Oct 19, 2012
CDC sees a few signs of US flu activity
The United States had a few glimmers of influenza activity last week, but most markers remained low, the US Centers for Disease Control and Prevention (CDC) said today. Outpatient visits for flu-like illness stayed well below the national baseline, but deaths from pneumonia and flu rose to the epidemic threshold of 6.3%. The percentage of respiratory specimens that were positive for flu rose slightly last week from 2.6% to 3.9%, which the CDC said was somewhat elevated for this time of year. One pediatric flu death was reported and was linked to an undetermined influenza A subtype. Iowa was the only state that reported local geographic spread of flu, while 32 states and the District of Columbia reported sporadic activity. No new cases of swine-origin variant H3N2 (H3N2v) or other novel flu types were reported. Of 129 positive flu tests last week, 61 were influenza A and 68 were influenza B. Of the influenza A viruses, 43% were H3N2, 7% were 2009 H1N1, and 51% were not subtyped. In a separate update, the CDC said that of the 135 million doses of flu vaccine expected to be produced this season, 114.6 million have been distributed.
Oct 19 CDC influenza update
Oct 19 CDC influenza summary
CDC flu vaccine distribution update
Prophylactic oseltamivir may help control nursing home flu outbreaks
A study from Australia suggests that the prophylactic use of oseltamivir (Tamiflu), along with treatment, may reduce the size and duration of influenza outbreaks in nursing homes. Researchers conducted a cluster-randomized trial in which 16 aged-care facilities (ACFs) were assigned to use treatment only (T) or treatment and prophylaxis (T&P) in response to confirmed flu cases and epidemiologically linked influenza-like illnesses, according to their Oct 17 report in PLoS One. In the T facilities, only ill patients received oseltamivir (75 mg twice daily for 5 days); in T&P facilities, oseltamivir was used in sick patients and in those living or working in the same wing or floor of the facility as a confirmed flu case; prophylaxis was 75 mg once a day for 10 days. The study covered the 2006 through 2008 Australian flu seasons. The flu attack rate was found to be significantly lower in residents of T&P facilities (91 of 397, 23%) than in T facility residents (93 of 255, 36%) (P=.002). In addition, flu outbreaks were significantly shorter in the T&P facilities: 11 days versus 24 days (P=.04). The flu attack rate also was lower in staff members in T&P facilities, but not significantly so. "Our trial lacked power but these results provide some support for a policy of 'treatment and prophylaxis' with oseltamivir in controlling influenza outbreaks in ACFs," the report says.
Oct 17 PLoS One report
Novavax reports good preliminary phase 1 findings for H5N1 vaccine
Novavax, a pharmaceutical company in Rockville, Md., announced this week that in preliminary results of two phase 1 clinical trials, its H5N1 avian influenza vaccine candidate was found to be safe and effective. The company conducted the trials under its contract with the US Biomedical Advanced Research and Development Authority (BARDA). The goal was to test the virus-like particle (VLP) H5N1 vaccine at different dose levels with and without 1 of 2 undisclosed adjuvants. The two trials involved 666 healthy adults who received an intramuscular vaccine or placebo at day 0 and day 21. In findings after the first 42 days, adjuvanted vaccines provoked strong immune responses (seroconverion and seroprotection rates of 86% to 100%) based on hemagglutination inhibition assay (HAI) at all doses tested. The unadjuvanted vaccine at the 45-microgram dose yielded more than 82% seroconversion and seroprotection in both trials. No serious adverse events were observed. The patients who received the adjuvanted vaccines showed signs of protection against a different H5N1 strain. Gregory Glenn, MD, Novavax's senior vice president and chief medical officer, said the results give the company enough data to advance to later-stage testing.
Oct 17 Novavax press release
European panel: Cause of Pandemrix-narcolepsy link remains unclear
Data from Finnish researchers exploring a potential cause for the association between vaccination with Pandemrix during the 2009 flu pandemic and narcolepsy are insufficient to draw any conclusions, according to a press release today from the European Medicines Agency (EMA). The agency's Committee on Human Medicinal Products (CHMP) evaluated preliminary results from the Finnish National Institute of Health and Welfare, which had looked into differences in immunologic responses to different pandemic flu vaccines as a possible cause of the increased incidence of narcolepsy noted after vaccination with GlaxoSmithKlein's (GSK's) Pandemrix in some European countries. CHMP determined that with current evidence, the cause of Pandemrix-associated narcolepsy remains unknown. The CHMP encourages further studies on the cause and expects GSK to take into account the Finnish findings in its continuing research, says the release. The European Centre for Disease Prevention and Control (ECDC) released a technical report in September confirming the narcolepsy-Pandemrix link. Pandemrix was not used in the United States.
Oct 19 EMA press release
Sep 20 CIDRAP News story on ECDC technical report