Hand washing six to 10 times a day has been linked to a lower risk of seasonal coronavirus, research suggests.
Supportive public health guidelines around measures for the Covid-19 outbreak, regular hand washing may reduce the personal risk of getting an infection, a study not peer-reviewed.
Moderate frequency hand washing was associated with a 36% reduction in the risk of coronavirus infection compared to those who washed their hands zero to five times a day.
For higher intensity handwashing, there was no significant dose-response effect, the researchers say.
Sarah Beale of University College London (UCL) Institute of Health Informatics, and lead author of the study, said, “Since Covid-19 appears to exhibit similar transmission mechanisms as seasonal corona viruses, these findings support clear public health messages surrounding the protective effects of hand washing during the pandemic.
“It is important to emphasize that the frequency of hand washing is only one aspect of hand hygiene.
“We also know that both a longer duration of hand washing and the context of hand washing, for example when returning home or before eating, have been associated with a lower overall risk of influenza or influenza-like illness.
“Good hand hygiene should be practiced at all times, regardless of whether you have symptoms or not.
“This will help protect yourself and prevent the virus from accidentally spreading to others around you.”
The study, published in Wellcome Open Research, is based on data from three consecutive winter cohorts (2006 to 2009) from Flu Watch’s English-language study.
For the study, 1,633 participants provided baseline estimates of hand hygiene behavior and coronavirus infections were identified from nasal swabs.
Almost 80% of the participants were over 16 years old.
At the beginning of each season, participants were asked to estimate how often they had washed their hands the previous day.
The frequency of daily hand washing was then categorized as low, zero to five times a day, moderate, six to 10 times a day, or high, more than ten times a day.
Ellen Fragaszy, UCL Institute of Health Informatics and the London School of Hygiene and Tropical Medicine, said, “Something as simple as washing our hands regularly can help us keep infection rates down and reduce transmission.”
The authors write, “This is the first empirical evidence that regular hand washing can reduce the personal risk of contracting a seasonal coronavirus infection.
“These findings support clear public health reports surrounding the protective effects of hand washing in the context of the current Covid-19 pandemic.”
The study was funded by The Medical Research Council and Wellcome Trust.