Estimating the risk of invasive group A Streptococcus infection in care home residents in England, 2009–2010

Abstract

Invasive group A streptococcal (iGAS) infections cause severe disease and death, especially in residents of long-term care facilities (LTCFs). In order to inform iGAS prevention, we compared the risk of iGAS in LTCF residents and community residents. We identified LTCF residents among cases of iGAS from national surveillance (2009-2010) using postcode matching, and cases of hospital-acquired infections via hospital admission records. We used Poisson regression to calculate incidence rate ratios (IRR) and logistic regression to explore factors associated with case fatality rate (CFR). A total of 2741 laboratory-confirmed iGAS cases were matched to a hospital admission: 156 (6%) were defined as hospital-acquired. Out of the total cases, 96 (3·5%) were LTCF residents. Compared with community residents, LTCF residents over 75 years of age had a higher risk of iGAS infection (IRR = 1·7; 95% CI 1·3-2·1) and CFR (OR = 2·3; 95% CI 1·3-3·8). Amongst community-acquired cases, the risk of iGAS in LTCF residents between 75 and 84 years of age doubled (IRR = 2·7; 95% CI 1·8-3·9) compared with their community counterparts. The CFR among community-acquired cases was higher in LTCF residents than community residents (21% vs. 11%). Age remained associated with death in our final model. Our study showed that, even controlling for age, LTCF residents have a higher risk of acquiring and dying from iGAS. Whilst existing co-morbidities may explain this, it is reasonable to assume that the institutional setting may facilitate transmission. Therefore, cases in LTCF require prompt investigation together with a better understanding of factors contributing to the acquisition of infection.

Increased Risk for Invasive Group AStreptococcusDisease for Household Contacts of Scarlet Fever Cases, England, 2011–2016

“…We did not adjust for residence in a long-term care facility or hospitalization in the background risk calculation: 3.5% of iGAS cases in England (2009–2010) were estimated to be acquired in long-term care facilities, and 6% of these infections were estimated to be acquired in hospitals. Residents of long-term care facilities had a 6-fold higher risk for iGAS infection than community residents ( 31 , 32 ). Including institutionally acquired infections slightly increased the background iGAS risk in this study.…”

A Review of Streptococcus pyogenes: Public Health Risk Factors, Prevention and Control

“…Group A streptococcus (GAS) diseases were reported to be common in developing countries [17][18][19] and among the indigenous populations in developed countries [10,15,[20][21][22][23][24][25][26][27][28][29], and reported to be endemic in low socioeconomic communities [9,20,30]. GAS diseases are also present in high socioeconomic communities, in conditions where people are in close proximity to one another for extended periods of time (for example, schools and care facilities) [8,[36][37][38][42][43][44][45][46][47][48].…”

“…The population groups at most risk of being infected with GAS diseases included people with underlying medical conditions [10,17,27,[59][60][61][62], children (0 to 15 years) [8,11,36,[51][52][53][54][55][56] and the elderly [10,43,57,58]. Additionally, pregnant and postpartum women were also identified as groups at risk for GAS diseases [39,41,[63][64][65][66][67][68][69].…”

Invasive group A streptococcal infection outbreaks of type emm118 in a long-term care facility, and of type emm74 in the homeless population, Montréal, Quebec

“…Due to a combination of host- and environment-related factors, elderly people in a long-term care environment are at higher risk of contracting and dying from iGAS (10,11). Several iGAS outbreaks, occurring mostly over periods of a few months, have been reported in this type of setting within Canada and elsewhere in the world (3,12–15).…”