Increased Invasive Pneumococcal Disease, North East England, UK

Abstract

Since April 2014, invasive pneumococcal disease incidence has increased substantially across North East England, United Kingdom, reversing the decline that followed the 2006 introduction of pneumococcal conjugate vaccines. Significant increases occurred in 23-valent polysaccharide vaccine serotypes and nonvaccine serotypes. Trends in other regions and long-term effects of multivalent vaccines require further investigation.

Keywords: England; PCV13 vaccine; Streptococcus pneumoniae; United Kingdom; bacteria; incidence; invasive pneumococcal disease; pneumococcal infections; pneumococcal polysaccharide vaccine; vaccines.

Figure 1

Number and incidence (no. cases/100,000 population) of invasive pneumococcal disease cases by vaccine type serotype subgroups in North East England, by quarter April 2006–March 2016. A) All cases. B) Cases caused by 13-valent pneumococcal conjugate vaccine serotypes. C) Cases caused by 23-valent pneumococcal polysaccharide vaccine serotypes, excluding those also contained in PCV13. D) Cases caused by nonvaccine types. Bars show numbers of cases. Lines indicate incidence: error bars indicate 95% CIs.

Figure 2

Trends in incidence of serotypes causing invasive pneumococcal disease associated with recent significantly increasing incidence in North East England, by quarter, April 2006–March 2016. Panels show trends by individual serotypes: A) serotype 8; B) serotype 9N; C) serotype 12F; D) serotype 15A; E) serotype 23F; F) serotype 35F. Bars show observed numbers of cases; broken lines show the percentage of all serotype group cases (A–C PPV23–13; D–F NVT); solid lines show counts of cases predicted by a negative binomial regression model for April 2013–March 2016. NVT, nonvaccine type serotype cases; PPV23-13, 23–valent pneumococcal polysaccharide vaccine serotype cases excluding those also contained in the 13–valent pneumococcal conjugate vaccine.