Air pollution affects likelihood and severity of flu

As many as one in five adults become sick with the flu every year and many are hospitalized due to flu-related complications

If you live an area with high levels of air pollution, you may run an even greater risk of getting sick with the flu. What’s more, if you get the flu your symptoms are likely to be more severe. Here’s what you should know about the link between the air you breathe and the flu:

Breathing air pollution increases your chances of getting sick with the flu.

Multiple studies have confirmed that exposure to elevated levels of air pollution increases the likelihood that you will become sick with influenza. Some of the specific pollutants associated with an increase in influenza cases include PM10 particulates, diesel exhaust, nitric oxides, sulfur dioxide and ozone. Researchers believe that airborne pollution particles provide “condensation nuclei” to which virus droplets attach. These particles – with virus particles attached – remain airborne longer, allowing the virus to travel much farther than the distance covered when you sneeze.

PM10 and other pollutants: A group of scientists in Hong Kong investigated the relationship between pollution levels and hospital admissions for asthma, pneumonia and influenza. They found the rate of admissions for these conditions increased when levels of nitrogen oxide, ozone and particulate matter (PM10) increased. The increased risk was highest for those more than 65 years of age.

Diesel exhaust: A group of scientists in the U.S. studied the effects of breathing diesel exhaust on the likelihood of getting sick after being exposed to the flu virus. After half of the group was exposed to diesel exhaust for two hours, subjects in the study were given a live flu vaccine and their responses were carefully measured. Viral RNA levels were significantly higher in those who breathed the diesel exhaust for two hours.

If you have the flu, air pollution may make your symptoms worse.

Allergists say polluted air makes symptoms of the flu feel worse for those who are already sick. Pollution particles rub against the bronchial tubes and create inflammation and irritation similar to (and adding to) flu symptoms. This is especially apparent in high-pollution areas where pollution levels often peak during flu season.

Human cells respond to both pollutants and viruses by releasing chemicals called cytokines. Cytokines are proteins that serve as messengers for communications between the body’s cells. The chemicals are released by the body’s immune system, and cause inflammation and the release of fluids.

Steps you can take this flu season