Week 3 – CDC Influenza Report

In the third week of the 2016-2017 influenza (flu) season, theCDCreported that mortality rates from pneumonia and the flu have reached epidemic levels.

The FluView includes data on morality rates as well as flu cases reported in the United States through January 21.

Based on mortality surveillance data from the National Center for Health Statistics (NCHS), the CDC found that 7.4% of deaths caused by flu and pneumonia in the United States occurred in the week ending January 7, 2017 (week 1).

The figure was higher than the NCHS Mortality Surveillance System’s “system specific epidemic threshold of 7.3% from week 1 of the flu season.

During week 3 of the season, 3 flu-associated pediatric deaths were reported to the CDC. Two of the deaths were associated with an influenza A (H3) virus and occurred during week 2. One death was associated with an influenza B virus and occurred during week 3.

Thus far, 8 pediatric flu-related deaths have been reported in the current season.

As of January 21, 2017, there were 4317 lab-confirmed flu-associated hospitalization reported, which is up from 2864 cases the week prior. Overall, the flu-associated hospitalization rate was 15.4 per 100,000 population during the flu season. The highest rate of hospitalization was found among adults 65 years and older, followed by adults aged 50 to 64 years, and children aged 0 to 4 years.

Among the 4317 hospitalizations, 4005 were associated with influenza A virus, 275 with influenza B virus, 13 with coinfection of influenza A and B, and 24 with influenza virus that had no determined type.

Nationwide, 3.4% of outpatient provider visits due to influenza-like illness were reported as of week 3. This percentage exceeded the national baseline of 2.2%. According to the CDC, the increase in the percentage of patient visits for influenza-like illness may have been influenced in part by a reduction in routine health care visits during the holidays.

Influenza-like illness activity was highest in New York City, Alabama, Georgia, Kansas, Louisiana, Minnesota, Missouri, New Jersey, Oklahoma, South Carolina, and Tennessee.

Arizona, Arkansas, Colorado, Kentucky, Mississippi, New Mexico, Utah, Virginia, Washington, and Wyoming experienced moderate influenza-like activity, according to the CDC.

The remaining states and Puerto Rico had low to minimal activity. Data for the District of Columbia were insufficient to calculate an influenza-like activity level.

The influenza surveillance report found widespread flu activity in 37 states and Puerto Rico; regional flu activity in Guam and 12 states; local flu activity in Indiana and the District of Columbia; and no activity in the US Virgin Islands.