From May 20 to Oct. 13, 1.4 percent of the 197,295 respiratory specimens tested for influenza at U.S. clinical laboratories were positive -- about 65 percent of them positive for influenza A viruses and 35 percent for influenza B viruses.
About 90 percent of the seasonal influenza A viral specimens were subtyped, with about 58 percent of these identified as influenza A (H1N1) and about 42 percent as influenza A (H3N2). For the influenza B specimens, lineage was determined for about 81 percent, with about 80 percent of these identified as B/Yamagata and 20 percent B/Victoria.
This is according to an Oct. 26 CDC Morbidity and Mortality Weekly Report.(www.cdc.gov)
The CDC said surveillance showed there hasn't been significant evidence of antigenic drift among circulating influenza A (H3N2) viruses since the selection of viruses for the 2018-19 Northern Hemisphere vaccines was made in February.
- From May 20 to Oct. 13, U.S. clinical laboratories tested around 197,300 respiratory specimens for influenza, and 1.4 percent were positive, including about 65 percent positive from influenza A viruses and about 35 percent positive for influenza B viruses.
- Another recent CDC report looked backward on the 2017-18 influenza season and found that during that time, the flu caused 79,400 deaths and about 960,000 hospitalizations.
- To support family physicians' vaccination efforts, the CDC recently released several resources including on making a strong flu vaccine recommendation.
Working in unison with the World Health Organization, the CDC reported that Southern Hemisphere influenza activity during the 2018 season (which can be predictive for subsequent Northern Hemisphere activity) has been relatively low and fairly mild, with influenza A (H1N1)pdm09 viruses predominating in most regions.
Previous Flu Season
Another recent CDC report(www.cdc.gov) looked back on the 2017-18 influenza season and found that during that time, the flu caused 79,400 deaths and 959,000 hospitalizations.
While influenza A (H3N2) viruses predominated through February during the previous flu season, and were predominant overall for the season, influenza B viruses were more commonly reported starting in March 2018.
The CDC noted the season was highly severe with unusually high levels of outpatient influenza-like illness, hospitalizations rates and proportions of pneumonia and influenza-associated deaths.
Resources for Clinicians
Influenza vaccination prevents millions of medical visits, tens of thousands of hospitalizations and thousands of deaths each year, even with vaccine effectiveness estimates around 40 percent to 60 percent, the CDC said.
That's why the agency continues to recommend that health care providers urge their patients to get the flu vaccine, even though patients had been advised to receive it by late October for best coverage. Vaccines can and should continue to be given as requested throughout the influenza season, the CDC said.
To support family physicians' vaccination efforts, the CDC recently released several resources, including one on making a strong recommendation for the flu vaccine.(www.cdc.gov)
This web resource includes a link to the CDC's Advisory Committee on Immunization Practices (ACIP) recommendation for the 2018-19 flu season.(www.cdc.gov)
Additionally, the site explains the SHARE method to making a strong vaccine recommendation:
- Share the reasons why the influenza vaccine is right for the patient.
- Highlight positive experiences.
- Address patient questions.
- Remind patients that flu vaccines protect them and their loved ones.
- Explain the potential costs of getting influenza.
The CDC also offers a Health Care Professional Fight Flu Toolkit(www.cdc.gov) with factsheets, patient fliers and an appointment reminder email template.
The agency lists the types of flu vaccine available and highlights details about their benefits for specific patient populations.
And finally, the CDC created a series of short videos(www.cdc.gov) of health care professionals explaining how they give patients strong recommendations for the flu vaccine.
Currently featured is Carol Hayes, C.N.M., M.N., M.P.H., describing how she recommends the flu vaccine to her nurse-midwife patients and dispels concerns and myths about the shot, including the myth that the vaccine gives patients the flu.
A couple of videos in the series feature AAFP liaison to the ACIP Pamela Rockwell, D.O., of Ann Arbor, Mich., explaining how she recommends the flu vaccine to both older adult patients(www.youtube.com) and pregnant women.(www.youtube.com)
Rockwell says in the videos that she keeps it simple for both groups: "You are due for your flu vaccine today. I recommend it."
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