On cusp of flu season, Michigan looks to improve vaccination rates

With flu season fast approaching, the most recent figures from the Centers for Disease Control and Prevention are far from encouraging.

An estimated 80,000 Americans died of flu and flu-related complications last winter, according to Dr. Robert Redfield, the director of the CDC. That would make the last flu season the deadliest in more than four decades.

The uptick in flu-related deaths was driven by a kind of flu that tends to be more severe, particularly among vulnerable populations like children and the elderly.

Last year was also a poor year for the effectiveness of the flu vaccine, which changes every year to adapt to the ever-changing virus. A February study from the CDC’s Morbidity and Mortality Weekly Report found that the flu shot was 36 percent effective, meaning that the vaccine reduced the risk of flu sickness and a doctor’s visit by a little over a third.

But the study also found that the vaccine’s effectiveness against H3N2, the viral strain that was the main culprit of flu sickness in the United States last winter, was only 25 percent. Similarly, a Canadian study found the flu vaccine was only 17 percent effective against H3N2.

Still, experts say that vaccines remain the best way to reduce the severity of the flu and to save lives.

“It’s a very safe vaccine, it’s inexpensive, it’s readily available, and it’s relatively effective, so it’s our best means of preventing the flu,” says Dr. Daniel Salmon, a vaccine expert at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Md.

Research has also shown that flu vaccinations are proven to reduce the risk of flu illness. A 2017 study by the CDC found that the full vaccination reduced the risk of flu-related death by nearly two-thirds among healthy children, and a study published last month showed that the vaccination lessened the severity of the illness among adults.

In recent years, however, Michigan has been stricken by the spread of diseases considered to be “vaccine-preventable.” In February, Michigan had the first flu-related child death in the U.S. for 2018, and last month, three Michigan residents tested positive for influenza A H1N1 virus after attending a conference in Grand Rapids. Hepatitis A broke out between August 2016 and June 2017 in Southeast Michigan, prompting the Michigan Department of Health and Human Services to classify the outbreak as “a significant public health threat.” Michigan also recorded its highest tallies for measles cases — 10 so far this year, nine of which stemmed from Washtenaw County — in the past 20 years.

The outbreaks and the deaths can be partially attributed to a low vaccination rate in the state, according to public health experts. The CDC estimates that 44.2 percent of Michigan residents were vaccinated against the flu, the 33rd highest state vaccination rate in the country.

“As we see the vaccination rate go up, we will expect to see reduced influenza transmission to people who are highly vulnerable and can’t get vaccinated on their own,” says Dr. Emily Martin, an assistant professor of epidemiology at the University of Michigan who researches the effectiveness of the flu vaccine.

“The very young and the very old are the most vulnerable, and they may not be able to access [or] respond to vaccines as well as a child or healthy adult,” Dr. Martin says.

The metro Detroit area, in particular, has room to improve its vaccination rate. State data for the 2017-2018 flu season shows that Wayne County ranked among the lower half of all counties for vaccination rates across all age groups. A study published in June this year that collected data from state health departments and the CDC also found that Wayne County had some of the highest non-medical vaccination exemption rates among kindergarten-aged children in the nation.

Courtesy PLOS Medicine