Early in the pandemic there were reports that itchy rashes such as hives and chilblains could be potential symptoms of COVID-19. But these early reports were mostly among people hospitalised with COVID-19.

This study looks at data from around 336,000 UK adults who registered to use a symptom-tracking app.  A subsample of 27,000 received a swab to see if they were carrying the COVID-19 virus. About 9% of those who tested positive had a skin rash. Among app users who remained untested, about 8% of those reported classic COVID symptoms of fever and cough also reported a skin rash.  The most common types of rashes linked to COVID-19 were hives (urticaria), itchy red bumps (papular rash) or chilblain-like rashes on hands or feet.

The findings seem to confirm skin rashes as another potential symptom of COVID-19. But as dermatologists advise skin rashes are extremely common so their presence alone does not automatically mean that person as COVID-19.

Where did the story come from?

Several news sites reported the study in response to a press release issued by Kings College London, who conducted the study. The research paper is available in preprint form and has not been peer-reviewed.

What is the basis for the claim?

The research paper used data from the COVID-19 Symptom Study app. A total of 336,847 UK adults registered with this app in May and June 2020.

  • 1% of this sample (27,157) had a swab test to see if they were carrying the virus, 7.4% of whom (2,021) tested positive
  • 8% of those who tested positive (178) had skin rashes
  • 9% of people who tested negative (1497) had skin rashes

The researchers calculated that of people who were tested, those with a rash had a 67% higher chance of testing positive than those without a rash.

Nearly 60,000 app users who didn’t receive a swab test also reported the presence of any symptoms. Eight percent of those who reported ‘classic’ symptoms of COVID-19 such as cough, fever and loss of sense of smell reported a skin rash as well.

In a second part to the study, the researchers looked at an online survey of 11,546 people with skin rashes possibly linked to COVID-19. Six percent of these people had a positive viral or antibody test for COVID-19. Around 1 in 5 of them reported skin symptoms as the first or only symptom, while the majority said symptoms occurred alongside or after other symptoms.

A dermatologist assessed a random sample of 365 photographs from the full group (including those untested). They considered that 14% were either too unclear to identify or unlikely to be linked to COVID-19. The remainder were one of the three types; 28% urticarial (hives), 41% papular (raised lumps) and 23% had rashes on the hand, feet or face.

What do trusted sources say?

At present, skin rashes are not included in the UK National Health Service or US Centers for Disease Control and Prevention lists of potential symptoms for COVID-19. However, the World Health Organisation includes them as ‘less common symptoms’.

The British Association of Dermatology says on its website: “skin lesions and rashes are common, and on their own should not necessarily be a cause for concern.” It adds: “Members of the public should be very cautious about trying to self-diagnose COVID-19 based on skin symptoms; rashes and other skin lesions are common and hard to differentiate between without expertise.”

Analysis by EIU Healthcare, supported by Reckitt Benckiser

Citation

  1. Veronique Bataille et al. Diagnostic value of skin manifestation of SARS-CoV-2 infection (2020) medRxiv doi: 10.1101/2020.07.10.20150656 https://www.medrxiv.org/content/10.1101/2020.07.10.20150656v1.full.pdf (Accessed 24 July 2020).

 

Reading list

  1. British Association of Dermatology. Five common skin manifestations of COVID-19 identified. April 2020. https://www.skinhealthinfo.org.uk/five-common-skin-manifestations-of-covid-19-identified/ (Accessed 24 July 2020).