Some symptoms can occur due to both allergic reactions and COVID-19, which the new coronavirus, SARS-CoV-2, causes. However, in most cases, there are ways of telling the difference between these causes.
All data and statistics are based on publicly available data at the time of publication. Some information may be out of date.
During the COVID-19 pandemic, developing certain symptoms, such as a cough, can be concerning. However, these symptoms are not necessarily a sign that a person has contracted the coronavirus.
With the temperature dropping, some people are finding that their seasonal allergies are flaring up. Allergies cause symptoms that can seem concerningly similar to those of COVID-19. However, there are ways of telling COVID-19 and allergies apart.
If a person has not had an allergy flare-up before, they may not know whether what they are experiencing is normal. Other factors, such as climate change, are causing seasonal triggers to occur at different times. It can be confusing if allergic responses are starting earlier or later in the year than a person expects.
Keep reading to learn more about the differences between the symptoms of allergies and those of the disease resulting from the new coronavirus.
An allergic reaction is the body’s response when the immune system is sensitive to certain substances, known as allergens. Allergies can involve reactions to allergens outside the body, such as dust, or those inside, such as after eating food containing nuts.
Allergies are individual and do not pass between people. Although allergic reactions can sometimes be severe, they are more often minor, causing symptoms that are irritating but not threatening to health.
When allergies flare up, they can cause responses that have worrying similarities to COVID-19. Some people experience allergies year-round, while others have more seasonal allergies, such as hay fever.
Symptoms of COVID-19 include, among others:
It is possible to have the coronavirus and experience few or no symptoms.
Different substances can cause allergic reactions, but they often trigger similar symptoms. These include:
- congestion or runny nose
- shortness of breath
Regarding symptoms, a key difference to note is fever. If a person has a fever, it is extremely unlikely that they are only experiencing an allergy. Instead, they may have a type of illness, such as the flu or, possibly, COVID-19.
The main difference between the coronavirus and allergies is that COVID-19 is a contagious respiratory disease, whereas allergies are not infectious and often affect the sinuses.
There is an overlap in symptoms between allergies and COVID-19, but the likelihood of developing certain symptoms differs.
Nasal symptoms are one example. COVID-19 occasionally causes congestion, but this is not common. Only 5% of people with COVID-19 develop symptoms in the nose. Meanwhile, allergies nearly always cause the symptoms of a stuffy or runny nose.
Another common nasal symptom is sneezing. Allergies often cause sneezing, but people with COVID-19 do not usually have this symptom.
Itchiness is another example of a symptom that may help people determine the condition affecting them. Allergies may cause itchiness, but this does not happen with the coronavirus.
Conversely, allergies are not usually associated with changes in taste or smell, but COVID-19 is strongly associated with these.
Another indication of COVID-19 is the co-occurrence of fever and cough. An allergic response is unlikely to cause these two symptoms together.
With allergies, a person may develop a cough as an allergic reaction to external triggers, such as dust or cockroaches, or as part of an asthmatic response to allergens. However, despite the name of the seasonal allergy hay fever, allergies do not cause fever.
Symptoms of allergies vary depending on the allergen, but some similarities that cause concern are:
- shortness of breath
- sore throat
- persistent dry cough
If a person is only experiencing the symptoms in the list above, it is harder to determine what is causing them.
A person should consider what their activities were just before the start of the symptoms and whether any substances, such as pollen, worsen the symptoms.
If a person suspects an allergy, they can try taking allergy medications, such as antihistamines, to see whether these relieve the symptoms.
If the cause of the symptoms is still unclear, or the person may have had exposure to the coronavirus, they should apply for a SARS-CoV-2 test.
If a person is unsure whether their symptoms are due to an allergy or COVID-19, they should first consider the possible causes of allergic reactions.
For example, they can question whether it is the right time of year for a seasonal allergy and how exposure to different environments affects their symptoms.
If a person knows that they have hay fever, they can compare the current pollen count in their area with that the week before to see whether it has increased.
Similarly, a person with a known or suspected food allergy can check whether any of their recent meals contained ingredients that may have caused a reaction.
It is important to remember that COVID-19 and an allergy flare-up can occur at the same time. Due to this, symptoms can seem confusing, particularly if a person is experiencing some from each cause.
If a person is concerned that they may have the novel coronavirus, they should get a test.