The H3N2 influenza virus is at its peak this flu season with over 35,000 cases and 65 deathsin the state of Pennsylvania alone. This strain is more likely to cause serious illness or death, especially the elderly and young children, than other strains in previous years. While many argue about the effectiveness of this year’s vaccine, with reports indicating a 30 percent success rate, medical microbiologist Michael McCann, Ph.D. ’87, professor of biology at Saint Joseph’s University in Philadelphia, still recommends getting the flu shot.
“The vaccine’s effectiveness – or lack thereof – this year depends on what happened when the viruses were being grown in the lab,” says McCann. “The H3N2 virus that was used in this year’s vaccine preparations mutated early on in the process, making it different from the strain infecting people. This means the vaccine cannot provide full protection against it.”
According to McCann, since the flu virus mutates quickly a new vaccine combination needs to be prepared each year.
Months before the American flu season, scientists observe the southern hemisphere to discover what next year’s strains of flu might look like and develop a vaccine based on these predictions. “Some years, the predictions aren’t absolutely correct,” explains McCann. “A predominant strain in the southern hemisphere may be different than what arises here.”
Although the effectiveness of a vaccination can vary year to year, McCann thinks it is better to be safe in these instances. “A success rate of 30 percent is better than nothing,” he says. “The worst case scenario is that it doesn’t work for you, while the best case scenario is it prevents you from getting sick.”
Even though the vaccination is the most well-known method for preventing influenza, McCann urges taking conventional precautionary steps to further prevent contracting the virus and spreading it to others. “Cough into the crook of your arm, not onto your hand,” recommends McCann. “When you cough, little water droplets that spread viruses and bacteria get expelled. If you cough into your hand, you are more likely to spread disease causing germs on a door handle and other objects that we are always in contact with.”
He also touts handwashing as vital to preventing the spread of bacteria during flu season. “Using soap and warm water for a good twenty seconds works,” says McCann. “The soap inactivates the virus, and the water gets rid of underlying dirt that hand sanitizers don’t reach.”
If hand sanitizer is your only option, alcohol-based products prevent the spread of disease-causing viruses and germs more effectively than those that are not alcohol-based. “There is scientific evidence that bacteria can evolve resistance to the chemicals in non-alcohol based hand sanitizers,” says McCann.
He adds that the disinfectants used in these hand sanitizers are also used to sterilize medical facilities and equipment, making it crucial that they are not used inappropriately. “Using these chemicals for hand sanitizing when they are not needed increases the risk of bacteria evolving resistance to those disinfectants, which will render them less effective,” says McCann. “Alcohol-based hand sanitizers do not have this drawback and are the best bet when soap and water are not available.”
While many hope flu season is coming to an end by springtime, McCann warns not to relax too soon. “The virus can linger until May in North America,” he warns, “and the data suggests it hasn’t even peaked yet in the Philadelphia area.”