Well over two years into the pandemic, hundreds of thousands of COVID cases continue to be recorded around the world every day.
But what about some of the more obscure signs and symptoms? From skin lesions to hearing loss, emerging data is increasingly showing us that COVID symptoms can go beyond what you might expect from a regular cold or a flu.
1. Skin lesions
COVID-related skin complaints are not uncommon. In fact, a U.K. study published in 2021 found that one in five patients only exhibited a rash and no other symptom.
COVID can affect the skin in a variety of ways. Some people may experience a widespread maculopapular rash (flat or raised areas of discolored skin), while others might present with hives (raised areas of itchy skin).
“COVID toes,” meanwhile, describes red, swollen or blistering skin lesions on the toes. This symptom is more commonly seen in adolescents or young adults with mild or no symptoms.
Most COVID skin lesions tend to go away after a few days, or in some instances a few weeks, without the need for any specialized treatment. If the skin is very itchy or painful though, you can consult a GP or dermatologist, who may recommend treatment such as a cream.
2. COVID nails
During an infection, including that of SARS-CoV-2 (the virus which causes COVID-19), our bodies naturally try to express that they’re under an unusual amount of stress. They can do this in a variety of weird and wonderful ways, including through our nails. “COVID nails” encompasses changes such as:
- Beau’s lines—horizontal indentations that occur at the base of the fingernails or toenails when there’s a temporary interruption in nail growth due to a physical stress on the body
- Mees’ lines—horizontal white lines that appear on the nails, thought to be caused by the abnormal production of proteins in the nail bed
- a red half-moon pattern which develops at the base of the fingernails (the mechanism underlying this change is unclear).
The data on how many people experience COVID nails is limited, but it’s been estimated it could be up to 1–2% of COVID patients.
COVID nails tend to appear in the days or weeks following COVID infection as the nails grow. Although they might be painful initially, the vast majority tend to return to normal over a few weeks.
Notably, while these changes may be indicative of COVID, they can also be caused by different things. For example, Beau’s lines can be secondary to chemotherapy or another infection.
3. Hair loss
Hair loss is perhaps an understated symptom of COVID-19, usually occurring one month or more after the acute infection. In one study of almost 6,000 people who had previously had COVID, hair loss was the most common post-COVID symptom, reported by 48% of participants. It was especially prevalent among people who had severe COVID and white women.
It is thought that this results from the hair “sensing” the stress in the body, leading to excess shedding. Indeed, hair loss can also be triggered by other stressful events, such as childbirth. The good news is that with time the hair grows back to normal.
4. Hearing loss and tinnitus
As with other viral infections, such as the flu and measles, COVID has been found to affect the cells in the inner ear, with hearing loss or tinnitus (a constant ringing sensation in the ear) sometimes following infection.
In a review study that included 560 participants, hearing loss occurred in 3.1% of patients with COVID, while tinnitus occurred in 4.5%.
In one study of 30 people who had been diagnosed with COVID, and 30 who hadn’t—none with pre-existing hearing problems—the researchers found that COVID was associated with damage to the inner ear which led to hearing impairment at higher frequencies. While for the vast majority of patients this resolves on its own, cases of permanent hearing loss linked to COVID have been reported.
Why all these symptoms?
We don’t understand exactly what causes these symptoms, but we know the most important part is played by a process called inflammation. Inflammation is our body’s natural defense mechanism against pathogens; SARS-CoV-2 in this case. It involves the production of “cytokines”—proteins which are important in controlling the activity of immune cells.
Excessive production of these proteins, as a part of the inflammation triggered by COVID infection, can cause sensory deficits, which potentially explain why some people are presenting with hearing loss and tinnitus. It can also disrupt the capillary networks, very tiny blood vessels which provide blood to organs including the ears, skin and nails.
The symptoms we’ve described here are not exclusive to COVID infection. That said, if you notice any of these symptoms, it would be appropriate to consider a COVID test, especially if you’re in an area where COVID is circulating.
You can also contact your GP, particularly if the symptoms are getting worse or causing you significant discomfort. At the same time, you can be reassured that most of these symptoms are likely to improve with time.
