Decreased Pneumococcal Carriage Among Older Adults in Denmark During the COVID-19 Lockdown

Abstract

Background COVID-19 containment measures reduced the burden of invasive pneumococcal disease. Data on pneumococcal carriage rates among adults during the pandemic are scarce. Methods Naso- and oropharyngeal swabs and questionnaires were collected during January 2019 to December 2021 from adults 64+ years of age without concurrent infectious disease. Carriage was determined lytA/piaB targeted PCR. Results A total of 1556 participants provided paired naso- and oropharyngeal swabs. The median age of participants was 74 (IQR 70-79) years and 54% were female. Streptococcus pneumoniae DNA was detected in 146 (9.4%) oropharyngeal and 34 (2.2%) nasopharyngeal swabs. The carriage rate decreased from 12.9% (95% CI 10.1-16.1, n=66/511) pre-lockdown (January 2019 – February 2020) to 4.2% (95% CI 2.0-7.5, n=10/240) during lockdown (March 2020 – February 2021) and increased to 12.1% (95% CI 9.8-14.7, n=87/719) with the re-opening of society (March 2021- December 2021) (P=0.0009). Conclusion Pneumococcal carriage prevalence declined significantly during pandemic mitigation measures and rebounded to pre-pandemic levels as mitigation measures were lifted. Pandemic containment measures may effectively reduce pneumococcal carriage among older adults.

Contact with young children is a major risk factor for pneumococcal colonization in older adults

“…37,38 In contrast to our findings, carriage among older adults in Denmark was reported to decline. 39 Interestingly, it was also reported that in Denmark, distancing recommendations, including the distancing from children, were strictly adhered to, 40 unlike in our population. 6 A limitation of our study; however, was that despite enrolling from a diverse population, or study participants were skewed towards white individuals with higher education, meaning that results may not be representative across the entire greater New Haven community.…”

Revealing the drivers of antibiotic resistance trends inStreptococcus pneumoniaeamidst the 2020 COVID-19 pandemic: Insights from mathematical modeling

“…Next, we used the pandemic scenario S19 that best explains the reported trends to test the model using different parameter combinations to mimic different subpopulations (children and the elderly) considering that SARS-CoV-2 infection risk, pneumococcal disease risk, disease severity, bacterial carriage prevalence, and antibiotic prescribing are all highly heterogeneous across age groups. Using scenario S19, we initialized the model with lower and higher baseline carriage prevalence (10%, 20%, and 30%) (Cohen et al, 2023; Rose et al, 2021; Rybak et al, 2022; Tinggaard et al, 2023; Wang et al, 2017), we varied durations of pneumococcal carriage (20, 30, and 45 days), pneumococcal invasion rate, and considered reductions of antibiotic consumption at various levels (-13%, -18%, and -39%) consistent with the French data along with a range of community azithromycin use in COVID-19 infected (0-20%). For a full list of parameters see Appendix 2 – Table 2.…”

“…Yet, surprisingly, a growing number of studies have reported mostly stable pneumococcal carriage throughout the COVID-19 pandemic containment, including among infants in Belgium (Willen et al, 2022), children in Vietnam (Nation et al, 2023), Serbia (Petrović et al, 2022), France (Rybak et al, 2022), South Africa (Olwagen et al, 2023), and Israel (Dagan et al, 2023), adults in Connecticut (Wyllie et al, 2023), and households in Seattle (Bennett et al, 2023). In contrast, a study conducted in Denmark reported a decrease in pneumococcal carriage among older adults during the COVID-19 lockdown (Tinggaard et al, 2023).…”