West Virginia (WV) has reported influenza activity as “Widespread” for the week ending Saturday, February 18, 2017.
Influenza activity continues to increase in the United States, flu activity this season has been moderate so far, with severity indicators within the range of what has been seen during previous seasons during which influenza A (H3N2) viruses have predominated. Influenza A (H3N2) predominant seasons are often associated with more severe illness, especially in young children and people 65 and older. For the week ending February 18th, the proportion of people seeing their health care provider for influenza-like illness (ILI) increased to 5.2%. This is above the national baseline of 2.2%. Visits to healthcare providers for ILI have been at or above baseline for nine weeks so far this season. For the last 15 flu seasons, the average duration of a flu season by this measure has been 13 weeks, with a range from one week to 20 weeks. Nine influenza-associated pediatric deaths were reported to CDC during the week ending February 18th, bringing a total of 29 influenza-associated pediatric deaths reported for 2016-17 season.
West Virginia influenza activity has increased. Outbreaks of influenza continue to be reported in long-term care facilities across the state. An increased number of influenza associated outbreaks have also been reported in schools experiencing high rates of absenteeism. The percentage of those seeking care for ILI reported through West Virginia Outpatient ILI Surveillance Network (ILINet) increased to 2.9%, above our state baseline of 2.2%. The predominate strain circulating in WV is influenza A (H3N2), although there has been a significant number of influenza B viruses detected around the state. In a typical influenza season only sporadic cases of influenza B have been reported, but during the 2016-17 influenza season upward of 30% of positive respiratory specimens have tested positive for influenza B.
The Centers for Disease Control and Prevention (CDC) released on Friday February 17, 2017 a report on the effectiveness of the season influenza vaccine for the 2016-17 season. Early estimates indicate that flu vaccines this season have reduced a vaccinated person’s risk of getting sick and needing medical care because of flu by about half (48%). Even during seasons when vaccine effectiveness is reduced, vaccination can offer substantial benefit and might reduce the likelihood of severe outcomes such as hospitalization and death.
Health care providers should continue to offer and encourage vaccination to all unvaccinated persons aged ≥6 months if influenza viruses are circulating, influenza antiviral medications are an important adjunct to vaccination in the treatment and prevention of influenza. Now is still a good time to get vaccinated. It is likely that flu activity will continue for several more weeks this season, so getting vaccinated now can still provide protection this season. For more information on vaccine effectiveness for the 2016-17 influenza season you can view the latest Morbidity and Mortality Weekly Report (MMWR) at: https://www.cdc.gov/mmwr/volumes/66/wr/mm6606a3.htm?s_cid=mm6606a3_w.
Weekly influenza surveillance graphs for WV and the most recent information can be found at http://www.dhhr.wv.gov/oeps/disease/flu/Pages/default.aspx. Because of late reporting, the information is sometimes updated in retrospect. The website will always have the most up-to-date numbers. Please feel free to contact the Division of Infectious Disease Epidemiology at (304) 558-5358, extension 1, with any questions regarding this report.