Cold and flu symptoms can potentially last four weeks or more after infection, according to new research.
The study, led by Queen Mary University of London (QMUL), was published in the Lancet’s EClinicalMedicine journal Friday.
Researchers compared long-term symptoms between long COVID sufferers and those infected with other respiratory illnesses, such as pneumonia, influenza, bronchitis and the common cold. Out of 16 symptoms observed, some of the most common reported were coughs, stomach pain and troubling sleeping after initial infection.
The findings suggest that there may be long-term health impacts associated with other respiratory illnesses besides COVID, which have gone unrecognized, the study says.
“The scale and fast spread of the COVID-19 pandemic, alongside a lower case–fatality ratio than previous coronavirus pandemics, has resulted in hundreds of millions of survivors globally over just a few years, focusing attention on their post-COVID experience,” the study says.
However, while the findings point to possible long-term health impacts following a common cold or flu, the evidence does not yet suggest that symptoms have the same severity or duration as long COVID.
Long-term symptoms associated with a non-COVID respiratory illness appeared to differ a bit from long COVID symptoms, with the latter reporting greater challenges with taste and smell, as well as lightheadedness and dizziness.
The former group also reported a smaller prevalence of muscle or joint pain and hair loss.
Both groups experienced a range of gastrointestinal, neurological, musculoskeletal and cardiopulmonary problems.
The severity of the acute infection also seemed to play a role in the risk for long-term symptoms.
Long COVID is broadly defined by Health Canada as a condition when the symptoms of COVID-19 persist for more than 12 weeks after an infection.
A report, called “The Immunology of long COVID” published by the science journal Nature on July 11, warns that the condition, which affects millions of people globally, presents a burden to patients, health-care providers, governments and economies that is “unfathomable.”
The report says the disease is “multi-organ (and) multisystem,” and that even infections without symptoms can cause organ damage. There is also evidence that the virus can remain in a person’s body and cause micro blood clots.
Researchers at QMUL looked at data from 15,688 participants who completed a questionnaire between January and February of 2021. Around 10,000 were included in the study’s analysis.
The study found that those with non-COVID illnesses are more likely to report having a cough or a hoarse voice than those with COVID. Both groups experienced breathlessness and fatigue.
Participants with long COVID showed a higher probability of memory problems, difficulty concentrating, an unusual racing heart, sweating, hair loss and problems with taste or smell.
Long COVID sufferers reported a lower burden of coughing, problems with taste or smell and shortness of breath after the 12-week mark compared to those with more recent infections, suggesting that these symptoms may be the first to show improvement.
“Given the few diagnostic tests available, future research needs to focus on enabling diagnosis of long COVID and other post-acute sequelae, to ensure all people with ongoing symptoms can access the support they need,” the study says.