Nov 30, 2009 (CIDRAP News) – The number of states with widespread pandemic flu activity dropped for the third week in a row, but the virus continued to take a heavy toll on children, with at least 27 more pediatric deaths reported the week of Nov 15 to 21, the US Centers for Disease Control and Prevention (CDC) said today.
Thirty-two states were still reporting widespread activity, 11 fewer than the previous week, according to the CDC's surveillance report. Visits to physicians' offices for influenza-like illnesses also dropped for the fourth consecutive week, with all regions of the country reporting declines. However, the CDC pointed out that doctor's visits for flu symptoms are still high for this time of year.
The CDC received 35 pediatric flu death reports last week, of which 27 were lab-confirmed pandemic H1N1 infections. Seven involved influenza A viruses that were not subtyped, and one was a seasonal H1N1 death that occurred in March and will be included in the total for the 2008-2009 flu season. Nineteen states reported pediatric flu deaths, with New Mexico listing 8 deaths. The new reports raise the total number of child deaths from the pandemic virus to 198.
The percentage of deaths from pneumonia and influenza in the CDC's 122 Cities surveillance system rose last week, remaining above the epidemic threshold for the eighth consecutive week.
The CDC said hospitalization rates remained higher than expected for this time of year and were highest in young people, especially in the newborn through age 4 group. The number of lab-confirmed hospitalizations since Aug 30 is 29,348, with the number of lab-confirmed deaths at 1,224.
The CDC has said the totals of lab-confirmed cases greatly underestimate the true burden of the disease, and on Nov 12 it unveiled a new counting method that bases estimates on state reports of confirmed cases and surveillance data from its Emerging Infection Program Network. The agency said it expects to update those estimates every 3 to 4 weeks.
Of the respiratory specimens tested for flu during the week, over 99% of all subtyped viruses were the pandemic H1N1 virus.
Two more cases of oseltamivir-resistant H1N1 influenza were identified last week, raising the nation's total since Sep 1 to 13. All the isolates were sensitive to the neuraminidase inhibitor zanamivir. The CDC emphasized that sporadic cases of resistance in patients undergoing oseletamivir prophylaxis or treatment are expected.