Cutaneous leishmaniasis based on climate regions in Iran (1998-2021): A systematic review and meta-analysis

Abstract

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.

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

“…To date, the state of CL in Iran has shown that provinces such as Fars, Esfahan, Khuzestan, and Ilam always have the highest incidences 5 , 19 , 49 , and the highest prevalence was reported in provinces located in arid regions 50 . The spatial overlap of vectors/reservoirs with CL in these provinces was determined using our studied models.…”

“…The spatial overlap of vectors/reservoirs with CL in these provinces was determined using our studied models. The main goal of vectors and reservoirs spatial analysis is to understand the current epidemiological situation, and the future burden of these diseases 50 . Studies have concluded that leishmaniasis is a climate-sensitive disease, and changes in the environment and distribution of vectors/reservoirs can impact the epidemiology of the disease 19 , 51 .…”