Result for
Tag: asymptomatic infection
May 17, 2021
Asymptomatic SARS-CoV-2-Infected Children Attending Hospital with Non-COVID-19 Diagnoses, March 2020-February 2021
A surveillance study conducted between March 1, 2020 and February 21, 2021 in the UK found that out of 1,427 pediatric patients admitted to the hospital, 80 (5.6%) tested positive for SARS-CoV-2, of which 52 (65%) had symptoms compatible with COVID-19, 16 (20%) were asymptomatic, and 12 (15%) were “unclear” because of overlapping symptoms between…
May 11, 2021
Asymptomatic Individuals Positive for Anti-SARS-CoV-2 Antibodies Negative on Molecular Swab
Only 1% (n=212) of over 16,000 frontline workers developed detectable anti-SARS-CoV-2 antibodies during screening in Italy from May to June 2020. Among antibody-positive individuals, only one tested positive for SARS-CoV-2 RNA under a protocol that required antibody-positive participants to be given a PCR test. The authors suggest that performing a PCR test on antibody-positive participants…
May 6, 2021
Association Between Vaccination With BNT162b2 and Incidence of Symptomatic and Asymptomatic SARS-CoV-2 Infections Among Health Care Workers
The Pfizer-BioNTech vaccine was associated with a 93% lower incidence of symptomatic SARS-CoV-2 infection and 86% lower incidence of asymptomatic infection more than 7 days after the second dose in a retrospective cohort of healthcare workers (HCWs) in Israel (n=6,710). The median follow-up period was 63 days. While vaccination was associated with older age and…
April 20, 2021
Serological Investigation of Asymptomatic Cases of SARS-CoV-2 Infection Reveals Weak and Declining Antibody Responses
SARS-CoV-2 anti-nucleocapsid IgM antibodies were detected in a small proportion (6%) of asymptomatic food workers (n=508) in Wuhan in April 2020. In a follow-up survey among 21 of seropositive participants, IgM levels had declined by up to 50% in 90% of individuals. In comparison to a cohort of symptomatic patients 2 months after infection, asymptomatic…
April 5, 2021
SARS-CoV-2 Infection Is Asymptomatic in Nearly Half of Adults with Robust Anti-Spike Protein Receptor-Binding Domain Antibody Response
In a study of 4996 participants (aged 18–82 years, 34.5% men) from Greece with plasma antibodies against SARS-CoV-2 nucleocapsid protein between June and November 2020, 49% of seropositive cases (39/79) reported no history of SARS-CoV-2 infection-related clinical symptoms. The majority of SARS-CoV-2 asymptomatic infections were “unsuspected” cases (26/39) who had no known contact with a…
January 25, 2021
Increased Infections, but Not Viral Burden, with a New SARS-CoV-2 Variant
[Pre-print, not peer-reviewed] A large community surveillance study in the UK found evidence for increases in S-gene target failures (SGTF) of SARS-CoV-2, consistent with expansion of the B.1.1.7 variant, at a time in mid-November when non-SGTF strains were stable or declining. Data were analyzed from nose and throat swabs (n=1,553,687) collected from September 28, 2020…
The Proportion of SARS-CoV-2 Infections That Are Asymptomatic
At least one third of SARS-CoV-2 infections were characterized as asymptomatic in a systematic review of cross-sectional and longitudinal observational studies and reports of mass screening for SARS-CoV-2. Most studies (43/61) used PCR testing of nasopharyngeal swabs to detect current infection, and 18 studies used antibody testing to detect current or prior infection. In 14…
January 20, 2021
Follow‐up of SARS‐CoV‐2 Positive Subgroup from the Asymptomatic Novel CORonavirus INfection (ACORN) Study
22% of asymptomatic participants with positive SARS-CoV-2 nasopharyngeal swabs developed symptoms within 14 days, according to results from the Asymptomatic novel CORonavirus iNfection (ACORN). Symptoms developed in 19 out of 86 participants a median of 6 days after the initial positive test result, the most frequently reported of which were fatigue or muscle aches (11%),…
November 9, 2020
The Prevalence of Asymptomatic and Symptomatic COVID19 Disease in a Cohort of Quarantined Subjects
In a cohort of 2,714 travelers returning to Bahrain by air between February 25th and March 14th, 2020, 136 were SARS-CoV-2 positive on arrival, 68% of whom were asymptomatic. A further 52 became SARS-CoV-2 positive during the mandatory 14-day quarantine following arrival, 46% of whom remained asymptomatic until viral clearance. Al-Qahtani et al. (Nov 2,…