Photo Credit: wildpixel

The following is a summary of “Ongoing Symptoms After Acute SARS-CoV-2 or Influenza Infection in a Case-Ascertained Household Transmission Study: 7 US Sites, 2021–2023,” published in the February 2025 issue of Clinical Infectious Diseases by Bullock et al. 

Researchers conducted a retrospective study to assess the prevalence and risk factors for ongoing symptoms 90 days after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 [SCV2]) or influenza infection. 

They gathered baseline health and sociodemographic data from index cases and the household contacts. Daily respiratory specimens were collected for 10 days after enrollment. A follow-up survey was conducted 90 days post-enrollment to assess ongoing symptoms. 

The results showed that 1,967 participants were analyzed, enrolled between December 2021 and May 2023. The risk of ongoing symptoms did not significantly vary by infection status in SCV2 [SCV2-positive: 15.6%; SCV2-negative: 13.9%; odds ratio (OR): 1.14; 95% CI: 0.7–1.69] or influenza [influenza-positive: 8.8%; influenza-negative: 10.0%; OR: 0.87; 95% CI: 0.45–1.72] households. However, among those with documented infections, participants with SCV2-positive had nearly twice the odds of ongoing symptoms compared to participants with influenza-positive (OR: 1.92; 95% CI: 1.27–2.97). 

Investigators concluded that SCV2 households exhibited a higher prevalence of ongoing symptoms compared to influenza households, with underlying conditions and acute COVID-19-like symptoms increasing risk, while hybrid immunity offered protection. 

Source: academic.oup.com/cid/advance-article-abstract/doi/10.1093/cid/ciaf026/8040968