present met the inclusion criteria for closer review. Associations between local vector control coverage and use with behaviors of human and mosquito vectors varied by locality and circumstance. Consequently, the magnitude of RMT is insufficiently studied and analyzed with sparse estimates of individual exposure in communities, insufficient or incomplete observations of ITN/LLIN use, and the local human population movement into and from high-risk areas. Conclusions This review identified significant gaps or deficiencies that require urgent attention, namely, developing standardized procedures and methods to estimate risk exposure beyond the peridomestic setting, analytical approaches to measure key human-vector interactions, and seasonal location-specific agricultural or forest use calendars, and establishing the collection of longitudinal human and vector data close in time and location.
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Affiliation(s)
- Jeffrey Hii
- Malaria Consortium Asia, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia
| | | | - Michael J Bangs
- Public Health and Malaria Control Department, PT Freeport Indonesia, International SOS, Jl. Kertajasa, Kuala Kencana, Papua, Indonesia.,Department of Entomology, Faculty of Agriculture, Kasertart University, Bangkok, Thailand
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Shankar H, Phookan S, Singh MP, Bharti RS, Ahmed N, Yadav CP, Sharma GP, Singh K, Kaur H, Mishra N. Asymptomatic low-density Plasmodium infection during non-transmission season: a community-based cross-sectional study in two districts of North Eastern Region, India. Trans R Soc Trop Med Hyg 2021; 115:1198-1206. [PMID: 33580962 DOI: 10.1093/trstmh/trab017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 05/25/2020] [Accepted: 01/19/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Malaria elimination requires targeting asymptomatic and low-density Plasmodium infections that largely remain undetected. Therefore we conducted a cross-sectional study to estimate the burden of asymptomatic and low-density Plasmodium infection using conventional and molecular diagnostics. METHODS A total of 9118 participants, irrespective of age and sex, were screened for malaria using rapid diagnostic tests (RDTs), microscopy and polymerase chain reaction. RESULTS Among the participants, 707 presented with symptoms and 8411 without symptoms, of which Plasmodium was present in 15.6% (110/707) and 8.1% (681/8411), respectively. Low-density infection was found in 5.1% (145/2818) of participants and 8327 of 9118 were Plasmodium negative. Endemicity was propotional to asymptomatic infections (high endemicity 11.1% [404/3633] vs low endemicity 5.8% [277/4778]; odds ratio [OR] 2.0 [95% confidence interval {CI} 1.7 to 2.4]) but inversely related to low-density infection (high endemicity 3.7% [57/1545] vs low endemicity 6.9% [88/1273]; OR 1.9 [95% CI 1.4 to 2.7]). The spleen rate in children 2-9 y of age was 17.9% (602/3368) and the enlarged spleen index was 1.6. Children between 8 and 14 y showed higher odds for asymptomatic (adjusted OR [aOR] 1.75 [95% CI 1.4 to 2.2]) and low-density infections (aOR 0.63 [95% CI 0.4 to 1.0)] than adults. CONCLUSIONS The prevalence of asymptomatic and low-density Plasmodium infection undermines the usefulness of standard diagnostic tools used by health agencies. This necessitates deploying molecular tools in areas where malaria microscopy/RDTs indicate a dearth of infection.
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Affiliation(s)
- Hari Shankar
- Indian Council of Medical Research-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi 110077, India
| | - Sobhan Phookan
- Indian Council of Medical Research-National Institute of Malaria Research Field Unit, Guwahati 781022, Assam, India
| | - Mrigendra Pal Singh
- Indian Council of Medical Research-National Institute of Malaria Research Field Unit, Jabalpur 482003, Madhya Pradesh, India
| | - Ram Suresh Bharti
- Indian Council of Medical Research-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi 110077, India
| | - Naseem Ahmed
- Indian Council of Medical Research-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi 110077, India
| | - Chander Prakash Yadav
- Indian Council of Medical Research-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi 110077, India
| | - Guru Prasad Sharma
- Indian Council of Medical Research-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi 110077, India
| | - Kuldeep Singh
- Indian Council of Medical Research-National Institute of Malaria Research Field Unit, Guwahati 781022, Assam, India
| | - Harpreet Kaur
- Indian Council of Medical Research, Ansari Nagar, New Delhi 110029, India
| | - Neelima Mishra
- Indian Council of Medical Research-National Institute of Malaria Research, Sector-8, Dwarka, New Delhi 110077, India
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Sinha I, Sayeed AA, Uddin D, Wesolowski A, Zaman SI, Faiz MA, Ghose A, Rahman MR, Islam A, Karim MJ, Saha A, Rezwan MK, Shamsuzzaman AKM, Jhora ST, Aktaruzzaman MM, Chang HH, Miotto O, Kwiatkowski D, Dondorp AM, Day NPJ, Hossain MA, Buckee C, Maude RJ. Mapping the travel patterns of people with malaria in Bangladesh. BMC Med 2020; 18:45. [PMID: 32127002 PMCID: PMC7055101 DOI: 10.1186/s12916-020-1512-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 02/05/2020] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Spread of malaria and antimalarial resistance through human movement present major threats to current goals to eliminate the disease. Bordering the Greater Mekong Subregion, southeast Bangladesh is a potentially important route of spread to India and beyond, but information on travel patterns in this area are lacking. METHODS Using a standardised short survey tool, 2090 patients with malaria were interviewed at 57 study sites in 2015-2016 about their demographics and travel patterns in the preceding 2 months. RESULTS Most travel was in the south of the study region between Cox's Bazar district (coastal region) to forested areas in Bandarban (31% by days and 45% by nights), forming a source-sink route. Less than 1% of travel reported was between the north and south forested areas of the study area. Farmers (21%) and students (19%) were the top two occupations recorded, with 67 and 47% reporting travel to the forest respectively. Males aged 25-49 years accounted for 43% of cases visiting forests but only 24% of the study population. Children did not travel. Women, forest dwellers and farmers did not travel beyond union boundaries. Military personnel travelled the furthest especially to remote forested areas. CONCLUSIONS The approach demonstrated here provides a framework for identifying key traveller groups and their origins and destinations of travel in combination with knowledge of local epidemiology to inform malaria control and elimination efforts. Working with the NMEP, the findings were used to derive a set of policy recommendations to guide targeting of interventions for elimination.
