Sweating the Swine Flu

How many cases of swine flu are in the Knoxville area? Who knows?

The Centers for Disease Control have recommended against a Real Time-Polymerase Chain Reaction, or specific swine flu test, for all but the most vulnerable—pregnant women, people who are hospitalized, those with health conditions that might lead to severe complications—and that rules out hard and fast figures. At the same time, public health officials are urging anyone with symptoms to go into isolation, confirmed case or no. "A person should stay home if they have fever and any other symptom—cough, headache, runny nose, sore throat, body aches," says Ranee Randby, public health community relations director for the Knox County Health Department. "Stay away from others until you have been fever-free without the use of medication for 24 hours."

Would the real swine flu please stand up? Is it life-threatening, worthy of extreme caution and maybe a touch of panic? Or so inconsequential that the state has few statistics on its spread, and you don't even need to verify whether you have it?

"I think there is certainly quite a bit of hype," says Dr. Mark Rasnake, program director for internal medicine residency at the University of Tennessee, who is a specialist in infectious diseases. "It doesn't look like it's going to be a devastating pandemic, nothing like the 1918 influenza."

At the same time, the health community forecasts mass numbers of swine flu cases. "We'll probably see at some point 30 percent of the citizens in Knoxville catch this strain of flu," says Rasnake. That number will involve a small percentage of fatal cases that make avoiding the spread of H1N1 crucial. Countering both hysteria and lethal complacency is a matter of understanding that swine flu is new and very different from seasonal flu, presenting different risks. Below, Randby and Rasnake debunk the most misleading myths making the rounds in Knoxville:

Myth: There is a lot of flu going around that isn't swine flu.

"If you hear of any case of influenza that's occurred since this spring, virtually 99 percent of that is the swine flu," says Rasnake. Which is not to say these are "confirmed" cases, says Rasnake.

"The PCR test is expensive. When you look at the possibility of millions of cases this year nationwide, it's just not logistically possible or necessary to test all of those people. Only a tiny percentage are being tested for the swine flu. Most people are getting a rapid flu-screen test, which takes just 20-30 minutes for results, versus a week for the results of the PCR test for H1N1. But the rapid test just screens for the presence of generic flu viruses. It's not a specific swine flu test."

Myth: Senior citizens are the most vulnerable to swine flu.

Ordinary seasonal flu, yes. Swine flu, no. "H1N1 tends to sicken young people between the ages of 6 and 25 more than any other group," says Randby. CDC documents indicate that "adults older than 64 years do not yet appear to be at increased risk of 2009 H1N1-related complications thus far. CDC laboratory studies have shown that no children and very few adults younger than 60 years old have existing antibody to 2009 H1N1 flu virus; however, about one-third of adults older than 60 may have antibodies against this virus." Those under 65, though, make up 85 percent of Knoxville's population.

Myth: This is a fairly ordinary flu season in Knoxville.

The Southeast in general got flu—mostly swine flu—earlier than the rest of the country. "Flu season started very early this year, beginning in summer," says Rasnake. Knoxville in particular has had an even heavier late summer/early fall outbreak because being a large university town "fans the flames of the flu activity," and UT started back the second full week of August. In one way, the early onslaught is good, because the close quarters inspired by cold winter temperatures and rain can hasten the spread of flu. On the other hand, it means the vaccine will come too late for many.

Myth: Swine flu is particularly lethal.

In fact, the virus seems to be slightly less lethal than most flus. "We've also seen less hospitalization than we have with seasonal flu," says Rasnake. But here's the issue: The majority of the population has no pre-existing immunity to swine flu.

"Since there is no immunity, more people will get sick and, as a result, more could die," says Randby. In its initial pandemic planning of April 2009, the state health department estimated the percentage of lethal cases from a flu at between .2 and 2 percent. Even if the percentage is much lower, when you consider a projected 30 percent of Knoxville's around 175,000 population could get swine flu, the deaths could still be in the dozens.

Myth: Because the symptoms are relatively mild for a flu, it's okay to go around others when you have symptoms of the swine flu.

The swine flu is far too contagious for that—very few people under 65 have any pre-existing immunity to it at all. "The CDC has recommended if you have a fever and flu-like symptoms, then stay home at least 24 hours after fever is gone without using medication to keep it down," says Rasnake. "From what I've heard, people are very reluctant to skip work days. And I think with this being a relatively mild flu, a lot of people are able to still go to work—I just don't think people are staying home. The big danger is they don't know if their coworker has some underlying immune system problem or lung disease, and they think they are doing good for the company by showing up at work sick. If they infect someone with these problems they can take what's mild for them and cause a potentially lethal infection."

Myth: The vaccine will take care of the problem right away.

The first H1N1 vaccines should reach this area in about three weeks—around mid-October—and the highest-risk individuals, such as children under age 6, pregnant women, people with lung disease, and health-care workers will be top priority. Deliveries will continue until everyone is inoculated, says Randby, and there will be no cost for the vaccine, though some providers may charge a small administration fee to cover overhead. People 10 years and older will require one dose. The pediatric vaccine is still in clinical trials, so the dosage is unknown for now, but it's likely to require two doses according to information released by the National Institutes of Health on Monday. "I am fairly confident that it will be an effective vaccine," says Rasnake. "But it will be too late for quite a lot of people in Knoxville because the flu hit here so early. A substantial part of the city will already be exposed to this virus before we even start to get the first supplies."