Risk Mapping and Situational Analysis of Cutaneous Leishmaniasis in an Endemic Area of Central Iran: A GIS-Based Survey

Six-Year Study on Cutaneous Leishmaniasis in Al-Muthanna, Iraq: Molecular Identification Using ITS1 Gene Sequencing

BACKGROUND

The current study aimed to determine the prevalence of cutaneous leishmaniasis (CL) in Al-Muthanna province (Iraq) and to characterize the Leishmania species that cause cutaneous lesions through conventional polymerase chain reaction techniques in some patients during the first 7 months of the year 2020.

MATERIALS AND METHODS

Medical information on patients with CL was obtained from archived records at the Al-Muthanna Health Office's Public Health Department (2015-2020). In the Al-Hussein Teaching Hospital laboratory, 95 CL samples were collected and examined microscopically for molecular characterization using Giemsa staining.

RESULTS

Between 2015 and 2020, 2,325 patients (1,184 men and 1,141 women) were enrolled. Although CL occurred across all age groups, those aged range of 5-14 years had the highest proportion of infections (53.0%). This study found that most infections occurred between December and February, peaking in January. Only 63 of 95 CL samples were positive for the Internal Transcribed Spacer 1 region. L. tropica was found in 39 samples (61.9%), whereas L. major was found in 24 samples (38.1%), in CL patients. Although dermal lesions develop in all body regions, a single lesion is the most common. The upper limbs (13 of 16 samples, 33.3%)were infected with L. tropica, whereas the lower limbs (9 of 14 samples, 37.5%) were infected with L. major. In contrast to L. major, most L. tropica lesions occur in urban areas.

CONCLUSION

Our study indicates that CL is endemic in the Al-Muthanna province and that two Leishmania spp. coexist in the province. Molecular diagnosis is a vital component in determining many clinical symptoms of the Leishmania parasite as well as implementing suitable therapeutic, epidemiological, and control strategies.

Predicting current and future high-risk areas for vectors and reservoirs of cutaneous leishmaniasis in Iran

Climate change will affect the distribution of species in the future. To determine the vulnerable areas relating to CL in Iran, we applied two models, MaxEnt and RF, for the projection of the future distribution of the main vectors and reservoirs of CL. The results of the models were compared in terms of performance, species distribution maps, and the gain, loss, and stable areas. The models provided a reasonable estimate of species distribution. The results showed that the Northern and Southern counties of Iran, which currently do not have a high incidence of CL may witness new foci in the future. The Western, and Southwestern regions of the Country, which currently have high habitat suitability for the presence of some vectors and reservoirs, will probably significantly decrease in the future. Furthermore, the most stable areas are for T. indica and M. hurrianae in the future. So that, this species may remain a major reservoir in areas that are present under current conditions. With more local studies in the field of identifying vulnerable areas to CL, it can be suggested that the national CL control guidelines should be revised to include a section as a climate change adaptation plan.

Distribution and Risk of Cutaneous Leishmaniasis in Khyber Pakhtunkhwa, Pakistan

Cutaneous leishmaniasis (CL) is a zoonotic infection caused by obligate intracellular protozoa of the genus Leishmania. This study aimed to investigate CL in Khyber Pakhtunkhwa, Pakistan and to estimate the risk of epidemics. Clinico-epidemiological data of 3188 CL patients were collected from health facilities in 2021. Risk factors were analyzed using the chi-square test. ArcGIS V.10.7.1 was applied for spatial analysis. The association between CL occurrence and climatic variables was examined by Bayesian geostatistical analysis. The clinical data revealed males or individuals younger than 20 years old were more affected. Most patients presented with a single lesion, and the face was the most attacked body part. CL was prevalent in the southern region in winter. A proportional symbol map, a choropleth map, and a digital elevation model map were built to show the distribution of CL. Focal transmission was predicted by inverse distance weighting interpolation. Cluster and outlier analysis identified clusters in Bannu, Dir Lower, and Mardan, and hotspot analysis suggested Bannu as a high-risk foci. Bayesian geostatistical analysis indicated that increasing precipitation and temperature as well as low altitudes were associated with CL infection. The study has provided important information for public health sectors to develop intervention strategies for future CL epidemics.

Cutaneous Leishmaniasis Based on Climate Regions in Iran (1998-2021): A Systematic Review and Meta-Analysis

Background

Climate change can facilitate the expansion of leishmaniasis and create the suitable habitat for vector and reservoir species. The objective of this study was to estimate the prevalence of cutaneous leishmaniasis (CL) at the climatic regions of Iran.

Materials and Methods

The literature search was conducted to identify all published studies reporting the prevalence or incidence of CL in humans in Iran. A total of 350 articles that reported leishmaniasis in Iran were retrieved, due to eligibility criteria, only 42 studies were selected to the final systematic review and meta-analysis procedure. Random effects meta-analysis was done with the estimate of heterogeneity being taken from an inverse-variance model. Subgroup analysis was conducted and it stratified the studies according to climatic regions. Between-study heterogeneity was assessed by using I ² and Cochran's Q method I ² value of heterogeneity. Meta regression was used to investigate factors potentially contributed the between-study heterogeneity.

Results

Individual studies showed that prevalence per 100,000 population estimated the range from 1.5 to 318.7 with the overall random pooled prevalence of 83.3 (95% confidence interval 74.5-92.1). Subgroup analysis by climatic regions showed that many studies were conducted in the desert areas and also, it has more prevalent than the other climatic regions.

Conclusions

Leishmaniasis was more prevalent in regions with dry and desert climates than the other climatic regions. One of the advantages of this work is that the majority of selected studies have been conducted on population-base. However, some of the studies have been designed poorly or have had a lack of internal validity.

Environmental determinants predicting population vulnerability to high yellow fever incidence

Yellow fever (YF) is an endemic mosquito-borne disease in Brazil, though many locations have not observed cases in recent decades. Some locations with low disease burden may resemble locations with higher disease burden through environmental and ecohydrological characteristics, which are known to impact YF burden, motivating increased or continued prevention measures such as vaccination, mosquito control or surveillance. This study aimed to use environmental characteristics to estimate vulnerability to observing high YF burden among all Brazilian municipalities. Vulnerability was defined in three categories based on yearly incidence between 2000 and 2017: minimal, low and high vulnerability. A cumulative logit model was fit to these categories using environmental and ecohydrological predictors, selecting those that provided the most accurate model fit. Per cent of days with precipitation, mean temperature, biome, population density, elevation, vegetation and nearby disease occurrence were included in best-fitting models. Model results were applied to estimate vulnerability nationwide. Municipalities with highest probability of observing high vulnerability was found in the North and Central-West (2000-2016) as well as the Southeast (2017) regions. Results of this study serve to identify specific locations to prioritize new or ongoing surveillance and prevention of YF based on underlying ecohydrological conditions.

