Prevalence of IgG and IgM antibodies to Toxoplasma gondii in forensic blood samples from different causes of death in central Andes region in Colombia

Introduction: The objective of this study was twofold: first, to evaluate the method of sample collection that would enable the measurement of antiToxoplasma antibodies in forensic samples, and second, to report the prevalence of antibodies in deceased individuals due to traffic accidents, homicides, and suicides who are brought to the National Institute of Legal Medicine and Forensic Sciences, Western Regional Office (INMLCF) in Armenia, Manizales and Pereira, cities located in the center andes region of Colombia. Methods: Initially, we assessed the feasibility of measuring antibodies on filter paper or in Vacutainer tubes. Serum samples from 15 voluntary individuals were collected as controls, and the measurement of antibodies on filter paper was compared with the same samples collected in Vacutainer tubes after two days at room temperature. Subsequently, 42 blood samples were collected from forensic cases involving various causes of death in Manizales, Armenia, and Pereira. Measurement of antiToxoplasma IgG and IgM antibodies was performed using the VIDAS II kit from Biomerieux (R). Results: The volunteer samples consistently tested negative when using filter paper, whereas their positivity was preserved when collected in Vacutainer tubes and before 48 h after death. Therefore, the forensic samples were collected using Vacutainer tubes. Out of the 42 forensic blood samples, 19 (45.2 %) tested positive for IgG antiToxoplasma antibodies. All samples tested negative for IgM antiToxoplasma antibodies. A significant association was observed between antibody positivity and the city of origin, while deaths due to traffic accidents showed a negative association with toxoplasmosis. Conclusions: We found that filter paper was unsuitable for collecting samples for post-mortem serological studies. The positivity of antibodies varied significantly depending on the city, and in Manizales, deaths resulting from traffic accidents were not associated with toxoplasmosis.