Which pneumococcal serogroups cause the most invasive disease: Implications for conjugate vaccine formulation and use, part I

We analyzed >70 recent data sets to compare the serogroups causing invasive pneumococcal disease (IPD) with those represented in conjugate vaccine for mulations. Five to 8 and 10-11 serogroups comprise at least 75% of pneumoco ccal isolates from young children and older children/adults, respectively, in each geographic region. Serogroups in the 7-valent formulation (4, 6, 9, 14, 18, 19, and 23) cause 70%-88% of IPD in young children in the United S tates and Canada, Oceania, Africa, and Europe, and <65% in Latin America an d Asia. Serogroups in the 9-valent formulation (7-valent + 1, 5) cause 80%- 90% of IPD in each region except Asia (66%), Serogroup 1 accounts for >6% o f IPD in each region, including Europe, except the United States and Canada and Oceania, In contrast, several serogroups not found in 7-, 9-, and Ii-v alent conjugate formulations are significant causes of disease in older chi ldren/adults, Nevertheless, each conjugate formulation could prevent a subs tantial IPD burden in each region and age group.