CDC officials are talking to reporters about the flu outbreak. Here’s what they’re saying.
The officials are Anne Schuchat, of the agency’s science and public health program, and Nancy Cox, chief of the influenza division at the National Center for Immunization and Respiratory Diseases.
1:26 Schuchat: Here’s a case count by state, updated at 11 a.m. this morning. There are 141 cases confirmed in 19 states. There is still only one confirmed death.
1:28 The median age of patients is 17, with a range of one to 81 years. The most recent onset of illness is April 28; cases do continue to occur. We expect to see more cases in more states.
1:29 Sebelius has decided to purchase 13 million more courses of antiviral drugs, to replenish the stockpile supplies that are now being sent out to the states.
1:30 The U.S. is shipping 400,000 courses of antiviral drugs to Mexico.
1:31 Harvard poll finds 59% of Americans are washing their hands or using hand gel more often.
1:36 Cox: Countries are sharing the genetic sequence data derived from the viruses. We now have genetic information available from six countries. “All of the genes of all of the viruses that we’ve examined to date are 99% to 100% identical.” This means it will be “somewhat easier to produce an influenza vaccine, because the viruses that are spreading are so similar to each other.”
1:39 Different techniques can be used to grow seed virus for making a vaccine. In a traditional technique called reassortment, the new H1N1 virus is combined with a different virus that grows well in eggs. Another technique, reverse genetics, can also be used. It will take about three weeks to create the seed virus. “If the virus cooperates and grows well, we will soon be able to distribute candidate vaccine virus to the manufacturers.”
1:41 Then the companies need eight to 10 weeks to produce pilot lots to see what dosage of the vaccine will be required.
1:44 Schuchat: We’re estimating an attack rate (a measure of transmissibility) that’s fairly high, in the 25% to 30% rate. That’s consistent with seasonal influenza, which spreads easily from person to person, particularly within families.
1:45 “We do not see the markers for virulence” that are in the 1918 virus that caused the worst pandemic of the 20th century. Still, there’s a lot scientists don’t know about the relationship between genetics and virulence. The gene sequences are in the public domain, to allow researchers to study them.
1:47 A reporter asks about officials’ move away from the term “swine flu” and toward “H1N1.” Schuchat: We understand the confusion about the nomenclature. “We’re in a transition state where we’re trying to get away from the word swine,” because people in the U.S. are not getting this infection by being exposed to pigs. Here’s our post on the naming question from earlier this week.
1:49 Trying to estimate the severity of the disease at this point is like trying to estimate a baseball player’s batting average one week into the season. In Mexico, as they have begun to increase surveillance, they have found more cases of mild disease. Seasonal flu has a spectrum of severity — 200,000 people are hospitalized for the disease every year, including 20,000 children.
1:52 “As we do our investigations here in the U.S., we may find that there were cases earlier” than the first known U.S. case, which was in late March. But at the moment, the CDC’s priority is focusing on the response.
1:55 Cox: Officials are watching for the possibility of resistance to antiviral drugs. More generally, they’ll be tracking the molecular evolution of the virus and trying to understand what that evolution might mean.
2:02 Manufacturers have already produced “a great deal” of seasonal flu vaccine for this fall. If a vaccine for the new virus is prepared, it would be prepared either in parallel with or after the seasonal vaccine is already produced.
2:07 The call is over.
Image of a flu virus particle via CDC