Hay fever (also called allergic rhinitis) affects 24% of Australians. Symptoms include sneezing, a runny nose (which may feel blocked or stuffy) and itchy eyes. People can also experience an itchy nose, throat or ears.

But COVID is still spreading, and other viruses can cause cold-like symptoms. So how do you know which one you’ve got?

Remind me, how does hay fever cause symptoms?

Hay fever happens when a person has become “sensitized” to an allergen trigger. This means a person’s body is always primed to react to this trigger.

Triggers can include allergens in the air (such as pollen from trees, grasses and flowers), mold spores, animals or house dust mites which mostly live in people’s mattresses and bedding, and feed on shed skin.

When the body is exposed to the trigger, it produces IgE (immunoglobulin E) antibodies. These cause the release of many of the body’s own chemicals, including histamine, which result in hay fever symptoms.

People who have asthma may find their asthma symptoms (cough, wheeze, tight chest or trouble breathing) worsen when exposed to airborne allergens. Spring and sometimes into summer can be the worst time for people with grass, tree or flower allergies.

However, animal and house dust mite symptoms usually happen year-round.

What else might be causing my symptoms?

Hay fever does not cause a fever, sore throat, muscle aches and pains, weakness, loss of taste or smell, nor does it cause you to cough up mucus.

These symptoms are likely to be caused by a virus, such as COVID, influenza, respiratory syncytial virus (RSV) or a “cold” (often caused by rhinoviruses). These conditions can occur all year round, with some overlap of symptoms:

Credit: Natasha Yates/The Conversation

COVID still surrounds us. RSV and influenza rates appear higher than before the COVID pandemic, but it may be due to more testing.

So if you have a fever, sore throat, muscle aches/pains, weakness, fatigue, or are coughing up mucus, stay home and avoid mixing with others to limit transmission.

People with COVID symptoms can take a rapid antigen test (RAT), ideally when symptoms start, then isolate until symptoms disappear. One negative RAT alone can’t rule out COVID if symptoms are still present, so test again 24–48 hours after your initial test if symptoms persist.

You can now test yourself for COVID, RSV and influenza in a combined RAT. But again, a negative test doesn’t rule out the virus. If your symptoms continue, test again 24–48 hours after the previous test.

If it’s hay fever, how do I treat it?

Treatment involves blocking the body’s histamine release, by taking antihistamine medication which helps reduce the symptoms.

Doctors, nurse practitioners and pharmacists can develop a hay fever care plan. This may include using a nasal spray containing a topical corticosteroid to help reduce the swelling inside the nose, which causes stuffiness or blockage.

Nasal sprays need to be delivered using the correct technique and used over several weeks to work properly. Often these sprays can also help lessen the itchy eyes of hay fever.

Drying bed linen and pajamas inside during spring can lessen symptoms, as can putting a smear of Vaseline in the nostrils when going outside. Pollen sticks to the Vaseline, and gently blowing your nose later removes it.

People with asthma should also have an asthma plan, created by their doctor or nurse practitioner, explaining how to adjust their asthma reliever and preventer medications in hay fever seasons or on allergen exposure.

People with asthma also need to be alert for thunderstorms, where pollens can burst into tinier particles, be inhaled deeper in the lungs and cause a severe asthma attack, and even death.

What if it’s COVID, RSV or the flu?

Australians aged 70 and over and others with underlying health conditions who test positive for COVID are eligible for antivirals to reduce their chance of severe illness.

Most other people with COVID, RSV and influenza will recover at home with rest, fluids and paracetamol to relieve symptoms. However, some groups are at greater risk of serious illness and may require additional treatment or hospitalization.

For RSV, this includes premature infants, babies 12 months and younger, children under two who have other medical conditions, adults over 75, people with heart and lung conditions, or health conditions that lessen the immune system response.

For influenza, people at higher risk of severe illness are pregnant women, Aboriginal people, people under five or over 65 years, or people with long-term medical conditions, such as kidney, heart, lung or liver disease, diabetes and decreased immunity.

If you’re concerned about severe symptoms of COVID, RSV or influenza, consult your doctor or call 000 in an emergency.

If your symptoms are mild but persist, and you’re not sure what’s causing them, book an appointment with your doctor or nurse practitioner. Although hay fever season is here, we need to avoid spreading other serious infections.