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Affiliation(s)
- Ipsita Sinha
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | | | - Didar Uddin
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
| | - Amy Wesolowski
- John Hopkins Bloomberg School of Public Health, Baltimore, USA
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, USA
| | - Sazid Ibna Zaman
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- BRAC (Building Resources Across Communities), BRAC Centre, Mohakhali, Dhaka, Bangladesh
| | - M Abul Faiz
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Dev Care Foundation, Dhaka, Bangladesh
| | - Aniruddha Ghose
- Chittagong Medical College and Hospital, Chittagong, Bangladesh
| | | | - Akramul Islam
- BRAC (Building Resources Across Communities), BRAC Centre, Mohakhali, Dhaka, Bangladesh
| | - Mohammad Jahirul Karim
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Communicable Disease Control, Directorate General of Health Services, Dhaka, Bangladesh
- Filariasis Elimination, STH Control, Dhaka, Bangladesh
| | - Anjan Saha
- National Malaria Elimination Programme, Dhaka, Bangladesh
| | - M Kamar Rezwan
- Vector-Borne Disease Control, World Health Organization, Dhaka, Bangladesh
| | | | - Sanya Tahmina Jhora
- Communicable Disease Control, Directorate General of Health Services, Dhaka, Bangladesh
| | - M M Aktaruzzaman
- Communicable Disease Control, Directorate General of Health Services, Dhaka, Bangladesh
- National Malaria Elimination Programme, Dhaka, Bangladesh
| | - Hsiao-Han Chang
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, USA
| | - Olivo Miotto
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Big Data Institute, University of Oxford, Oxford, UK
| | - Dominic Kwiatkowski
- Big Data Institute, University of Oxford, Oxford, UK
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Nicholas P J Day
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - M Amir Hossain
- Chittagong Medical College and Hospital, Chittagong, Bangladesh
| | - Caroline Buckee
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, USA
| | - Richard J Maude
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, USA
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8
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Geographic Plasmodium falciparum sarcoplasmic reticulum Ca2+ ATPase (PfSERCA) genotype diversity in India. Acta Trop 2020; 202:105095. [PMID: 31323193 DOI: 10.1016/j.actatropica.2019.105095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 11/18/2018] [Accepted: 07/15/2019] [Indexed: 11/22/2022]
Abstract
Plasmodium falciparum sarcoplasmic reticulum Ca2+ ATPase (PfSERCA) is sarcoplasmic reticulum membrane bound transporter to regulate cytosol Ca2+ ions. Ca2+ act as secondary messenger and play important role in differentiation of parasite during its life cycle. Present study is epidemiological surveillance of PfSERCA (Pf3D7_0106300) gene fragment harboring 263, 402, 431 codon to look for its single nucleotide polymorphism which is well documented to be associated with Artemisinin tolerance. Filter paper with finger pricked blood samples for Plasmodium falciparum infected uncomplicated malaria patients were obtained for region as diverse as down the longitude from east to west of India i.e. Mizoram, Tripura, Meghalaya, Jharkhand, Odhisa. There observed no mutation for codon 263 at all study sites. Mizoram showed highest PfSERCA diversity with well known SNPs of L402 V, E431 K, A438 V and novel mutations as well i.e. A338 V, S357Y, S379Y. Tripura reported highest proportion of Plasmodium isolates (18.5%) with E431 K single nucleotide polymorphism. Moving towards the west i.e. Meghalaya, Jharkhand, Odhisa showed no occurrence of most prevalent PfSERCA 431, 402 polymorphism worldwide but some novel mutations and its haplotypes. In present study, significantly increased proportion of novel PfSERCA polymorphism among children suggests the susceptibility of these Plasmodium falciparum strains to acquired immunity. Mizoram, sharing open international border with south east asia, demonstrated highest PfSERCA diversity. Spatial PfSERCA diversity from far north east India to moving towards west implies its association with antimalarial susceptibility.
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Epidemiology of Imported Malaria in Netrokona District of Bangladesh 2013-2018: Analysis of Surveillance Data. Malar Res Treat 2019; 2019:6780258. [PMID: 31312425 PMCID: PMC6595392 DOI: 10.1155/2019/6780258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/11/2019] [Accepted: 04/18/2019] [Indexed: 12/14/2022] Open
Abstract
Introduction Netrokona is one of the first phase malaria elimination targeted 8 districts of Bangladesh by 2021. The district constitutes only 7% of the population but contributes half of the malaria cases in that area. Most of the cases of that district are imported from Meghalaya State of India. The study was conducted to understand the epidemiology of these imported malaria cases for further strategy development to prevent both imported and introduced cases. Methodology The study was retrospectively conducted on the malaria cases confirmed by microscopy and/or RDT by the government and/or NGO service providers between 2013 and 2018. The information of the cases was collected from the verbal "investigation" report of individual malaria confirmed cases. The respondents of the "investigation" were either the patients or their family members. Out of the 713 cases during the study period, descriptive analysis of 626 cases (based on the completeness of "investigation form") of the district was done using MS Excel version 2016. Results Proportion of imported malaria in Netrokona district increased from 60% in 2013 to 95% in 2018 which persists throughout the year with a little seasonal fluctuation. The overall contribution of these imported cases is 93% by cross-border workers by population type and 84%, 66%, and 95% by male, labour, and tribal population considering the factors of sex, occupation, and ethnicity, respectively. Population aged between 15 and 49 years contributed 82% of these imported cases. All of these cases occurred in the internationally bordering belt with Meghalaya State of India. Species-wise distribution revealed lower P. falciparum (63%) and higher mixed (28%) infection in imported cases compared to the 71% Pf and 20% mixed infection among the indigenous infections whereas P. vivax is similar in both cases. Conclusion Imported malaria is an emerging issue that has a potential risk of increased local transmission which might be a challenge to malaria elimination in that area. Appropriate interventions targeting the cross-border workers are essential to prevent the introduced cases and subsequently avoid reestablishment when elimination of the disease is achieved.
