Invasive disease caused simultaneously by dual serotypes of Streptococcus pneumoniae.

5 years ago

Invasive disease caused simultaneously by dual serotypes of Streptococcus pneumoniae.

Kedibone Ndlangisa, Keith P Klugman, Mushal Allam, Mignon du Plessis, Cheryl Cohen, Rebecca A Gladstone, Nicole Wolter, Anne von Gottberg, Linda de Gouveia

There are at least 98 known pneumococcal serotypes. Invasive pneumococcal (IPD) disease is usually caused by a single serotype, and dual serotype IPD is rare. To assess factors associated with dual serotype IPD, patient information obtained through laboratory-based surveillance for IPD from 2005 through 2014 in South Africa was reviewed. Genomes of isolate pairs from co-infected individuals were sequenced to determine their molecular characteristics. For 30 (91%) of 33 patients with dual serotypes, one or both isolates were a pneumococcal conjugate vaccine (PCV13) serotype. Dual serotype IPD was associated with children <5 years of age [adjusted odds ratio (aOR), 4.7, 95% confidence interval (95% CI), 1.8-11.7], underlying illness (other than HIV) (aOR, 2.8; 95% CI, 1.1-6.6) and death (aOR, 2.5; 95% CI, 1.08-6.09). For each co-infecting pair, isolates were genotypically unrelated and their genotypes were common among isolates of the same serotype in South Africa. Of 701 accessory genes identified among dual serotype IPD isolates, four were common between isolate pairs. Co-infecting isolate pairs had different genotypic backgrounds. The association of dual serotypes with death warrants increased awareness of IPD co-infection caused by two or more serotypes.

Publisher URL: http://doi.org/10.1128/JCM.01149-17

DOI: 10.1128/JCM.01149-17