News
Nanoparticle-Based Combination Therapy for Resistant Melanoma
A recent study published in Small addresses the persistent difficulty of treating refractory melanoma, an aggressive form of skin cancer that often does not respond to existing therapies. Although diagnostic tools and immunotherapies have improved in [...]
Our DNA May Evolve Much Faster Than Previously Thought
Rapidly mutating DNA regions were mapped using a multi-generational family and advanced sequencing tools. Understanding how human DNA changes over generations is crucial for estimating genetic disease risks and tracing our evolutionary history. However, some of [...]
AI therapy may help with mental health, but innovation should never outpace ethics
Mental health services around the world are stretched thinner than ever. Long wait times, barriers to accessing care and rising rates of depression and anxiety have made it harder for people to get timely help. As a result, governments and health care providers are [...]
Global life expectancy plunges as WHO warns of deepening health crisis Post-COVID
The World Health Organization (WHO) has sounded the alarm on the long-term health repercussions of the COVID-19 pandemic in its newly released World Health Statistics Report 2025. The report reveals a staggering decline in global [...]
Researchers map brain networks involved in word retrieval
How are we able to recall a word we want to say? This basic ability, called word retrieval, is often compromised in patients with brain damage. Interestingly, many patients who can name words they [...]
Melting Ice Is Changing the Color of the Ocean – Scientists Are Alarmed
Melting sea ice changes not only how much light enters the ocean, but also its color, disrupting marine photosynthesis and altering Arctic ecosystems in subtle but profound ways. As global warming causes sea ice in the [...]
Your Washing Machine Might Be Helping Antibiotic-Resistant Bacteria Spread
A new study reveals that biofilms in washing machines may contain potential pathogens and antibiotic resistance genes, posing possible risks for laundering healthcare workers’ uniforms at home. Washing healthcare uniforms at home could be [...]
Scientists Discover Hidden Cause of Alzheimer’s Hiding in Plain Sight
Researchers found the PHGDH gene directly causes Alzheimer’s and discovered a drug-like molecule, NCT-503, that may help treat the disease early by targeting the gene’s hidden function. A recent study has revealed that a gene previously [...]
How Brain Cells Talk: Inside the Complex Language of the Human Mind
Introduction The human brain contains nearly 86 billion neurons, constantly exchanging messages like an immense social media network, but neurons do not work alone – glial cells, neurotransmitters, receptors, and other molecules form a vast [...]
Oxford study reveals how COVID-19 vaccines prevent severe illness
A landmark study by scientists at the University of Oxford, has unveiled crucial insights into the way that COVID-19 vaccines mitigate severe illness in those who have been vaccinated. Despite the global success of [...]
Annual blood test could detect cancer earlier and save lives
A single blood test, designed to pick up chemical signals indicative of the presence of many different types of cancer, could potentially thwart progression to advanced disease while the malignancy is still at an early [...]
How the FDA opens the door to risky chemicals in America’s food supply
Lining the shelves of American supermarkets are food products with chemicals linked to health concerns. To a great extent, the FDA allows food companies to determine for themselves whether their ingredients and additives are [...]
Superbug crisis could get worse, killing nearly 40 million people by 2050
The number of lives lost around the world due to infections that are resistant to the medications intended to treat them could increase nearly 70% by 2050, a new study projects, further showing the [...]
How Can Nanomaterials Be Programmed for Different Applications?
Nanomaterials are no longer just small—they are becoming smart. Across fields like medicine, electronics, energy, and materials science, researchers are now programming nanomaterials to behave in intentional, responsive ways. These advanced materials are designed [...]
Microplastics Are Invading Our Arteries, and It Could Be Increasing Your Risk of Stroke
Higher levels of micronanoplastics were found in carotid artery plaque, especially in people with stroke symptoms, suggesting a potential new risk factor. People with plaque buildup in the arteries of their neck have been [...]
Gene-editing therapy shows early success in fighting advanced gastrointestinal cancers
Researchers at the University of Minnesota have completed a first-in-human clinical trial testing a CRISPR/Cas9 gene-editing technique to help the immune system fight advanced gastrointestinal (GI) cancers. The results, recently published in The Lancet Oncology, show encouraging [...]
