What’s the Latest with the Flu?

Current Flu Situation

Boy measuring feverFlu activity is elevated in the US with increasing illness anticipated during the coming weeks. Centers for Disease Control and Prevention (CDC) surveillance systems show that nationally, the flu season may be peaking now. To date, 37 children have died from influenza this flu season. That number is expected to rise. It is estimated that 85 percent of the children who die from the flu likely have not been vaccinated.

Antiviral Medications for Treatment of Influenza are an Important Adjunct to Annual Vaccination

The CDC issued a Health Alert Network (HAN) Health Advisory on December 27, 2017, to notify clinicians that influenza A(H3N2) viruses are predominating in the US this season and to provide guidance on treatment. Previously, influenza A(H3N2) virus-predominant influenza seasons have been associated with more hospitalizations and deaths in young children and persons aged 65 years and older compared with other influenza virus strains.

Given this widespread influenza activity, clinicians should consider influenza infection as a highly possible diagnosis in patients with fever, cough and other respiratory symptoms, regardless of age.  People with severe or progressive illness, hospitalized patients, and all high-risk patients with suspected influenza should be treated as soon as possible with antiviral medications. High-risk patients, including children younger than 5 years of age, adults over 65 years of age, pregnant women, and anyone with underlying medical conditions, are predisposed to complications of influenza.

While the total reported national supply of influenza antiviral drugs should be sufficient to meet even high seasonal demand, some manufacturers are reporting delays in filling orders. The CDC is aware of spot shortages of antiviral drugs in some places experiencing high influenza activity. The CDC is working with manufacturers to address any existing gaps in the market. Clinicians can consider including mention of the potential shortages when writing a prescription so families are aware they may need to call a pharmacy in advance.

See the American Academy of Pediatrics (AAP) policy “Recommendations for Prevention and Control of Influenza in Children, 2017 – 2018” for updated recommendations on the routine use of seasonal influenza vaccines and antiviral medications for the prevention and treatment of influenza in children.

Annual Flu Vaccination Continues to be the Best Way to Prevent Influenza.

Even though we are already in the flu season, annual vaccination remains the best available preventive measure against influenza. While the effectiveness of flu vaccines can vary from season to season, recent studies show vaccine reduces the impact of flu by about 30% to 60% among the overall population during seasons when most circulating flu viruses match well with those viruses used to produce the vaccine that season. The CDC monitors circulating viruses throughout the year and provides new and updated information about their similarity with the flu vaccine viruses as it becomes available.

Influenza surveillance data is published weekly in FluView and summarized at intervals in the Morbidity and Mortality Weekly Report (MMWR). Vaccine effectiveness estimates are also provided when available. In previous seasons, vaccine effectiveness against H3N2 viruses has been around 30%, whereas effectiveness against H1N1 viruses has been about 50% and effectiveness against influenza B viruses has been around 60%. Similar vaccine effectiveness is expected this year. For more information on the effectiveness of flu vaccines, see Frequently Asked Flu Questions 2017-2018 Influenza Season on the CDC website.

The influenza epidemic is likely to continue for several more weeks. Therefore, it is important to continue to recommend annual influenza vaccination to everyone 6 months of age and older, particularly contacts of children too young to be vaccinated and of children with high-risk underlying conditions. In addition, please ensure that children 6 months through 8 years, who need 2 doses to be adequately protected, receive both doses 4 weeks apart. It is especially important to identify and vaccinate infants who turned 6 months old since the beginning of this year’s flu season. See the AAP News article, “CDC urges vaccination for flu as hospitalizations rise“, for additional information.

Many Strategies Exist to Reach Families

Informing families about the importance of influenza prevention and control through various messaging strategies can make a real difference. The recent CDC Public Health Matters Blog outlines how to talk to friends, family, and patients about flu vaccines. Pediatricians can share a link to this blog with families and encourage them to take important steps to protect themselves from influenza. Also consider sharing the Vaccine Locator. This tool identifies the locations where influenza vaccine is available in a particular area. Does your practice have a Web site or a social media outlet? If not, consider creating one to easily share updates and reminders with families throughout flu season.

Archived Webinar: What’s New for the 2017-2018 Flu Season: Recommendations for Children

In November 2017, the AAP collaborated with CDC to conduct a webinar titled “What’s New for the 2017-2018 Flu Season: Recommendations for Children“. During this webinar, subject matter experts from the AAP and CDC highlighted valuable information about this year’s flu season and discussed strategies primary care providers and medical subspecialists could use to improve flu prevention and control in children. The archived version of the webinar, a transcript, and presentation materials/resources can be viewed online.

Additional Information

See the AAP Red Book Online Influenza Resource page, CDC FluView, or the CDC Digital Media Toolkit: 2017-18 Flu Season. Each “What’s the Latest with the Flu” messages will be archived. Also see the AAP Seasonal Flu Collection.