The latent period of coronavirus disease 2019 with SARS‐CoV‐2 B.1.617.2 Delta variant of concern in the postvaccination era

Abstract

Introduction Emerging variants of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) have resulted in new challenges for epidemic prevention and control worldwide. However, little is known about the latent period of coronavirus disease by the SARS‐CoV‐2 Delta variant of concern (VOC) in the postvaccination era. Methods The epidemiology and clinical data of cases with confirmed SARS‐CoV‐2 Delta VOC infection were retrospective collected. Dates of the first positive PCR test were collected to estimate the distribution of latent period. Results Of the 40 patients, 16 were male (40%). The median age of patients was 47.5 years. The median latent period of patients was 6.0 days (interquartile range [IQR], 4.0−9.0 days) and the longest latent period was 13.0 days after exposure. The latent periods were longer in male patients compared to female patients (median, 8.5 days vs. 5.0 days, p = .041). The median latent period was comparable among fully vaccinated cases (6.5 days), no vaccinated cases (7.5 days), and partially vaccinated cases (5.5 days). Conclusions The median latent period of SARS‐CoV‐2 Delta VOC infection was 6.0 days. The latent period between vaccinated and non‐vaccinated patients was not significantly different. The 14‐day quarantine program is sufficient to prevent the transmission of COVID‐19 by Delta VOC in the postvaccination era.

Rapid Detection of Predominant SARS-CoV-2 Variants Using Multiplex High-Resolution Melting Analysis

“…HRM is an easy and reliable closed-tube analysis that has been applied for the identification of mutations by scanning or molecular typing in several research fields, such as epidemiology and microbiology. Exploiting the advantages of HRM, our team has used this approach for the detection of several pathogens and their mutation sites, for example, in Neisseria gonorrhoeae , Chlamydia trachomatis , Mycoplasma genitalium , and SARS-CoV-2 ( 16 – 19 ). In these works, we developed a one-step multiplex HRM method for SARS-CoV-2 detection and mutation site identification, consisting of five assays: one assay detected SARS-CoV-2, and the other four assays obtained 12 mutation sites for variant analysis ( 19 ).…”

“…Exploiting the advantages of HRM, our team has used this approach for the detection of several pathogens and their mutation sites, for example, in Neisseria gonorrhoeae , Chlamydia trachomatis , Mycoplasma genitalium , and SARS-CoV-2 ( 16 – 19 ). In these works, we developed a one-step multiplex HRM method for SARS-CoV-2 detection and mutation site identification, consisting of five assays: one assay detected SARS-CoV-2, and the other four assays obtained 12 mutation sites for variant analysis ( 19 ). Moreover, this method proved to be rapid, inexpensive, and flexible, showing high sensitivity and accuracy, and exhibited no cross-reactivity with other respiratory pathogens.…”

A prevalence study of COVID-19 among healthcare workers in a pandemic hospital in the Samsun province of Turkey

“…The average latent period (time period between infection and becoming capable of infecting others) of SARS-CoV-2 infection is 3-6 days, while the average incubation period (time period between infection and the onset of symptoms) is 5-7 days with a range of between 2 and 14 days [14][15][16][17]. Interestingly, data suggests that the serial interval (time from illness onset in the primary case to illness onset in the secondary case), latent and incubation periods are variant dependent, with Omicron, for example, showing a shorter serial interval compared to the ancestral Wuhan strain [18][19][20][21].…”

COVID-19: Using the Right Tools at the Right Time

“…22 While newer variants may be associated with more people developing symptoms and turning positive in the first few days after an exposure there are still individuals not testing positive until near the end of this 14 day period. 23 If a person reaches day 14 and is not testing positive, the likelihood of having acquired an infection has most likely passed. 23 A well described aspect of SARS-CoV-2 is its ability to generate subclinical or asymptomatic infection with transmission despite no obvious symptoms.…”

“…23 If a person reaches day 14 and is not testing positive, the likelihood of having acquired an infection has most likely passed. 23 A well described aspect of SARS-CoV-2 is its ability to generate subclinical or asymptomatic infection with transmission despite no obvious symptoms. [24][25][26] Asymptomatic transmission from patients prior to or without ever progressing through the early clinical phases as was documented in the Diamond Princess Cruise Ship Cohort and in other contract tracing and modeling studies.…”