Spatio-temporal visualisation of cutaneous leishmaniasis in an endemic, urban area in Iran

INTRODUCTION

Cutaneous Leishmaniasis (CL) is a significant public health concern worldwide. Iran is among the most CL-affected countries, being one of the six most endemic countries in the world. This study aimed to provide a spatio-temporal visualisation of CL cases in an endemic urban area in north-eastern Iran identifying high-risk and low-risk areas during the period 2016-2019.

METHODS

This ecological study was conducted in the city of Mashhad, north-eastern Iran. All cases (n=2425) were diagnosed based on clinical findings and parasitological tests. The patient data were aggregated at the census tract level (the highest resolution available). CL incidence rates were subjected to Empirical Bayesian smoothing across the census tracts followed by spatial autocorrelation analysis to identify clusters and outliers. Spatial scan statistic was used to explore the purely temporal, purely spatial and spatio-temporal trend of the disease. In all instances, the null hypothesis of no clusters was rejected at p ≤0.05.

RESULTS

The overall crude incidence rate decreased from 34.6 per 100,000 individuals in 2016 to 19.9 per 100,000 in 2019. Cluster analysis identified high-risk areas in south-western Mashhad and low-risk areas in the north-eastern areas. Purely time scan statistics identified March to July as the time period with highest risk for CL occurrence. One most likely purely high-risk spatial cluster and six secondary purely high-risk spatial clusters were identified. Further, two spatio-temporal high-risk clusters, one in the north of the city from April to August and a second in the south-western part from March to September were observed.

CONCLUSIONS

Significant spatial, temporal and spatio-temporal patterns of CL distribution were observed in the study area, which should be considered when designing tailored interventions, such as effective resource allocation models, informed control plans and implementation of efficient surveillance systems. Furthermore, this study generated new hypotheses to test potential relationships between socio-economic and environmental risk factors and incidence of CL in high-risk areas.

Application of BASNEF model in students training regarding cutaneous leishmaniasis prevention behaviors: a school-based quasi experimental study

BACKGROUND

Cutaneous leishmaniasis (CL) is endemic in 98 countries, and 350 million people are at risk of the disease worldwide. In endemic areas, conducting educational interventions is necessary to change preventive behaviors of CL. This study aimed to investigate the effect of an educational intervention based on the BASNEF model on CL preventive behavior in students.

METHODS

The present quasi-experimental study examined 80 students living in endemic areas of leishmaniasis in Isfahan province, Iran based on the BASNEF model. The required data were collected twice before and two months after the educational intervention based on a questionnaire whose validity and reliability had been already proven in other studies. The intervention was performed in three educational sessions for the students in the intervention group and 1 educational session for teachers and parents. Data were analyzed by SPSS (VER26) using the chi-square test, independent t-test, analysis of covariance (ANCOVA), and Paired t-test.

RESULTS

After intervention, the mean scores of Knowledge (P < 0.001), attitude (P = 0.02), subjective norms (P = 0.04), behavioral intention (P < 0.001), and behavior (P = 0.02) indicated significant differences between the intervention and control groups, but an increase in mean scores of enabling factors was not significant (P = 0. 93).

CONCLUSIONS

Providing students with the educational intervention based on the BASNEF model improve their ability to the extent that they transmit these educations to their family members, which would be effective in preventing and controlling CL in leishmaniasis-prone areas.

TRIAL REGISTRATION

Name: Iranian Registry of Clinical Trials. Registration number: IRCT20201024049131N1. Registration date: 2020-11-20. Registration timing: prospective.

GIS-based risk mapping of cutaneous leishmaniasis: a survey in an endemic area of Central Iran

Cutaneous leishmaniasis (CL) is a vector-borne infectious disease that is affected by various environmental agents. The main objective of this study was to determine the spatial distribution of CL incidence by using Geographical Information System (GIS). This is a cross-sectional study that was conducted during 5 years from 2014 to 2018 in Isfahan, Iran. We used the required data on each leishmaniasis patient that were recorded from 44 counties of Isfahan in the databases and archive of the Provincial Health Centre. We used GIS for determining the incidence of CL in the high-risk foci. Moran index was used to identify high risk points (clustering in similar values) compared to the values of neighborhood points. Hot spot analysis was conducted by Getis-Ord-Gi. The highest incidence of the disease occurred in the age group of 18-64 years and 61.6% of patients were male. According to seasonal distribution, autumn (58.6%) had the highest frequency. Time trend of incidence showed that it had both decreasing and increasing, and there was a sudden upward trend of disease in 2018 except only two counties. The hot spots were involved the central areas of the Isfahan province slightly toward to the north and southeast of the province. Moran index showed that the differences for all points were not significant (p-value>0.05). Varzaneh (placed in southeast of Isfahan) was the hottest spot and had the worst position for leishmaniasis compared to all years and all cities.

The Geographical Distribution of Human Cutaneous and Visceral Leishmania Species Identified by Molecular Methods in Iran: A Systematic Review With Meta-Analysis

Leishmaniasis is one of the most common vector-borne parasitic diseases in Iran. Leishmania species identification is necessary for epidemiological aspects, precise prognosis, control and treatment of the disease. We systematically searched all the studies, reports, and documentation related to species identification and geographical distribution of causative agents of cutaneous (CL), mucosal (ML), and visceral leishmaniasis (VL) using DNA-based molecular diagnostic techniques in Iran. International databases including PubMed, ScienceDirect, Embase, Google Scholar, Scopus, and Web of Science were systemically searched for English articles and Iran's databases including SID, IranMedex and Magiran were searched for Persian reports and articles. Searches were performed from 1999 to 2019 (20 years). The current review was conducted using the keywords: cutaneous leishmaniasis, visceral leishmaniasis, Leishmania species, Human, Molecular, PCR, and Iran. The study quality was evaluated using the NOS checklist. This meta-analysis procedure was accomplished using STATA, version 2.7.9. Of the 3,426 records identified in the initial search, 154 articles met inclusion criteria and qualified for the systematic review and meta-analysis. In subgroup analysis, the pooled frequency of causative agents of CL isolates was 67.3% (95% CI: 59.51–74.67%) for L. major and 32.1% (95% CI: 24.72–39.87%) for L. tropica. In addition, the pooled frequency of causative agents of VL isolates was 97.1% (95% CI: 94.6–98.8%) for L. infantum and 2.9% (95% CI: 1.12–5.37%) for L. tropica. The findings of this study showed that the main causative agents of CL and VL in Iran are L. major and L. infantum, respectively. Moreover, kinetoplast DNA (kDNA) and internal transcriber spacer (ITS) were the most used markers for identifying Leishmania species. The current study provides valuable data to encourage and direct researchers as well as public health managers in the comprehensive leishmaniasis control and prevention planning in Iran.