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Kessler A, van Eijk AM, Jamir L, Walton C, Carlton JM, Albert S. Malaria in Meghalaya: a systematic literature review and analysis of data from the National Vector-Borne Disease Control Programme. Malar J 2018; 17:411. [PMID: 30400879 PMCID: PMC6219117 DOI: 10.1186/s12936-018-2563-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/01/2018] [Indexed: 01/10/2023] Open
Abstract
Background Meghalaya, one of eight states in the northeastern region of India, has been reported to carry a high malaria burden. However, malaria surveillance, epidemiology, and vector studies are sparse, and no reviews combining these topics with malaria prevention and control strategies have been published in recent years. Furthermore, no analysis of surveillance data has been published documenting the changes in epidemiology following the first distribution of long-lasting insecticidal nets (LLINs) statewide in 2016. Methods A hybrid approach was used to describe the status of malaria in Meghalaya. First, a literature search was performed using the terms ‘malaria’ and ‘Meghalaya’. Second, data were obtained from the Meghalaya State Malaria Control Programme for 2006–2017 for analysis of trends. Data from 3 years 2015–2017 were analysed further by district and year to assess changes in malaria incidence and distribution following the introduction of LLINs. Results/conclusions Like malaria in mainland India, malaria in Meghalaya is complex, with both Plasmodium falciparum and Plasmodium vivax parasites in circulation, multiple Anopheles vector species, and reports of both unusual and severe malaria syndromes across all age groups. Integrated statewide malaria epidemiology, vector, and prevention and control data for Meghalaya are not readily available, and published studies are largely focused on a single topic or a single district or region of the state. Although malaria prevention and control approaches are available, (e.g. spraying, LLINs, personal repellents), their use and effectiveness is also not well characterized in the literature. Analysis of state malaria control programme data indicates that case incidence and related fatalities in Meghalaya have declined over the last decade. This could be attributed to changes in treatment guidelines and/or statewide distribution of effective prevention methods such as LLINs. Since the distribution of more than 900,000 LLINs in 2016, the malaria caseload has declined significantly in most Meghalaya districts, excluding the remote and geographically isolated South Garo Hills. Additionally, the proportion of adult malaria cases (15+ years of age versus children 0–14 years) in most districts was significantly greater following LLIN distribution, which likely reflects common lifestyle practices in these areas (e.g. adults working during night hours; small children in the households receiving priority for bed net protection). While reduction in malaria case incidence and related deaths is clear, the changes in malaria transmission and clinical manifestation have not been characterized. Routine epidemiology and vector surveillance combined with real-time data reporting are essential for the continued reduction and eventual elimination of malaria in Meghalaya.
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Affiliation(s)
- Anne Kessler
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA
| | - Anna Maria van Eijk
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA
| | - Limalemla Jamir
- Indian Institute of Public Health-Shillong, Lawmali, Shillong, Meghalaya, India
| | | | - Jane M Carlton
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY, USA.
| | - Sandra Albert
- Indian Institute of Public Health-Shillong, Lawmali, Shillong, Meghalaya, India.,Martin Luther Christian University, Shillong, Meghalaya, India
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Goomber S, Mishra N, Anvikar A, Yadav CP, Valecha N. Spatio-temporal distribution of PfMDR1 polymorphism among uncomplicated Plasmodium falciparum malaria cases along international border of north east India. INFECTION GENETICS AND EVOLUTION 2018; 63:285-290. [PMID: 29842979 DOI: 10.1016/j.meegid.2018.05.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/22/2018] [Accepted: 05/25/2018] [Indexed: 10/16/2022]
Abstract
PfMDR1 single nucleotide polymorphisms (SNP) are good correlate markers for antimalarial drug resistance worldwide. Present study is a comprehensive view of screening of PfMDR1 polymorphism to antimalarials practiced with geography and time. Study sites Mizoram, Tripura, Meghalaya chosen are at multivariate drug pressure due to cross border migration and transmission. Mizoram is gateway to south east Asia through Myanmar whereas Tripura, Meghalaya share porous border with Bangladesh. Baseline finger pricked blood stained filter paper for confirmed uncomplicated Plasmodium falciparum infected patients (year 2015) were obtained from National Institute of Malaria Research, New Delhi, India. PfMDR1 polymorphism for codon N86Y, Y184F, D1246Y was determined by PCR-RFLP, further confirmed by sequencing. There observed marked predominance of Plasmodium isolates with PfMDR1 wild type alleles for all codons under study i.e. 86, 184, 1246. Spatially, Plasmodium isolates from Mizoram were most diverse with co-existence of PfMDR1 genotype with NYD, YYD, NFD haplotypes, followed by Tripura. Isolates from Meghalaya were of all NYD haplotype. Reports, referring to screening of PfMDR1 SNPs to CQ/SP/AS-SP across India, were archived. Temporal study show distinct rise in proportion of PfMDR1 wild type N86 allele since introduction of Artemether-Lumefantrine as first line antimalarial. Hence spatio-temporal screening of Plasmodium population with PfMDR1 single nucleotide polymorphism accounts for its association with antimalarial susceptibility and validate PfMDR1 SNPs as antimalarial drug resistant marker.
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Affiliation(s)
- Shelly Goomber
- National Institute of Malaria Research, Indian Council of Medical Research, Sector - 8, Dwarka, New Delhi, India.
| | - Neelima Mishra
- National Institute of Malaria Research, Indian Council of Medical Research, Sector - 8, Dwarka, New Delhi, India
| | - Anup Anvikar
- National Institute of Malaria Research, Indian Council of Medical Research, Sector - 8, Dwarka, New Delhi, India
| | - Chander Prakash Yadav
- National Institute of Malaria Research, Indian Council of Medical Research, Sector - 8, Dwarka, New Delhi, India
| | - Neena Valecha
- National Institute of Malaria Research, Indian Council of Medical Research, Sector - 8, Dwarka, New Delhi, India
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Sharma I, Saikia A, Chakraborty P. Epidemiology of malaria and MSP-2 gene-based genetic diversity of Plasmodium falciparum from patients attending community health centre, Jiribam, Manipur. Indian J Med Microbiol 2017; 35:410-414. [PMID: 29063888 DOI: 10.4103/ijmm.ijmm_14_532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Two millilitres of peripheral blood was collected from 323 patients of different age groups and rapid diagnosis (RDT test) was performed. Parasite genomic DNA was extracted from whole blood and MSP-2 gene-based diversity and polymorphism was determined followed by restriction fragment length polymorphism analysis using Taq 1 and Vsp 1 digestion of each polymerase chain reaction product to analyse MSP-2 genotypes. Twenty-six sequences of P. falciparum MSP-2 gene were retrieved from the current GenBank database to represent strains from various geographical locations and were analysed for the Taq 1 and Vsp 1 enzyme restriction sites using in silico restriction digestion in Sequence Manipulation Suite, Version 2.
