When many people first think of a virus they immediately think of the flu. This infamous virus is one that everyone dreads and takes great precautions, like vaccines, to avoid contracting. According to the CDC’s latest Flu Report, the occurrence of the virus within the United States has steadily increased in the last 3 weeks. This is evident in the larger percentage of positive clinical lab results that have increased from 28.4% to 29.8% in the last week. As well as the increase in positive lab tests for the flu, the majority of states/jurisdictions have reported local or widespread influenza during the last week of January.
This increase in the occurrence of the influenza virus within the United States has ultimately resulted in various other factors to become more common as well. For example, within the past week, the number of people hospitalized who had contracted the influenza virus increased to 35.5% per 100,000 cases. The percentage of patient deaths attributed to influenza and secondary infections like pneumonia has also increased to about 7.1% of patients. Those that have the flu are more likely to contract secondary infections, such as pneumonia, as the contraction of the influenza virus makes them immunocompromised and therefore not as able to fight off other infections. The total pediatric deaths caused by influenza this season so far is 78, with 10 of those deaths occurring in the last week of January.
As the flu season begins to reach its peak, it’s important to understand the types of viruses that are being spread. For this season, it appears that nationally a specific B virus, B/Victoria, and a specific A virus, A(H1N1)pdm09, are the strains that have been contracted the most. While type B virus outbreaks occur each year and are often not as severe, type A viruses tend to cause widespread epidemics and infections with more severe symptoms. While the CDC has stated that they do not yet have concrete data on the effectiveness of the vaccines for this flu season, they have concluded some similarities between the strains being spread this season and the strains that were included in the vaccine. For example, the viruses in the vaccine seem to share similarities with the A(H1N1)pdm09 and the B/Yamagata being spread this flu season. However, the CDC has found that the viruses within the vaccine have a reduced similarity to the B/Victoria and A(H3N2) viruses that have been seen this season. Regardless of the effectiveness of the vaccine, it is still important to receive a flu vaccine each season as it could ultimately lessen the severity of signs and symptoms if one contracts the influenza virus.
Resources
“Frequently Asked Influenza (Flu) Questions: 2019-2020 Season.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 17 Jan. 2020, https://www.cdc.gov/flu/season/faq-flu-season-2019-2020.htm.
“Weekly U.S. Influenza Surveillance Report Prepared by the Influenza Division.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 7 Feb. 2020, https://www.cdc.gov/flu/weekly/#S5.
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