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The antigen characterization is listed in CDC Weekly reports.

In the latest report:

"Antigenic Characterization: CDC has antigenically characterized 157 influenza A (H3N2) viruses collected by U.S. laboratories since October 1 and found that 45 (29%) were similar antigenically to the vaccine strain A/Panama/2007/99 (H3N2), and 112 (71%) were similar to the drift variant, A/Fujian/411/2002 (H3N2). The A/Fujian strain predominated in Australia and New Zealand during the recent Southern Hemisphere influenza season and is a drift variant related to the vaccine strain, A/Panama/2007/99. Antibodies produced against the vaccine virus cross-react with A/Fujian/411/2002-like viruses, but at a lower level than against A/Panama/2007/99 (H3N2). Vaccine effectiveness depends, in part, on the match between vaccine strains and circulating viruses and cannot be determined by laboratory testing. Although vaccine effectiveness against A/Fujian/411/2002-like viruses may be less than that against A/Panama/2007/99-like viruses, it is expected that the current U.S. vaccine will offer some cross-protective immunity against the A/Fujian/411/2002-like viruses and reduce the severity of disease. One influenza A(H1N1) virus was antigenically characterized and was similar to the vaccine strain A/New Caledonia/20/99. "

Here is another report from the MA DOH website (which relies on CDC info):

"Influenza has been reported in all regions of the United States and has been widespread in 10 states (Arkansas, Colorado, Idaho, Nevada, New Mexico, Pennsylvania, Tennessee, Texas, Utah and Washington) and regional in 9 states. Also, this year is earliest since the 1976-77 influenza season that the percentage of specimens testing positive has exceeded 10%. Of the isolates typed by CDC, 99% of isolates were identified as type A and 1 % identified as type B. Over 80% of the A (H3N2) viruses have been identified as the A/Fujian (H3N2) strain. This strain has been associated with the more severe cases and deaths in children reported in the western states. Because of the changes in the influenza virus, the current vaccine may be slightly less effective in preventing influenza caused by the A/Fujian (H3N2) strain. However, the influenza vaccine is the best tool we have and it is expected to be effective in preventing severe disease and complications from influenza. Every year, people at high risk for complications from influenza are strongly recommended to get their flu shot as soon as possible."

From today's Chicago Tribune:

"Some doctors in California, Texas and Colorado say they have been overwhelmed by the severity of flu in children this year. On one day last week, Children's Medical Center in Dallas reported two dozen children with flu symptoms, most severe enough to need ventilators."

http://www.chicagotribune.com/news/local/chicago/chi-0312090138dec09,1,4626524.story?coll=chi-newslocalchicago-hed

Here's a report suggesting the outbreak is now beginning to take off in Northern California. Kaiser is well established there, and uses its network of hospitals to monitor the outbreak. Some there are using "epidemic" to describe the recent rise. I would assume that most of these are Fujian:

"Health giant Kaiser Permanente, which conducts influenza surveillance for the state health department, reported Monday that 390 patients in its Northern California region tested positive for the flu virus in the week ending Dec. 6.

``I have never seen anything like this,'' said Dr. Roger Baxter, a consultant who for the last eight years has overseen Kaiser's flu vaccine program in Northern California, where the health company serves 3.2 million patients. ``We're in an epidemic situation.''

The 390 cases last week represented a dramatic bump from the same week last year when Kaiser doctors reported only one case of the flu. Baxter said there has been an upswing in the number of flu cases at doctors' offices and Kaiser hospitals in San Jose, Santa Clara, San Francisco, Alameda and other areas. The week ending Nov. 29 there were 229 flu cases reported.

And it's still early in the flu season, which typically tapers off in March.

Baxter added that an abnormally high 30 percent of those people with flu-like symptoms who were tested for influenza last week received positive results for the virus. Typically, a 10 percent result indicates an outbreak."

http://www.bayarea.com/mld/mercurynews/living/health/7448956.htm