Spatiotemporal patterns of cutaneous leishmaniasis in the district upper and lower Dir, Khyber Pakhtunkhwa, Pakistan: A GIS-based spatial approaches

While Cutaneous leishmaniasis (CL) is not a life-threatening disease, it leads to devastating effects on local community. CL is widely scattered manifesting a noticeable epidemiological pattern around the globe. The present study was planned to address the role of Geographic Information System (GIS) using CL clinico-epidemiological data to determine the high-risk areas of CL. Recorded data (2014-2018) of 3630 positive individuals was collected from Basic Health Units of the Upper and Lower Dir Districts, Khyber Pakhtunkhwa, Pakistan. Descriptive and statistical analysis was used for clinico-epidemiological characterization. For spatial analysis, ArcGIS V.10.3 was used and the CL average incidence was tagged on the proportional, choropleth, and digital elevation model maps. For focal transmission and high-risk zones, Inverse Density Weight (IDW) spatial interpolation, focal statistics, hot spot, cluster and outlier, and Bayesian geostatistical analysis were used. The trend of CL cases was elevated from 2014 to 2016 except for 2017 and 2018. Individuals of both genders younger than 20 years old were highly susceptible. Single lesions were more prominent (56%) and frequently affected facial parts (51%). The size and pretreatment duration of the CL lesion was significantly associated. Spatially, a choropleth map displayed the maximum CL incidences in Tehsil Balambat, Khal, and Termergara (31%-13%) located within a range of 948-1947m elevation in the central regions with proximal CL transmissions. Hot spot and cluster and outlier analysis affirmed that Tehsil Khal was the high-risk CL foci. The Bayesian geostatistical analysis revealed high temperature, less altitude, and annual precipitation as important risk factors. An increasing trend in CL transmission has become evident, affecting both genders and <20 years old children. GIS resolute the concealed CL hubs in the least elevated central regions which warrant the control strategies to restrict future epidemics.

New insights about human tick infestation features: a systematic review and meta-analysis

There are many studies that provide information regarding ticks infesting humans. However, there is no a meta-analysis about the global ranks of tick infestation rates and records, global monthly tick bites and annually and periodically trends of tick infestation rates, and the global tick infestation rates among years, mounts, regions, and countries. The study provides new insights about the above objectives in a global context and therefore performed. After a preliminary review of the 610 papers representing objective areas, 241 were selected for detailed meta-analysis. In general, the global ranks of tick species were, respectively, between 0.01-85.4% and 1-53 for human infestation rates and records. Twenty-six and sixteen tick species have more than 10% and 10 records of human tick infestation rates and records, respectively. It seems these tick species tend to be more blood-feeding on humans and as a result can be more dangerous to humans. The outcome of study demonstrated that there is no difference between seasonal human tick infestation patterns in the northern and southern hemispheres. The most global monthly mean tick bites in humans were observed in June then followed in July, August, May, and September. The global annually and periodically trends of tick infestation rates in humans exhibited decreasing trends over the past decades suggesting the preventive measure to prohibit human tick infestation have been successful. It seems that the ranks of tick infestation rates and records in humans may be as two indexes to illustrate the degree of importance of tick infesting humans.

Epidemiological and genetic characteristics of asymptomatic canine leishmaniasis and implications for human Leishmania infections in Egypt

Leishmaniasis is a neglected zoonotic disease that poses significant veterinary and public health risks in developing countries. Dogs act as a reservoir host for leishmaniasis transmitted to humans. A total of 108 human cases of cutaneous leishmaniasis (CL) were identified in the Al-Houd Al-Marsoud Hospital in Cairo, Egypt, during 2018. Blood samples and skin biopsies were collected for further examination. Blood samples from 96 asymptomatic dogs were collected. All samples were subjected to molecular and phylogenetic analysis. Quantitative RT-PCR was used to measure the expression of genes related to mTOR signalling and inflammation in blood and tissue samples. The distribution pattern of human cases pointed to an endemic focus in North Sinai (66.67%). The prevalence of asymptomatic canine leishmaniasis was 66.60%. Histopathological examination of human skin lesions revealed a severe granulomatous inflammatory reaction, necrosis and ulceration. Moreover, leishmanial amastigotes could be detected in human tissue samples. Phylogenetic analysis revealed 100% identity of human isolates to Leishmania tropica (MN453682), and dog isolates to Leishmania infantum (MN453673), with 94.9% similarity between the two isolates. Gene expression related to mTOR signalling and inflammation in both species' samples confirmed a significant alteration of EIF4EBP1, CCR4 and INF-γ expression compared with control groups. In Egypt, increased incidence of asymptomatic carrier dogs acting as a significant reservoir host for Leishmania poses a public health hazard. Findings warrant further epidemiological investigation of CL in Egypt, as well as additional study of parasite differentiation and gene regulation.

Cutaneous leishmaniasis in Iran: A systematic review and meta-analysis

Cutaneous leishmaniasis as a public health concern that attracts many attentions in endemic area. There is no exact estimation of cutaneous leishmaniasis in Iran. This study aimed to assess the exact prevalence of disease and carried out in databases including: Pub Med, Google Scholar, Science Direct, Scopus, Web of Science, Magiran, Iran doc, Barakatkns and Scientific Information Database (SID) from 2000 to 2019. Totally 84 studies were eligible to be included in this systematic review and Meta-analysis study. Based on a random effect model the pooled prevalence of leishmaniasis was estimated 45% (95% CI: 39%-51%; I^2 = 99.8%P < 0.001). The highest prevalence of CL was related to Isfahan 66% (53%-78%), Golestan 64% (62%-65%) and Fars province 63% (38%-84%) and the lowest prevalence was estimated in Kermanshah province 4% (4%-5%), Hormozgan 10% (8%-11%), Bushehr 12% (1%-35%) and Kerman 15% (9%-22%) provinces respectively. The lowest prevalence was associated with L. trapica spices 23% (11%-38%) and the highest was associated with L. major spices 32% (21%-45%). The prevalence with both L. trapica and L. major spices was achieved 60% (48%-71%). It is essential for health authorities to take steps to control and prevent the epidemic by rapid treatment of patients, destroying gerbils and promotion of general and health education for the local population.

Cutaneous Leishmaniasis during Pregnancy, Preterm Birth, and Neonatal Death: A Case Report

Cutaneous leishmaniasis (CL) is an emergent public health concern, particularly in tropical and subtropical regions. Reports of pregnancy complications are scarce; however, as the endemic range of CL expands in Iran, there is concern of possible detrimental effects on fetal development amongst infected mothers through placental transmission of the parasite or enhanced maternal immune responses. We herein describe the first known case of persistent anthroponotic CL, plausibly responsible for pregnancy complications, preterm birth, and neonatal death in a healthy Iranian primigravida woman. Diagnosis was based on physical examinations of the lesions on the back of both calves of the patient and laboratory analyses including direct smear, culture, and PCR. During active CL infection, the patient gave birth to a premature female neonate who passed three days post-delivery due to immature lung development and subsequent respiratory distress syndrome. This report highlights the challenges associated with CL infection during pregnancy, exacerbation of lesions, and subsequent complications.

