Effect of Concurrent Viral Infection on Systemic and Local Antibody Responses to Live Attenuated and Enhanced-Potency Inactivated Poliovirus Vaccines

To determine the effect of an asymptomatic nonpolioviral infection on the immune response to poliovirus vaccines. —Open comparative trial. —Well-child clinic at The Children's Hospital of Buffalo, NY. —Twenty-seven healthy infants infected with nonpolioviruses and 27 healthy controls matched for age and vaccine group. —Trivalent oral attenuated poliovirus vaccine or enhanced potency inactivated vaccine administered at ages 4 and 12 months. —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. —Concurrent asymptomatic viral infections minimally impaired the immune response to poliovirus vaccines. The adverse effects of coinfection were considered clinically insignificant.