Table 3. Arguments for and against the intrafamilial transmission of Tropheryma whipplei, France, 2003–2011.

Argument in favor	Argument against
Epidemiologic
T. whipplei carriage is significantly more common in persons related by genetics and marriage (34%) than in the general population of France (2%–4%)	Presence of few different bacterial genotypes in some families
Significant detection of the same bacterial genotypes in most families
Most persons did not live in the same household and had contact only during family gatherings in different places
Microbiologic
Positive serologic results in relatives (77%) significantly higher than in the general population of France (48%)