Using geo-spatial analysis for assessing the risk of hospital admissions due to community-acquired pneumonia in under-5 children and its association with socially vulnerable areas (Brazil)

Background

The concentration of under-5 child morbidity and mortality due to pneumonia in developing countries reflects the social inequities. This study aimed to map and assess the spatial risk for hospitalization due to Community-Acquired Pneumonia in children under 5 years of age and its association with vulnerable areas.

Methods

Ecological study in the city of Ribeirão Preto, state of São Paulo, Brazil. The study population consisted of hospitalized under-5 children, diagnosed with community-acquired pneumonia, in Ribeirão Preto-São Paulo-Brazil, from 2012 to 2013. Data were collected in different databases, by a trained team, between March 2012 and August 2013 and from the 2010 Demographic Census of the Brazilian Institute of Geography and Statistics. The 956 urban census tracts were considered as the units of analysis. The incidence of cases per 10,000 inhabitants was calculated by census tracts during the study period. For the identification of the spatial risk clusters, the Kernel density estimator and the Getis-Ord Gi* technique were performed. Generalized additive models were used to verify the association between areas with social vulnerability and the occurrence of childhood pneumonia.

Results

The study included 265 children under the age of five, hospitalized due to community-acquired pneumonia. A concentration of cases was identified in the regions with greater social vulnerability (low income, poor housing conditions and homelessness), as well as a lower occurrence of cases in the most developed and economically privileged area of the city. The majority of the children lived in territories served by traditional primary healthcare units, in which the health surveillance and family and community focus are limited. It is important to highlight that the tracts with the highest degrees of vulnerability, such as those identified as high vulnerability (urban) and very high vulnerability (subnormal urban clusters).

Conclusions

The results contribute to the comprehension of the social factors involved in child hospitalization due to pneumonia, based on the analysis of the spatial distribution. This approach revealed a strategic tool for diagnosing the disparities as well presenting evidences for the planning in health and strength health care system in achieving equity, welfare and social protection of children.

Supplementary Information

Supplementary information accompanies this paper at 10.1186/s12887-020-02398-x.

Economic Burden Associated with Head Louse (Pediculus humanus capitis) Infestation in Iran

Background

The head louse infestation is a public health issue in the world especially, affecting most people who live in camps, school-aged children and their families. Head lice treatment has economic ramifications that often under calculated. The aim of this study was evaluation of economic burden associated with head louse infestation in Iran.

Methods

In a cross-sectional study, 500,002 infestations were diagnosed among suspected head lice infested people who referred to health care system in all provinces of Iran during 2017. Direct and indirect costs related to paid by patients and government systems were extracted by referring to accounting documents and interviews with patients and experts and were recorded in researcher-made forms. Microsoft Excel 2010 software was used for economic burden calculation.

Results

The incidence rate of head lice infestation in Iran was 500,002/79,926,270 (625.5 per 100,000 populations). Economic burden of head lice in the country was calculated at 5,790,143$. Direct and indirect costs, governmental cost, out of pocket and total costs of head lice were included 3.14$, 2.84$, 5.98$, 5.60$ and 11.58$ per case respectively.

Conclusion

The direct and indirect costs associated with treatment of infestations were relatively high. Therefore, the creation of medical facilities such as availability of diagnostic and treatment strategies can be effective in the control of infestation. The adoption of infestation prevention methods, such as health education to people at risk of infestation, reduces the incidence of head lice and imposition of related treatment costs on governmental health care system and head lice cases.

Spatiotemporal Variability of Zoonotic Cutaneous Leishmaniasis Based on Sociodemographic Heterogeneity. The Case of Northeastern Iran, 2011-2016

Zoonotic cutaneous leishmaniasis (ZCL) is one of the most prevalent zoonoses in Iran, especially in central and northeastern Iran. This research aimed to examine whether there were spatiotemporal clusters of ZCL cases, and if so, whether there were differences in clustering according to age, sex, area of residence, and occupation. Spatial analysis, including global and local spatial autocorrelations, inverse distance weighting, and space-time scan statistics, were used to determine potential clusters in the villages of Golestan from 2011-2016. Several spatially significant (p < 0.05) clusters were observed in the north and northeastern regions, and most persisted until the last year of the study period. Children (0-10 years) living in rural settings were more likely to have an infection than those living in other areas. Although the disease was centered in the northern regions, housekeepers, females, and patients aged 21-30 and 41-50 years were found to be the high-risk groups in the southern areas. The seasonal pattern indicated that the outbreak mainly began in late summer, peaked in October, and diminished in December. By exploring spatiotemporal variations of ZCL by sociodemographic information, this study was able to identify priority areas for decision-makers in healthcare and resource allocation.

Comparing spatio-temporal distribution of the most common human parasitic infections in Iran over two periods 2007 to 2012 and 2013 to 2018: A systematic quantitative literature review

This study analyses the spatio-temporal trend of the prevalence of the four most prevalent parasitic diseases in Iran over two periods, 2007 to 2012 and 2013 to 2018, indicating high-risk and low-risk areas. Out of 19 126 articles, we selected 220 articles for data extraction and calculated the pooled prevalence for cutaneous leishmaniasis, human toxoplasmosis, giardiasis and blastocystosis for all 31 provinces in the country. Anselin local Moran's I was used to identify clusters and outliers in the prevalence rates. The mean prevalence of cutaneous leishmaniasis patients was found 35.12 per 100 000 in 2007 to 2012 but fell to 19.12 per 100 000 in the 2013 to 2018 period. The mean prevalence of acute and chronic toxoplasmosis was 2.36% and 32.5%, respectively, in 2007 to 2012, which changed to 2.28% and 31.14% in 2013 to 2018. The total prevalence of giardiasis declined from 9.8% in 2007 to 2012 to 4.8% in 2013 to 2018, while the mean prevalence of blastocystosis declined from 8.9% in 2007 to 2012 to 6.76% in the 2013 to 2018 period. There was only one high-high cluster in 2007 to 2012 and that was due to giardiasis, while there were two in 2013 to 2018, one for blastocystosis and one for chronic toxoplasmosis. The total prevalence of blastocystosis, giardiasis and cutaneous leishmaniasis in Iran has continually declined since 2007. In contrast, the prevalence of toxoplasmosis in pregnant Iranian women has not been changed. Iran's Midwest has more parasitic infections compared to the Mideast, which may be explained by the existence of vast deserts and consequently dry and hot climate in the latter part of the country.

Forecasting head lice (Pediculidae: Pediculus humanus capitis) infestation incidence hotspots based on spatial correlation analysis in Northwest Iran

Background and Aim

Pediculus humanus capitis has been prevalent throughout the world, especially in developing countries among elementary students and societies with a weak socio-economic status. This study aimed to forecast head lice (Pediculidae: P. capitis) infestation incidence hotspots based on spatial correlation analysis in Ardabil Province, Northwest Iran.

