The epidemiology of leishmaniases in Lebanon

Prevalence of cutaneous Leishmaniasis in the Middle East: a systematic review and meta-analysis

Cutaneous leishmaniasis (CL), caused by an obligate intracellular protozoan parasite from the genus Leishmania, imposing a significant burden on underdeveloped countries especially those located in the Middle East. Four electronic databases were searched to evaluate the prevalence of CL in the Middle East. The random effects model (95% confidence intervals (CI)) were applied to determine the overall and subgroup pooled prevalence. Heterogeneity was assessed by Cochran's Q test and I2 statistics. Among 2424 peer-reviewed papers, 37 datasets from 34 studies were included in the current meta-analysis. 285560 individuals were assessed across 9 Middle Eastern countries. The pooled prevalence of CL was estimated at 12% (95% CI 9-15 %; 10718/285560). The highest prevalence rate was observed in Syria (39%, 37-42%), and the lowest one was found in Iraq and Lebanon (0%, 0-1%). The prevalence of CL in studies that applied LST assays had the highest rate (48%, 17-80%). The infection rate in males was similar to females (7%, 4-10%). The prevalence of infection in individuals living in urban areas was higher than in rural areas (14%, 10-19%). The prevalence of CL in the age group 0-15 years was higher than in individuals 16-40 and >40 years (9%, 6-13%). Most of the lesions were found on the face, and single lesions were more prevalent than two and three ones. In conclusion, the occurrence of CL was considerable in Middle Eastern countries. Therefore, more efforts should be made to precisely report the CL in this region for developing appropriate preventive and controlling strategies.  .

Cutaneous leishmaniasis in north Lebanon: re-emergence of an important neglected tropical disease

Background

Cutaneous leishmaniasis (CL) is the most prevalent neglected tropical disease among externally displaced people in the Middle East. In recent years, the Lebanese population has increased >30%, mainly due to a mass influx of Syrian migrants, thousands of them carrying CL, among other infectious diseases. Here we revisit the current CL prevalence among refugees in northern Lebanon.

Methods

This cohort study was conducted at the Al Bashaer Medical Center in north Lebanon between January and June 2017. A total of 48 randomly selected suspected CL patients were clinically diagnosed by dermatologists and samples were obtained for microscopic examination and molecular identification by polymerase chain reaction restriction fragment length polymorphism. The treatment response to antimonials was assessed each week and was followed for up 6 months.

Results

Leishmania tropica was the predominant species (91.7%) followed by Leishmania major (8.3%). Confirmed cases were treated with one to two courses of antimonials and healing was usually achieved after receiving a second course of treatment. Importantly, we show evidence of possible local CL transmission by indigenous sandflies in three separate patients who had no history of recent travel to Syria.

Conclusions

This highlights the urgent necessity to implement preventive disease strategies to avoid further dispersion of L. tropica CL in north Lebanon.

Fatal Visceral Leishmaniasis Caused by Leishmania infantum, Lebanon

Visceral leishmaniasis, a fatal disease if not treated, is caused by Leishmania parasites. This disease might be overlooked in the Middle East because of limited awareness and low incidence. We report 5 patients who died of visceral leishmaniasis in Lebanon and make recommendations to improve faster diagnosis and treatment.

Revisiting leishmaniasis in the time of war: the Syrian conflict and the Lebanese outbreak

BACKGROUND

Leishmaniasis is a neglected tropical disease, endemic in many worldwide foci including the Middle East. Several outbreaks have occurred in the Middle East over the past decades, mostly related to war-associated population migration. With the start of the Syrian war, the frequency and magnitude of these outbreaks increased alarmingly. We describe the epidemiology of Leishmania infection in Lebanon and the most recent outbreak relevant to the Syrian war.

METHODS

We reviewed all leishmaniasis cases reported to the Epidemiologic Surveillance Department at the Lebanese Ministry of Public Health between 2001 and the first quarter of 2014. The demographics and distribution of Syrian refugees in Lebanon were linked to reports of new Leishmania cases.

RESULTS

In total, 1033 new cases of leishmaniasis were reported in 2013 compared to a previous annual number in the range of 0-6 cases. The majority of cases reported in 2013 involved Syrian refugees and their relevant areas of concentration.

CONCLUSIONS

This new outbreak of leishmaniasis in Lebanon is the first of its kind for more than a decade. The sudden increase in Leishmania cases in Lebanon in 2013 is attributed to the increasing numbers and wide distribution of Syrian refugees in Lebanon. This serves as an example of the risks associated with military conflicts and the ability of communicable diseases to cross borders.

Alternative and complementary antileishmanial treatments: assessment of the antileishmanial activity of 27 Lebanese plants, including 11 endemic species

Aqueous, methanolic, and dichloromethane extracts from 27 Lebanese plants were investigated for their in vitro immunomodulatory and antileishmanial activities as compared to their toxicity against human cells. Extracts from yellow chamomile (Anthemis tinctoria), white larkspur (Consolida rigida), Syrian broom (Cytisus syriacus), coast spurge (Euphorbia paralias), shield fibigia (Fibigia clypeata), Auchers golden-drop (Onosma aucheriana), shell-flower sage (Salvia multicaulis), snowy woundwort (Stachys nivea), Palestine woundwort (Stachys palaestina), and polium-leaved speedwell (Veronica polifolia) exhibited interesting antileishmanial activities on the intracellular amastigote form of the parasite, while several extracts from A. tinctoria, F. clypeata, and O. aucheriana were shown to induce nitrous oxide (NO) production by human macrophages. Further experiments should be performed in order to purify and characterize the chemical compounds responsible for these activities.

Identification of Lebanese dermotropic putative Leishmania archibaldi isolates by gp63 PCR-RFLP

Leishmania stocks isolated from cutaneous lesions in Lebanon were characterized by PCR methods. The stocks were typed as putative L. (L.) archibaldi (gp63 PCR-RFLP), belonging to 2 different genotypes (PCR-based schizodeme analysis). This constitutes the first report on the presence of L. (L.) archibaldi in the Middle East.