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Affiliation(s)
- Indu Sharma
- Department of Microbiology, Assam University, Silchar, Assam, India
| | - Appu Saikia
- Department of Microbiology, Assam University, Silchar, Assam, India
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Kumar R, Dash C, Rani K. Ecological covariates based predictive model of malaria risk in the state of Chhattisgarh, India. J Parasit Dis 2017; 41:761-767. [PMID: 28848275 DOI: 10.1007/s12639-017-0885-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 01/27/2017] [Indexed: 11/28/2022] Open
Abstract
Malaria being an endemic disease in the state of Chhattisgarh and ecologically dependent mosquito-borne disease, the study is intended to identify the ecological covariates of malaria risk in districts of the state and to build a suitable predictive model based on those predictors which could assist developing a weather based early warning system. This secondary data based analysis used one month lagged district level malaria positive cases as response variable and ecological covariates as independent variables which were tested with fixed effect panelled negative binomial regression models. Interactions among the covariates were explored using two way factorial interaction in the model. Although malaria risk in the state possesses perennial characteristics, higher parasitic incidence was observed during the rainy and winter seasons. The univariate analysis indicated that the malaria incidence risk was statistically significant associated with rainfall, maximum humidity, minimum temperature, wind speed, and forest cover (p < 0.05). The efficient predictive model include the forest cover [IRR-1.033 (1.024-1.042)], maximum humidity [IRR-1.016 (1.013-1.018)], and two-way factorial interactions between district specific averaged monthly minimum temperature and monthly minimum temperature, monthly minimum temperature was statistically significant [IRR-1.44 (1.231-1.695)] whereas the interaction term has a protective effect [IRR-0.982 (0.974-0.990)] against malaria infections. Forest cover, maximum humidity, minimum temperature and wind speed emerged as potential covariates to be used in predictive models for modelling the malaria risk in the state which could be efficiently used for early warning systems in the state.
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Affiliation(s)
- Rajesh Kumar
- Child Right and You (CRY), Sayad Ul Ajab, Westend Marg, New Delhi, 110030 India
| | | | - Khushbu Rani
- Women and Child Welfare Consultant, New Delhi, India
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Yadav K, Dhiman S, Rabha B, Goswami D, Saikia PK, Veer V. Disappearance of Anopheles minimus and Anopheles dirus from Certain Malaria Endemic Areas of Assam, India. J Arthropod Borne Dis 2017; 11:27-35. [PMID: 29026850 PMCID: PMC5629303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 11/17/2015] [Indexed: 10/26/2022] Open
Abstract
BACKGROUND Orang Primary Health Centre (OPHC) and Balipara Primary Health Centre (BPHC) of Assam (India) report mosquito borne diseases annually. Current study was performed to ascertain the prevalence of known malaria and Japanese Encephalitis (JE) vectors and their possible role in disease transmission. METHODS Malaria epidemiological data for 2006-2010 and JE data for 2008-2013 of Assam, India were obtained from the health authority. Mosquitoes were collected using CDC light traps and identified morpho-taxonomically. RESULTS Plasmodium falciparum cases (81.5%, 95% CI= 72.0-91.1) were statistically higher in OPHC (P< 0.0001, t= 8.0) during the recent years. There was 4.4 folds rise in the confirmed acute encephalitis syndrome (AES) and 3.2 folds increase in the confirmed JE cases during 2013 as compared to 2008. Altogether 9,218 mosquito specimens (PTND= 153.6), comprising of 44.1% anophelines (PTND= 67.7), 42.3% culicines (PTND= 65.0) and 9.5% mansonia (PTND= 14.6) were recorded. In BPHC, Anopheles vagus was recorded in high density (P< 0.0001), whereas Culex quinquefasciatus was the predominant JE vector (P= 0.04). In OPHC, among the known malaria vectors, the density of Anopheles annularis was significantly high (P< 0.0001). However Culex bitaeniorhynchus was the predominant known JE vector (P< 0.0001) followed by Cx. quinquefasciatus. CONCLUSION Even in the absence of known efficient vectors, many Anopheles species are still involved in malaria transmission. There was disappearance of Anopheles minimus and Anopheles dirus and establishment of An. annularis, An. vagus and An. philippinensis/nivipes mosquitoes in study area.
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Affiliation(s)
- Kavita Yadav
- Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India,Corresponding author: Dr Kavita Yadav, E-mail:
| | - Sunil Dhiman
- Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India
| | - Bipul Rabha
- Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India
| | - Diganta Goswami
- Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India
| | - PK Saikia
- Zoology Department, Gauhati University, Guwahati, Assam, India
| | - Vijay Veer
- Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India
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Dev V, Manguin S. Biology, distribution and control of Anopheles (Cellia) minimus in the context of malaria transmission in northeastern India. Parasit Vectors 2016; 9:585. [PMID: 27846911 PMCID: PMC5111344 DOI: 10.1186/s13071-016-1878-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 11/07/2016] [Indexed: 11/17/2022] Open
Abstract
Among six dominant mosquito vector species involved in malaria transmission in India, Anopheles minimus is a major species in northeast India and held responsible for focal disease outbreaks characterized by high-rise of Plasmodium falciparum infections and attributable death cases. It has been now genetically characterized that among the three-member species of the Minimus Complex spread in Asia, An. minimus (former species A) is prevalent in India including northeastern states and east-central state of Odisha. It is recorded in all seasons and accounts for perennial transmission evidenced by records of sporozoite infections. This species is highly anthropophilic, and largely endophilic and endophagic, recorded breeding throughout the year in slow flowing seepage water streams. The populations of An. minimus in India are reported to be highly diverse indicating population expansion with obvious implications for judicious application of vector control interventions. Given the rapid ecological changes due to deforestation, population migration and expansion and developmental activities, there is scope for further research on the existence of potential additional sibling species within the An. minimus complex and bionomics studies on a large geographical scale for species sanitation. For control of vector populations, DDT continues to be applied on account of retaining susceptibility status even after decades of residual spraying. Anopheles minimus is a highly adaptive species and requires continuous and sustained efforts for its effective control to check transmission and spread of drug-resistant malaria. Anopheles minimus populations are reportedly diminishing in northeastern India whereas it has staged comeback in east-central State of Odisha after decades of disappearance with its eco-biological characteristics intact. It is the high time to siege the opportunity for strengthening interventions against this species for its population diminution to sub-optimal levels for reducing transmission in achieving malaria elimination by target date of 2030.
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Affiliation(s)
- Vas Dev
- National Institute of Malaria Research (Field Station), Guwahati, 781022, Assam, India
| | - Sylvie Manguin
- Institut de Recherche pour le Développement FRANCE (IRD), LIPMC, UMR-MD3, Faculté de Pharmacie, F-34093, Montpellier, France.