Materials and Methods

In this retrospective analytical study, all cases of head lice infestations who were confirmed by Centers for Disease Control office have been studied from 2016 to 2018. Head lice infestation incidence hotspots in the province should be detected based on general G statistics in ArcMap GIS10.4.1. Furthermore, MaxEnt.3.3.3 model was used for modeling the high-risk areas.

Results

The prevalence rate of pediculosis was 14.90/100,000 populations. The general G statistics revealed that the head lice infestation in this study area has a high cluster pattern. The analysis showed that the Parsabad and Germi counties were identified as a head lice infestation incidence hotspots. Statistical and spatial analyses of head lice infestation incidence showed a significant positive correlation with head lice infestation incidence hotspots and the altitudes (15-500 m), annual temperature range (14-16.5°C), and slope and average diurnal temperature (12-18°C).

Conclusion

The results of this study showed that the most ecologically suitable areas of head lice occurrence were identified in two hotspots (Parsabad and Germi) in the Northern areas of Ardabil Province (Parsabad and Germi counties); in the borderline of Iran and the Republic of Azerbaijan.

New aspects about Crimean-Congo hemorrhagic fever (CCHF) cases and associated fatality trends: A global systematic review and meta-analysis

Crimean-Congo hemorrhagic fever (CCHF) is the most popular tick-borne disease causing by Crimean-Congo hemorrhagic fever virus (CCHFV). There are several valuable reviews considering some fields of the CCHF aspects. While there is no a systematic review about means and trends of CCHF cases and fatality rate, means and trends of CCHF cases and fatality rates of human occupations involved in CCHF. Therefore, this meta-analysis review performed to highlight and provide a global detailed of the above CCHF aspects. Among 398 collected papers, 173 papers were become this meta-analysis review. The study results confirm that an apparent increasing CCHF cases occurred through the past decades. The trends of annually and periodically CCHF cases and fatality rates were also increased. The means of annually and periodically CCHF cases and fatality rates were 57 and 432 cases, and 10 cases and 32.2 % and 49 cases and 28.8 %, respectively. The means of annually and periodically CCHF fatality rates are about one-tenth of CCHF human cases. The mean of CCHF fatality rates in Africa (22.0 %) is lower than Asia (33.5 %) and Europe (33.8 %). Among occupations involved in CCHF, agricultural (28.9 %), health-care (19.2 %) and slaughterhouse (16.7 %) workers, and farmers (13.9 %) had the maximum CCHF fatality rates in order. Based on literature review of CCHFV S-segment aspects, several clades and genotypes are reported to distribute in Africa, Asia and Europe regions. There are very wide fields to investigate the epidemiology characteristics of CCHFV clades, genotypes and their distribution in the future.

Leprosy in urban space, areas of risk for disability and worsening of this health condition in Foz Do Iguaçu, the border region between Brazil, Paraguay and Argentina

BACKGROUND

Leprosy is a public health problem and a challenge for endemic countries, especially in their border regions where there are intense migration flows. The study aimed to analyse the dynamics of leprosy, in order to identify areas of risk for the occurrence of the disease and disability and places where this health condition is worsening.

METHOD

This ecological study considered the new cases of leprosy reported in the municipality of Foz do Iguaçu from 2003 to 2015. Spatial and spatial-temporal scan statistics were used to identify the risk areas for the occurrence of leprosy, as well as the Getis-Ord Gi and Getis-Ord Gi* methods. Areas of risk for disabilities were identified by the scan statistic and kernel density estimation.

RESULTS

A total of 840 cases were reported, of which 179 (21.3%) presented Grade 1 or 2 disabilities at the time of diagnosis. Leprosy risk areas were concentrated in the Southern, Eastern and Northeastern Health Districts of the municipality. The cases of Grade 2 disability were observed with higher intensity in regions characterized by high population density and poverty.

CONCLUSION

The results of the study have revealed changes in the pattern of areas at risk of leprosy according to the investigated periods. In addition, it was possible to verify disabilities as a condition present in the investigated cases, or that may be related to the late diagnosis of the disease. In the areas of risk identified, patients have reported worse physical disability after diagnostic confirmation, or indicate inadequate clinical examination, reinforcing the need for structuring leprosy control services in a qualified manner.

Modelling and evaluating the risk of zoonotic cutaneous leishmaniasis in selected areas of Kerman Province, south of Iran

Cutaneous leishmaniasis (CL) remains a public health problem in the world, particularly in tropical and sub-tropical countries. This study aimed to determine the hotspots of CL in Kerman Province of Iran and model their potential for the establishment of new disease foci. All documents related to studies conducted in Kerman Province on CL published between 1978 and 2017 were retrieved and categorized. Spatial distributions of the vector, reservoir and human infection of CL were mapped. MaxEnt ecological model was used to predict the environmental suitability of the vector and reservoir(s) of zoonotic cutaneous leishmaniasis (ZCL). The most hazardous sites with the potential for the establishment of new disease foci were determined for field operations. Statistics of new cases of CL was obtained from the Center for Disease Control (CDC) of the ministry of health for the period 2011-2016. A total of 6,056 cases of CL were recorded, while we found a decreasing pattern in the incidence of CL from 46.48 per 100,000 inhabitants to 22.97. The best ecological niches for Phlebotomus papatasi are located in the central, western, northwest and southwest regions of the province. Also, environmental suitability for the reservoirs was highest in the central, southern and southwestern regions. The model predicted the gerbils can be present in some foci of anthroponotic cutaneous leishmaniasis (ACL). However, this result should be confirmed through a precise field study, and if validated, plans should be made to prevent the emergence of new foci of ZCL in the risk areas.

The Temporal and Spatial Evolution of Marathons in China from 2010 to 2018

The purpose of this study is to explore the spatial distribution pattern and influencing factors of the Chinese marathon. Geographic Information System (GIS) related spatial analysis tools were used to calculate the following-averaged nearest neighbor index, nuclear density analysis and hot spot analysis among others. The spatial distribution evolution characteristics and the influencing factors of eighteen Chinese marathon events in 2010, 129 in 2015 and 342 in 2018 were analyzed. The results show that (a) in 2010 the nearest neighbor ratio was 1.164714, Moran's I was -0.010165 (type: Random), in 2015 it was 0.502146, Moran's I was 0.066267 (type: Clustered) and in 2018 it was 0.531149 and Moran's I was 0.083485 (type: Clustered); (b) in 2010 there was a 333.6 km search radius; the core circle of the Yangtze River Delta was adopted. In 2015 and 2018, a search radius of 556 km was adopted, which was respectively obtained from the core circle of the Yangtze River Delta, the core circle of Beijing-Tianjin-Hebei and the core circle of East China; (c) according to the Z-value data, East China and North China in 2015 passed 95% confidence in five provinces and municipal hot spots, passed 90% confidence in three hot spots and passed 95% confidence in Chongqing Cold Point. In 2018, East China, North China, Central Region and eight other provinces and cities' hot spots passed 95% confidence, four hot spots passed 90% confidence, the Tibet Autonomous Region cold spot passed 90% confidence. Conclusion: The overall distribution of marathon events is greater in the eastern region than the western region, greater in the southern region than the northern region and greater in coastal regions than the inland regions; the nuclear density distribution has spread from the Yangtze River Delta mononuclear circle in 2010 to the core circle of the entire East China region. Moreover, it spread to North China, Central China and South China; the distribution of hot spots spread from Shanghai, Jiangsu and Zhejiang to the entire North China and East China regions. During the past thirty-eight years of development of the Chinese marathon, it has been divided into three stages due to different political, economic and social environments.

