Shorter Incubation Period among COVID-19 Cases with the BA.1 Omicron Variant.
Int J Environ Res Public Health
; 19(10)2022 05 23.
Article
in English
| MEDLINE | ID: covidwho-1903378
ABSTRACT
We aimed to elucidate the range of the incubation period in patients infected with the SARS-CoV-2 Omicron variant in comparison with the Alpha variant. Contact tracing data from three Japanese public health centers (total residents, 1.06 million) collected following the guidelines of the Infectious Diseases Control Law were reviewed for 1589 PCR-confirmed COVID-19 cases diagnosed in January 2022. We identified 77 eligible symptomatic patients for whom the date and setting of transmission were known, in the absence of any other probable routes of transmission. The observed incubation period was 3.03 ± 1.35 days (mean ± SDM). In the log-normal distribution, 5th, 50th and 95th percentile values were 1.3 days (95% CI 1.0-1.6), 2.8 days (2.5-3.1) and 5.8 days (4.8-7.5), significantly shorter than among the 51 patients with the Alpha variant diagnosed in April and May in 2021 (4.94 days ± 2.19, 2.1 days (1.5-2.7), 4.5 days (4.0-5.1) and 9.6 days (7.4-13.0), p < 0.001). As this incubation period, mainly of sublineage BA.1, is even shorter than that in the Delta variant, it is thought to partially explain the variant replacement occurring in late 2021 to early 2022 in many countries.
Keywords
Full text:
Available
Collection:
International databases
Database:
MEDLINE
Main subject:
Infectious Disease Incubation Period
/
SARS-CoV-2
/
COVID-19
Type of study:
Observational study
Topics:
Long Covid
/
Variants
Limits:
Humans
Country/Region as subject:
Asia
Language:
English
Year:
2022
Document Type:
Article
Affiliation country:
Ijerph19106330
Similar
MEDLINE
...
LILACS
LIS