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Dev V, Adak T, Singh OP, Nanda N, Baidya BK. Malaria transmission in Tripura: Disease distribution & determinants. Indian J Med Res 2016; 142 Suppl:S12-22. [PMID: 26905237 PMCID: PMC4795342 DOI: 10.4103/0971-5916.176597] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND & OBJECTIVES Malaria is a major public health problem in Tripura and focal disease outbreaks are of frequent occurrence. The state is co-endemic for both Plasmodium falciparum and P. vivax and transmission is perennial and persistent. The present study was aimed to review data on disease distribution to prioritize high-risk districts, and to study seasonal prevalence of disease vectors and their bionomical characteristics to help formulate vector species-specific interventions for malaria control. METHODS Data on malaria morbidity in the State were reviewed retrospectively (2008-2012) for understanding disease distribution and transmission dynamics. Cross-sectional mass blood surveys were conducted in malaria endemic villages of South Tripura district to ascertain the prevalence of malaria and proportions of parasite species. Mosquito collections were made in human dwellings of malaria endemic villages aiming at vector incrimination and to study relative abundance, resting and feeding preferences, and their present susceptibility status to DDT. RESULTS The study showed that malaria was widely prevalent and P. falciparum was the predominant infection (>90%), the remaining were P. vivax cases. The disease distribution, however, was uneven with large concentration of cases in districts of South Tripura and Dhalai coinciding with vast forest cover and tribal populations. Both Anopheles minimus s.s. and An. baimaii were recorded to be prevalent and observed to be highly anthropophagic and susceptible to DDT. Of these, An. minimus was incriminated (sporozoite infection rate 4.92%), and its bionomical characteristics revealed this species to be largely indoor resting and endophagic. INTERPRETATION & CONCLUSIONS For effective control of malaria in the state, it is recommended that diseases surveillance should be robust, and vector control interventions including DDT spray coverage, mass distribution of insecticide-treated nets/ long-lasting insecticidal nets should be intensified prioritizing population groups most at risk to avert impending disease outbreaks and spread of drug-resistant malaria.
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Affiliation(s)
- Vas Dev
- National Institute of Malaria Research (Field Station) (ICMR), Guwahati, India
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Wangdi K, Gatton ML, Kelly GC, Banwell C, Dev V, Clements ACA. Malaria elimination in India and regional implications. THE LANCET. INFECTIOUS DISEASES 2016; 16:e214-e224. [PMID: 27527748 DOI: 10.1016/s1473-3099(16)30123-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 03/30/2016] [Accepted: 05/05/2016] [Indexed: 12/16/2022]
Abstract
The malaria situation in India is complex as a result of diverse socio-environmental conditions. India contributes a substantial burden of malaria outside sub-Saharan Africa, with the third highest Plasmodium vivax prevalence in the world. Successful malaria control in India is likely to enhance malaria elimination efforts in the region. Despite modest gains, there are many challenges for malaria elimination in India, including: varied patterns of malaria transmission in different parts of the country demanding area-specific control measures; intense malaria transmission fuelled by favourable climatic and environment factors; varying degrees of insecticide resistance of vectors; antimalarial drug resistance; a weak surveillance system; and poor national coordination of state programmes. Prevention and protection against malaria are low as a result of a weak health-care system, as well as financial and socioeconomic constraints. Additionally, the open borders of India provide a potential route of entry for artesunate-resistant parasites from southeast Asia. This situation calls for urgent dialogue around tackling malaria across borders-between India's states and neighbouring countries-through sharing of information and coordinated control and preventive measures, if we are to achieve the aim of malaria elimination in the region.
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Affiliation(s)
- Kinley Wangdi
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia; Phuentsholing General Hospital, Phuentsholing, Bhutan.
| | - Michelle L Gatton
- School of Public Health & Social Work, Queensland University of Technology, Brisbane, QLD, Australia
| | - Gerard C Kelly
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia
| | - Cathy Banwell
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia
| | - Vas Dev
- National Institute of Malaria Research (ICMR), Guwahati, Assam, India
| | - Archie C A Clements
- Research School of Population Health, College of Medicine, Biology and Environment, The Australian National University, Canberra, ACT, Australia
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18
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Dhiman S, Goswami D, Rabha B, Yadav K, Chattopadhyay P, Veer V. Absence of asymptomatic malaria in a cohort of 133 individuals in a malaria endemic area of Assam, India. BMC Public Health 2015; 15:919. [PMID: 26384971 PMCID: PMC4575429 DOI: 10.1186/s12889-015-2294-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 09/16/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria in northeast India affects children and adults annually. The number of malaria cases reported has declined over the past few years. Nevertheless, it is not clear whether there is an actual decline in parasitaemia or whether asymptomatic malaria infections are on the rise, especially in forested and forest-fringed areas. Asymptomatic malaria forms a parasite reservoir that acts as an epicentre for malaria spread during high-transmission season. Therefore it is important to understand the quantum of asymptomatic malaria infections among the vulnerable population. METHOD Four forest fringed historically malaria endemic villages were selected for the study. A total of 133 individuals without a fever history in the past four weeks were tested for malaria parasite using rapid diagnostic test (RDT), microscopy and polymerase chain reaction (PCR) assay during January - February 2014. Indoor resting Anopheles vectors were collected, identified and tested for sporozoite using VectorTest™ panel assay during October 2013 to March 2014, which is a low transmission season for malaria. Social and demographic data were recorded during the study. RESULTS Mean age (± SEM) of the participants was 16.1 ± 1.2 years (95 % CI: 13.8-18.4). All participants (100 %) reported to use mosquito nets. Altogether, 43.6 % of participants had education below primary level and only 9 % reported a travel history during the past four weeks. All RDT, microscopy and PCR assays were found negative indicating no asymptomatic malaria parasitaemia. Seven known malaria vector species namely, Anopheles nivipes, An. minimus, An. annularis, An. vagus, An. aconitus, An. philippinensis and An. culicifacies, were recorded in the present study. VectorTest™ sporozoite panel assay conducted on 45 pools (N = 224) of vector mosquitoes were found negative for Plasmodium sporozoite. DISCUSSION Northeastern states of India report asymptomatic malaria parasitemia along with high malaria transmission. An. minimus and An. dirus are recognised as efficient vectors, but An. culicifacies, An. philippinensis and An. annularis also play role in malaria transmission. Currently all participants were found negative for asymptomatic malaria, however the small sample size may restrict the scope of present results to the population living in more remote areas. CONCLUSION No cases of asymptomatic malaria infections parasitaemia was found in the present study conducted during a low transmission season indicating that asymptomatic malaria parasitaemia may not be prevalent in the region. Mosquito specimens were tested negative for the malaria sporozoites. Study findings encourage the ongoing malaria intervention efforts and recommends similar investigations in different ecological areas involving large populations.