Epidemiological Study of Cutaneous Leishmaniasis in Neyshabur County, East of Iran (2011-2017)

BACKGROUND:

Cutaneous Leishmaniasis (CL) isn’t a lethal disease, but it has always been taken into consideration due to more involvement of patients with skin ulcers and its long-term treatment. Various factors can play an intervening role in increasing the rate of disease. The present study aimed to evaluate the prevalence and associated factors of disease from 2011-2017 and provide appropriate control strategies for reducing its incidence in Neyshabur county.

METHODS:

All patients with CL, who had medical records in the health centres of Neyshabur from 2011 to 2017, were examined for conducting this cross-sectional analytical study. Data were analyzed by descriptive statistics and chi-square test at a 0.05 using Statistical Package for the Social Sciences (SPSS V.22).

RESULTS:

Findings indicated that the highest annual incidence was in 2016 (229 patients), and the least incidence was in 2014 (100 patients). The majority of patients were under 10 years of age and 51.7% of patients were male. About 59.5% of patients were living in cities and 35% of them were living in North of Neyshabur city. Hands were the most affected part of the body (56.0%) followed by trunk (1.3%). Most patients (69.9%) were treated with topical regimens.

CONCLUSION:

This study showed that CL was hypo-endemic in Neyshabur. Also, the disease was more prevalent in urban areas. Therefore, appropriate health measures to improve environmental conditions, public health educations, and the public awareness of the positive impact of early diagnosis of disease in the success of treatment (especially for inhabitance suburbanite) are essential.

Spatial Distribution of Cutaneous Leishmaniasis Cases Referred to Health Centers of Three Khorasan Provinces in Iran Using Geographical Information System

BACKGROUND

Nowadays, geographic information system (GIS) is one of the most useful epidemiological tools for identifying high-risk areas of cutaneous leishmaniasis. The aim of this study was to determine the spatial distribution of cutaneous leishmaniasis in northeastern Iran.

METHODS

In this cross-sectional study, information on positive cases of cutaneous leishmaniasis in the three provinces located in northeastern Iran during Jul 2011 to Jul 2017 was obtained from the Iranian Ministry of Health. Based on the postal address of each case, the geographical coordinates of each patient were determined for spatial analysis of cutaneous leishmaniasis. For spatial analysis, Moran's index autocorrelation and Kriging interpolation method were used in GIS software.

RESULTS

Moran's index autocorrelation showed that spatial distribution of disease incidence in the study area was cluster pattern (Z-score > 1). In addition, Kriging interpolation method revealed that 90% of southern parts of North Khorasan province and northern parts of Razavi Khorasan Province formed hot spots.

CONCLUSION

The CL incidence is a function of spatial and geographical trends. In addition, spatial trends in the disease incidence distribution indicate that it is not greatly increased or decreased from one area to another. It appears as hot spots areas. Spatial analysis by showing high risk areas can be useful tools for controlling and preventing CL incidence.

Fish tank granuloma: An emerging skin disease in Iran mimicking Cutaneous Leishmaniasis

OBJECTIVE

Mycobacterium marinum causes a rare cutaneous disease known as fish tank granuloma (FTG). The disease manifestations resemble those associated with Cutaneous Leishmaniasis (CL). The aim of this study was to determine whether FTG was the cause of cutaneous lesions in patients who were referred to the Parasitology laboratory of Imam Reza Hospital in Mashhad to be investigated for CL.

MATERIALS/METHODS

One hundered patients, clinically diagnosed with CL between April 2014 and March 2015, were included in this study. Ziehl-Neelsen staining was performed to identify acid-fast Mycobacterium in addition to bacterial cultures using Löwenstein-Jensen medium. Skin lesion samples were also collected and kept on DNA banking cards for PCR testing.

RESULTS

Twenty-nine of the 100 individuals with skin lesions, and therefore suspected of suffering from CL, tested positive for Mycobacterium marinum by PCR. Of these, 21 (72.4%) were male and 8(27.6%) were female. In 97% of these cases the lesions were located on hands and fingers. These patients had a history of manipulating fish and had been in contact with aquarium water. A sporotrichoid appearance was observed in 58.6% of the patients with mycobacterial lesions; 67% of patients had multiple head appearance.

CONCLUSION

Patients suspected to have CL and who test negative for CL could be affected by FTG. Therefore, after obtaining an accurate case history, molecular diagnosis is recommended for cases that give a negative result by conventional methods.

Prone Regions of Zoonotic Cutaneous Leishmaniasis in Southwest of Iran: Combination of Hierarchical Decision Model (AHP) and GIS

BACKGROUND

Cutaneous leishmaniasis due to Leishmania major is an important public health problem in the world. Khuzestan Province is one of the main foci of zoonotic cutaneous leishmaniasis (ZCL) in the southwest of Iran. We aimed to predict the spatial distribution of the vector and reservoir(s) of ZCL using decision-making tool and to prepare risk map of the disease using integrative GIS, RS and AHP methods in endemic foci in Shush (plain area) and Khorramshahr (coastal area) counties of Khuzestan Province, southern Iran from Mar 2012 to Jan 2013.

METHODS

Thirteen criteria including temperature, relative humidity, rainfall, soil texture, soil organic matter, soil pH, soil moisture, altitude, land cover, land use, underground water depth, distance from river, slope and distance from human dwelling with the highest chance of the presence of the main vector and reservoir of the disease were chosen for this study. Weights of the criteria classes were determined using the Expert choice 11 software. The presence probability maps of the vector and reservoir of the disease were prepared with the combination of AHP method and Arc GIS 9.3.

RESULTS

Based on the maps derived from the AHP model, in Khorramshahr study area, the highest probability of ZCL is predicted in Gharb Karoon rural district. The presence probability of ZCL was high in Hossein Abad and Benmoala rural districts in the northeast of Shush.

CONCLUSION

Prediction maps of ZCL distribution pattern provide valuable information which can guide policy makers and health authorities to be precise in making appropriate decisions before occurrence of a possible disease outbreak.

