KEY POINTS

  • Hand hygiene can mitigate the spread of COVID-19
  • But empirical evidence has been very limited
  • New study: Handwashing 6-10 times per day can help reduce coronavirus infections

Handwashing in moderate frequency around six to ten times per day is associated with a lower risk of seasonal coronavirus infections, claims a new study.

The experts at the University College London have published their research in Wellcome Open Research and are awaiting peer review. This is by far the first empirical evidence that regular handwashing can lower the personal risk of acquiring seasonal coronavirus infections.

The study was not specifically about the SARS-Cov-2 which causes COVID-19 but it used data from three successive winter cohorts (2006-2009) of the England-wide Flu Watch study. By far, seven coronaviruses have been known to infect human beings and four of them cause common respiratory infections that are sharply seasonal and appear to spread in a similar manner to influenza. 

"Given that COVID-19 appears to demonstrate similar transmission mechanisms to seasonal coronaviruses, these findings support clear public health messaging around the protective effects of handwashing during the pandemic," Sarah Beale (UCL Institute of Health Informatics), Ph.D. researcher and first author on the study told MedicalXpress.

The researchers emphasized that it is important to highlight that frequency of handwashing is just one aspect of following hand hygiene. Both longer duration and when you do it is very important in lowering the risk of infections.

Good hand hygiene practices should be followed at all times, whether or not one exhibits symptoms of infections caused by coronaviruses. “This will help protect yourself and prevent unwittingly spreading the virus to others around you,” Beale told MedicalXpress.

The study:

The researchers included 1,633 individuals who provided baseline estimates of hand hygiene behavior. They then looked for coronavirus infections using nasal swabs.

To assess the participants’ overall handwashing frequency, each of them was asked to estimate the number of times they washed their hands the previous day.

They categorized the frequency of daily handwashing as:

  • Low (≤5 times daily)
  • Moderate (6-10 times daily)
  • High (>10 times daily)

The findings revealed that moderate-frequency handwashing on a daily basis significantly reduces the overall risk of contracting coronavirus. They observed a 36% reduction in the risk of infection compared to those who washed their hands less than 5 times per day.

“Our findings represent important empirical evidence of the value of handwashing, supporting public communication about the importance of this behavior. Hand washing is minimally disruptive and socially acceptable in a variety of community settings and has an important role in raising awareness and slowing transmission alongside measures such as physical and social distancing," concluded the researchers in their paper.