Leishmaniasis

Leishmaniasis is caused by a protozoa parasite that can be transmitted by over 90 sandfly species. There are 3 main forms of the disease: Visceral leishmaniasis (VL), Cutaneous leishmaniasis (CL), and Mucocutaneous leishmaniasis.

Situation in Pakistan

In Pakistan, leishmaniasis has been reported in human and animal population. Human-CL is the second most prevalent vector-borne disease in the country after malaria. There are 37 out of 70 species of the sand-fly inhabitant in Pakistan, which can transmit disease to healthy hosts. Endemic areas of disease in Pakistan include areas of Baluchistan, Interior Sindh, South Punjab, and Khyber Pakhtunkhwa. In 2020 over 85% of new CL cases occurred in 10 countries and Pakistan was one of them.

Anthroponotic Cutaneous Leishmaniasis occurs in many parts of the country although its precise distribution and prevalence cannot be determined because of inadequate information. It has been reported from many towns in Khyber Pakhtunkhwa (Peshawar, Mardan, Kohat and Abbottabad) and Baluchistan (Quetta, Mastung and Peshin), and even in the suburbs of Islamabad and Rawalpindi. The main cause of the increase in cases of ACL seems to be the mass migration of the population from endemic (certain areas of Afghanistan) to non-endemic areas.  

Zoonotic Cutaneous Leishmaniasis occurs in many parts of the country being widespread over a large area in Baluchistan province. The incidence is high among children in the indigenous population, whereas adults are generally immune as a result of contact with the parasite during their childhood.  

During the first quarter of 2022, the Federal Ministry of Health in Pakistan reported an increase in the number of cutaneous leishmaniases cases in Baluchistan province. Overall, 4318 leishmaniases cases were reported, the majority of which are women and children. Also, around 2,000 new cases of leishmaniasis have been reported from Karak, Khyber Pakhtunkhwa pushing up the total number of cases in the province to 5,000.

Vaccine and Treatment Status

Working with the Ministry of Health, Médecins Sans Frontières (MSF) opened a dedicated treatment center in Peshawar’s Naseerullah Babar Khan memorial hospital in May 2018 and later at Banu district headquarters hospital to address the dire needs in Khyber Pakhtunkhwa’s southern districts. The facility is operating at full capacity, with patient numbers continuing to increase. They reported a cure rate of more than 95 per cent in 2019 and are constantly seeing more and more patients, which also demonstrates the heavy needs in the province.

To date, there are no vaccines against leishmaniasis, and control measures rely on chemotherapy to alleviate disease and on vector control to reduce transmission. A few candidate vaccines are undergoing trials still, but none has received an approval from any regulatory authority. A review published in 2019 stated that first generation vaccines (Leishmune and CaniLeish) generated robust protective immunity in dogs. In human, recombinant vaccines, including Leish-F1 could confer some degrees of protective immunity against natural infection. Recently, ChAd63-KH DNA vaccine has been accomplished in providing prevention against Leishmania infection; however, this vaccine will be further evaluated in other clinical trials.

Meglumine antimoniate, the first-line treatment for cutaneous leishmaniasis, is not produced locally in Pakistan. The health authorities therefore rely largely on imports by international organizations such as the World Health Organization and MSF. In many settings the doses each patient receives are insufficient, because of the drug’s limited availability and the lack of suitably trained medical staff.

Involvement of Organizations and Livestock Sector in Disease Control

There is no proper reporting or recording system. Cases seen by public sector hospitals are reported to central hospitals, then to an office at the Malaria Control Directorate. Some 25,000 cases are reported annually, but an estimated 70% are not seen in the public sector. The Directorate of Malaria has been assigned to take the lead role in the control of this disease, while it has also proposed incorporating responsibility for dengue control. Beyond passive case detection and treatment, no control measures are active. A surveillance system needs to be established in order to fully evaluate the problem.

There is a general requirement for better understanding of the dynamics of the disease in Pakistan, and the measures for controlling it. Operational research is required in all aspects of case management and control including studies on vectors and reservoirs of infection. Resources need to be allocated for case management and control.