SARS-CoV-2 rebound and infectious shedding among adults with and without oral antiviral use: a case-ascertained prospective household study

SHAH M; ABEDI GR; LU S; GARCIA-KNIGHT M; PINEDA-RAMIREZ J; GOLDBERG SA; ZHANG A; FORTES-COBBY M; PARK S; MARTINEZ A; SO M; ANGLIN K; TORRES C; PELUSO M; MARTIN J; ANDINO R; MIDGLEY C; KELLY JD; BRIGGS-HAGEN M; PFISTER K

Congreso; IDWeek 2023; 2023

BackgroundOral an virals reduce the risk of severe COVID-19. Viral load and symptom rebound have been reported in people with COVID-19 with and without an viral treatment, and CDC recommended repeat isola on for those with rebound. We aimed to assess the associa on between SARS-CoV-2 rebound and infec ousness.MethodsWe included non-hospitalized adults with COVID-19 during December 31, 2021—March 26, 2023, enrolled in a prospec ve household study in San Francisco (FindCOVID), some of whom received oral an viral treatment. Par cipants underwent daily tes ng by qRT-PCR, an gen tes ng, and viral culture, for 14 days post-symptom onset (PSO), and frequent tes ng therea er through day 28 PSO. We defined rebound as 1) a viral load (VL) increase of >2 log10 copies/mL in both N and E genes, to >3 log10 copies/mL, a er the reference day (defined as the last day of oral an viral treatment or Day 6 PSO for untreated adults) or 2) an an gen posi ve test post-reference day, with ≥2 preceding nega ve tests. For adults with rebound, we also assessed for new culture posi vity post-reference day.ResultsAmong 79 adults with symptoma c COVID-19, 25 (32%) were treated with an oral an viral (24 with nirmatrelvir-ritonavir, 1 with molnupiravir) (Table 1); 39 of 55 untreated par cipants were eligible for treatment based on age or comorbidi es. We observed no differences in dura on of RNA, an gen, or culture posi vity PSO between treated and untreated adults (p>0.05, Table 1). Rebound was detected in 11/79 (13.9%) adults, including 7/24 (29%) treated, 3/38 (8%) untreated but eligible, and 1/17 (6%) untreated and ineligible; all 11 adults with rebound had VL rebound and 5 also had an gen rebound (Table 2, Figure 1). Among 11 adults with rebound, 3 had new posi ve cultures, occurring on days 12-14, 10-12, 12, and 9-10 PSO (Figure 1); all 4 were treated and 3 also had an gen rebound.ConclusionWe detected VL or an gen rebound in adults treated or not treated with oral an virals. New culture posi vity was only detected in treated adults with rebound. Oral an virals for COVID-19 should be used to prevent severe disease, but detec on of culturable virus beyond 10 days PSO supports guidance to reisolate during COVID-19 rebound.