Fifty years of struggle to control cutaneous leishmaniasis in the highest endemic county in Iran: A longitudinal observation inferred with interrupted time series model

Global Dilemma and Needs Assessment Toward Achieving Sustainable Development Goals in Controlling Leishmaniasis

Leishmaniasis is a disease of poverty that imposes a devastating medical, social, and economic burden on over 1 billion people nationwide. To date, no in-depth study to analyze the major global challenges and needs assessment has been carried out. This investigation aimed to explore a comprehensive narrative review of leishmaniasis's main challenges and initially highlight obstacles that might impede the implementation of control measures. Also, we propose a specific list of priorities for needs assessment. The presence of socioeconomic factors, multiple clinical and epidemiological forms, various Leishmania species, the complexity of the life cycle, the absence of effective drugs and vaccines, and the lack of efficient vector and reservoir control make this organism unique and sophisticated in playing a tangled role to react tricky with its surrounding environments, despite extensive efforts and implementation of all-inclusive former control measures. These facts indicate that the previous strategic plans, financial support, and basic infrastructures connected to leishmaniasis surveillance are still insufficient. Strengthening the leishmaniasis framework in a context of accelerated programmatic action and intensification of cross-cutting activities along with other neglected tropical diseases (NTDs) is confidently expected to result in greater effectiveness, cost-benefit, and fruitful management. Sensitive diagnostics, effective therapeutics, and efficacious vaccines are vital to accelerating advancement toward elimination, and reducing morbidity/mortality and program costs. Collective actions devoted by all sectors and policy-makers can hopefully overcome technical and operational barriers to guarantee that effective and coordinated implementation plans are sustained to meet the road map for NTDs 2021- 2030 goals.

A prospective longitudinal study on the elimination trend of rural cutaneous leishmaniasis in southeastern Iran: Climate change, population displacement, and agricultural transition from 1991 to 2021

Leishmaniasis is a complex disease. Any change in weather conditions affects the humans' social and agricultural expansion and, consequently, the parasite's life cycle in terms of ecology, biodiversity, social stigma, and exclusion. This population-based prospective longitudinal investigation was conducted between 1991 and 2021 in a well-defined CL (cutaneous leishmaniasis) focus in Bam County, southeastern Iran. A robust health clinic and health surveillance system were responsible for the ongoing systematic documentation, detection, identification, and management of CL cases. The exponential smoothing method via the state space model was used in the univariate time series. The TTR, smooth, and forecast packages were used in R software. Landsat satellite images from 1991, 2001, 2011, and 2021 were employed in the physical development. During this period, the temperature increased while the rainfall and humidity decreased. The findings showed a downward trend in the standardized drought index. Also, the results showed that climate warming and ecological changes profoundly affected the area's agricultural patterns and topographical features. Furthermore, the last three decades witnessed an elimination trend for zoonotic CL (ZCL) and the predominance of anthroponotic CL (ACL). The present findings showed that the critical factors in the predominance of ACL and elimination of ZCL were rising temperature, drought, migration, unplanned urbanization, earthquake, and agrarian reform. The wall-enclosed palm tree gardens excluded the primary ZCL reservoir host. They controlled the disease while providing suitable conditions for the emergence/re-emergence of ACL in the newly established settlements and the unplanned ecozone. Therefore, robust health infrastructures, sustained financial support, and evidence-based research studies are crucial to facilitating the necessary surveillance, monitoring, and evaluation to control and eliminate the disease.

Geographical and climatic risk factors of cutaneous leishmaniasis in the hyper-endemic focus of Bam County in southeast Iran

Introduction

Cutaneous leishmaniasis (CL) is a prevalent debilitating disease in many countries, particularly in Iran, the Middle East, North Africa, and South America. Bam County is the most important highly endemic focus of anthropometric CL in Iran and has been under consideration by WHO. This study investigated the environmental and geographic factors affecting the occurrence and distribution of CL in this focus.

