Flu Strain, Vaccine Not A Good Match This Season

By John Voket

Across the country and here in the region, the flu season is getting worse, and health officials say it is partly because the flu vaccine does not protect against most of the spreading flu bugs.

Dr Z. Michael Taweh, founder of Kevin’s Community Center here in Newtown, reported this week the only two clinically diagnosed influenza patients he has seen in his private practice both received the flu shot offered this season.

“That leads me to believe the news of a resistant strain is legitimate,” Dr Taweh said in-between seeing patients Wednesday at the Newtown-based public health clinic.

The flu shot is a good match for only about 40 percent of this year’s flu viruses, officials at the US Centers for Disease Control and Prevention said in a statement issued February 15.

The situation has even deteriorated since the week before, when the CDC reported this year’s vaccine was protective against roughly half the circulating strains. In good years, the vaccine can fend off 70 to 90 percent of flu bugs.

Infections from an unexpected strain have been booming, and now are the main agent behind most of the nation’s lab-confirmed flu cases, said Dr Joe Bresee, the CDC’s chief of influenza epidemiology.

It is too soon to know whether this will prove to be a bad flu season overall, but it is fair to say a lot of people are suffering at the moment. “Every area of the country is experiencing lots of flu right now,” Dr Bresee said.

This week, 44 states reported widespread flu activity, up from 31 last week. The number children who have died from the flu nationally has risen to ten since the flu season’s official September 30 start.

A high level of influenza activity was observed in Connecticut during the 19th week of the 2007-2008 influenza season beginning February 11. A total of 804 laboratory confirmed test reports have been received to date, with 490 identified as type A and 196 as type B influenza, and 118 as unknown type, according to the Connecticut Department of Public Health.

Those numbers are not considered alarming. Early February is the time of year when flu cases tend to peak. The ten pediatric deaths, though tragic, are about the same number as was reported at this time in the last two flu seasons, Dr Bresee said.

The biggest surprise at the CDC has been how poorly the vaccine has performed.

Each winter, experts try to predict which strains of flu will circulate so they can develop an appropriate vaccine for the following season. They choose three strains — two from the Type A family of influenza, and one from Type B.

Usually, the guesswork is pretty good: The vaccines have been a good match in 16 of the last 19 flu seasons, Dr Bresee has said.

But the vaccine’s Type B component turned out not to be a good match for the B virus that has been most common this winter. And one of the Type A components turned out to be poorly suited for the Type A H3N2/Brisbane-like strain that now accounts for the largest portion of lab-confirmed cases.

Over the years, the H3N2 flu has tended to cause more deaths, Dr Bresee said.

This week, the World Health Organization took the unusual step of recommending that next season’s flu vaccine have a completely different makeup from this year’s. The US Food and Drug Administration is expected to make its decision about the US vaccine next week.

H3N2 strains are treatable by Tamiflu and other antiviral drugs, but the other, H1N1 Type A strains are more resistant. Of all flu samples tested this year, 4.6 percent have been resistant to antiviral medications. That is up from fewer than one percent last year.

“This represents a real increase in resistance,” Dr Bresee said.

At KCC and in his practice, Dr Taweh said hundreds of his patients have been inoculated, which he believes accounts for the tiny number of clinically diagnosed patients. He is, however, seeing a rash of patients presenting with “flulike,” symptoms.

“We are seeing plenty of patients we have diagnosed with a respiratory virus, para influenza and the rhino virus,” he said, “but no other clinically diagnosed cases of the actual influenza.”

Increased numbers of reports have been logged all eight counties in Connecticut, the state DPH is reporting. And the increased level of flu activity in all eight counties resulted in a the department’s continuation of its national flu activity classification as “widespread” during the week ending February 9.

New Hampshire joined Massachusetts, New Jersey, New York, Pennsylvania, Vermont, and most of the country in reporting “widespread” activity. As of February 15, only six states nationally were reporting less than widespread activity, including Maine, which recently increased from “local” activity, joining Rhode Island in reporting “regional” activity.

Approximately 50–70 doses of this year’s flu shot were distributed through the Newtown Health District to KCC, which inoculated patients and Newtown municipal employees who requested the vaccine. The district also supplemented flu vaccines to the local VNA Association for patients requesting a shot who could not afford to pay, according to Health District Director Donna Culbert.

“We wouldn’t want anyone walking out of a flu shot clinic not getting the vaccine because of an inability to pay,” she said.

Dr Taweh warned Newtown residents to continue their precautionary practices, washing hands and restricting contact with those who may be sick. He said it is not unusual for the flu season to last well into April and even early to mid-May if the weather stays colder.

(Associated Press reporters were used in this story.)