Prevalence of Cutaneous Leishmaniasis in Khyber Pakhtunkhwa Province of Pakistan: A Case Study

The study was conducted from January 2013 to February 2014 in the dermatology out-patient unit, Kuwait Teaching Hospital (KWH) Peshawar, KPK, Pakistan. KWH is a focal point for CL patients from Peshawar and other parts of the province including adjacent tribal areas.

A total of 4479 CL positive patients, who visited KWH were examined by an expert dermatologist. The suspected clinical diagnosed CL cases were confirmed through microscopy (exudate smears). The lesions of the positive CL patients were punctured with sterile lancets, the exudates were smeared on slides and the diagnosis was done on the basis of direct microscopic visualization of the stained Leishmania amastigotes.

The prevalence of CL in KPK Province of Pakistan and adjacent former tribal areas was calculated in percentage in correlation with nationality, locality, sex, age, and month.

The present study reports the prevalence of CL in human population of KPK province of Pakistan along with the adjacent former tribal areas. The new cases or incidence of CL was reported to be 20.3% (910/4479) in the area while the follow up cases were reported to be 79.7% (3569/4479). A total of 4479 CL infected individuals, both local Pakistanis (4269/4479; 95.31%) and Afghan refugees (210/4479; 4.69%) were reported in this study, who visited KWH from January 2013 to February 2014. The results show that cutaneous leishmaniasis has attained epidemiological proportion in KPK. A similar study conducted from September 2019 to January 2020 has reported 358 CL cases in some selected districts of KPK (Iqbal et al., 2022). A more recent study also reported a total of 3188 microscopically confirmed CL cases in KPK province of Pakistan in 2021, which shows the infection is still increasing and needs more attention (Ullah et al., 2023). Previous studies also reported similar results (Jamal et al., 2013; Samiullah et al., 2009). The reason for higher prevalence among local Pakistanis may be the novelty of the disease in the area, low immunity against CL and large sample size of the local population. The local Pakistanis were not previously exposed to this disease while Afghan refugees were previously exposed to the disease so have develop resistance due to which the infection is more prevalent in locals than war affected Afghan refugees.

Table I shows locality, gender, age and month wise prevalence of CL infected patients in KPK province of Pakistan. The infection was more prevalent in two tehsils of District Khyber of erstwhile FATA viz., Jamrud (41.09%) and Bara (37.95%), while the infection rate was lowest (0.12%) in district Buner. The reason for higher prevalence in tehsil Jamrud and Bara of Khyber is due to the geography, family, and cultural relation of these tribal people with the people of Afghanistan and Afghan refugees residing in different areas of Pakistan.

Table I shows that the CL prevalence rate was higher in males than females. The higher prevalence rate in male is due to their increased vulnerability to the bite of sand flies, which is influenced by factors such as sleeping without shirts during warm seasons and frequent travel to CL endemic areas for employment or other purposes. On the other hand, the females are comparatively protected from sand flies bite as they often use well-covered dresses and are restricted to houses due to Pakhtoon local culture. This may however also depend on gender-related variances in the host response to infectivity (Travi et al., 2002). Previous studies conducted by Jamal et al. (2013), Samiullah et al. (2009) and Nawaz et al. (2010), also reported similar higher infection in males. Some studies attributed the gender difference observed in some parasitic disease to hormonal effects (Bailey and Diana, 2007; Khan and Muneeb, 2005; Kassiri et al., 2012).

Table I. Age-wise, gender-wise, locality-wise and month-wise prevalence of cutaneous leishmaniasis in Khyber Pakhtunkhwa, Pakistan.

Table I also shows the prevalence of cutaneous leishmaniasis in different age groups. The highest age specific prevalence of CL was recorded in patients with age group of 0-9 years with an infection rate of 38.09%, and the lowest prevalence rate was observed in patients having age group of above 60 years (2.03%). Previously Nawaz et al. (2010) had reported that CL affect more cases in the age group of 0-9 years, wheras Jamal et al. (2013) have shown that most highly infected age group with CL is person of 11-20 years old. The reason for highest infection rate in the children is due to their more outdoor activities and less developed immune systems.

Considering month-wise prevalence of CL (Table I), the highest prevalence rate was reported in the month of March 2013 (11.74%), which the lowest prevalence rate of infection was recorded in the month of August 2013 (3.28%). The prevalence of CL fluctuates significantly throughout the year with the highest rates occurring during the initial three months of the year i.e. in winter season. This fluctuation pattern is attributed to increased activity of sand flies during warm seasons (June to September), particularly in temperate regions like Pakistan (Majidnia et al., 2023). The infected sand flies transmit the disease during their active months which results in appearance of symptoms in the subsequent winter and spring seasons.

Major risk factors associated with CL are poor socioeconomic conditions, poor housing and poor sanitary conditions, high temperature and high humidity, domestic animals and pets, non-meshed windows in living rooms, exposed body parts and uncovered sleeping habits, non-use of insect repellents and nets, outdoor activities in dawn and dusk, environmental changes and population displacement, and malnutrition as reported in our previous study (Jamal et al., 2013) as well as other researchers (Alzahrani et al., 2023; Lana et al., 2021; Ullah et al., 2016). According to these reports, about 70-80% of the infected individuals were found to be infected due to the mentioned risk factors. The sandflies are nocturnal and are more active from dusk to dawn when temperature falls and humidity rises (Lawyer and Perkins, 2000) so those individuals who are performing outdoor activities in these times are more susceptible to sandfly bites and subsequent leishmaniasis infection.

This study concludes that CL is emerging as a major public health problem in KPK province of Pakistan. The infection was found to be more prevalent among male local population with maximum cases in Jamrud and Bara tehsils of Khyber Agency. Children were found to be more susceptible to get infected with appearance of symptoms mostly in the months of January-March. The measures for prevention of sandfly bites and improving socioeconomic and sanitary conditions play an important role in preventing the infection.

The study received no external funding.

The study was approved by Ethics Committee of University of Peshawar. The informed consent was taken from all participants for which a specially designed proforma was used containing information regarding name of the patient, father’s name, gender, age, nationality, locality, family history, diagnosis, treatment and follow up schedule.

The authors have declared no conflict of interest.