Detection of risk clusters for deaths due to tuberculosis specifically in areas of southern Brazil where the disease was supposedly a non-problem

Background

Tuberculosis (TB) is the infectious disease that kills the most people worldwide. The use of geoepidemiological techniques to demonstrate the dynamics of the disease in vulnerable communities is essential for its control. Thus, this study aimed to identify risk clusters for TB deaths and their variation over time.

Methods

This ecological study considered cases of TB deaths in residents of Londrina, Brazil between 2008 and 2015. We used standard, isotonic scan statistics for the detection of spatial risk clusters. The Poisson discrete model was adopted with the high and low rates option used for 10, 30 and 50% of the population at risk, with circular format windows and 999 replications considered the maximum cluster size. Getis-Ord Gi* (Gi*) statistics were used to diagnose hotspot areas for TB mortality. Kernel density was used to identify whether the clusters changed over time.

Results

For the standard version, spatial risk clusters for 10, 30 and 50% of the exposed population were 4.9 (95% CI 2.6–9.4), 3.2 (95% CI: 2.1–5.7) and 3.2 (95% CI: 2.1–5.7), respectively. For the isotonic spatial statistics, the risk clusters for 10, 30 and 50% of the exposed population were 2.8 (95% CI: 1.5–5.1), 2.7 (95% CI: 1.6–4.4), 2.2 (95% CI: 1.4–3.9), respectively. All risk clusters were located in the eastern and northern regions of the municipality. Additionally, through Gi*, hotspot areas were identified in the eastern and western regions.

Conclusions

There were important risk areas for tuberculosis mortality in the eastern and northern regions of the municipality. Risk clusters for tuberculosis deaths were observed in areas where TB mortality was supposedly a non-problem. The isotonic and Gi* statistics were more sensitive for the detection of clusters in areas with a low number of cases; however, their applicability in public health is still restricted.

Modeling spatial risk of zoonotic cutaneous leishmaniasis in Central Iran

Zoonotic Cutaneous Leishmaniasis (ZCL) is one of the endemic diseases in central part of Iran. The aim of this cross-sectional study was to find the areas with a higher risk of infection considering the distribution of vector, reservoir hosts and human infection. Passive data recorded the positive cases of cutaneous leishmaniasis in Yazd province health center were collected for 10 years, from 2007 to 2016 at the County level. Considering all earlier studies conducted in Yazd province, records of Phlebotomus papatasi, the main vector of ZCL, and Rhombomys opimus, the main reservoir of ZCL, were collected and entered in a database. ArcGIS and MaxEnt model were used to map and predict the best ecological niches for both vector and reservoir. The most cumulative incidence of the disease was found to be in Khatam County, south of Yazd province. The area under curve (AUC) for R. opimus and P. papatasi was 0.955 and 0.914, respectively. We found higher presence probability of both vector and reservoir in central and eastern parts of the province. The jackknife test indicated that temperature and normalized difference vegetation index (NDVI) had the most effect on the model for the vector and reservoir, respectively. The areas with higher presence probability for the reservoirs and vectors were considered having the higher potential for ZCL transmission. These findings can be used to prevent and control the disease.

Use of mobile technology-based participatory mapping approaches to geolocate health facility attendees for disease surveillance in low resource settings

BACKGROUND

Identifying fine-scale spatial patterns of disease is essential for effective disease control and elimination programmes. In low resource areas without formal addresses, novel strategies are needed to locate residences of individuals attending health facilities in order to efficiently map disease patterns. We aimed to assess the use of Android tablet-based applications containing high resolution maps to geolocate individual residences, whilst comparing the functionality, usability and cost of three software packages designed to collect spatial information.

RESULTS

Using Open Data Kit GeoODK, we designed and piloted an electronic questionnaire for rolling cross sectional surveys of health facility attendees as part of a malaria elimination campaign in two predominantly rural sites in the Rizal, Palawan, the Philippines and Kulon Progo Regency, Yogyakarta, Indonesia. The majority of health workers were able to use the tablets effectively, including locating participant households on electronic maps. For all households sampled (n = 603), health facility workers were able to retrospectively find the participant household using the Global Positioning System (GPS) coordinates and data collected by tablet computers. Median distance between actual house locations and points collected on the tablet was 116 m (IQR 42-368) in Rizal and 493 m (IQR 258-886) in Kulon Progo Regency. Accuracy varied between health facilities and decreased in less populated areas with fewer prominent landmarks.

CONCLUSIONS

Results demonstrate the utility of this approach to develop real-time high-resolution maps of disease in resource-poor environments. This method provides an attractive approach for quickly obtaining spatial information on individuals presenting at health facilities in resource poor areas where formal addresses are unavailable and internet connectivity is limited. Further research is needed on how to integrate these with other health data management systems and implement in a wider operational context.

First case report of atypical disseminated cutaneous leishmaniasis in an opium abuser in Iran

Leishmaniasis is a worldwide tropical infectious disease caused by different species of intracellular protozoa parasites of the genus Leishmania . Herein, we report a 78-year-old man with unusual diffuse cutaneous leishmaniasis (DCL) who had a history of opium abuse and chronic obstructive pulmonary disease (COPD). He had multiple papular, crusted and severely ulcerated lesions extended to his arm and chest. Direct smears and skin punch biopsy of the lesions were suggestive of leishmaniasis. Parasite DNA was amplified from ulcers, and identified as Leishmania major by PCR-RFLP, confirmed by sequencing analyses. The aim of the current study was to bring to attention this atypical form of disease in CL endemic countries. Thus, this is the first case of DCL in an opium abuser with COPD due to L. major in Northeastern Iran indicating that atypical and extensive forms of CL (DCL) owing to L. major are increasing in Iran.

Molecular Identification and Phylogenetic Classification of Leishmania spp. Isolated from Human Cutaneous Leishmaniasis in Iran: A Cross-sectional Study

BACKGROUND

In Iran, both forms of cutaneous (CL) and visceral leishmaniasis (VL) have been reported; so the accurate species identification of the parasite(s) and the analysis of genetic diversity are necessary.

METHODS

The smears were collected from lesions samples of 654 patients with CL, who attended local health centers in 12 provinces of Iran during 2013-2015. The smears were checked for the presence of amastigotes by light microscopy. DNA of 648 Leishmania isolates, amplified by targeting a partial sequence of ITS (18S rRNA-ITS1-5.8S rRNA-ITS2) gene. Twenty-five of all the amplicons were sequenced and analyzed with restriction fragment length polymorphism (RFLP) using the Taq1 enzyme.

RESULTS

All the smears were positive microscopically. The PCR-RFLP analysis revealed that 176 (27%) CL patients were infected with L. tropica and, 478 (73%) with L. major. The dominant species in all over Iran is L. major. The sequencing results of all CL patients and RFLP analysis confirmed each other. Based on our phylogenetic tree, 25 ITS DNA sequences were grouped into two clusters representing L. major and L. tropica species. Phylogenetic tree derived from the ITS sequences supports a clear divergence between L. major from the other species.

