As the weather gets colder and Canadians spend more time indoors, respiratory viruses begin to spread more easily. Every fall, health experts encourage people to prepare for flu season and other respiratory illnesses by getting recommended vaccines. Three of the most important viruses to watch for are influenza (flu), COVID-19, and respiratory syncytial virus (RSV). These viruses can cause mild illness in some people but may lead to serious complications, hospitalization, or even death in others.
The National Advisory Committee on Immunization (NACI) and the Public Health Agency of Canada provide guidance on who should receive vaccines and when. Understanding these recommendations can help Canadians protect themselves, their families, and their communities during the fall and winter months.
Respiratory viruses usually become more common in late fall and winter. People tend to gather indoors, where viruses spread more easily through coughing, sneezing, and close contact. Schools, workplaces, and social events can also increase opportunities for transmission. Season influenza epidemics occur annually in Canada, generally during the late fall and winter months, and COVID-19 continues to circulate year-round with seasonal increases. RSV is also a major cause of respiratory illness during the colder months. Because these viruses often circulate at the same time, getting recommended vaccines can reduce illness, help prevent complications, and decrease pressure on Canada's healthcare system.
Influenza is a contagious respiratory infection caused primarily by influenza A and B viruses. While many people recover within a week or two, influenza can lead to serious complications such as pneumonia and can worsen existing health conditions.
NACI recommends that everyone aged six months and older receive an influenza vaccine every year unless they have a contraindication to vaccination. Annual vaccination is recommended because flu viruses change over time, and protection from previous vaccines declines.
Although everyone can benefit from a flu vaccine, it is especially important for people at higher risk of severe illness. These groups include:
Adults aged 65 years and older.
Children younger than five years of age.
Pregnant individuals.
People with chronic medical conditions such as heart disease, lung disease, diabetes, or weakened immune systems.
Residents of long-term care facilities.
Indigenous Peoples.
Healthcare workers and caregivers.
Individuals who regularly interact with people at high risk of complications.
Vaccinating healthy individuals also helps protect vulnerable populations by reducing the spread of influenza within communities.
NACI recommends receiving the influenza vaccine as soon as it becomes available in the fall. However, vaccination can still provide benefits later in the season because influenza activity often continues throughout the winter months. It takes time for the immune system to build protection after vaccination, so getting vaccinated early helps ensure protection before virus activity peaks.
Although COVID-19 is no longer considered a pandemic emergency, it remains an important public health concern. The virus continues to cause illness ranging from mild symptoms to severe disease requiring hospitalization. Older adults and people with certain medical conditions are still at the highest risk of serious outcomes.
NACI identifies several groups that should be prioritized for COVID-19 vaccination:
Adults aged 65 years and older.
Residents of long-term care homes and other congregate living settings.
People with underlying medical conditions that increase their risk of severe illness.
Pregnant individuals.
First Nations, Inuit, and Métis individuals and communities.
Members of racialized and equity-denied communities.
Healthcare workers and caregivers.
Like influenza viruses, SARS-CoV-2 continues to evolve. Updated vaccines help improve protection against circulating strains and boost immunity that may have declined since a previous vaccination or infection. Vaccination remains one of the most effective ways to reduce the risk of severe disease, hospitalization, and death.
Respiratory Syncytial Virus, commonly known as RSV, is a respiratory virus that infects people of all ages. Most people recover without major problems, but RSV can be dangerous for infants, older adults, and people with certain health conditions. RSV can lead to severe lower respiratory tract disease, hospitalization, and other serious complications.
NACI strongly recommends RSV immunization for adults aged 75 years and older. This recommendation is based on evidence showing that older adults face a significantly higher risk of severe RSV disease and its complications. NACI also strongly recommends RSV vaccination for adults aged 60 years and older who live in nursing homes or other chronic care facilities because residents of these settings are at increased risk of severe outcomes. For adults aged 50 to 74 years, RSV vaccination may be considered based on individual risk factors and discussions with a healthcare provider. Factors such as chronic heart disease, lung disease, weakened immunity, and other medical conditions may also increase the benefits of vaccination.
There is an RSV vaccine authorized in Canada to be given during pregnancy between 32 and 36 weeks of gestation. Vaccination during pregnancy helps pass protective antibodies to the baby before birth, reducing the risk of severe RSV disease during the first months of life. This strategy provides an important layer of protection for newborns, who are among the groups most vulnerable to serious RSV infections.
Almost all children are exposed to RSV by the age of two, and some infants require hospitalization because of severe infections. Older adults can also experience serious outcomes, including pneumonia, hospitalization, intensive care admission, and death. Emerging evidence suggests RSV infection may also be associated with complications such as cardiovascular events in older adults.
Many Canadians wonder whether they need separate appointments for flu, COVID-19, and RSV vaccinations. Health authorities support giving influenza and COVID-19 vaccines at the same visit when appropriate. This can make vaccination more convenient and improve protection before respiratory virus activity increases. The timing of RSV vaccination may vary depending on age, medical conditions, pregnancy status, and provincial vaccination programs. Your pharmacist can help determine the best schedule for you.
Vaccines are one part of a broader strategy to stay healthy during respiratory virus season. Hand washing, covering coughs and sneezes, staying home when sick, and improving indoor ventilation also help reduce the spread of illness. However, vaccination remains one of the strongest tools available to prevent severe disease.
Canadians should stay informed about local public health recommendations because provinces and territories may have specific programs, eligibility criteria, and schedules. People with chronic medical conditions, weakened immune systems, or questions about vaccine timing should consult a their pharmacist for more information.
