Fewer than four injections with the pneumococcal vaccine are equally effective for reducing nasal pneumococci in vaccinated babies. Researchers from University Medical Center (UMC) Utrecht, the Netherlands Vaccin Institute (NVI) in Bilthoven and the Spaarne Hospital in Hoofddorp describe this in their article published this week in the journal JAMA. Pediatric immunologist, Professor Lieke Sanders of UMC Utrecht led this research.
In the study, Sanders and colleagues followed one thousand babies for a period of two years. Babies in one group were given three vaccinations, in another group, only two and in the third group were only vaccinated at the age of two years. The results showed that babies who received three or even only two vaccinations had sixty percent fewer types of pneumococci – for which they had been vaccinated – in their nose and/or throat than children in the unvaccinated group by the age of two years. Reducing nasal carriage of the pneumococcal bacteria in babies prevents its further spread throughout the population.
Pneumococci can cause meningitis, pneumonia and middle ear infection in children. Apart from babies and toddlers, the elderly and people with an immune disorder are particularly vulnerable to becoming ill from a pneumococcal infection. The pneumococcal vaccine has been included in the Netherlands national vaccination programme (RVP) since 2006 and protects people against seven types of pneumococci. At present, all children receive four pneumococcal vaccinations, at the ages of 2, 3, 4, and 11 months. Other vaccinations in the RVP are given at the same time. The babies in this study were all born well before the inclusion date of the pneumococcal vaccine in the RVP.
In the meantime, thirteen countries in Europe have implemented a three-vaccination schedule. In response to the outcomes of this study, Sanders will be arguing in favor of a new vaccination schedule for the Netherlands. “Our results support the implementation of a vaccination schedule for pneumococcal vaccine involving fewer injections.”
The success of the vaccine depends not only on the protection of the young children vaccinated against pneumococcal disease, but also on the protection of unvaccinated people in the general population. This is due to the fact that pneumococcal bacteria occur less frequently in the nose and/or throat of vaccinated children who therefore do not pass the bacteria on to others. Young children very often have pneumococci in their nose and/or throat and are therefore the main source of infection spread of the bacteria in the population.