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Affiliation(s)
- Sunil Dhiman
- Department of Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India, 784 001.
| | - Diganta Goswami
- Department of Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India, 784 001.
| | - Bipul Rabha
- Department of Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India, 784 001.
| | - Kavita Yadav
- Department of Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India, 784 001.
| | - Pronobesh Chattopadhyay
- Department of Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India, 784 001.
| | - Vijay Veer
- Department of Medical Entomology, Defence Research Laboratory, Tezpur, Assam, India, 784 001.
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Mutheneni SR, Upadhyayula SM, Kadiri MR, Nishing K. Malaria prevalence in Arunachal Pradesh--a northeastern state of India. Am J Trop Med Hyg 2014; 91:1088-93. [PMID: 25331801 DOI: 10.4269/ajtmh.14-0078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Malaria is endemic in Arunachal Pradesh, India. To understand seasonal prevalence and malaria transmission, a retrospective surveillance study was conducted from 1995 to 2012. Plasmodium vivax caused 80.8% and P. falciparum caused 17.7% of total malaria cases. It was observed that prevalence rates of P. vivax declined significantly (P < 0.001) from 1995 to 2012 but that P. falciparum remained constant during the study period (P = 0.57). The decrease in the prevalence of P. vivax cases may be because of effective implementation of vector and disease management programs. It is noted that there was a significant correlation between the number of P. falciparum malaria cases and rainfall (P < 0.06). These findings help us to understand the patterns of malaria epidemiology in Arunachal Pradesh and show that P. falciparum is circulating constantly and requires more effective control measures to combat it.
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Affiliation(s)
- Srinivasa Rao Mutheneni
- Biology Division, Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh, India; Directorate of Health Services, Naharlagun, Arunachal Pradesh, India
| | - Suryanaryana Murty Upadhyayula
- Biology Division, Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh, India; Directorate of Health Services, Naharlagun, Arunachal Pradesh, India
| | - Madhusudhan Rao Kadiri
- Biology Division, Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh, India; Directorate of Health Services, Naharlagun, Arunachal Pradesh, India
| | - Kartik Nishing
- Biology Division, Indian Institute of Chemical Technology, Hyderabad, Andhra Pradesh, India; Directorate of Health Services, Naharlagun, Arunachal Pradesh, India
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Gopalakrishnan R, Baruah I, Veer V. Monitoring of malaria, Japanese encephalitis and filariasis vectors. Med J Armed Forces India 2014; 70:129-33. [PMID: 24843200 DOI: 10.1016/j.mjafi.2013.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 10/25/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Vector monitoring in military stations would help in protecting the armed forces from vector borne diseases such as malaria, Japanese encephalitis and filariasis. METHODS Adult mosquitoes were collected from four villages around a military station in India using light traps and the species composition was estimated. Insecticide susceptibility of disease vectors against DDT, deltamethrin and permethrin was established using WHO kits. RESULTS The known malaria vectors constituted 4.9% of the total mosquito collections and Anopheles philippinensis/nivipes (2.05%) was the most abundant. Japanese encephalitis and dengue vectors constituted 25.3 and 0.05% whereas the known vectors of both Japanese encephalitis and filariasis formed 50.9%. The mean (±SEmean) of annual parasitic index, slide positivity and Plasmodium falciparum percentage among the civilian population during the study period were 1.46 ± 0.37, 1.65 ± 0.77 and 50.2 ± 10.7. The filariasis vector Culex quinquefasciatus was resistant to DDT with 65.4% mortality whereas the DDT resistance in the Japanese encephalitis vector Culex vishnui gr. with 91.9% mortality needs to be confirmed. All other species tested were susceptible to DDT, deltamethrin and permethrin. CONCLUSION Targeted interventions are needed to reduce the disease burden and vector activity in the villages adjoining the military station. The use of insect repellents, bed nets and repellent impregnated uniforms by the troops should be ensured for protection from vector borne diseases.
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Affiliation(s)
- Reji Gopalakrishnan
- Scientist 'D', Defence Research Laboratory (Defence Research & Development Organisation), PB No. 2, Tezpur 784 001, Assam, India
| | - Indra Baruah
- Scientist 'E', Defence Research Laboratory (Defence Research & Development Organisation), PB No. 2, Tezpur 784 001, Assam, India
| | - Vijay Veer
- Scientist 'G', Director, Defence Research Laboratory (Defence Research & Development Organisation), PB No. 2, Tezpur 784 001, Assam, India
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Sailo L, Pradhan D, Nongthombam R, Bhattacharyya P. Disseminated intravascular coagulation in malaria: A case report. Niger Med J 2014; 55:171-2. [PMID: 24791054 PMCID: PMC4003723 DOI: 10.4103/0300-1652.129665] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Disseminated intravascular coagulation (DIC) is seen in <5% of patients with severe Plasmodium falciparum malaria and is more common in cerebral malaria. Here, we report the diagnosis and management of a case of severe P. falciparum malaria with DIC.
