Flu forecast up in the air; It's a slow season so far, but that could change.

Byline: Elizabeth Cooney

Here it comes.

Flu season is about to hit its peak this week - unless we already weathered the worst last week - marking a typical February upswing in cases after several years of curveballs.

But then again, it's too soon to tell.

"Seasonal flu activity was slow to start this year but has increased sharply in recent weeks," Dr. Joe Bresee, chief of the epidemiology branch at the Centers for Disease Control and Prevention, said in a conference call with reporters Feb. 8. "I would caution that if you've been around influenza for a while, it's hard to predict what the season will look like either before or during the season."

Last week, UMass Memorial Medical Center's hospital epidemiologist reported that cases have been climbing since Jan. 28. Twenty cases of influenza have been confirmed through laboratory tests in the most recent reporting period, Dr. Richard T. Ellison III said.

"The last two weeks have been the heaviest weeks so far," he said.

Across town at St. Vincent Hospital, no cases had been confirmed as of early last week, making for an extraordinarily quiet season, infectious disease specialist Dr. Anthony Esposito said.

"At the moment it's just not out there," he said. "That's great news."

Health experts gauge how widespread flu is by counting laboratory-confirmed cases and by sampling in 122 locations across the country. They count the number of people showing up in doctors' offices complaining of flu-like illnesses and then they calculate the proportion of those fevers and respiratory ailments that turn out to be true influenza, based on lab tests. While most people don't seek medical attention, those who do serve as indicators of spread.

Last week New England's rate was 10.8 percent, the lowest in the country, according to regional figures gathered by the CDC.

In recent years, the news around the country wasn't so good. In the winter of 2003-2004, the peak came in December. When all was said and done, the totals were not unusual, but early reports of deaths among children and pregnant women were frightening. Lines for vaccine curled out of doctors' office buildings.

Then in October 2004, a vaccine manufacturing problem stripped almost half the nation's supply out of circulation. Lines grew longer and flu shots were rationed by age and medical condition. That year also saw heightened concern about whether avian flu would mutate into a more deadly form easily passed from human to human. A year after the outbreak of SARS shocked the world with how quickly an air-borne disease can spread from Asia to Canada, the specter of pandemic heightened concern and prompted vaccine research and ways to prepare for a public health challenge not seen since 1918.

That history makes this year seems relatively quiet. Vaccine is plentiful, according to Dr. Alfred DeMaria of the state Department of Public Health.

"We've had about 2.3 million doses in Massachusetts, more vaccine than the state has ever delivered," Dr. DeMaria said last week. "It's much harder to say how much actual vaccine got into people's arms."

Another question is how good a match the vaccine is for this year's strains of flu.

Each spring flu experts try to predict which strains of the virus will prevail, based on activity around the world. Because vaccines are grown in chicken eggs, it takes months to produce the shots that people roll their sleeves up for the following fall.

They've been on the money for 16 out of the last 19 seasons, Dr. Bresee of the CDC said. This year the vaccine was designed to protect against two A strains and one B strain. The vaccine is a good match for the A strain circulating this winter in Massachusetts, Dr. DeMaria said. But Dr. Ellison said half of the UMass Memorial cases have been identified as a B strain known as Brisbane, a new strain of the flu virus that was not included in the vaccine.

Dr. Bresee reminds people that even a less-than-perfectly matched vaccine offers some protection.

"We know from past influenza studies that the vaccine can still protect enough to make illness milder or prevent flu-related complications," Dr. Bresee said.

Complications such as pneumonia can lead to the roughly 36,000 flu-related deaths that occur each year. The elderly, people with chronic illnesses and others with weaker immune system are at increased risk.

Vaccine is still available and a good idea to get before the season winds down in March, Dr. DeMaria said.

And, to use Dr. Esposito's term, there's a "collateral benefit" from measures taken under grimmer circumstances in the past, when shortages of vaccine, fears of pandemic flu and an earlier-than-usual peak punched up influenza's profile.

Hospitals, doctors' offices, schools and other public places are urging people to practice other kinds of protection than vaccinations: hand-washing and respiratory etiquette. For Dr. DeMaria it means two new habits.

"Most of us grew up coughing into our hands in respect for our neighbors," he said. "Now we cough into our sleeves. It took me about a month to convert. I carry alcohol-based gel in my pocket now at all times."

At UMass Memorial, since SARS there have been signs in the waiting rooms for ambulatory and emergency care, asking people to cover their mouths, Dr. Ellison said. People can pick up masks, too, as soon as they register.

Not everybody who thinks they might have the flu needs to see a doctor.

Or drag themselves into work.

"If you have the flu, it's a good time to stay at home and protect your co-workers from illness," Dr. Ellison said.

Protect yourself

Simple steps to protect against flu (or many other illnesses):

Wash your hands often, using soap and water or an alcohol-based hand sanitizer.

Cover your mouth when you cough or sneeze, into a tissue or the inside of your elbow. Throw tissues away and wash your hands.

Don't touch your eyes, nose or mouth. This decreases the chance that you will get the flu virus or other germs into your body, or that you will pass the flu to others.

Clean things that are touched often, such as door or refrigerator handles, computer keyboards/mouse, phones and faucets.

Avoid contact with people who are sick. Avoid unnecessary holding, kissing or sharing food, dishes and glasses with anyone who has a cold or the flu. People with young children, weak immune system or a chronic illness should avoid large crowds, if possible.

Avoid contact with birds when visiting countries that have bird flu.

Source: Massachusetts Department of Public Health

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