Missouri health officials say it’s too early to tell if flu shot was less effective

Missouri has seven times the number of confirmed flu cases compared to this time last year. But health officials say it’s too early to say if the flu shot is less effective this year or if the flu season peaked earlier.

According to the Missouri Department of Health and Senior Services, as of Jan. 6 there have been 30,932 laboratory-confirmed cases of influenza reported in Missouri so far this flu season, compared to 4,151 at the same time last year.

Boonville R-1 School District closed Friday due to a high number staff and students with the flu, according to Boonville officials.

Trina Teacutter, a nursing supervisor at the Columbia/Boone County Department of Public Health and Human Services, said she thinks it’s too early to tell if flu rates are truly increasing this year. While there is no doubt the number of cases reported are higher than they were last year at this time, it’s possible both Boone County and Missouri are simply hitting an early peak in reported cases. 

The total number of flu cases in the state at the end of last year was at 71,469. In 2016, the total was 20,101, and in 2015 there were 54,316 total flu cases reported.

The Columbia/Boone County Department of Public Health and Human Services has reported a total of 1,066 cases of the flu in Boone County, with 384 of those cases having been reported in the first week of January.

These numbers only represent those cases that have been reported to Public Health and Human Services as laboratory confirmed cases, so the exact number of cases is unknown. Not everyone that gets the flu visits their medical provider, and not everyone who does is laboratory tested for the flu.

According to Teacutter, the trend in the number of flu cases this year mirrors that of 2014. At the end of the flu season in 2014, a total of 2,399 flu cases were reported. In 2015, 782 cases were reported, and in 2016, there were 1,452 cases. 

Vaccine effectiveness

Flu shot effectiveness varies from year to year for several reasons, including strain mutations and the types of strains that are spread during a particular season.

Flu vaccines have multiple different strains of the flu in them. Researchers use a surveillance site and reference labs to collect information about which strains are expected to circulate in the coming flu season each year. Based on the data gathered, three or four strains are chosen to be included in the flu vaccine that year. 

And though the amount of flu cases far outpaces last year, the CDC is predicting the effectiveness of the vaccine this year to be similar to that of last year. Last year, the flu vaccine was 39 percent effective.

It’s not too late to get vaccinated — even halfway through flu season. Although someone may have already been diagnosed with the flu, it’s still worth getting the vaccination, Teacutter explained.

“The most important thing people can do to help our family and loved ones is to get the vaccination rates up,” Teacutter said.

The Centers for Disease Control and Prevention reported that only 2 out of every 5 people in the U.S. gets a flu vaccine each year.

This year, the Health Department has given 12,957 flu vaccines, and is expecting to give more as the flu season continues. In past years there were:

  • 12,590 vaccines given in 2016
  • 11,374 vaccines given in 2015
  • 13,897 vaccines given in 2014

Preventative actions

To be protected from the flu, the CDC recommends getting a flu vaccine every year. In addition to the vaccine, people should take every day preventive actions such as washing their hands often, staying home if they are sick with the flu and coughing in their sleeve as opposed to their hands.

Visit the City of Columbia’s website for updates on the 2017-2018 flu season in Boone County. For more information about the flu visit the CDC’s website.