Effect of concurrent viral infection on systemic and local antibody responses to live attenuated and enhanced-potency inactivated poliovirus vaccines.

OBJECTIVE--To determine the effect of an asymptomatic nonpolioviral infection on the immune response to poliovirus vaccines. DESIGN--Open comparative trial. SETTING--Well-child clinic at The Children's Hospital of Buffalo, NY. PARTICIPANTS--Twenty-seven healthy infants infected with nonpolioviruses and 27 healthy controls matched for age and vaccine group. INTERVENTIONS--Trivalent oral attenuated poliovirus vaccine or enhanced potency inactivated vaccine administered at ages 4 and 12 months. MEASUREMENTS/MAIN RESULTS--Neutralizing antibody to poliovirus serotypes 1, 2, and 3 were determined in the serum and nasopharyngeal secretion samples obtained at ages 4, 5, 12, and 13 months. The IgA antibody titers for polioviruses 1, 2, and 3 were measured in nasopharyngeal secretion samples during the same periods. Antibody responses to poliovirus vaccines were similar in coinfected subjects and healthy controls at ages 5 and 13 months, except for serum neutralizing antibody that was significantly elevated in the controls compared with coinfected subjects (geometric mean [+/- SD] antibody titers, 12.7 +/- 1.6 vs 11.5 +/- 1.7). Concurrent viral infections affected the immune response in recipients of the oral poliovirus vaccine and the enhanced-potency inactivated poliovirus vaccine similarly. The immune response to polioviruses 1 and 3 were more adversely affected by coinfection than was the immune response to poliovirus 2. CONCLUSION--Concurrent asymptomatic viral infections minimally impaired the immune response to poliovirus vaccines. The adverse effects of coinfection were considered clinically insignificant.