Some US flu activity indicators up slightly
Influenza activity in the United States has picked up slightly but is still well below epidemic levels, while the mismatch between circulating H3N2 viruses and the vaccine strain rose to 58%, the Centers for Disease Control and Prevention (CDC) said in its weekly update today.
Of 13,398 specimens tested by US labs, 2,274 (17.0%) were positive for influenza for the week that ended Nov 29. That's up from 12.6% the week before. And 5.4% of all deaths were attributed to pneumonia and influenza, which is up from 5.3% the week before but below the epidemic threshold of 6.5%.
Eight of the 10 US regions experienced elevated activity of influenza-like illness (ILI) in outpatient settings, compared with only 4 the week before. And Puerto Rico and six states (Alabama, Florida, Georgia, Louisiana, Mississippi, and Texas) reported high ILI activity. The week before only Louisiana and Puerto Rico had high ILI activity.
Finally, six states—Alaska, Florida, Illinois, Louisiana, Maryland, and North Carolina—and Puerto Rico reported widespread flu activity, up from two states.
Among the 2,274 influenza-positive specimens, 2,129 (93.6%) were influenza A and 145 (6.4%) were influenza B. Of the 661 "A" viruses that were subtyped, 656 (99.2%) were H3N2 and only 5 (0.8%) were 2009 H1N1.
A total of 66 of 114 H3N2 viruses tested, or 58%, did not match well with the H3N2 component in the vaccine, a phenomenon reported by the CDC yesterday (see related story). That is up from 52% the week before.
No new pediatric flu deaths were reported, leaving the season total at five.
Dec 5 CDC FluView update
India reports 4th H5N1 outbreak; Japan detects H5N8 in wild bird
Highly pathogenic H5N1 avian flu has struck a fourth duck flock in India's Kerala state, while Japan has detected H5N8 avian flu in a wild-bird sample, according to separate reports posted yesterday by the World Organization for Animal Health (OIE).
Of the village flock of 5,500, 500 ducks died, and testing on Dec 3 confirmed H5N1 as the culprit, the report said. The flock is in Kottayam in the southwest part of the country. The previous three outbreaks, the first of which was reported Nov 25, were also in Kerala state.
Officials have begun control efforts such as disinfection and control of poultry movement within the country in response to the most recent outbreak, the OIE report said. It began on Nov 20, the same date as the other reported outbreaks.
Dec 4 OIE report on India outbreak
In related news, highly pathogenic H5N8 has again been detected in Japan in a fecal sample of a bird in the Anatidae family, which includes ducks, geese, and swans, according to the second OIE report. Officials were not able to identify the exact species.
The sample was collected in Tottori prefecture. Japanese officials also have recently detected H5N8 in fecal samples in neighboring Shimane prefecture and in Chiba prefectures, near Tokyo.
Dec 4 OIE report on Japan detection