This type of spread was decisive in homes where the presence of the virus on surfaces increased the probability of contracting it by 3.8 times
A study released this Thursday confirms for the first time empirically that the spread of the coronavirus within homes was due to its presence on hands and surfaceswhich, in the face of future pandemics, justifies the need to maintain good hygiene.
The study, conducted by scientists from Imperial College London in collaboration with the UK Health Security Agency (UKHSA) and the University of Oxford, shows that the risk of infection among close friends increased if the virus was present “on people’s hands and surfaces of the home that are often touched.
The research led by Ajit Lalvani, published in “The Lancet Microbe”, did not test for the presence of the virus in the air and therefore it does not rule out that it was also transmitted in this way.
the researchers examined 414 contacts living in the same households as 279 diagnosed cases, between August 1, 2020 and March 31, 2021, at the height of the pandemic and when few people had been vaccinated. The age range was from 6 to 79 years, and 52% were women, they point out.
All “contacts” underwent regular PCR tests for SARS-CoV-2 infection and swabs were also obtained from the hands of both the primary cases and their relatives, as well as from the most frequently handled surfaces, such as door handles. refrigerator doors and kettles or kitchen taps.
The researchers found that “if the virus was detected on the hands of the main cases, contacts in your household were 1.7 more likely to be infected than those in households where the primary cases did not have the virus on their hands.”
If the virus was present on surfaces, contacts were 3.8 times more likely of having the virus on their hands and 1.7 times more likely to test positive in a PCR, they point out.
Nalvani states that “until now it has not been shown that the presence of the virus on people’s hands or on household surfaces allows anticipating transmission to contacts.”
the findings support the adoption of certain measures within the home when someone has an infection, particularly “frequent hand washing, regular surface disinfection and physical distancing, as well as the use of masks to slow the spread of COVID-19,” the study says.
The authors warn that his research is observational only, so he doesn’t prove a “causation”, and further acknowledge that non-white ethnicities and older age groups were overrepresented. On the other hand, due to the dates in which it was developed, the study is limited to the pre-alpha and alpha variants, they point out.