Influenza A(H3N2) viruses predominate 2017-2018 season

February 16, 2018

(HealthDay)—Most influenza viruses identified in the 2017 to 2018 season are influenza A, with A(H3N2) viruses predominating, according to research published in the Feb. 16 issue of the U.S. Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report.

Alicia P. Budd, M.P.H., from the CDC in Atlanta, and colleagues examined in the United States from Oct. 1, 2017, through Feb. 3, 2018. The researchers observed an increase in influenza activity in early November 2017, followed by a sharp increase from December through Feb. 3, 2018. The most commonly identified viruses were influenza A viruses, with A(H3N2) viruses predominating; influenza A(H1N1)pdm09 and influenza B viruses were also reported. A total of 17,101 laboratory-confirmed influenza-related hospitalizations were reported during the study period (cumulative incidence, 59.9 per 100,000 population).

Brendan Flannery, Ph.D., also from the CDC, and colleagues used data from 4,562 children and adults enrolled in the U.S. Influenza Vaccine Effectiveness Network during Nov. 2, 2017, to Feb. 3, 2018. The researchers found that the overall adjusted vaccine effectiveness (VE) against influenza A and influenza B infection correlated with medically-attended acute respiratory illness was 36 percent. Sixty-nine percent of influenza infections were caused by A(H3N2) viruses. VE was estimated to be 25, 67, and 42 percent against illness caused by influenza A(H3N2) viruses, A(H1N1)pdm09 viruses, and influenza B viruses, respectively.

"These early VE estimates underscore the need for ongoing influenza prevention and treatment measures," Flannery and colleagues write. "Even with current vaccine effectiveness estimates, vaccination will still prevent illness, including thousands of hospitalizations and deaths."

Explore further: Influenza picking up in U.S., predominantly A(H3N2)

More information: Abstract/Full Text - Budd
Abstract/Full Text - Flannery

Related Stories

Influenza picking up in U.S., predominantly A(H3N2)

December 8, 2017
(HealthDay)—Influenza activity was low during October 2017 but started increasing in November, with influenza A, predominantly A(H3N2), most commonly identified, according to research published in the Dec. 8 issue of the ...

CDC: Influenza vaccine 48 percent effective overall

February 20, 2017
(HealthDay)—This year's influenza vaccine is a fairly good match for the circulating viruses, according to research published in the Feb. 17 issue of the U.S. Centers for Disease Control and Prevention's Morbidity and Mortality ...

Expert says vaccination is still recommended for flu despite decreased effectiveness

January 22, 2018
As the UK currently experiences the worst influenza season since the winter of 2010/2011, influenza expert Dr. Jeremy Rossman of the School of Biosciences at the University, worries that 'the number of cases will continue ...

Live attenuated flu vaccine not effective for children in 2015-16

August 10, 2017
(HealthDay)—During the 2015 to 2016 season, influenza vaccines reduced the risk of influenza illness, but the live attenuated vaccine was ineffective among children 2 to 17 years of age, according to a study published in ...

Tough flu season ahead: vaccine may only be 10% effective

December 6, 2017
(HealthDay)—There's bad news about this year's flu vaccine.

Severe flu season slams all but one state: CDC

January 13, 2018
(HealthDay)— The worst flu season in years is only getting worse, with 49 states now seeing widespread misery, U.S. health officials report.

Recommended for you

Infants born to obese mothers risk developing liver disease, obesity

November 16, 2018
Infant gut microbes altered by their mother's obesity can cause inflammation and other major changes within the baby, increasing the risk of obesity and non-alcoholic fatty liver disease later in life, according to researchers ...

New study shows NKT cell subsets play a large role in the advancement of NAFLD

November 16, 2018
Since 2015 it has been known that the gut microbiota could have a direct impact on nonalcoholic fatty liver disease (NAFLD), which affects up to 12% of adults and is a leading cause of chronic liver disease. In the November ...

Antibiotic prescribing influenced by team dynamics within hospitals

November 15, 2018
Antibiotic prescribing by doctors is influenced by team dynamics and cultures within hospitals.

Discovery suggests new route to fight infection, disease

November 14, 2018
New research reveals how a single protein interferes with the immune system when exposed to the bacterium that causes Legionnaires' disease, findings that could have broad implications for development of medicines to fight ...

Zika may hijack mother-fetus immunity route

November 14, 2018
To cross the placenta, Zika virus may hijack the route by which acquired immunity is transferred from mother to fetus, new research suggests.

New research aims to help improve uptake of hepatitis C testing

November 14, 2018
New research published in Scientific Reports shows persisting fears about HIV infection may impact testing uptake for the hepatitis C Virus (HCV).

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.