During cold and flu season, many people consider hand sanitizer their best friend, but it might not be effective at killing the flu virus in certain situations, a recent study finds.
In fact, avoiding the flu virus is tough.
When someone has the flu, their body is turned into a virus factory where its producing and spreading the virus in way that can be tricky to defend against.
Hand sanitizer has its uses, but when it comes to the flu it’s not perfect. One recent study found the flu virus could survive two minutes of hand rubbing with an alcohol-based sanitizer when it’s surrounded by a protective droplet of mucus.
This type of spread would result from direct contact or when fresh droplets are spread from a sneeze. Without the mucus, the flu didn’t last more than 30 seconds against hand sanitizer.
The same study found hand washing was universally more effective than hand sanitizer.
Another recent study finds that just breathing or talking may be all it takes to spread infectious particles in the air.
The influenza virus was found to live on many hard surfaces, like light switches and computer keyboards, for as long as nine hours. However, it did not last very long on soft and porous surfaces like facial tissues, cloth and wood.
Researchers found that humidity is one of the most important factors in how long the virus able to survive — and one the most important things you can control to reduce the spread of the virus.
In one study, at relatively low humidity levels, five times more virus remained in the air an hour after a cough compared to an environment with high humidity.
In the winter, humidity naturally decreases, which is one of the proposed reasons the flu spreads more easily during winter. Lower humidity also makes it harder for our respiratory tract to protect us from the flu.
Bottom line: Don’t rely on hand sanitizer this season, if you have the flu, stay home, use a humidifier and try not to spread it.