It is possible to contract influenza, commonly known as the flu, during the summer months, although it is significantly less common than during the colder seasons. While the flu virus is typically associated with fall and winter, it does not disappear entirely in warmer weather.
Why Flu is Seasonal
The seasonality of influenza is influenced by environmental factors and human behaviors. Colder temperatures and lower humidity levels create conditions that allow the influenza virus to survive longer and spread more efficiently in the air. Low humidity can also impair the immune system’s ability to defend against the virus by affecting the function of cilia, which are hair-like structures that help clear viral particles from airways.
Human behavior also plays a considerable role in the spread of the flu during colder periods. People tend to spend more time indoors in closer proximity to one another during the fall and winter, increasing opportunities for the virus to transmit from person to person. This increased indoor congregation, combined with environmental conditions, contributes to the typical flu season experienced in temperate regions. Flu viruses are constantly evolving, leading to the development of new strains each year, which necessitates annual vaccine updates.
Understanding Summer Flu
Despite its strong seasonal pattern, influenza viruses circulate throughout the entire year across the globe. While flu activity generally remains low in the Northern Hemisphere during summer, cases can still emerge. The symptoms of summer flu are identical to those experienced during winter, including fever, chills, body aches, sore throat, and cough.
One common way people can contract the flu in summer is through international travel. When it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere, where flu season is in full swing. Travelers returning from or visiting these regions can bring different flu strains back with them. Crowded indoor environments such as airports, cruise ships, and large gatherings like festivals or concerts, can also facilitate virus transmission regardless of the outdoor temperature. Many other viruses, such as common cold viruses, enteroviruses, or RSV, can cause flu-like symptoms during the summer, which may sometimes be mistaken for influenza.
Strategies for Prevention
Preventing the flu involves adopting several practical measures that limit the spread of respiratory viruses. Frequent and thorough handwashing with soap and water for at least 20 seconds is highly effective. If soap and water are unavailable, an alcohol-based hand sanitizer containing at least 60% alcohol can be used.
Here are other preventive actions:
- Avoid touching your eyes, nose, and mouth, as these are common entry points for viruses.
- Cover coughs and sneezes with a tissue or into your elbow, and dispose of used tissues promptly.
- Stay home when feeling unwell to prevent further transmission to others.
- Clean and disinfect frequently touched surfaces to reduce the presence of viruses.
- Get an annual flu vaccine, recommended by the Centers for Disease Control and Prevention (CDC) for everyone six months and older, as it is the most significant step in reducing the risk of illness and its potential severity.