As we pass the 1-year mark of the COVID-19 pandemic, scientists are still discovering the specific characteristics of this new disease. Perhaps the most obvious physical impact of COVID-19 is on the lungs, but doctors and researchers have also found links between COVID-19 and various other organs and systems, including the heart, brain, and kidneys. SARS-CoV-2 infection also appears to affect the largest organ of the body — the skin. In a recent study, which appears in the British Journal of Dermatology, a group of researchers teamed up with the British Association of Dermatologists to develop a better understanding of the skin manifestations associated with COVID-19. Stay informed with live updates on the current COVID-19 outbreak and visit our coronavirus hub for more advice on prevention and treatment.
COVID-19 and the skin
Since then, a number of other studies have identified skin changes associated with COVID-19. However, some of these reports only included limited numbers of participants. To date, scientists have not identified the full extent and variety of skin changes related to SARS-CoV-2 infection.
The most recent study investigates the issue in a large sample of participants.
A fresh look
Since May 2020, the app has prompted users to report any SARS-CoV-2 testing and results. A person can also report any symptoms. Additionally, the researchers sent out a survey, which was advertised on social media. This was not targeted at users of the app. It asked for information about when a rash appeared, how long it lasted, and what other symptoms were present.
From this survey, the researchers extracted usable data from 11,544 people. Of this group, 2,328 had provided a photo of their rash and gave permission to share it. The team selected a subset of these photos, which they whittled down to 260 images.
The images were “blindly assessed and independently categorized by four experienced dermatologists.” Among the 260 photographs, 52 were discarded by at least one dermatologist, and 208 images were analyzed.
Rashes linked with SARS-CoV-2 infection
Of the 2,021 app users who tested positive for SARS-CoV-2, 8.8% reported skin- related changes, 6.8% reported body rashes, and 3.1% reported rashes on the hands or feet, which are called acral rashes. The body rashes, they theorize, might be caused by “immunological reactions to the virus,” whereas acral rashes could result from blood clots or damaged blood vessel walls. In the group of untested symptomatic users who reported at least one of the main symptoms of COVID-19, the results were similar, with 8.2% reporting skin changes. From the independent survey of 11,544 participants, the researchers analyzed the timing of skin changes. According to the analysis of survey respondents who had tested positive for SARS-CoV-2 and experienced skin changes, 47% of these changes appeared at the same time as other COVID-19 symptoms. For 35% of the respondents, skin changes developed after other symptoms had started. For 17% of the participants in this group, a rash appeared before other symptoms. And, interestingly, in 21% of participants, a rash was the only symptom.
Using the photos of the participants’ rashes, the scientists identified the most common types, which were:
- papular rashes (41.2%) — small, raised bumps
- urticaria (30%) — red, itchy welts
- acral rashes (23.1%) — lesions on the hands or feet
Acral lesions and papular rashes lasted for an average of 13 or 14 days, respectively, and urticaria for just 5 days. The scientists have added the images to an online database.
It is crucial to note that the participants in this study were predominantly white Europeans. As the researchers acknowledge, “We could not assess whether ethnicity affected the prevalence of cutaneous symptoms, as the number of non‐ European users with skin symptoms was too low.” Recognition of such early signs and symptoms of COVID-19 may enable identification of cases missed when relying only on the core symptoms, allowing preventive measures to be put in place to minimize further spreading of the infection.