Personal characteristics and transmission dynamics associated with Sars-CoV-2 semi-quantitative PCR test results
An observational study from Belgium, 2021–2022
Bibliographic Data
| ID | 22087782 |
|---|---|
| Authors | Toon Braeye (0000-0002-5637-4613, Sciensano (Belgium), corresponding author), Kristiaan Proesmans (0000-0002-7787-9397, Ghent University), Dieter Van Cauteren (0000-0001-7470-4834, Sciensano (Belgium)), Ruben Brondeel (0000-0002-9876-4150, Sciensano (Belgium)), Niel Hens (0000-0003-1881-0637, University of Antwerp), Elias Vermeiren (0009-0006-6865-6251, Sciensano (Belgium)), Naïma Hammami (0000-0002-2572-6540, Flemish Community), Ángel Rosas-Aguirre (0000-0002-3271-7028, Grand Charleroi Hospital), Angel Rosas, Adrae Taame (Médecins du Monde), Emmanuel André (0000-0001-8321-3770, KU Leuven), Lize Cuypers (0000-0002-9433-8752, KU Leuven) |
| Year | 2024 |
| Volume | 12 |
| Pages | 1429021-1429021 |
| Publication date | 2024-09-10 |
| Open Access | Yes |
| Type | ARTICLE |
| Venue | Frontiers in Public Health (JOURNAL) |
| Journal identifiers | ISSN: 2296-2565 • E-ISSN: 2296-2565 |
| Publisher | Frontiers Media SA (PUBLISHER • CH) |
| DOI | 10.3389/fpubh.2024.1429021 |
| PMID | 39319296 |
| OpenAlex | W4402422903 |
| Language | EN |
| References cited | 46 |
Introduction Following harmonization efforts by the Belgian National Reference Center for SARS-CoV-2, semi-quantitative PCR test (SQ-PCR) results, used as a proxy for viral load, were routinely collected after performing RT-qPCR tests. Methods We investigated both the personal characteristics associated with SQ-PCR results and the transmission dynamics involving these results. We used person-level laboratory test data and contact tracing data collected in Belgium from March 2021 to February 2022. Personal characteristics (age, sex, vaccination, and laboratory-confirmed prior infection) and disease stage by date of symptom onset were analyzed in relation to SQ-PCR results using logistic regression. Vaccine effectiveness (VE) against a high viral load (≥10 7 copies/mL) was estimated from the adjusted probabilities. Contact tracing involves the mandatory testing of high-risk exposure contacts (HREC) after contact with an index case. Odds ratios for test positivity and high viral load in HREC were calculated based on the SQ-PCR result of the index case using logistic regression models adjusted for age, sex, immunity status (vaccination, laboratory-confirmed prior infection), variant (Alpha, Delta, Omicron), calendar time, and contact tracing covariates. Results We included 909,157 SQ-PCR results of COVID-19 cases, 379,640 PCR results from index cases, and 72,052 SQ-PCR results of HREC. High viral load was observed more frequently among recent cases, symptomatic cases, cases over 25 years of age, and those not recently vaccinated (>90 days). The vaccine effectiveness (VE) of the primary schedule in the first 30 days after vaccination was estimated at 47.3% (95%CI 40.8–53.2) during the Delta variant period. A high viral load in index cases was associated with an increased test positivity in HREC (OR 2.7, 95%CI 2.62–2.79) and, among those testing positive, an increased likelihood of a high viral load (OR 2.84, 95%CI 2.53–3.19)
2019-20 coronavirus outbreak · Biology · Disease · Observational study · Outbreak · Pcr test · Polymerase chain reaction · Sars virus · Telecommunications · Computer Science · COVID-19 epidemiological studies · Medicine · SARS-CoV-2 and COVID-19 Research · SARS-CoV-2 detection and testing · Genetics · Internal Medicine · Virology
| Highly cited | No |
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