Mycoplasma pneumoniae and Chlamydia pneumoniae strain TWAR infections in U.S. Marine Corps recruits.

Paired sera from 208 healthy Marine Corps recruits undergoing 11 weeks of basic training in San Diego during 1989 were studied by complement fixation and microimmunofluorescence techniques for antibody to Mycoplasma pneumoniae and Chlamydia pneumoniae strain TWAR infections. Upon entering training, 52.7% and 64.4% of the recruits had evidence of prior infection with M. pneumoniae and C. pneumoniae, respectively. At the end of training, 5.9% of recruits had evidence of new infections with M. pneumoniae (4-fold antibody rise) and 3.8% had evidence for new infections with C. pneumoniae (4-fold antibody rise). Recruits with evidence of previous infection with C. pneumoniae had a lower relative odds of new infection during training with this agent (odds ratio = 0.07, 95% confidence interval 0.00-0.61). These data demonstrate that, like their counterparts in Scandinavia, U.S. military recruits also suffer from C. pneumoniae infections. Both M. pneumoniae and C. pneumoniae should be considered as potential causes of respiratory disease among U.S. military trainees.