Adults 50 years of age and older living in long-term care facilities or community-dwelling are susceptible to respiratory syncytial virus (RSV) infection, although observed incidence and severity were low during the COVID-19 pandemic, according to study findings published in Open Forum Infectious Diseases.
Prospective surveillance studies on the disease burden of RSV in adults are lacking. Investigators therefore evaluated the burden of confirmed RSV-acute respiratory infections (cRSV-ARI) in older adults living in long-term care facilities (LTCF) and in the community, in a study conducted in the US and Europe (ie, Spain, Germany, Estonia, Belgium, and United Kingdom) over 2 RSV seasons spanning from 2019 to 2021.
The researchers conducted a longitudinal prospective cohort study of 1981 participants, who included: (1) medically-stable, community-dwelling European adults at least 50 years of age (mean age 65.1 years; 61.2% women; 72.3% at home without assistance); and (2) adults at least 65 years of age living in long-term care facilities in the US and Europe (mean age 82.7, years; 64.8% women; more than half with 1 or more roommates). The study covered 2 RSV seasons (October 2019/March 2020 and October 2020/June 2021) and sought to identify RSV-ARIs confirmed with reverse-transcriptase polymerase chain reaction (RT-PCR) from combined nasal/throat swabs. An ARI was defined as concomitantly having at least 2 of the following symptoms: new or increasing cough, sore throat, rhinorrhea/nasal congestion, fever, wheezing, shortness of breath or dyspnea, or sputum production.
In season 1, investigators included 1251 community-dwelling adults and 664 adults living in long-term care facilities in analyses. Among community-dwelling adults, the overall incidence rate (IR) for cRSV-ARI was 37.25 cases/1000 person-years (95% CI, 22.62-61.35) (about 2 in every 100 participants) and the attack rate (AR) was 1.84%. Among adults living in long-term care facilities, the incidence rate was 47.85 cases/1000 person-years (95% CI, 22.58-101.40) and the attack rate was 2.26%. Less than one-fifth of participants with cRSV-ARI experienced complications (mostly respiratory), none were hospitalized, and there were no deaths.
In Season 2, investigators included 1223 community-dwelling adults and 494 adults living in long-term care facilities in analyses. For this season, which occurred in the midst of the global COVID-19 pandemic, the researchers found 1 case of cRSV-ARI (IR=2.91; 95% CI, 0.40-20.97; AR=0.20%) without complication, hospitalization, or death.
Although hospitalizations and fatalities were not frequent in this population, the observed disease burden supports the need for prevention strategies against RSV among the older adults.
There were no recurrent RSV-ARI cases reported during the same season. Among all participants with cRSV-ARI, most of those who were community-dwelling (69.6%) were classified as fit and most living in long-term care facilities (69.2%) were classified as frail pre-RSV season 1. Additionally, more than 95% of those with cRSV-ARI presented with concomitant conditions at the start of the season.
A major limitation of the study was that it took place during the COVID-19 pandemic, which undoubtedly affected disease exposure and transmission rates in the study population, especially during season 2. Other limitations include underpowered sample size, potential errors in estimating RSV incidence, lack of generalizability due to the inclusion of only medically stable participants, and selection bias.
“RSV is an important cause of disease burden in [community-dwelling] and [long-term care facility] adults,” investigators concluded. “Although hospitalizations and fatalities were not frequent in this population, the observed disease burden supports the need for prevention strategies against RSV among the older adults,” said study authors.
Disclosure: This research was supported by GlaxoSmithKline Biologicals SA.
Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.