Outbreak of Cutaneous Leishmaniasis in Peruvian Military Personnel Undertaking Training Activities in the Amazon Basin, 2010

Abstract

Military personnel deployed to the Amazon Basin are at high risk for cutaneous leishmaniasis (CL). We responded to an outbreak among Peruvian Army personnel returning from short-term training in the Amazon, conducting active case detection, lesion sample collection, and risk factor assessment. The attack rate was 25% (76/303); the incubation period was 2-36 weeks (median = 8). Most cases had one lesion (66%), primarily ulcerative (49%), and in the legs (57%). Real-time polymerase chain reaction (PCR) identified Leishmania (Viannia) braziliensis (59/61 = 97%) and L. (V.) guyanensis (2/61 = 3%). Being male (risk ratio [RR] = 4.01; P = 0.034), not wearing long-sleeve clothes (RR = 1.71; P = 0.005), and sleeping in open rooms (RR = 1.80; P = 0.009) were associated with CL. Sodium stibogluconate therapy had a 41% cure rate, less than previously reported in Peru (~70%; P < 0.001). After emphasizing pre-deployment education and other basic prevention measures, trainees in the following year had lower incidence (1/278 = 0.4%; P < 0.001). Basic prevention can reduce CL risk in deployed militaries.

Figure 1.

Map of Alto Amazonas in the northern Peruvian Amazon basin. Map shows the three sites (A, B, and C) where military personnel undertook short-term survival training. Dark lines show the border between the San Martin and Loreto departments and blue lines show river beds. Global positioning system (GPS) coordinates were intentionally removed for being considered sensitive information.

Figure 2.

Epidemic curve for confirmed cutaneous leishmaniasis during the outbreak. The curve was constructed based on self-reported dates when individuals first noticed their skin lesions. Eight of the 76 confirmed cases of leishmaniasis (11%) were excluded because of incomplete data.