UCL News


Time spent in busy public places could double risk of contracting COVID-19

5 May 2020

Using public transport, shopping, dining out, going to a party or place of worship and spending time with someone who has a cold are all associated with significantly higher risks of contracting a respiratory illness such as COVID-19, according to new UCL research.


The peer-reviewed Wellcome funded study, used data from the England and Wales Flu Watch cohort and is the first to investigate the impact of specific public activities on the risk of acquiring respiratory tract infection in a population-based cohort.

The UCL research team found being around someone with a cold from outside your household doubled a person’s risk of contracting a respiratory illness and social activities, particularly travelling on crowded busses or underground trains and shopping also carried the highest risks (when social-distancing measures were not in place).

Professor Andrew Hayward (UCL Centre for Inclusive Health) said, “This research clearly shows that respiratory infections such as COVID-19 can spread easily in a wide range of public spaces including on public transport, in shops and restaurants and at places of worship and parties.

“As we start to come out of lockdown, these findings support continuing intensive social distancing and isolation measures to reduce community transmission of COVID-19. It is particularly important that those with symptoms stay at home and that people continue to avoid crowded public spaces as lockdown is lifted. This is also particularly important for the elderly and those with chronic illness."

The Flu Watch cohort was a community study of respiratory infection occurrence and risk factors which followed households across England and Wales through the winter seasons of 2006/7-2010/11.

626 participants who provided self-reported data on respiratory infections on a weekly basis throughout autumn until spring were involved in the analysis.

Illness diaries included a series of questions on how many days in the week before illness onset a series of activities (such as using public transport, shopping, eating out or going to the cinema or a party or being with someone with a cold outside their house) had occurred.

The same questions were asked at baseline and in total 1005 respiratory illnesses were reported. The researchers measured exposures in the week before illness to focus on the likely incubation period of common respiratory infections. By comparing exposures prior to periods of illness and at baseline in the same individuals they were able to ensure that the results were not biased by differences between individuals.

Spending more than five minutes in the same room as someone with a cold travelling on public transport, shopping, eating out or going to a party or place of worship were more common in the week before illness than the baseline week.

This work was supported by the Wellcome through funding to The Flu Watch study. The Flu Watch study also received funding from the Medical Research Council (MRC).

Professor Hayward is also leading UCL's Virus-Watch study, an initiative that forms part of the £24.6 million rapid research response funded by UK Research and Innovation (UKRI), and by the Department of Health and Social Care through the National Institute for Health Research (NIHR).  

The study to set to recruit 25,000 individuals and collect data between April 2020 to March 2021 to investigate the extent of the spread of coronavirus within communities and how social distancing affects the risk of infection.



Credit:  London/9091 images  Source: Pixabay CC 2.0

Media contact

Rowan Walker

Tel: +44 (0)20 3108 8515

Email: rowan.walker [at] ucl.ac.uk