An explosive outbreak of Streptococcus pneumoniae serotype-8 infection in a highly vaccinated residential care home, England, summer 2012

Abstract

In August 2012, an explosive outbreak of severe lower respiratory tract infection (LRTI) due to Streptococcus pneumoniae serotype-8 occurred in a highly vaccinated elderly institutionalized population in England. Fifteen of 23 residents developed LRTI over 4 days (attack rate 65%); 11 had confirmed S. pneumoniae serotype-8 disease, and two died. Following amoxicillin chemoprophylaxis and pneumococcal polysaccharide vaccine (PPV) re-vaccination no further cases occurred in the following 2 months. No association was found between being an outbreak-associated case and age (P = 0.36), underlying comorbidities [relative risk (RR) 0.84 95% confidence interval (CI) 0.34-2.09], or prior receipt of PPV (RR 1.4, 95% CI 0.60-3.33). However, the median number of years since PPV was significantly higher for cases (n = 15, 10.2 years, range 7.3-17.9 years) than non-cases (n = 8, 7.2 years, range 6.8-12.8 years) (P = 0.045), provided evidence of waning immunity. Alternative vaccination strategies should be considered to prevent future S. pneumoniae outbreaks in institutionalized elderly populations.

Streptococcus pneumoniae outbreaks and implications for transmission and control: a systematic review

“…Twelve studies assessed whether case-patients had ever received either pneumococcal vaccine before the outbreak [ 62 , 66 , 67 , 71 , 73 , 74 , 82 , 88 , 89 , 91 , 93 , 97 ]. Of the studies that provided enough information to calculate vaccination coverage of the source population of cases, two reported 0% coverage [ 66 , 88 ], one reported 7% [ 89 ], and one reported 57% [ 93 ]. At least one vaccine failure was reported for 6 studies [ 71 , 74 , 88 , 91 , 93 , 97 ].…”

“…Of the studies that provided enough information to calculate vaccination coverage of the source population of cases, two reported 0% coverage [ 66 , 88 ], one reported 7% [ 89 ], and one reported 57% [ 93 ]. At least one vaccine failure was reported for 6 studies [ 71 , 74 , 88 , 91 , 93 , 97 ]. Two reports described one case-patient vaccine failure of a vaccine received within five years of the outbreak [ 71 , 74 ].…”

“…Two reports described one case-patient vaccine failure of a vaccine received within five years of the outbreak [ 71 , 74 ]. Two studies reported PPSV VE among older adults; 1.00 (95% CI: 0.30, 1.00) [ 63 ] and − 0.41 (95% CI: -2.33, 0.40) [ 93 ]. The poor VE and the outbreak occurring despite 57% vaccination coverage was partially attributed to “waning immunity” by the authors, since all case-patients received the vaccine more than 7 years prior to the outbreak [ 93 ].…”

A Japanese nationwide survey of 23-valent pneumococcal capsular polysaccharide vaccine (PPSV23) revaccination coverage rate among elderly adults aged 65 and older and physician’s attitude

“…However, one British study did find the length of time after PPSV23 vaccination to be associated with pneumococcal pneumonia incidence in an elderly care home: affected residents developed the disease a median of 10.2 years (range: 7.3-17.9) after their last PPSV23 dose, compared with 7.2 years (range: 6.8-12.8) in unaffected residents. 19 Moreover, both Kawakami et al 14,20 and Ohshima et al 15 reported persistent immunogenicity following PPSV23 vaccination, lasting approximately seven years, but revaccination can induce comparable immunogenicity to the initial dose. Suzuki et al also reported that the efficacy of PPSV23 declines beyond 5 years after primary vaccination.…”

“…It is important to create an awareness of pneumococcal revaccination, because pneumococcal pneumonia incidence and mortality among vaccinated person would be associated with time since the initial dose was administered. 19…”