The influence of immunity on raw milk--associated Campylobacter infection
M. J. Blaser, E. Sazie and L. P. Williams Jr
After a retreat to an Oregon farm, 19 of 31 college students developed an
acute gastrointestinal illness. Campylobacter jejuni infection was
recognized in all the ill students and caused asymptomatic infections in
three others. In total, 22 (88%) of 25 students who consumed raw milk for
the first time became infected as compared with none of two who had not
consumed raw milk. Among ten persons who chronically consumed raw milk,
none was ill, a striking difference from the 76% attack rate among the 25
acutely exposed students. The quantity of raw milk consumed was directly
related to the occurrence and severity of illness. Acutely infected
students showed significant rises in C jejuni-specific immunoglobulins,
whereas the low antibody levels seen in unexposed persons did not rise. In
contrast, acute-phase serum samples from persons with chronic exposure to
raw milk showed elevated antibody levels to C jejuni. These findings
indicate that chronic raw milk consumption is associated with elevated
levels of C jejuni-specific serum antibodies and with immunity to
symptomatic infection.
