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Prior to 1999, Ghana was not known to be a Cutaneous Leishmaniasis (CL) endemic country. The outbreak of CL in the Volta Region in 1999 resulted in the need for urgent investigations to understand the disease transmission dynamics. Monthly entomological collections from January 2006 to May 2007 revealed 99.8% (21,980/22,016) of sand flies collected were Sergentomyia and 0.2% (36/22,016) Phlebotomus, the putative vector of CL in the Old World. The density of Phlebotomus was so low, their vectorial role is uncertain. This study was therefore aimed at determining the possible vector species in the outbreak area. We collected sand flies from homes to examine anthropophily, by testing their blood meals. The blood-meal sources of 275 (20.5%) of 1342 collected female sand flies revealed the highest proportion of animal blood source was chicken (33.8%) and goat (12.4%). Humans accounted for 32% of blood meal sources. Identified species included: Sergentomyia africana africana (26.9%), S. ingrami (34.5%) and S. simillima (38.2%), which were found to have single and mixed blood-meals, with S. simillima having the highest proportion that contained human blood (14.6%). Using molecular methods, we examined unfed flies and flies found anthropophilic for the presence of Leishmania major DNA. Poolscreening analysis revealed 3 pools of S. ingrami positive with L. major DNA, with an infection rate of 1.27% (95% confidence interval: 2.467–3.647). This study showed that some Sergentomyia species are anthropophilic, contain L. major DNA, and could be involved in the transmission of CL in Ghana. There is however the need to conclusively validate the role of S. ingrami as a vector of L. major in Ghana, by isolating the parasite and initiating experimental transmission studies.

Human cutaneous leishmaniasis (CL) has previously been reported in West Africa, but more recently, sporadic reports of CL have increased. Leishmania major has been identified from Mauritania, Senegal, Mali, and Burkina Faso. Three zymodemes (MON-26, MON-117, and MON-74, the most frequent) have been found. The geographic range of leishmaniasis is limited by the sand fly vector, its feeding preferences, and its capacity to support internal development of specific species of Leishmania. The risk of acquiring CL has been reported to increase considerably with human activity and epidemics of CL have been associated with deforestation, road construction, wars, or other activities where humans intrude the habitat of the vector. In the Ho Municipality in the Volta Region of Ghana, a localised outbreak of skin ulcers, possibly CL, was noted in 2003 without any such documented activity. This outbreak was consistent with CL as evidenced using various methods including parasite identification, albeit, in a small number of patients with ulcers. This paper reports the outbreak in Ghana. The report does not address a single planned study but rather a compilation of data from a number of ad-hoc investigations in response to the outbreak plus observations and findings made by the authors. It acknowledges that a number of the observations need to be further clarified. What is the detailed epidemiology of the disease? What sparked the epidemic? Can it happen again? What was the causative agent of the disease, L. major or some other Leishmania spp.? What were the main vectors and animal reservoirs?What are the consequences for surveillance of the disease and the prevention of its reoccurrence when the communities see a self-healing disease and may not think it is important? Keywords: cutaneous leishmaniasis; Ghana; Volta Region; West Africa; outbreak; follow-up (Published: 13 July 2011) Citation: Global Health Action 2011, 4 : 5527 - DOI: 10.3402/gha.v4i0.5527

We report first-time definitive evidence of human cutaneous leishmaniasis (CL) resulting from L. major infections in Ghana. The evidence is in the form of PCR testing and DNA sequence analysis of skin sample biopsies from residents of the Ho District in the forested Volta Region of southeastern Ghana (Figure 1). The moist semi-deciduous forest of this region of Ghana is atypical for CL. Although two sand fly species with known or suspected potential to transmit L. major were present in communities where human cases of CL originated, they were found in such small numbers that their role in the transmission of CL is uncertain. Twelve million people worldwide are believed to be infected with the parasites that cause leishmaniasis, and 88 different nations report this disease. 1 It is estimated that up to 75% of the 1.5 million new cases of leishmaniasis that occur each year are CL with L. major the responsible etiologic agent of this cutaneous disease in Africa and throughout Eurasia. Over this vast range, CL transmission is typically associated with arid desert and savannah conditions where the parasites are harbored in rodents and vectored by night-biting sand flies of the genus Phlebotomus. For many years, leishmaniasis in Africa and Western Asia has been grossly underestimated; it now appears that the disease is much more prevalent than previously suspected. 1 In Ghana, CL was considered a parasitic disease risk that was limited to the arid sahel-savannah region in the north, but no infections or evidence of transmission had been actually described. Thousands of man-hours of mosquito surveillance have been conducted in northern Ghana 2 for the purpose of quantifying man-biting malaria vectors, but there is no record or report of sand flies in these collections. However, since 1999, an increasing number of suspected CL cases have been reported from the southern Volta Region of Ghana in a moist forest ecosystem where such skin lesions had not been previously reported. The assumption of CL was based subjectively on local microscopy, which identified Leishmania amastigotes in skin lesion biopsies taken from a cluster of local patients. Between 1999 and 2002, the Ghana Health Service recorded 2,426 suspected cases of CL in the Ho, Hohoe, and Kpando Districts (2,348, 2, and 76 cases, respectively). In 2003, the number of suspected cases rose to 6,450 (6,185, 174, and 91 in the same respective districts) with 116 villages affected (Ghana Ministry of Health (MoH), Annual Report, 2003). A limited survey of towns in the Ho district during 2002 identified suspected CL lesions in 12.2–32.3% of local school children. In an effort to determine the cause and extent of the outbreak, the Ghana MoH initiated an epidemiologic study in Ho district with assistance from the U.S. Naval Medical Research Unit No. 3 and the Noguchi Memorial Institute of Medical Research. Initial efforts of our study intended to verify the presence of Leishmania parasites by applying newly developed PCR methods to 5 previously collected, archived biopsy samples