Outbreak of toxoplasmosis with pulmonary involvement in immunocompetent military population.

An outbreak of toxoplasmosis with pulmonary involvement occurred in immunocompetent military personnel in the Colombian Amazon.

• Four cases were identified, all without known immunosuppression.
• The outbreak occurred during a military training exercise in a rainforest area of Colombia.
• All cases were confirmed by serology.
• The exposure source was common to all patients in the Colombian Amazon region.

One of the four patients developed severe complications including hypoxemic ventilatory failure and myocarditis.

• This case represented the most severe presentation among the four military personnel.
• Hypoxemic ventilatory failure and myocarditis occurred as complications of toxoplasmosis in an immunocompetent host.
• This demonstrates that severe multi-organ involvement can occur in the absence of known immunosuppression.

Toxoplasmosis with pulmonary involvement was diagnosed in immunocompetent patients from a rainforest area of Colombia.

• All four patients lacked known immunosuppression, distinguishing this presentation from typical severe toxoplasmosis seen in immunocompromised individuals.
• Pulmonary involvement was present in all four cases.
• The diagnostic process included serology for confirmation.
• The parasite's genotypic variants were discussed as relevant to disease severity, given that atypical genotypes circulate in South America.

The probability of toxoplasmosis causing disease is related to both alterations in the immune system and the parasite's virulence.

• The authors highlight that virulence of the parasite, in addition to host immune status, determines disease expression.
• Genotypic variants of Toxoplasma gondii are discussed as important factors in pathogenicity.
• Atypical genotypes found in the Amazon region are associated with more severe disease even in immunocompetent hosts.