Few flu hot spots remain, but virus still making hospitalization impact
Flu activity continues to hang on in a few northeastern states, but most markers declined further last week, except for the hospitalization rate, the US Centers for Disease Control and Prevention (CDC) said today.
The percentage of respiratory specimens that tested positive for flu dropped to 6.5% last week, down from 7.6% the week before. Most flu circulating in the United States now is influenza B, which was found in 89% of the positive specimens.
Nationally, the percentage of clinic visits for flulike illness remained below the baseline level and, at 1.4%, stayed the same as the previous week.
The CDC saw some regional variation for that marker, especially given that 2 of its 10 areas are still above their baselines—one in the northeast and one in the upper west. Regional percentages ranged from 5.2 to 14.6.
However, hospitalization rates continued to rise, with the overall level rising from 62.4 per 100,000 population to 64.3 last week. The rate for seniors set another record last week, climbing from 313.8 per 100,000 to 316.8, the highest recorded since the CDC started collecting the data on adults in the 2005-06 flu season.
Five more pediatric flu deaths were reported, two of them occurring in January and February. The three more recent deaths involved influenza B. So far 133 pediatric flu deaths have been reported this season.
Overall deaths from pneumonia and flu were below the epidemic threshold.
Only three states reported widespread geographic flu spread, all of them located in the northeast: Connecticut, Massachusetts, and New York.
May 1 CDC FluView
Sanofi recalls some quadrivalent flu vaccine lots for loss of potency
Sanofi Pasteur has recalled three lots of its Fluzone Quadrivalent (four-strain) flu vaccine because routine tests showed that they lost potency before their expiration date, the CDC announced today.
The lot numbers being recalled are UI196AA, UI190AC, and UI190AD, which involve vaccine sold in multidose vials. The Food and Drug Administration sets potency standards for flu vaccines in part because when a vaccine falls below a pre-specified potency limit, it may be less effective.
Because flu activity is low and declining, the CDC is not recommending revaccination for those who received vaccine from the recalled lots. The agency said the reduced potency does not pose a safety concern for those who received the vaccine.
Tests showed that the influenza A/H3N2 and influenza B Victoria components of the vaccine had reduced potency, the CDC reported. Potency in the other two components—H1N1 and B Yamagata—was maintained.
May 1 CDC notice
Burkina Faso reports seven more H5N1 outbreaks
A series of H5N1 avian influenza outbreaks in Burkina Faso is continuing, with seven more reported to the World Organization for Animal Health (OIE) this week.
The outbreaks affected poultry farms in three provinces, Poni, Kodiogo, and Bazega, the government's director of veterinary services said in his Apr 29 report to the OIE. Of 18,264 susceptible birds, 16,009 died, and the rest were slaughtered to stop the virus. The bird species were not listed.
The H5N1 virus resurfaced in Burkina Faso in February after being absent since 2006. The government reported the first four outbreaks on Apr 1 and seven more on Apr 17.
Apr 29 OIE report
In other H5N1 news, Hong Kong's government said yesterday that preliminary testing identified an H5 avian flu virus in a sick Oriental magpie robin in the territory. Hong Kong has reported the H5N1 virus in wild birds a number of times before. The find prompted the government to remind poultry farmers to strengthen biosecurity measures.
Apr 30 Hong Kong statement