Non-PCV7 Pneumococcal Disease Increasing in Spain

By David Douglas

NEW YORK (Reuters Health) Feb 14 - The introduction of 7-valent pneumococcal conjugate vaccine (PCV7) in Spain in 2001 has been followed by the emergence of invasive pneumococcal disease caused by virulent clones of non-PCV7 serotypes.

In the January 15th issue of Clinical Infectious Diseases, Dr. Carmen Munoz-Almagro of the University of Barcelona and colleagues report their study of the incidence of culture-proven invasive pneumococcal disease (IPD) in children admitted to a Barcelona hospital in the pre-vaccine era from 1997 to 2001 and in 2002 to 2004.

Between the two periods there was a 58% increase in IPD in children aged less than 2 years. In children aged 2 to 4 years, the corresponding increase was 135%. At clinical presentation, in children aged less than 5 years, the rate of pneumonia and empyema increased by 320%.

These increases were caused by non-PCV7 serotypes, which accounted for 38% of infecting serotypes in the pre-vaccine era compared to 72% after vaccine introduction.

However, penicillin resistance fell from 48% to 27% over the same period.

Dr. Matthew R. Moore, co-author of an accompanying editorial, told Reuters Health that "we applaud the work of Dr. Munoz-Almagro because it will help Spanish health authorities to evaluate the impact of pneumococcal conjugate vaccine in the future."

Dr. Moore of the Centers for Disease Control and Prevention in Atlanta, Georgia, added that "an important lesson from the pneumococcal conjugate vaccine experience in the U.S. and in other countries is that surveillance for pneumococcal disease is critical to assessing vaccine impact."

"With time and more data from Spain and elsewhere," he concluded, "we will gain a greater understanding of the benefits and limitations of pneumococcal conjugate vaccine use and of the optimal methods for tracking vaccine impact."

Clin Infect Dis 2008;46:174-182.

http://www.medscape.com/viewarticle/570215