Identification of an Atypical Strain of Toxoplasma gondii as the Cause of a Waterborne Outbreak of Toxoplasmosis in Santa Isabel do Ivai, Brazil

• Published in: The Journal of infectious diseases Vol. 202; no. 8; pp. 1226 - 1233
• Main Authors: Vaudaux, Jean D., Muccioli, Cristina, James, Erick R., Silveira, Claudio, Magargal, Spencer L., Jung, Calvin, Dubey, J. P., Jones, Jeffrey L., Doymaz, Mehmet Z., Bruckner, David A., Belfort, Rubens, Holland, Gary N., Grigg, Michael E.
• Format: Journal Article
• Language: English
• Published: Oxford University of Chicago Press 15.10.2010; Oxford University Press
• Subjects: Animals; Antibodies; Biological and medical sciences; Brazil - epidemiology; Disease Outbreaks; Enzyme-Linked Immunosorbent Assay; Epidemiology; Epitopes; Fundamental and applied biological sciences. Psychology; Genotype; Genotypes; Human protozoal diseases; Humans; Infections; Infectious diseases; Medical sciences; Mice; Microbiology; Parasites; Parasitic diseases; Protozoal diseases; Serology; Serotyping; Species Specificity; Toxoplasma - classification; Toxoplasma - genetics; Toxoplasma - isolation & purification; Toxoplasmosis; Toxoplasmosis - epidemiology; Toxoplasmosis - parasitology; Water Microbiology; South America; Brazil; America; Infection; Protozoa; Apicomplexa; Protozoal disease; Toxoplasma gondii; Toxoplasmosis; Identification; Parasitosis; Strain
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/656397

Multilocus DNA sequencing has identified a nonarchetypal strain of Toxoplasma gondii as the causal agent of a waterborne outbreak in Brazil in 2001. The strain, isolated from a water supply epidemiologically linked to the outbreak, was virulent to mice, and it has previously been identified as BrI. Using a serologic assay that detects strain-specific antibodies, we found that 13 (65%) of 20 individuals who were immunoglobulin (Ig) M positive during the outbreak possessed the same serotype as mice infected with the purported epidemic strain. The remaining 7 individuals, plus additional IgM-negative, IgG-positive individuals, possessed 1 of 4 novel serotypes, the most common of which matched the serotype of mice infected with strains isolated from chickens foraging near the outbreak site. The latter strains likely reflect the genetic diversity of T. gondii circulating in highly endemic regions of Brazil. The serotyping assay proved a useful tool for identification of specific individuals infected with the outbreak agent.