Molecular Epidemiology of American Tegumentary Leishmaniasis in Panama

Abstract

Abstract. American tegumentary leishmaniasis is an increasing public health problem in Panama. This study describes the clinical characteristics and the molecular epidemiology of leishmaniasis in Panama over a 5-year period (2004)(2005)(2006)(2007)(2008). Additionally, we applied a polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) -based assay to identify Leishmania species in clinical isolates, skin scrapings, and sandflies specimens. Whereas 60.3% of cases were detected with conventional parasitologic techniques (smear or in vitro culture), the PCR detected 72% positive patients. Our clinical-epidemiologic data corroborate the high incidence of L. ( Viannia ) panamensis and provide evidence of peridomestic and/or domestic transmission. Mucosal involvement was observed in 4.2% of the patients. The overall natural infection rate with Leishmania in 103 pools of sandflies was 0.46%. Lutzomyia gomezi and Lutzomya panamensis were the prevalent species incriminated as vectors at the capture sites in central Panama. This study contributes to a better knowledge of the current epidemiology of tegumentary leishmaniasis in Panama.

Clinical Cutaneous Leishmaniasis Rates Are Associated with Household Lutzomyia gomezi, Lu. Panamensis, and Lu. trapidoi Abundance in Trinidad de Las Minas, Western Panama

“…Our observations emphasize patterns already described in Panama, 2 and expected in light of the fundamental role vectors play on the transmission of Leishmania spp. parasites, 5 where the abundance of sand flies is closely associated with clinical Leishmania infections, even considering the potential bias introduced by the clinical diagnoses.…”

“…Similar patterns have reported elsewhere in Latin America. 9,10 Lutzomya gomezi, the vector presenting the best association with household clinical ACL rates, has previously been reported as major vector in Panama 2,5,11 and Latin America. 10 In recent years an average of 2,188 clinical ACL cases have been reported in Panama, 1 although a 50% underestimation in this number is highly likely.…”

“…The possible causes of these "hot spots" are unclear, and may be related to emerging ecological and environmental changes. 2,3 We are currently analyzing our vector samples to determine parasite infection rates and to evaluate insecticide thermal fogging impacts on sand fly abundance at Trinidad de Las Minas, in studies subsequent to this one. Nevertheless, the association of sand fly abundance with clinical ACL household rates highlights the need to better understand the ecology of sand flies, for example, which factors underpin the domiciliary abundance, and also for the development of new strategies for phlebotomine sand fly control.…”

“…1 Disease burden is primarily concentrated in the most socially excluded populations of Panama, a pattern common in Central America. 2,3 In Panama ACL control is focused on the clinical treatment of human patients with skin lesions, without considering active surveillance and sand fly control. 2 Nevertheless, the increased evidence for domicilary and peridomiciliary transmission calls for improving current vector control strategies.…”

Current Knowledge of Leishmania Vectors in Mexico: How Geographic Distributions of Species Relate to Transmission Areas

“…25,26 In northern Mexico and the southern United States, sand fly species suspected of being involved in parasite transmission to humans are Lu. diabolica and Lu.…”