Seasonal Flu Activity Continues to Climb in United States

37 States Report Cases Are Widespread

February 01, 2017 04:01 pm News Staff

As February begins, influenza activity in the United States continues to increase. According to the CDC's FluView report( for the week ending Jan. 21, the number of states reporting widespread flu activity during the 2016-2017 season jumped to 37 from 29 the previous week.  

Three flu-associated pediatric deaths were reported to the agency the same week, bringing the total number of pediatric deaths to eight for the season. Two of those deaths were associated with an influenza A (H3) virus and occurred during the week ending Jan. 14. The third death was related to an influenza B virus and occurred during the week ending Jan. 21.

Story highlights
  • According to the CDC's FluView report for the week ending Jan. 21, 37 states have reported widespread flu activity.
  • Three additional flu-associated pediatric deaths were reported the same week, bringing the total to eight for the 2016-2017 flu season.
  • The percentage of patients seeing their physician for influenza-like illness has been at or above the national baseline for six consecutive weeks so far this season, with influenza A (H3) viruses predominating.

The percentage of patients seeing their physician for influenza-like illness (ILI) has been at or above the national baseline for six consecutive weeks so far this season, with influenza A (H3) viruses predominantly responsible for those visits. During the week ending Jan. 21, 3.4 percent of patients saw a health care professional for ILI, compared with the national baseline level of 2.2 percent, and all regions reported ILI at or above their region-specific baseline levels.

Key Flu Indicators

According to CDC FluView's ILI state activity indicator map(, New York City and 10 states (Alabama, Georgia, Kansas, Louisiana, Minnesota, Missouri, New Jersey, Oklahoma, South Carolina and Tennessee) experienced high ILI activity.  

Another 10 states (Arizona, Arkansas, Colorado, Kentucky, Mississippi, New Mexico, Utah, Virginia, Washington and Wyoming) experienced moderate ILI activity.

As for hospitalizations related to flu, the CDC reported that since Oct. 1, 2016, 4,317 laboratory-confirmed influenza-associated hospitalizations have been reported.

Puerto Rico and 17 states (Alaska, California, Florida, Hawaii, Idaho, Illinois, Iowa, Maryland, Michigan, Nebraska, Nevada, New York, North Carolina, Oregon, Pennsylvania, South Dakota and Texas) experienced low ILI activity.  

Concerns About Avian Flu Mount

According to the World Health Organization (WHO)( as of Jan. 16, 918 laboratory-confirmed cases of human infection with avian influenza A (H7N9) viruses, including 359 deaths, have been reported to the agency since 2013.

The WHO said about 40 countries have reported outbreaks of avian influenza in poultry and wild birds since November 2016.

According to the CDC, it's rare for people to be infected with bird flu viruses, but it is possible if a patient touches an infected animal or surface and then touches his or her eyes, nose or mouth. There also is a possibility of becoming infected by inhaling the virus.

Initial signs and symptoms of infection include fever, cough, sore throat, runny or stuffy nose, muscle or body aches, fatigue, headaches, conjunctivitis and difficulty breathing. The infection can cause very serious illness, including severe pneumonia, acute respiratory distress syndrome, septic shock and multi-organ failure leading to death.

"This translates to a cumulative overall rate of 15.4 hospitalizations per 100,000 people in the United States," the CDC FluView summary stated. "This is higher than the hospitalization rate at this time (2.5 per 100,000) last season, when influenza A (H1N1)pdm09 viruses predominated."

The agency said the highest hospitalization rates by far (72.2 per 100,000) are among patients ages 65 and older. Adults 50-64 are being hospitalized at a rate of 15.2 per 100,000, and the hospitalization rate among children younger than 5 years is 8.4 per 100,000. The CDC added that during most typical flu seasons, children younger than age 5 and adults ages 65 and older have the highest hospitalization rates.

It should be noted that these hospitalization data are collected from only 13 states, represent about 9 percent of the U.S. population and don't reflect the actual number of influenza-associated hospitalizations in the United States.

Additionally, the CDC said the percentage of deaths attributed to pneumonia and influenza was 7.4 percent for the week ending Jan. 7. "This percentage is above the epidemic threshold of 7.3 percent for week 1 in the National Center for Health Statistics Mortality Surveillance System," the report noted.

Flu Shot Reminder

CDC officials continue to recommend that everyone 6 months and older receive an annual flu vaccination. It's still not too late to get a flu shot this season, said the agency in the report, and physicians should recommend that all patients who have not yet received the shot do so now.

For the 2016-2017 season, the CDC recommends use of the inactivated influenza vaccine and the recombinant influenza vaccine. The agency reminds physicians not to use the nasal spray flu vaccine (live attenuated influenza vaccine) this season and offers a handout( to explain why to patients.

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