Methods

Demographic data and the home addresses of CL patients diagnosed from 2015 to 2020 were retrieved from the Leishmaniasis Center of Bam in southeast Iran. The effects of mean annual rainfall (MAR), mean annual humidity (MAH), mean annual temperature (MAT), maximum annual temperature (MaxMAT), minimum annual temperature (MinMAT), mean annual humidity (MAH), mean annual evaporation (MAE), mean annual frosty days (MAFD), mean annual snowy hours (MASH), elevation, and land cover on the distribution of CL were analyzed using geographical information systems (GIS) and univariate and multivariate regression models.

Results

Of 847 patients studied, 50.9% (n = 431) were female and 49.1% (n = 416) were male. The age classes 0-10 (n = 246) and 11-20 (n = 145) showed the highest frequency of patients, respectively. Leishmaniasis patients were reported from 66 villages/cities (11.8%) out of 561 residential areas in Bam County. Univariate analysis showed that urban settings (OR = 21.66), agriculture (OR = 5.73), orchards (OR = 5), salty land (OR = 1.05), and temperatures (OR = 2.37, 2.79 and 3.47) had positive effects on CL occurrence (p < 0.05), while altitude, precipitation, humidity, evaporation, and the number of frozen days had negative effects. Multivariate analysis identified urban settings (OR = 13.6), orchards (OR = 6.29), agriculture (OR = 5.82), and minimum temperature (OR = 2.38) as the most significant determinants of CL occurrence in this region.

Conclusion

Environmental and ecological factors play an important role in the distribution of CL in Bam County. The high-risk zones for CL are cities/large villages, agricultural and orchard areas in lower altitudes and with warmer climates and lower rainfall and humidity. This model can guide researchers and health managers to properly conduct CL control programs and allocate budgets.

Real-time impact of COVID-19 pandemic on cutaneous leishmaniasis case finding and strategic planning, preventive interventions, control and epidemiology in a region with a high burden of cutaneous leishmaniasis and COVID-19: A cross-sectional descriptive study based on registry data in Ilam-Iran

Background and Aims

Cutaneous leishmaniasis (CL) is a severe parasitic disease affecting people, mostly in underdeveloped nations. As a zoonotic infection yearly incidence of CL depends on several parameters such as demographic, epidemiological, and environmental factors as well as prevention and control measures. The sudden outbreak of pandemics such as SARS-Corona-Virus-2 pandemic, can probably affect the incidence or reporting of other diseases, especially infectious diseases, in various ways such as pressure on health systems, providing sanitary services and its components, lockdowns and changes in people's living habits.

Aim

This study aimed to evaluate the COVID-19 impact on the incidence and other epidemiological aspects as well as control measures of CL in Ilam Province-Iran.

Methods

Required data was extracted from the CL registration system in Ilam from 2014 to 2021 to demonstrate the trend of CL incidence before and after COVID-19 pandemic.

Results

Based on our results, a declining pattern of CL incidence was observed, accompanied by the advent and intensification of the viral pandemic in Iran and Ilam province. Although, this decreasing pattern was not integral in all areas, and even increase in CL detection was emphasized in some regions.

Conclusion

It may be inferred that the COVID-19 pandemic may disrupt treatment programs of CL cases, rodent nest destruction, and fighting vector insects.

Outbreak of cutaneous leishmaniasis before and during the COVID-19 pandemic in Jahrom, an endemic region in southwest of Iran

The emergence of the Coronavirus Disease 2019 (COVID-19) pandemic has a considerable effect on the burden of other diseases. Cutaneous leishmaniasis (CL) is an endemic parasitic disease in Iran. Here, we report an outbreak of zoonotic cutaneous leishmaniasis (ZCL) during the COVID-19 pandemic in Jahrom county, which is an endemic region in the southwest of Iran. Before the pandemic, the annual occurrence of CL was less than 240 cases per year, while the number of cases increased to 307 and 771 cases in the first and second years after the pandemic, respectively. Molecular detection of some isolates identified Leishmania major. The rodent control program was completely interrupted during the first year of the COVID-19 outbreak in Jahrom (February to December 2020), then the program restarted again as routine from the summer of 2021 till now. Interrupted rodent control program along with inadequate screening programs of CL patients were probably one of the causes of this outbreak in Jahrom.