Toxoplasmosis in military personnel involved in jungle operations

Abstract

Tropical diseases, mainly leishmaniasis and malaria, increased among Colombian military personnel due to intensive operations in the jungle in the last ten years; as a result the Colombian army developed important preventive strategies for malaria and leishmaniasis. However, no knowledge exists about toxoplasmosis, an emergent disease in military personnel. We compared the prevalence of IgG anti-Toxoplasma antibodies by ELISA and of parasitaemia by a real time PCR assay, in 500 professional soldiers that operated in the jungle with a group of 501 soldiers working in an urban zone (Bogotá). We found that the prevalence was significantly different between both groups of soldiers (80% in soldiers operating in jungle vs. 45% in urban soldiers, adjusted OR 11.4; CI 95%: 3.8–34; p < 0.0001). All soldiers operating in the jungle drink unboiled and chlorine untreated lake or river water. In urban soldiers, these risk factors along with eating wild animal meat or eating tigrillo (little spotted cat) were significantly associated with a higher prevalence. Characteristic toxoplasmic choriorretinal lesions were found in 4 soldiers that operated in the jungle (0.8%) and in one urban soldier (0.19%). All soldiers before being deployed in jungle operations should be tested for Toxoplasma antibodies and to receive adequate health information about the routine use of personnel filters to purify their water for consumption.

Introduction

Governmental anti-guerrilla operations during the last ten years in Colombia have largely increased the number of soldiers that remain operative during months and even years, in the jungle. These operations occur mainly in the southern Amazonia region of Colombia (departments of Meta, Guaviare, Vichada, Cáqueta, Amazonas y Putumayo) and involve 32,000 men (Perez, 2004). Consequently, tropical diseases, such as leishmaniasis and malaria have increased among military personnel and the Colombian army developed important preventive strategies for both diseases. Among these tropical diseases, toxoplasmosis emerged as responsible for outbreaks of febrile disease. In 2009, one toxoplasmic outbreak was reported in Colombia, involving 20 immunocompetent soldiers from the same unit that operated in the jungle (Pino et al., 2009). These cases showed general signs, fever, adenopathies, one of them had myocardiopathy with pericarditis and impaired ventricular function and two of them required ventilator assistance at the intensive care unit due to acute respiratory insufficiency (Pino et al., 2009). However, no knowledge exists as to the overall risk for toxoplasmosis in Colombian military personnel operating in the jungle, and there are no epidemiological reports in the medical literature in military personnel about which risk factors could be involved in their acquisition. Therefore, we studied soldiers operating in two different geographical regions and analyzed the risk factors associated with prevalence and the frequency of ocular lesions in these personnel.