Like much of the U.S., flu cases on the rise in New Hampshire

Monitor staff
Thursday, February 15, 2018

Cases of influenza continue to rise in New Hampshire to a point not seen since the 2009 pandemic of the H1N1 virus, echoing a pattern seen throughout most of the country.

As of early February, according to data from the state, 24 people – all adults – had died due to flu-related illness, which is roughly in line with the average toll taken by flu in those years when a particular strain of the disease, known as H3N2, dominates.

“With H3N2, we tend to see more hospitalization and more deaths,” said Dr. Benjamin Chan, the state epidemiologist. “In past years, that strain has produced 45 to 50 deaths during flu season.”

Several types of flu viruses circulate in the U.S. each year, and part of the complications of making the vaccine is guessing which of the many strains will be prevalent. There is no universal vaccine that protects against all strains of the flu.

On Thursday, the national Centers for Disease Control and Prevention released an annual report on the effectiveness of this year’s flu vaccine, putting it at 36 percent for all ages.

“That means it has reduced the risk of getting sick and going to the doctor’s office by about a third,” Chan said.

Chan said it is expected that influenza B and H1N1 strains will make up a larger part of the mix in the coming weeks, since that is the usual pattern over the course of the flu season.

As a result, he said, it can still be helpful to get a flu vaccination.

Vaccinations for influenza, along with a number of other diseases, are free for people under age 18 in New Hampshire. Vaccines are particularly recommended for the elderly, who are more susceptible to the disease.

The state’s Immunization Program committed to purchase 166,000 doses of influenza vaccine this year. As of Feb. 14, more than 132,000 doses have been distributed and more than 110,000 doses have been reported as administered.

These figures are similar to the past several years, according to Department of Health Human Services.

Influenza is not a directly reportable disease, so its prevalence in New Hampshire is estimated from doctors’ reports of patients with influenza-like symptoms and emergency room cases of respiratory illness.

In 2009, H1N1 influenza spread around the world for the first time, so few people had a natural immunity to it and vaccines were not prepared. An academic study estimated that at least 150,000 people worldwide, and perhaps as many as 575,000, died from flu that year.

Health officials say that frequent hand washing and protecting other people from coughs and sneezes remain the most effective ways to not spread the disease, along with having sick people stay home from work or school until the symptoms have passed.

“There are still many weeks of the flu season to go,” Chan said.

(David Brooks can be reached at 369-3313 or dbrooks@cmonitor.com or on Twitter @GraniteGeek.)