COVID-19 is no longer considered a global emergency but it has changed the way other viruses behave -- at least for now.
Dr. Brian Conway, medical director of the Vancouver Infectious Diseases Centre (VIDC), says that the "pandemic seemed to have confused viruses," resulting in an early start to the respiratory season as well as cases continuing into the summer months.
Canada declared an influenza epidemic in November 2022 following a surge in cases and an early start to the flu season. The Public Health Agency of Canada warned that the country faced a "triple threat" of respiratory diseases, which included the flu, COVID-19, and the respiratory syncytial virus (RSV).
While cases of COVID-19 have waned, Canada continues to report over 1,000 cases of the coronavirus weekly -- and those only include people who get tested by a healthcare professional.
Conway attributes a rise in other respiratory illnesses to a loosening of pandemic-related restrictions, noting that this is the first year Canadians didn't have to follow any guidance from their local health authorities.
Viruses transmit from person to person and have more opportunities to spread during colder months when they spend time close together indoors. The respiratory season typically stays fairly consistent but pandemic restrictions prevented people from being exposed to viruses for at least two years.
Conway notes that the population's immunity may have waned, making people "more susceptible" to respiratory diseases.
People who feel ill should continue to follow best practices, including staying home when they have symptoms and wearing masks when it is appropriate.
"We are getting a bit tired and complacent," he told V.I.A., adding that people who venture out while ill can also pick up secondary diseases more easily. "Once you have one [virus], you're more susceptible to getting other things."
People who are diagnosed with COVID-19 within the first few days of showing symptoms should also take Paxlovid, which can reduce the length and severity of infection, advises Conway, who adds that he offers the drug to patients who get a positive result early.
What is the difference between COVID symptoms and other respiratory diseases?
While many symptoms of respiratory diseases overlap, there are some notable differences between them.
The BCCDC says symptoms of COVID-19 may include new or worsening:
- Fever or chills
- Cough
- Loss of sense of smell or taste
- Difficulty breathing
- Sore throat
- Loss of appetite
- Runny nose
- Sneezing
- Extreme fatigue or tiredness
- Headache
- Body aches
- Nausea or vomiting
- Diarrhea
While all of the above symptoms may range in severity, seek medical attention if you:
- find it hard to breathe
- have chest pain
- can’t drink anything
- feel very sick
- feel confused
Know the other viruses: RSV, HMPV
RSV is a common respiratory virus that typically causes mild symptoms, including a "simple cold, or bronchiolitis in young infants," according to the BC Centre for Disease Control (BCCDC).
While RSV typically goes away with home treatment, babies younger than six months, especially those born prematurely, may require hospital treatment. The virus can block their much smaller airways and have a significant effect on them. Last fall saw a surge in RSV cases in children in B.C., according to Conway.
RSV may also cause severe disease in men and women over age 65. Unlike other respiratory viruses, it typically doesn't affect teenagers and adults under 65.
Instead, people typically develop a type of immunity to the virus that wanes over time. It can then lead to "very serious pneumonia and even death," he said. The U.S. is making progress on a vaccine; Canada does not currently have an RSV vaccine.
Metapneumovirus (HMPV), which was first identified in 2001, is similar to RSV but the symptoms are milder and closer to a common cold, including a cough, a bit of a fever, and a runny nose. Young children and people over age 65 or who are immunocompromised are more susceptible to developing complications from an infection, such as pneumonia.
"By and large, it is much more like the common cold than influenza or RSV," noted Conway.
Do you have a cold, the flu, or allergies? Check your symptoms
Symptoms of influenza can include fever, headache, muscle pain, runny nose, sore throat, extreme tiredness, and cough. Flu symptoms tend to be worse than those caused by other viruses. The virus affects people of all ages and symptoms begin one to four days after a person is exposed. While symptoms last up to 10 days, general weakness and a residual cough may last over two weeks, according to the BCCDC.
The common cold, on the other hand, typically doesn't cause a fever or headache, and typically causes milder symptoms. An infected person typically has a stuffy nose, sneezing, and a sore throat, and they may develop a sinus infection.
When it comes to differentiating cold symptoms from allergies, Conway says an allergy response typically causes watery, itchy eyes in addition to a runny nose and a cough. That said, a person suffering from seasonal allergies may only show one or two of these symptoms.
And while COVID-19 often causes severe cough and a change in taste or smell, non-respiratory symptoms, including nausea and vomiting, are also common. Taking a rapid test can determine if you have COVID-19 but it is important to get plenty of rest, stay hydrated, and stay at home while you're sick, regardless of what virus is causing the illness.
"Let's not abandon our masks and get in the habit of going to work while we're sick," Conway emphasized.