CONCLUSION

Discrimination of Iranian Leishmania isolates using ITS gene gives us this opportunity to detect, identify, and construct the phylogenetic relationship of Iranian isolates.

Situational Analysis of Visceral Leishmaniasis in the Most Important Endemic Area of the Disease in Iran

BACKGROUND

Visceral leishmaniasis is one of the most important vector borne diseases in the world, transmitted by sand flies. Despite efforts to prevent the spread of the disease, cases continue worldwide. In Iran, the disease usually occurs in children under 10 years. In the absence of timely diagnosis and treatment, the mortality rate is 95-100%. The main objective of this study was to determine the spatial and temporal distribution of visceral leishmaniasis as well as its correlation with climatic factors for determining high-risk areas in an endemic focus in northwestern Iran.

METHODS

In this cross-sectional study, data on VL cases were collected from local health centers in Ardabil Province, Iran during 2001-2015 to establish a geodatabase using ArcGIS10.3. Data analysis was conducted using SPSS23 and ArcMap Spatial Analyst. MaxEnt model was used to determine ecologically suitable nichesfor the disease.

RESULTS

Two hotspots were found in Meshkinshahr and Germi counties with 59% and 23% of total cases, respectively. There was an increase in the incidence rate of VL in Ardabil County from 2.9 in 2009 to 9.2/100,000 population in 2015. There was no spatial autocorrelation between county and total number of cases (P> 0.05). Higher NDVI, lower altitude and southern aspects had positive effects on the presence probability of VL.

CONCLUSION

The number of cases of this disease have been rising since 2013 and doubled in 2015. According to the derived distribution maps, the disease is spreading to new locations such as Ardabil and Namin counties.

Distribution and Seasonal Activity of Phlebotominae Sand Flies in Yazd and Its Outskirts, Center of Iran

Background

Phlebotominae sand flies are the main vectors of leishmaniasis and some other diseases.

Materials and Methods

Using sticky traps, sand flies were collected fortnightly from outdoors and indoors areas of selected sites.

Results

A total of 2032 specimens (498 in the city and 1534 in the outskirts of Yazd) belonging to 11 species were collected. The activity of sand flies started in early-April and ended in mid-November. There were two peaks of activity in the end of April and mid-September. Phlebotomus sergenti and P. papatasi were the most abundant species in the city and outskirts of Yazd city, respectively. Other species were P. salehi, P. ansarii, P. kazerouni, P. caucasicus, P. andrejevi, P. alexandri, P. mongolensis, Sergentomyia sintoni, and S. palestinensis.

Conclusion

In comparison to some other parts of Iran, the extended period between two peaks suggests that the larvae to adult development of sand fly were delayed by the higher temperature of the summer months in Yazd province.

Arginase activity of Leishmania isolated from patients with cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) is one of the most important vector-borne parasitic diseases, highly endemic in Iran, and its prevalence is increasing all over the country. Arginase (ARG) activity in isolated Leishmania parasites from CL patients is yet to be explored. This study aimed to compare the ARG activity of isolated Leishmania promastigotes from CL patients with a standard strain of Leishmania major and its influences on the disease pathogenesis. We recruited 16 confirmed CL patients from Qom Province, in central Iran; after detection of Leishmania species using PCR-RFLP, we assessed the levels of ARG in the isolated promastigotes and determined the parasites' growth rate. Only L. major was identified from CL patients. The level of ARG activity in the isolated Leishmania promastigotes from CL patients was significantly higher than that obtained from the standard strain of L. major. No significant correlations between ARG activity and lesion size, number or duration were observed; in contrast, a significant negative correlation was seen between ARG level and Leishmania' growth rate. The obtained results suggest that increased ARG expression and activity in the isolated Leishmania promastigotes might contribute to the higher parasite infectivity and play a major role in the pathogenicity of the CL.

Arginase activity in pathogenic and non-pathogenic species of Leishmania parasites

Proliferation of Leishmania (L.) parasites depends on polyamine availability, which can be generated by the L-arginine catabolism and the enzymatic activity of arginase (ARG) of the parasites and of the mammalian hosts. In the present study, we characterized and compared the arginase (arg) genes from pathogenic L. major and L. tropica and from non-pathogenic L. tarentolae. We quantified the level of the ARG activity in promastigotes and macrophages infected with pathogenic L. major and L. tropica and non-pathogenic L. tarentolae amastigotes. The ARG's amino acid sequences of the pathogenic and non-pathogenic Leishmania demonstrated virtually 98.6% and 88% identities with the reference L. major Friedlin ARG. Higher ARG activity was observed in all pathogenic promastigotes as compared to non-pathogenic L. tarentolae. In vitro infection of human macrophage cell line (THP1) with pathogenic and non-pathogenic Leishmania spp. resulted in increased ARG activities in the infected macrophages. The ARG activities present in vivo were assessed in susceptible BALB/c and resistant C57BL/6 mice infected with L. major, L. tropica and L. tarentolae. We demonstrated that during the development of the infection, ARG is induced in both strains of mice infected with pathogenic Leishmania. However, in L. major infected BALB/c mice, the induction of ARG and parasite load increased simultaneously according to the time course of infection, whereas in C57BL/6 mice, the enzyme is upregulated solely during the period of footpad swelling. In L. tropica infected mice, the footpads' swellings were slow to develop and demonstrated minimal cutaneous pathology and ARG activity. In contrast, ARG activity was undetectable in mice inoculated with the non-pathogenic L. tarentolae. Our data suggest that infection by Leishmania parasites can increase ARG activity of the host and provides essential polyamines for parasite salvage and its replication. Moreover, the ARG of Leishmania is vital for parasite proliferation and required for infection in mice. ARG activity can be used as one of the main marker of the disease severity.

Potential Challenges of Controlling Leishmaniasis in Sri Lanka at a Disease Outbreak

The present works reviewed the existing information on leishmaniasis in Sri Lanka and in other countries, focusing on challenges of controlling leishmaniasis in the country, in an outbreak. Evidence from recent studies suggests that there is a possibility of a leishmaniasis outbreak in Sri Lanka in the near future. Difficulty of early diagnosis due to lack of awareness and unavailability or inadequacy of sensitive tests are two of the main challenges for effective case management. Furthermore, the absence of a proper drug for treatment and lack of knowledge about vector biology, distribution, taxonomy and bionomics, and reservoir hosts make the problem serious. The evident potential for visceralization in the cutaneous variant of L. donovani in Sri Lanka may also complicate the issue. Lack of knowledge among local communities also reduces the effectiveness of vector and reservoir host control programs. Immediate actions need to be taken in order to increase scientific knowledge about the disease and a higher effectiveness of the patient management and control programs must be achieved through increased awareness about the disease among general public and active participation of local community in control activities.