The case count in the ongoing outbreak of new swine flu has jumped from 12 cases last week to at least 145 cases, the CDC announced today.

Even while the CDC was making the announcement, Indiana health officials reported seven new cases. That brings the total to 152 cases -- and counting.

Dubbed H3N2 variant or H3N2v, the virus causing the outbreak is a swine flu bug that more easily infects humans than the swine flu viruses previously circulating in pigs. All cases this year are in people who had direct contact with live pigs. You cannot get the virus from eating pork.

When the virus first appeared last year, there were a few cases of very limited human-to-human spread. There's been no person-to-person spread so far this year, Joseph Bresee, MD, of the CDC's Influenza Division, today said at a news conference.

"There is no sign of an increase in overall flu activity. This is not a pandemic situation," Bresee said.

Even so, case counts are rising in Indiana, now reporting 120, and in Ohio, now reporting 30. Since the outbreaks began, there have also been single cases in Hawaii and in Illinois. Bresee said the CDC would not be surprised to see outbreaks in other states.

"We expect to see more cases next week," he said.

Nine out of 10 cases are in children. That could be because children have been exposed to fewer flu bugs and vaccinated less often than adults. Or it could be because nearly all pig exposures have come at state, county, and local agricultural fairs, where children typically show off the animals they have raised.

Typically, only six or seven people a year come down with swine flu from pigs. This year may be different because H3N2v has picked a gene from the 2009 pandemic flu virus that may allow it to better infect humans.

The seasonal flu vaccine does not protect against H3N2v swine flu. Fortunately, the new swine flu is no more dangerous than typical seasonal flu. So far this year there have been only two hospitalizations and no deaths from the new flu bug.

Thousands of state and county fairs are ongoing. At this point, the CDC's plan to stop the outbreak is to warn fairgoers to avoid pig contact. The official CDC advice:

• Wash your hands frequently with soap and running water before and after exposure to animals.
• Never eat, drink, or put things in your mouth in animal areas.
• Children younger than 5, people 65 and older, pregnant women, and people with certain chronic medical conditions (like asthma, diabetes, heart disease, weakened immune systems, and neurological or neurodevelopmental conditions) are at high risk from serious complications if they get influenza. These people should consider avoiding exposure to pigs and swine barns this summer, especially if sick pigs have been identified.
• If you have animals -- including swine -- watch them for signs of illness and call a veterinarian if you suspect they might be sick.
• Avoid close contact with animals that look or act ill.
• Avoid contact with pigs if you are experiencing flu-like symptoms. If you can't avoid pig contact when you are sick, wear protective clothing, gloves, and a mask that covers your mouth and nose.
• If you've been near pigs and see a doctor for flu-like symptoms, tell the doctor about your contact.
• If you develop flu symptoms, especially after pig contact, get treated right away. Both Tamiflu and Relenza are effective against H3N2v swine flu.

Just in case the H3N2v bug learns to spread easily among people, the CDC has developed a vaccine. Clinical trials are planned.

Meanwhile, as fall approaches, the CDC advises people to plan to get their seasonal flu vaccine. It may not protect against H3N2v, but human flu bugs are certain to start circulating before the 2012-2013 flu season is over.

SOURCES:CDC news teleconference with Joseph Bresee, MD, influenza division, CDC.CDC web site.Ken Severson, public information officer, Indiana State Department of Health.News release, Indiana State Department of Health.Ohio Department of Health web site.Hawaii Department of Health web site.

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