The Flu: What You Need to Know
The flu has arrived with a vengeance. Massachusetts and national statistics confirm this is a bad flu season. It is not the worst year in recent memory—for example, the pace in 2014-5 was faster—but it’s bad enough.
Let's look at some facts you need to know.
What are the numbers? Here in Massachusetts, the week ending Jan. 12 showed a slight dip in cases—but it is too soon to know whether this is a trend. Laboratory-confirmed cases in the state are running at three times the rate they were last year. About 80 percent of confirmed cases are with influenza A, 20 percent with B. Ninety percent of the A’s, when tested, have been H3N2 as expected; 10 percent have been H1N1. Nationally, statistics are about where they usually are at this time of year. Flu is widespread in 49 states, including Massachusetts. Twenty children in the U.S. have died of the flu so far this year. Flu hospitalizations are up, especially among the elderly. Bottom line: Shaping up as a bad year.
But numbers are not everything! Last year, 101 kids in the U.S. died of the flu; the numbers have ranged yearly from a low of 37 to a high of 171. Each of these is a terrible tragedy. The flu is not a minor illness. Yes—the chronically ill, the elderly and the young are disproportionally affected—but healthy children and young adults can be struck down and die. Local newspapers have featured individual deaths, for example a young mother in Needham.
What about the flu shot? Is it as bad as some think it is this year? Yes and no. Effectiveness in Australia was only about 10 percent. But this is not Australia. First of all, immunization rates there are not as good as they are in the U.S. Here in the U.S., early estimates are about 30 percent efficacy against H3N2, much better against other strains. In an interview on Jan. 12, Dr. Jan Dernigan, Director of the Influenza Branch at CDC, stated, “Our information so far suggests that vaccine effectiveness against the predominant H3 viruses will probably be somewhere around what we saw in the 2016-2017 season, which was in the 30 percent range. While this is better than the 10% that has been reported from Australia in one study, it still leaves a lot to be desired and we’re very well aware we need to have better flu vaccines.” Yes, we need better vaccines. But what we have, we have.
A study last year of 358 children who died of flu between 2010 and 2016 showed 65 percent efficacy in preventing death from flu in children. In other words, a child who received a flu shot had a chance of dying that was reduced by 2/3 compared with an unvaccinated child. In that same study, four out of five of the children who died had not received a flu shot.
What about Tamiflu? While the drug is not perfect, there has been no resistance found so far in the test tube among the circulating flu strains this year. The Massachusetts Department of Public Health and CDC specifically recommended its use in high-risk individuals who are suspected of having flu, emphasizing treatment should be based on symptoms and not rely on testing. Treatment is recommended for all individuals hospitalized with flu. In such high-risk or hospitalized patients, while it is best to start treatment within 48 hours of symptom onset, it is probably worthwhile to start later. They also suggest that treatment can be considered for anyone with the flu—even healthy folks—if it is started within 48 hours of onset of symptoms.
This is shaping up as a bad flu season. There have been worse—but it’s still bad. Many hospitalizations are occurring, and people have died and will die. Some of these deaths are in perfectly healthy adults and children. The vaccine is not perfect, but even if it prevents 30 percent of cases of the prevalent H3N2 strain, that’s better than zero percent without the vaccine. And it’s much better against the other strains, which usually account for about 20% of cases. The flu season can stretch out to May or even later, so it still pays to get the shot if you have not done so already.
Flu is no joke.
Source: Dr. Mark Drapkin, Newton-Wellesley Hospital