 If
you're wondering what happened to the flu, you're
not alone.
It's
curiously late, like our knee-deep snow, here and
across the nation.
This
is the slowest start in the nation's flu season
in 29 years. And while the number of cases began
to pick up this month, it's not entirely clear what
that means.
Influenza
generally peaks in February and then peters out
in March and April, yet it also varies in its timing
and duration. The season has been known to start
as early as October and last as late as May, according
to the federal Centers for Disease Control and Prevention.
"We've
been fortunate that the onset of flu has been delayed,
but it's upon us now," said Dr. Gale R. Burstein,
health commissioner of Erie County.
"It's
difficult to say how things will go. The flu is
very unpredictable," said Dr. Howard S. Faden,
chairman of infection control and director of virology
at Women & Children's Hospital in Buffalo.
The
pediatric hospital oversees one of two laboratories
in the region — Erie County operates the other
— that test for the presence of flu viruses
as part of the U.S. influenza surveillance system.
The
hospital's lab normally has confirmed dozens of
positive cases by this time of year, a sign that
the virus is widespread in the community. As of
last week, it had identified none. The Erie County
lab had confirmed only three positive samples sent
in by doctors and other hospitals, with the first
testing positive in late December.
People
are suffering from respiratory illnesses, such as
the common cold. Until recently, however, it probably
wasn't the flu.
There
were 132 million doses of vaccine distributed for
this season, and mass immunization programs have
ended in the Buffalo Niagara region. But public
health officials continue to recommend that unvaccinated
individuals, especially those at risk of complications
from the flu, get a shot from a doctor or health
center as a way to protect themselves and to prevent
spreading the disease.
Complications
of flu can include bacterial pneumonia, ear infections
and worsening of such chronic medical conditions
as congestive heart failure.
Over
31 seasons between 1976 and 2007, estimates of flu-associated
deaths in the United States ranged from about 3,000
to 49,000 people, according to the CDC. An estimated
90 percent of the deaths occur in people 65 and
older, but young people are not immune.
Death
of a 15-year-old
What happened to Chelsea Oliver offers a cautionary
tale.
The
Amherst High School sophomore came down with flulike
symptoms Oct. 25, 2009, and, after visiting her
doctor, was treated as though she had the flu.
Things
only got worse, with Chelsea soon complaining that
she couldn't breathe. She was admitted into the
intensive-care unit at Women & Children's Hospital,
where she was diagnosed with pneumonia and sepsis,
an inflection of the bloodstream.
The
hospital staff intubated Chelsea and placed her
on ECMO, or extracorporeal membrane oxygenation.
ECMO is similar to a heart-lung bypass machine and
is used when patients fail to respond to a respirator.
Under ECMO, the patient's blood receives oxygen
from an artificial lung.
Her
condition fluctuated over the next few days, and
then rapidly deteriorated. She died Nov. 1, less
than a week before the first signs of sickness.
She was 15.
"It's
still hard to talk about it. Everying that happened
didn't feel like reality," said Cheryl Craft,
her mother. "She had been perfectly healthy.
Then she walked into the hospital with me, and that
is the last time we spoke to each other."
That
season featured a worrisome new strain of influenza
called H1N1, also known as swine flu. It turns out
that is what Chelsea had, in addition to MRSA, or
methicillin-resistant staphylococcus aureus, a bacterium
resistant to common antibiotics.
Several
weeks after her death, supplies of the H1N1 flu
shot arrived after delays nationwide caused by several
factors, including production problems.
"I
still wonder if her life would have been saved had
the vaccine arrived on time," said Craft, patient
manager at the University at Buffalo School of Dental
Medicine.
Since
then, Craft has gone on to become an advocate for
flu immunization. She joined the Western New York
Pediatric Adolescent Coalition, a group committed
to increasing immunization rates.
Last
fall, she also established the Chelsea Oliver Foundation
in honor of her daughter. Its goals include providing
scholarships to high school students interested
in the health care field.
"I
don't want Chelsea's story to die," Craft said.
It's
not possible to count every individual with influenza.
Instead, flu trackers monitor such indicators as
influenzalike illness reported by emergency rooms
and outpatient centers, deaths from influenza and
cases confirmed by laboratories that test nasal
secretion specimens from patients.
Vaccinations
advised
Nationally, the number of respiratory samples testing
positive for the virus remained below 10 percent
until early February. This happened only once before
over the last 29 years — in 1987-1988 —
according to the CDC. By Feb. 18, the percentage
of specimens testing positive for influenza in the
United States had risen to 14.4 percent.
The
moment when laboratory-confirmed influenza cases
rise above the 10 percent level is a key measure
public health officials use to indicate the start
of flu season.
"The
increases we are seeing in the number of respiratory
samples testing positive for flu should forecast
increases in other flu activity indicators in the
coming weeks," cqLyn Finelli, chief of domestic
surveillance for CDC's Influenza Division, said
in a statement.
The
CDC continues to recommend that individuals 6 months
and older get vaccinated. It takes about two weeks
after a shot for the body's immune system to develop
antibodies that provide protection against the influenza
viruses in the vaccine. Antibodies are proteins
that neutralize such harmful substances as bacteria
and viruses.
The
viruses that cause influenza constantly mutate,
changing year to year. That requires manufacturers
to regularly update the vaccine based on predictions
by experts of what strains will predominate.
As
a result, flu vaccine does not ensure total protection.
Its effectiveness depends in part on the match between
the viruses in the vaccine and the viruses circulating
in the community. So far, the majority of viruses
identified this season appear well matched to the
strains in the 2011-12 vaccine.
A
perplexing question
A vaccination is considered the best way to prevent
the flu, but many people don't get it. An estimated
43 percent of Americans 6 months and older were
immunized for the 2010-11 flu season, far short
of a target of 80 percent in the nation's disease-prevention
plan, Healthy People 2020.
Why
don't more people get immunized and take other simple
steps to prevent the flu, such as regularly washing
hands? That's a question that has perplexed public
health officials.
"There
is no magic answer," said Marc T. Kiviniemi,
a social and behavioral scientist at UB who published
a report last year on the willingness of the public
to engage in influenza precautions.
His
survey in BMC Public Health found that despite intense
flu education efforts, as well as media attention,
many people don't appear to know the most common
actions to prevent the disease, such as avoiding
sick people and coughing into your sleeve.
In
addition, there is great variation in people's willingness
to engage in preventive measures, including immunization.
"The
ideal would be to engage in behaviors without thinking
about them, like brushing your teeth," Kiviniemi
said. "But the challenge with the flu is that
a lot of the preventive behaviors require you to
do things when there is no health risk prevalent."
hdavis@buffnews.com
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