Household transmission of the Delta Covid-19 variant in Queensland, Australia: a case series

Abstract

Household transmission plays a key role in the spread of Covid-19 through populations. In this paper, we collected and analysed retrospective case report data and follow-up interview responses from households with a positive case of the Delta Covid-19 variant in Queensland in 2021. The overall secondary attack rate (SAR) among household contacts was 29.6% and the mean incubation period for secondary cases was 4.3 days. SAR was higher where the index case was male (57.9% vs. 14.3%) or aged ≤12 years (38.7% vs. 17.4%) but similar for adult contacts that were double vaccinated (35.7%) and unvaccinated (33.3%). Most interview participants emphasized the importance of clear, consistent and compassionate health advice as a key priority for managing outbreaks in the home. While vaccination did not appear to affect the risk of transmission to adult subjects, uptake in the sample was ultimately high.

COVID-19 isolation/quarantine rules in home care patients

“…Previous studies reported a poor adherence to self-isolation rules and the need for better information about isolation/quarantine protocols from public health officials [ 7 ]. Home health care workers care for played an important role in supporting patients with confirmed and suspected COVID-19 who remain at home [ 8 , 9 ].…”