Vann sez, “As a follow-up to Cory’s entry in January of last year on how toxoplasmosis may alter people’s moods (women become more friendly; men become more paranoid), recent studies suggest that infection by the parasite may also cause people to become more prone to feeling guilty, develop schizophenia, have auto accidents, or be born male.”
U.S. Geological Survey biologist Kevin Lafferty has linked high rates of toxoplasmosis infection in 39 countries with elevated incidences of neuroticism, suggesting the mind-altering organism may be affecting the cultures of nations.
Stranger still, parasitologist Jaroslav Flegr of Charles University in Prague thinks T. gondii could also be skewing our sex ratios. When he looked at the clinical records of more than 1,800 babies born from 1996 to 2004, he noted a distinct trend: The normal sex ratio is 104 boys born for every 100 girls, but in women with high levels of antibodies against the parasite, the ratio was 260 boys for every 100 girls. Exactly how the parasite might be tipping the odds in favor of males isn’t understood, but Flegr points out that it is known to suppress the immune system of its hosts, and because the maternal immune system sometimes attacks male fetuses in very early pregnancy, the parasite’s ability to inhibit the immune response might protect future boys as well as itself.
See also:
Increase in guilt proneness
Risk of traffic accidents
Sex ratio (registration required)
(Thanks, Vann!)