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Affiliation(s)
- Laltanpuii Sailo
- Department of Anesthesiology and Critical Care, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India
| | - Debasis Pradhan
- Department of Anesthesiology and Critical Care, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India
| | - Rakesh Nongthombam
- Department of Anesthesiology and Critical Care, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India
| | - Prithwis Bhattacharyya
- Department of Anesthesiology and Critical Care, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India
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Haque U, Overgaard HJ, Clements ACA, Norris DE, Islam N, Karim J, Roy S, Haque W, Kabir M, Smith DL, Glass GE. Malaria burden and control in Bangladesh and prospects for elimination: an epidemiological and economic assessment. LANCET GLOBAL HEALTH 2014; 2:e98-105. [PMID: 25104666 DOI: 10.1016/s2214-109x(13)70176-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Malaria is endemic in 13 of 64 districts in Bangladesh. About 14 million people are at risk. Some evidence suggests that the prevalence of malaria in Bangladesh has decreased since the the Global Fund to Fight AIDS, Tuberculosis and Malaria started to support the National Malaria Control Program (NMCP) in 2007. We did an epidemiological and economic assessment of malaria control in Bangladesh. METHODS We obtained annually reported, district-level aggregated malaria case data and information about disbursed funds from the NMCP. We used a Poisson regression model to examine the associations between total malaria, severe malaria, malaria-attributable mortality, and insecticide-treated net coverage. We identified and mapped malaria hotspots using the Getis-Ord Gi* statistic. We estimated the cost-effectiveness of the NMCP by estimating the cost per confirmed case, cost per treated case, and cost per person of insecticide-treated net coverage. FINDINGS During the study period (from Jan 1, 2008, to Dec 31, 2012) there were 285,731 confirmed malaria cases. Malaria decreased from 6.2 cases per 1000 population in 2008, to 2.1 cases per 1000 population in 2012. Prevalence of all malaria decreased by 65% (95% CI 65-66), severe malaria decreased by 79% (78-80), and malaria-associated mortality decreased by 91% (83-95). By 2012, there was one insecticide-treated net for every 2.6 individuals (SD 0.20). Districts with more than 0.5 insecticide-treated nets per person had a decrease in prevalence of 21% (95% CI 19-23) for all malaria, 25% (17-32) for severe malaria, and 76% (35-91) for malaria-associated mortality among all age groups. Malaria hotspots remained in the highly endemic districts in the Chittagong Hill Tracts. The cost per diagnosed case was US$0.39 (SD 0.02) and per treated case was $0.51 (0.27); $0.05 (0.04) was invested per person per year for health education and $0.68 (0.30) was spent per person per year for insecticide-treated net coverage. INTERPRETATION Malaria elimination is an achievable prospect in Bangladesh and failure to push for elimination nearly ensures a resurgence of disease. Consistent financing is needed to avoid resurgence and maintain elimination goals. FUNDING None.
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Affiliation(s)
- Ubydul Haque
- W Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
| | - Hans J Overgaard
- Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences, Ås, Norway
| | - Archie C A Clements
- University of Queensland, Infectious Disease Epidemiology Unit, School of Population Health, Herston, QLD, Australia
| | - Douglas E Norris
- W Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Nazrul Islam
- Ministry of Health and Family Welfare, Malaria and Parasitic Disease Control, Director General of Health Services, Mohakhali, Dhaka, Bangladesh
| | - Jahirul Karim
- Ministry of Health and Family Welfare, Malaria and Parasitic Disease Control, Director General of Health Services, Mohakhali, Dhaka, Bangladesh
| | - Shyamal Roy
- Ministry of Health and Family Welfare, Malaria and Parasitic Disease Control, Director General of Health Services, Mohakhali, Dhaka, Bangladesh
| | - Waziul Haque
- Oslo and Akershus University College of Applied Sciences, Oslo, Norway
| | - Moktadir Kabir
- BRAC Health, Nutrition and Population Programme, BRAC, Dhaka, Bangladesh
| | - David L Smith
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Gregory E Glass
- W Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA; Southern Research Institute, Frederick, MD, USA
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23
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A Realistic Host-Vector Transmission Model for Describing Malaria Prevalence Pattern. Bull Math Biol 2013; 75:2499-528. [DOI: 10.1007/s11538-013-9905-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 09/19/2013] [Indexed: 01/05/2023]
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24
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Srivastava P, Ratha J, Shah NK, Mishra N, Anvikar AR, Sharma SK, Das MK, Srivastava B, Valecha N. A clinical and molecular study of artesunate + sulphadoxine-pyrimethamine in three districts of central and eastern India. Malar J 2013; 12:247. [PMID: 23866298 PMCID: PMC3726327 DOI: 10.1186/1475-2875-12-247] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 07/07/2013] [Indexed: 01/09/2023] Open
Abstract
Background Artesunate + sulphadoxine-pyrimethamine (AS + SP) is recommended throughout India as the first-line treatment for uncomplicated falciparum malaria. Due to the presence of several eco-epidemiological zones of malaria and variable drug pressure, it is necessary to evaluate the efficacy of this combination in different regions of India. The objective of this study was to use clinical and molecular methods to monitor the efficacy of AS + SP in three diverse sites. Methods The study was undertaken in three high endemic sites of central and eastern India. Patients with uncomplicated falciparum malaria were enrolled and followed for 28 days. Molecular genotyping was conducted for merozoite surface protein (msp1 and msp2) to differentiate between re-infection and recrudescence and for the dhfr and dhps genes to monitor antifolate drug resistance. Results In all, 149 patients were enrolled at the three sites. The crude cure rates were 95.9%, 100%, and 100% in Ranchi, Keonjhar, and West Garo Hills respectively. PCR-corrected cure rates were 100% at all sites. In dhfr, 27% of isolates had triple mutations, while 46% isolates were double-mutants. The most prevalent mutation was S108N followed by C59R. 164 L mutation was observed in 43/126 (34%) isolates. In dhps, most (76%) of the isolates were wild-type. Only 2.5% (2/80) isolates showed double mutation. dhfr-dhps two locus mutation were observed in 16% (13/80) isolates. Parasite clearance time was not related with antifolate mutations. Conclusions AS + SP combination therapy remained effective against falciparum malaria despite common mutations promoting resistance to antifolate drugs. Although the prevalence of double and triple mutations in dhfr was high, the prevalence of dhfr-dhps two locus mutations were low. Even isolates with dhfr triple and dhfr-dhps two locus mutations achieved adequate clinical and parasitological response.
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25
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Chemotherapy and drug resistance status of malaria parasite in northeast India. ASIAN PAC J TROP MED 2013; 6:583-8. [DOI: 10.1016/s1995-7645(13)60101-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 11/15/2012] [Accepted: 12/15/2012] [Indexed: 11/23/2022] Open
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Islam N, Bonovas S, Nikolopoulos GK. An epidemiological overview of malaria in Bangladesh. Travel Med Infect Dis 2013; 11:29-36. [PMID: 23434288 DOI: 10.1016/j.tmaid.2013.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 12/17/2012] [Accepted: 01/22/2013] [Indexed: 10/27/2022]
Abstract
Bangladesh is one of the four major malaria-endemic countries in South-East Asia having approximately 34% of its population at risk of malaria. This paper aims at providing an overview of the malaria situation in this country. Relevant information was retrieved from published articles and reports in PubMed and Google Scholar. Malaria in Bangladesh is concentrated in 13 districts with a prevalence ranging between 3.1% and 36%, and is mostly caused by Plasmodium falciparum. Geographical conditions pose a potential risk for Plasmodium knowlesi malaria. Resistance to a number of drugs previously recommended for treatment has been reported. Low socio-economic status, poor schooling and close proximity to water bodies and forest areas comprise important risk factors. Despite the significant steps in Long Lasting Insecticide Net (LLIN)/Insecticide Treated Net (ITN) coverage in Bangladesh, there are still many challenges including the extension of malaria support to the remote areas of Bangladesh, where malaria prevalence is higher, and further improvements in the field of referral system and treatment.
