H1N1 “swine” flu epidemic could race ahead before vaccine arrives warns state epidemiologist

Photo Credit: CDC

Individuals, businesses and other organizations need to take steps now to reduce the spread of influenza because it appears the H1N1 flu epidemic will be well underway before the newly developed vaccine becomes available, Washington State Epidemiologist Dr. Tony Marfin told a Pandemic Influenza Summit held in Seattle earlier this week.

To date, the H1N1 “swine” flu virus has not proved to be as virulent as health officials feared when it first appeared last spring with the vast majority of people recovering at home.

But new strain has caused deaths, and a large epidemic of even mild illness could cause widespread disruptions of both schools, businesses and other organizations as large numbers of students, workers and staff fall ill, Dr. Marfin said.

What’s different about the H1N1 flu is, first, that it spreads so much more easily than the flu we’ve seen in recent years so it is likely that a great many more people will fall ill this flu season, Dr. Marfin said.

In a typical year, about 5 percent to 20 percent of the population will come down with flu, but because the new H1N1 is so contagious 30 percent to 50 percent of the population is expected to become infected this flu season, Marfin said.

It this proves to be the case, even though it is less virulent, the new H1N1 could still kill a substantial number of people, because causes so many more infections.

According to a recent assessment of the President’s Council of Advisors on Science and Technology , 30,000 to 90,000 Americans could die from the new flu, Marfin said.

Photo Credit: CDC

That compares to 36,000 flu-related deaths seen on average each year due to seasonal flu.

Second, unlike typical flu, the new H1N1 virus also seems to hit the young and middle-aged hardest, Marfin said.

Usually, the very young and elderly are most susceptible to serious complications from the flu, Marfin said.

Typically, more than 90 percent of flu-related deaths occur among people aged 65 years or older.

But the new H1N1 is hitting younger people, those age 5 to 64, hardest.

In fact, it’s predicted that more than 90 percent of those who die of H1N1 infections will be under age 65, Marfin said.

So far that seems to be the pattern in Washington state, Marfin said. Since May health officials have been tracking serious H1N1 infections—those that cause hospitalizations or death, and as of end of last month, August, they had identified 170 serious cases:156 that led to hospitalization and 14 that resulted in death.

Of these, patients between the ages of 5 and 64 made up 72 percent of those hospitalized—and 93 percent of those who died.

“This is very, very unusual,” Mafin said.

Older people, he said, may be protected because they could have been exposed to a similar strain of H1N1 that circulated in the 1950s.

Their immune systems are therefore primed and ready to react swiftly to the new H1N1 infection.

But those born after the 50s have never seen a virus like the new H1N1, and so their immune systems are less prepared to defend against it, Marfin said.

“This is a disease of young people,” he said.

And an epidemic that hits people between age 5 and 65 hardest will have a very different impact on society that one that hits the elderly hardest, Marfin said.

“Think about this age group,” Marfin said. “It’s your parents, students and workforce.”

There is now vaccine agains H1N1, and early testing suggests that a single dose may be enough to induce protection, but the vaccine will not become available until mid-October and then in limited amounts.

The current plan is to give priority to people at high risk of complications—such as pregnant women and those with some chronic illnesses—and those who will be needed to contend with the epidemic, such as healthcare providers and emergency workers.

Eventually enough vaccine will become available for everyone who wants it, Marfin said, but still not enough will arrive in time to halt the epidemic.

Indeed, unless people take steps to prevent the spread of virus by washing their hands frequently, covering their coughs and staying home when they are ill, the epidemic could have peaked before most people have been vaccinated.

Then there’s the strains of typical seasonal flu, which tends to arrive later in the year.

“We have the possibility of having three circulating influenza A viruses. It’s never happened before—this is a brand new situation,” Marfin said.

These strains could cause their own flu epidemic, though it is not yet clear how virulent or contagious these viruses will be this year, Marfin said.

So far most influenza cases both in the U.S. and abroad appears to be predominantly due to the new H1N1, he said.

To reduce the impact of influenza this year people need to takes steps now to slow the spread of both seasonal and the new H1N1 viruses, Marfin said.

Individuals should get the seasonal influenza vaccine, which is available now, Marfin, and the new H1N1 vaccine when it becomes available.

They should also adopt simple measures such as frequent hand washing, covering their coughs and staying home when sick all of which can reduce the risk of spreading influenza, Marfin.

In addition, businesses and government agencies need to take steps that will allow workers to stay home if they fall ill and to take time off to take care of sick children who are sent home from school and to set up ways people can work from home, Marfin said.

People need to have a plan, Marfin said, “The vaccine is not going to arrive in time to stop widespread transmission of this virus.”

To learn more:

• Visit the Washington State Department of Health’s H1N1 (Swine Flu) information page.
• Visit the federal governments Flu.gov Web page.
• Visit the U.S. Centers for Disease Control (CDC) and Prevention’s H1N1 information page, which has links to guidance documents for businesses and employers, colleges and universities, child and day care centers, pregnant women and other specific groups.
• For Schools read: “Preparing Schools for H1N1 Flu” prepared by the Office of Superintendent of Public Instruction.
• Read Seattle Times health reporter Kyung Song’s article on the summit: Swine flu could strike a third of state residents this fall, experts predict.

Tags: H1N1, Influenza, Swine Flu

Category: Infections, Influenza