SIOUX FALLS, S.D. (KELO) — Influenza is an ever-changing virus. It seems the symptoms differ every year. The Centers for Disease Control and Prevention keep track of the different types of strains of flu viruses.
According to the CDC’s page, it uses genetic characterization for the following reasons:
- To determine how closely “related” or similar flu viruses are to one another genetically
- To monitor how flu viruses are evolving
- To identify genetic changes that affect the virus’ properties. For example, to identify the specific changes that are associated with influenza viruses spreading more easily, causing more-severe disease, or developing resistance to antiviral drugs
- To assess how well an influenza flu vaccine might protect against a particular influenza virus based on its genetic similarity to the virus
- To monitor for genetic changes in influenza viruses circulating in animal populations that could enable them to infect humans.
The Centers for Disease Control and Prevention officials say of all the influenza viruses that routinely circulate and cause illness in people, influenza A viruses tend to change more rapidly. Influenza B viruses generally change more slowly in terms of their genetic and antigenic properties than influenza A viruses.
The CDC assesses flu severity by using the following data:
- The percentage of visits to outpatient clinics for ILI,
- The rates of influenza-associated hospitalizations, and
- The percentage of deaths resulting from pneumonia or influenza that occurred during each season.
Doctor Jennifer McKay is a hospitalist for Avera Health. She says the flu strains in South Dakota vary from year to year, but the symptoms remain the same.
“The flu is kind of an interesting bug biologically. What will happen is it will kind of shift it’s outer-protein membrane every five to ten years, or so. So that, the CDC when they’re looking at what flu strain to vaccinate against, is trying to play a little guess work in terms of the genetics of that virus,” McKay said.
Schools are taking extra precautions for all strains of the flu.
“We do have hand sanitizer available throughout the schools and students using those is always a good additional step to prevent the spreading of those germs,” Sioux Falls School District Health Services Coordinator, Molly Satter said.
“The bottom line is, if you do get the flu and you haven’t had a vaccine most likely it’s going to be worse than if you had gotten it,” McKay said.
“Keep them home if they need to be home, but once they’re better we want them back,” Satter said.