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Affiliation(s)
- Nazrul Islam
- Cyprus International Institute for Environmental and Public Health, Limassol, Cyprus
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Roy SB, Sarkar RR, Sinha S. Theoretical investigation of malaria prevalence in two Indian cities using the response surface method. Malar J 2011; 10:301. [PMID: 21999606 PMCID: PMC3224354 DOI: 10.1186/1475-2875-10-301] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 10/14/2011] [Indexed: 11/10/2022] Open
Abstract
Background Elucidation of the relationships between malaria incidence and climatic and non-climatic factors in a region is of utmost importance in understanding the causative factors of disease spread and design of control strategies. Very often malaria prevalence data is restricted to short time scales (months to few years). This demands application of rigorous statistical modelling techniques for analysis and prediction. The monthly malaria prevalence data for three to five years from two cities in southern India, situated in two different climatic zones, are studied to capture their dependence on climatic factors. Methods The statistical technique of response surface method (RSM) is applied for the first time to study any epidemiological data. A new step-by-step model reduction technique is proposed to refine the initial model obtained from RSM. This provides a simpler structure and gives better fit. This combined approach is applied to two types of epidemiological data (Slide Positivity Rates values and Total Malaria cases), for two cities in India with varying strengths of disease prevalence and environmental conditions. Results The study on these data sets reveals that RSM can be used successfully to elucidate the important environmental factors influencing the transmission of the disease by analysing short epidemiological time series. The proposed approach has high predictive ability over relatively long time horizons. Conclusions This method promises to provide reliable forecast of malaria incidence across varying environmental conditions, which may help in designing useful control programmes for malaria.
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Affiliation(s)
- Sayantani Basu Roy
- Centre for Cellular and Molecular Biology (CSIR), Uppal Road, Hyderabad, India
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Rabha B, Goswami D, Dhiman S, Das NG, Talukdar PK, Nath MJ, Baruah I, Bhola RK, Singh L. A cross sectional investigation of malaria epidemiology among seven tea estates in Assam, India. J Parasit Dis 2011; 36:1-6. [PMID: 23542574 DOI: 10.1007/s12639-011-0070-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 08/15/2011] [Indexed: 11/24/2022] Open
Abstract
In the present investigation, the epidemiology of malaria among seven tea estates of Nagaon and Udalguri districts of Assam, India has been described. A cross-sectional open study was carried out to understand the malaria epidemiology and associated risk factors among the tea tribes during March to September 2009. Out of 1,182 peripheral blood smears examined, 506 found positive for malaria (slide positivity rate, SPR = 42.8) with Plasmodium falciparum as predominant species. Dimakuchi tea estate was having highest SPR (P = 0.0275) and contributed more number of P. falciparum cases (P < 0.00001). Tea estates studied in both Udalguri and Nagaon districts were equally affected and the SPR recorded were 41.75 and 43.32% respectively. 154 malaria cases detected were having 'O' blood group but each blood group was found to have similar susceptibility of acquiring malaria infection (χ(2 ) = 3.603; P = 0.3076) and P. falciparum infection (χ(2 ) = 1.818; P = 0.6110). The SPR was highest among children more than 2 years of age group and variation in SPR among the age groups was statistically significant (χ(2 ) = 17.186; P = 0.0018). No gender biasing was observed in malaria distribution. Anemia was found associated with the infection among both the sexes. The findings suggest that tea estates are endemic for stable malaria transmission primarily due to P. falciparum and the prevalence rate decline with age, suggesting the development of protective immunity. Promising intervention measures could be able to reduce the malaria prevalence effectively in the study areas.
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Affiliation(s)
- Bipul Rabha
- Defence Research Laboratory (DRL), P.B. No. 2, Tezpur, Assam India
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Imwong M, Nakeesathit S, Day NPJ, White NJ. A review of mixed malaria species infections in anopheline mosquitoes. Malar J 2011; 10:253. [PMID: 21880138 PMCID: PMC3201030 DOI: 10.1186/1475-2875-10-253] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 08/31/2011] [Indexed: 11/13/2022] Open
Abstract
Background In patients with malaria mixed species infections are common and under reported. In PCR studies conducted in Asia mixed infection rates often exceed 20%. In South-East Asia, approximately one third of patients treated for falciparum malaria experience a subsequent Plasmodium vivax infection with a time interval suggesting relapse. It is uncertain whether the two infections are acquired simultaneously or separately. To determine whether mixed species infections in humans are derived from mainly from simultaneous or separate mosquito inoculations the literature on malaria species infection in wild captured anopheline mosquitoes was reviewed. Methods The biomedical literature was searched for studies of malaria infection and species identification in trapped wild mosquitoes and artificially infected mosquitoes. The study location and year, collection methods, mosquito species, number of specimens, parasite stage examined (oocysts or sporozoites), and the methods of parasite detection and speciation were tabulated. The entomological results in South East Asia were compared with mixed infection rates documented in patients in clinical studies. Results In total 63 studies were identified. Individual anopheline mosquitoes were examined for different malaria species in 28 of these. There were 14 studies from Africa; four with species evaluations in individual captured mosquitoes (SEICM). One study, from Ghana, identified a single mixed infection. No mixed infections were identified in Central and South America (seven studies, two SEICM). 42 studies were conducted in Asia and Oceania (11 from Thailand; 27 SEICM). The proportion of anophelines infected with Plasmodium falciparum parasites only was 0.51% (95% CI: 0.44 to 0.57%), for P. vivax only was 0.26% (95% CI: 0.21 to 0.30%), and for mixed P. falciparum and P. vivax infections was 0.036% (95% CI: 0.016 to 0.056%). The proportion of mixed infections in mosquitoes was significantly higher than expected by chance (P < 0.001), but was one fifth of that sufficient to explain the high rates of clinical mixed infections by simultaneous inoculation. Conclusions There are relatively few data on mixed infection rates in mosquitoes from Africa. Mixed species malaria infections may be acquired by simultaneous inoculation of sporozoites from multiply infected anopheline mosquitoes but this is relatively unusual. In South East Asia, where P. vivax infection follows P. falciparum malaria in one third of cases, the available entomological information suggests that the majority of these mixed species malaria infections are acquired from separate inoculations.
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Affiliation(s)
- Mallika Imwong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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