Although it can sometimes be challenging, there are ways to tell apart respiratory symptoms caused by a virus and those caused by an allergy. This approach may help prevent Australia’s COVID-19 testing capacity from being overwhelmed.
We’re told to stay home if we feel unwell during the COVID-19 pandemic. But what if your sniffles, sore throat or cough aren’t infectious? What if they’re caused by hayfever or another allergic reaction? You may be doing a lot more isolating than you need to.
Hayfever has many of the same symptoms as viral respiratory infections, such as colds and mild flu-like illnesses, as well as COVID-19. This is because rhinitis refers to inflammation of the nose, which has many causes.
What are the symptoms of Allergy?
Whether you have seasonal hayfever, longer-term perennial or vasomotor rhinitis), or a viral infection, you’re likely to have similar cold and flu-like symptoms.
You’ll have either a runny or stuffy nose. Other symptoms include sore throat; sneezing; cough; post-nasal drip – nasal mucus going down the back of your throat; and fatigue.
But there are two classic hayfever symptoms that can help you tell allergies and viruses apart. Hayfever can cause you to have an itchy nose or throat; and when it’s more severe it can cause swollen, blue-coloured skin under the eyes (called allergic shiners).
Can we tell them apart?
Fever, sore muscles or muscle weakness
Hayfever, despite its name, does not cause increased body temperature. Flu-like illnesses do cause fever, and sore muscles (myalgia), malaise and fatigue.
Allergies such as hayfever may cause a slight malaise without the other symptoms, probably due to a stuffy nose and poor sleep.
Itchy nose and eyes, plus sneezing
An itchy nose and eyes are classic hayfever symptoms, as is intense, prolonged sneezing.
You can sneeze with a cold or flu, but usually only in the first few days of the infection.
Longer-lasting symptoms
Allergic reactions tend to come and go from day to day, or even from hour to hour, particularly if some environments are the source of the offending allergens. Perennial rhinitis can be present for weeks or months, far longer than any viral cold or flu.
It is rare for a cold to last more than a week, as the body has fought off the virus by that time. Exceptions to this are the cough and sinus symptoms that were triggered by the virus but persist for other reasons.