Decrease of psychomotor performance in subjects with latent 'asymptomatic' toxoplasmosis

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Havlíček, J. ; Gašová, Z. ; Smith, Andrew Paul ; Zvára, K. ; Flegr, J. (2001)

Toxoplasma gondii is known to induce specific behavioural changes in its intermediate hosts. This is usually considered to be an evolutionary adaptation aimed to increase the probability of transmission of the parasite into its definitive host, the cat, by predation. In rodents an increase of reaction time as well as many other specific behavioural patterns have been observed. Here we report the results of our double blind study showing the significantly longer reaction times of 60 subjects with latent toxoplasmosis in comparison with those of 56 controls. Moreover, the existence of a positive correlation between length of infection and mean reaction time suggested that slow and cumulative effects of latent toxoplasmosis rather than a one-step (and possibly transient) effect of acute toxoplasmosis disease are responsible for the decrease of psychomotor performance of infected subjects. To our knowledge, this is the first study confirming the existence of such parasite-induced changes in human behaviour that could be considered in evolutionary history of the human species as adaptive from the point of view of parasite transmission.
  • References (39)
    39 references, page 1 of 4

    arendt, g., von giesen, h. j., hefter, h., neuen-jacob, e., roick, h. & jablonowski, h. (1999). Long-term course and outcome in AIDS patients with cerebral toxoplasmosis. Acta Neurologica Scandinavica 100, 178±184.

    arsenijevic, d., girardier, l., seydoux, j., chang, h. r. & dulloo, a. g. (1997). Altered energy balance and cytokine gene expression in a murine model of chronic infection with Toxoplasma gondii. American Journal of Physiology 272, E908±E917.

    berdoy, m., webster, j. p. & macdonald, d. w. (2000). Fatal attraction in rats infected with Toxoplasma gondii. Proceedings of the Royal Society of London, B 267, 591±594.

    derouin, f., gluckman, e., beauvais, b., devergie, a., melo, r., monny, m. & lariviere, m. (1986). Toxoplasma infection after human allogeneic bone marrow transplantation : clinical and serological study of 80 patients. Bone Marrow Transplantation 1, 67±73.

    develoux, m., candolfi, e., hango-dounbo, s. & kien, t. (1988). La toxoplasmose au Niger. Bulletin de la socieU teU de Pathologie Exotique 81, 253±259.

    figueiredo, j. f., moyses-neto, m., gomes, u. a., suaid, h., ferraz, a. s., martins, a. c. & fiorillo, a. m. (1983). Antibody titers to Toxoplasma gondii in renal transplant patients. Brazilian Journal of Medical and Biological Research 16, 235±239.

    flegr, j. & havli! c)ek, j. (1999). Changes in the personality pro®le of young women with latent toxoplasmosis. Folia Parasitologica (Praha) 46, 22±28.

    flegr, j. & hrdy! , i. (1994). In¯uence of chronic toxoplasmosis on some human personality factors. Folia Parasitologica (Praha) 41, 122±126.

    flegr, j., kodym, p. & tolarova! , v. (2000). Correlation of duration of latent Toxoplasma gondii infection with personality changes in women. Biological Psychology 53, 57±68.

    flegr, j., zitkova! , s., kodym, p. & frynta, d. (1996). Induction of changes in human behaviour by the parasitic protozoan Toxoplasma gondii. Parasitology 113, 49±54.

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