Administering the herpes zoster and pneumococcal vaccines to patients during the same visit does not appear to compromise the effectiveness of the zoster vaccine, despite a 2009 edict that the two should not be given together.

Investigators reached this conclusion based on a 3.5-year observational study of two cohorts from Kaiser Permanente Southern California. Researchers there evaluated data from 7,187 people who received the vaccines on the same day and 7,179 people who received the pneumococcal vaccine within one year to 30 days prior to zoster vaccination. The study period extended from January 2007 through June 2010.

In 2009, the zoster vaccine package insert was revised to include a statement that the vaccine should not be administered with the pneumococcal vaccine, because concomitant use resulted in reduced immunogenicity of the zoster vaccine, decreasing its protective effect against shingles. In general, administering vaccines during the same patient visit increases coverage levels and minimizes administration costs.

Electronic health records showed that 56 incident cases of shingles occurred in the co­administration cohort and 58 in the nonconcomitant group, yielding a herpes zoster incidence of 4.54 and 4.51 per 1,000 person-years, respectively. The difference was not statistically significant.

“We found no evidence of an increased risk of [herpes zoster] in the population receiving zoster vaccine and pneumococcal vaccine concomitantly,” the researchers wrote. “The revision of the product information needs to be carefully assessed to avoid introducing barriers to patients and providers who are interested in these two important vaccines.”

Tseng HF et al. Vaccine. 2011;29:3628-3632