BOSTON – This year’s severe flu season is on the decline in many parts of the country, including Massachusetts, but it continues to claim lives and send people to hospital.
It is also persevering into being a flu season that could last into May.
According to the latest flu update from the Centers for Disease Control and Prevention, confirmed pediatric deaths from the flu remain on the increase, as do confirmed hospitalizations from the flu.
In Massachusetts, where influenza-like activity remains widespread but at low levels, the number of cumulative laboratory-confirmed cases for the season now stands above 20,000.
Some 603 new confirmed cases were reported by the state health department for the week ending April 6, bringing the total number of laboratory-confirmed flu cases to 20,838 for the current season that began Oct. 1.
Actual number of flu cases in the state over the course of the 2017-2018 season would be much higher as most people with influenza are never tested.
Last year at this time, Massachusetts had 7,173 laboratory-confirmed cases of flu. The number of laboratory-confirmed cases for the comparable week last year was 589.
There was an increase in influenza-associated hospitalizations in the state from 12.5 per 1,000 licensed beds for the week ending March 31 to 14.47 per 1,000 beds for the week ending April 6.
There was also a slight increase in influenza-like activity in the state to 1.95 percent for the week ending April 6. This percentage of visits to reporting outpatient sites for influenza-like symptoms in comparison to overall visits is considered low.
The West Region continues to have the highest number of reported laboratory-confirmed cases on a weekly basis, with 58 Type A and 113 Type B laboratory-confirmed flu cases reported for the week ending April 6. The region also has the highest number of cumulative year-to-date laboratory confirmed cases at 6,276. This includes 4,613 laboratory confirmed cases of Type A, and 1,663 cases of Type B.
The Northeast Region is second with some 5,618 laboratory-confirmed cases of flu to date. This includes 3,592 cases of Type A and 2,026 of Type B.
Influenza activity levels in the Central Region, as well as in Boston, are below baseline levels for their region for the week ending April 6. The highest levels of activity were in the Northeast, Outer Boston and Southeast regions of the state for week the week.
According to the CDC report for March 31, five pediatric deaths were reported to the agency during that week. This puts the cumulative number of such pediatric deaths from the start of this year’s flu season Oct. 1 at 142.
The CDC reported a cumulative rate of 99.9 laboratory-confirmed influenza-associated hospitalizations per 100,000 population as of March 31.
The percent of deaths to overall deaths from pneumonia and flu epidemic was below the epidemic threshold, but not the seasonal baseline level, for the week of March 17, according to the CDC’s latest report.
The CDC also reported that percentage of outpatient visits compared to overall outpatient visits for influenza-like symptoms stood at 2.4 percent for the week ending March 31, just two-tenths of a percentage point above the national baseline level.
Only two states – Alaska and Virginia – experienced high levels of such activity, according to the CDC.
The District of Columbia, Puerto Rico, and 28 states, including Connecticut, Maine, New Hampshire, and Rhode Island, experienced minimal influenza-like illness activity.
The CDC has said that most of the time flu activity peaks between December and February and can last as late as May.
This season, influenza-like illness went above baseline in late November and remains elevated in 39 of 54 regions in the country.
The CDC has displayed by month, from 1982-1983 through 2015-2016 flu seasons, the “peak month of flu activity.” This is the month with the highest percentage of respiratory specimens testing positive for influenza virus infection during that influenza season.