Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 6 de 6
Int J Environ Res Public Health ; 19(7)2022 03 24.
Article in English | MEDLINE | ID: covidwho-1847294


This study aimed to elucidate the household secondary attack rate (HSAR) of the Delta variant in comparison to the Alpha variant, and evaluate the risk factors among unvaccinated household contacts of patients with coronavirus disease 2019 (COVID-19). We studied household contacts of index cases of COVID-19 infected with Delta (L452R mutation), Alpha (N501Y mutation), and wild strain from December 2020 through November 2021 in Itako, Japan. The HSARs of the entire household contact, and the contact of index case with Delta variant were calculated and compared across the risk factors. We used a generalized estimating equation regression model for the multivariate analysis. We enrolled 1257 unvaccinated contacts from 580 households. The HSAR was higher in household contacts of index patients with Delta (48.5%) than with Alpha variant (21.7%) (aOR = 3.34, p = 0.000). In Delta variants, the HSAR was higher in household contacts with spousal relationships to index patients (63.4%) than contacts with other relationships (45.5%) (aOR 1.94, p = 0.026), and was lower in household contacts of index patients aged ≤19 (33.1%) than for contacts of index cases aged 20-59 years (52.6%) (aOR = 0.50, p = 0.027). The result of our study can be used to devise informed strategy to prevent transmission within households.

COVID-19 , COVID-19/epidemiology , Humans , Incidence , Japan/epidemiology , SARS-CoV-2/genetics
J Infect Dis ; 222(7): 1098-1102, 2020 09 01.
Article in English | MEDLINE | ID: covidwho-661147


During a COVID-19 outbreak on the Diamond Princess cruise ship we sampled environmental surfaces after passengers and crew vacated cabins. SARS-CoV-2 RNA was detected in 58 of 601 samples (10%) from case cabins 1-17 days after cabins were vacated but not from noncase cabins. There was no difference in detection proportion between cabins of symptomatic (15%, 28/189; cycle quantification [Cq], 29.79-38.86) and asymptomatic cases (21%, 28/131; Cq, 26.21-38.99). No SARS-CoV-2 virus was isolated from any of the samples. Transmission risk of SARS-CoV-2 from symptomatic and asymptomatic patients may be similar and surfaces could be involved in transmission.

Betacoronavirus/isolation & purification , Coronavirus Infections/epidemiology , Disease Outbreaks , Environmental Monitoring , Pneumonia, Viral/epidemiology , RNA, Viral/isolation & purification , Betacoronavirus/genetics , COVID-19 , Coronavirus Infections/transmission , Coronavirus Infections/virology , Humans , Pandemics , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , SARS-CoV-2 , Sampling Studies , Ships , Specimen Handling
Covid-19 SARS-CoV-2 School Reopening novel coronavirus re-open schools ; 2020(Japan Medical Journal)
Article in Japanese | WHO COVID | ID: covidwho-665887
Non-conventional in English | WHO COVID | ID: covidwho-592135