Carriage burden, multiple colonization and antibiotic pressure promote emergence of resistant vaccine escape pneumococci.
Pneumococcal conjugate vaccines target the limited subset of the more than 90 known serotypes of Streptococcus pneumoniae responsible for the greatest burden of pneumococcal disease and antibiotic resistance. Following the introduction of these vaccines, serotypes not targeted were able to expand and resistance became more common within these types. Here we use a stochastic dynamic model of pediatric pneumococcal carriage to evaluate potential influences on the emergence of new resistant lineages following the introduction of a vaccine targeting more common resistant types. Antibiotic pressure was the strongest driver, with no emergence at low levels and universal emergence at high levels. At intermediate levels of antibiotic pressure, higher carriage burden and a greater degree of dual carriage promoted emergence. This may have implications for current plans to introduce childhood pneumococcal vaccination in several high-burden countries.
Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
Patrick K
PK
Mitchell
Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
Marc
M
Lipsitch
Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA whanage@hsph.harvard.edu.
William P
WP
Hanage
D058491:Bacterial Load / Q000187:drug effects*; D001428:Bacterial Vaccines / Q000494:pharmacology*; D002648:Child; D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D011008:Pneumococcal Infections / Q000517:prevention & control*; D013045:Species Specificity; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000235:genetics*
D001428:Bacterial Vaccines
Streptococcus pneumoniae; emergence; model; resistance; vaccination