UMass Chan Medical School Faculty Publications


Longitudinal assessment of diagnostic test performance over the course of acute SARS-CoV-2 infection [preprint]

UMMS Affiliation

Division of Infectious Diseases and Immunology, Department of Medicine; UMass Center for Clinical and Translational Science; Department of Emergency Medicine; Division of Biostatistics and Health Services Research, Department of Population and Quantitative Health Sciences; Division of Cardiovascular Medicine, Department of Medicine

Publication Date


Document Type

Article Preprint


Diagnosis | Immunology and Infectious Disease | Infectious Disease | Microbiology | Public Health | Virus Diseases


What is already known about this topic?:

Diagnostic tests and sample types for SARS-CoV-2 vary in sensitivity across the infection period.

What is added by this report?:

We show that both RTqPCR (from nasal swab and saliva) and the Quidel SARS Sofia FIA rapid antigen tests peak in sensitivity during the period in which live virus can be detected in nasal swabs, but that the sensitivity of RTqPCR tests rises more rapidly in the pre-infectious period. We also use empirical data to estimate the sensitivities of RTqPCR and antigen tests as a function of testing frequency.

What are the implications for public health practice?:

RTqPCR tests will be more effective than rapid antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (provided results reporting is timely). All modalities, including rapid antigen tests, showed > 94% sensitivity to detect infection if used at least twice per week. Regular surveillance/screening using rapid antigen tests 2-3 times per week can be an effective strategy to achieve high sensitivity ( > 95%) for identifying infected individuals.


Infectious Diseases (except HIV/AIDS), COVID-19, testing, SARS-CoV-2 infection

DOI of Published Version



Smith RL, Gibson LL, Martinez PP, Ke R, Mirza A, Conte M, Gallagher N, Conte A, Wang L, Fredrickson R, Edmonson DC, Baughman ME, Chiu KK, Choi H, Jensen TW, Scardina KR, Bradley S, Gloss SL, Reinhart C, Yedetore J, Owens AN, Broach J, Barton B, Lazar P, Henness D, Young T, Dunnett A, Robinson ML, Mostafa HH, Pekosz A, Manabe YC, Heetderks WJ, McManus DD, Brooke CB. Longitudinal assessment of diagnostic test performance over the course of acute SARS-CoV-2 infection. medRxiv [Preprint]. 2021 Mar 22:2021.03.19.21253964. doi: 10.1101/2021.03.19.21253964. PMID: 33791719; PMCID: PMC8010751. Link to article on publisher's site


This article is a preprint. Preprints are preliminary reports of work that have not been certified by peer review.

Full author list omitted for brevity. For the full list of authors, see article.

Related Resources

Now published in Journal of Infectious Diseases, doi:10.1093/infdis/jiab337

Link to preprint in PubMed

Journal/Book/Conference Title

medRxiv : the preprint server for health sciences

PubMed ID