Transmission of the novel coronavirus within households is high, occurs quickly, and can originate from both children and adults, according to a new study which assessed 101 houses in the US. The preliminary findings from the ongoing research, published in the journal Morbidity and Mortality Weekly Report, revealed that 51 per cent of others living with someone who was positive for COVID-19 also became infected.
"We observed that, after a first household member became sick, several infections were rapidly detected in the household," said Carlos G. Grijalva, study co-author and associate professor of Health Policy at Vanderbilt University Medical Center in the US. "Those infections occurred fast, whether the first sick household member was a child or an adult," Grijalva said.
According to the research, at least 75 per cent of the secondary household infections occurred within five days of the first person in the household experiencing symptoms. It also found that less than half of household members experienced symptoms when they first tested positive, and many reported no symptoms throughout the seven-day daily follow-up period.
"In the absence of an efficient approach for identification of infections without regard to symptoms, these findings suggest that prompt adoption of isolation measures as soon as a person feels ill might reduce the probability of household transmission," the scientists wrote in the study. Citing the limitations of the study, the scientists said the initial household member who experienced symptoms was considered the index patient in the research, while other household members may have been infected concurrently but developed symptoms at different times or remained asymptomatic.
However, the researchers believe the findings still underscore the potential for transmission from symptomatic or asymptomatic contact with household members and the importance of quarantine. "Because prompt isolation of persons with COVID-19 can reduce household transmission, persons who suspect that they might have COVID-19 should isolate, stay at home, and use a separate bedroom and bathroom if feasible," the scientists said.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.