According to a study published in the journal The Lancet Microbe, most transmission of SARS-CoV-2 occurs in households. In the study, the virus was detected on surfaces and the hands of participants, which indicated that the infection was transmitted on contact. Also, the rate of transmission was found to be significantly higher.

Although CoVid is mostly known to spread by aerosols, this study, headed by a researcher of Indian descent, offers the first empirical proof that SARS-CoV-2 contamination of hands and domestic surfaces also plays a significant role in the spread of the infectious disease.

For the prospective study, the team recruited 414 susceptible households living in the same households along with 279 households with newly diagnosed primary cases in London between August 1, 2020, and March 31, 2021, during the Alpha and pre-Alpha waves.

The findings of the study showed that a virus was detected on the hands of the primary cases. They also observed that contact in households with primary cases led to a 1.7-fold increased risk of infection than in households where primary cases did not have the virus on their hands.

Similarly, contacts in the household who had the virus on their hands had a three times higher chance of getting a positive hand swab, and contacts who had the virus on their hands had a twofold increased chance of contracting COVID-19. Contacts were 3.8 times more likely to have detectable virus on their hands and 1.7 times more likely to be infected or have a PCR-positive URT-swab if the virus was present on frequently touched surfaces in the home.

Six of the contacts who were initially uninfected but contracted COVID-19 throughout the trial had positive hand or domestic surface swabs before contracting the illness. According to the researchers, this confirms the hypothesis that the direction of transmission is from contacts hands and household surfaces to their nose and throat. 

(Source: https://www.news18.com/buzz/study-shows-how-peoples-hands-household-surfaces-aid-in-covid-spread-7487029.html )