CDC Alert: Severe Influenza Illness Reported

Marcia Frellick


February 01, 2016

The Centers for Disease Control and Prevention (CDC) has received reports of severe influenza illness and some deaths and today issued an alert recommending that physicians quickly treat suspected cases in high-risk patients.

Clinicians are advised to quickly treat suspected influenza in high-risk outpatients, those with progressive disease, and all hospitalized patients with antiviral medications, regardless of negative rapid influenza diagnostic test (RIDT) results and without waiting for results of reverse-transcriptase polymerase chain reaction. RIDTs have a high potential for false-negative results, so treatment should not be withheld on the basis of the test.

High-risk patients include the following:

  • children younger than 2 years of age;

  • adults at least 65 years of age;

  • people with chronic pulmonary (including asthma), cardiovascular (except hypertension alone), renal, hepatic, hematologic (including sickle cell disease), metabolic (including diabetes mellitus), or neurologic and neurodevelopment disorders;

  • people with immunosuppression, including that caused by medications or by HIV;

  • women who are pregnant or postpartum (within 2 weeks of delivery);

  • people younger than age 19 years who are receiving long-term aspirin therapy;

  • American Indians/Alaska Natives;

  • morbidly obese people (ie, body mass index of at least 40); and

  • residents of nursing homes and other long-term care facilities.

Guidelines for influenza antiviral use during the 2015–2016 season are the same as during prior seasons and can be found on the CDC website.

Antiviral treatment should be started as soon as possible after illness onset, ideally within 48 hours. Even after 48 hours, antiviral treatment might still be beneficial in patients with severe, complicated, or progressive illness and in hospitalized patients and in some outpatients.

All patients at least 6 months of age who have not received an influenza vaccine this season should get one, the alert states. There are several options for the 2015–2016 flu season; the CDC does not recommend one influenza vaccine formulation over another.

However, even in vaccinated patients, those with clinical signs and symptoms should receive prompt antiviral treatment.

Since October, the CDC has detected co-circulation of influenza A(H3N2), A(H1N1)pdm09, and influenza B viruses. However, H1N1pdm09 viruses have predominated in recent weeks. The CDC has recently received reports of severe respiratory illness among young to middle-aged adults with H1N1pdm09 infection, some of whom required intensive care unit admission. Deaths have been reported.

Clinicians can also consider antivirals for suspected or confirmed influenza in previously healthy, symptomatic outpatients who are not in the high-risk groups, especially if treatment can be initiated within 48 hours of onset.

Although influenza activity nationally is low compared with this time last season, it is increasing. Some regions have seen high activity, and further increases are expected in the coming weeks, the CDC says.


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