NEWS SCAN: Listeria meningitis mortality, norovirus shellfish assessment, H1N1 and bacterial infections, Sanofi flu vaccine studies

Oct 24, 2011

Study: 5-year mortality rate doubles after diagnosis of Listeria meningitis
Mortality in Danish adults who had Listeria meningitis doubled in the first 5 years after diagnosis compared to other patients, according to a study in the Journal of Infection. Researchers analyzed data from the Danish National Hospital Register and the Danish Register of Causes of Death from 1977 through 2006 and identified 114 patients with Listeria meningitis who survived their first year after diagnosis and 1,026 matched healthy controls. They found that the overall adjusted mortality rate ratio (MRR) for the first 5 years of follow-up was 2.35 (95% confidence interval [CI], 1.60-3.45) but then dropped to 0.93 (95% CI, 0.56-1.55) after 5 years. When they looked specifically at cancer, the 5-year adjusted MRR rose to 3.09 (95% CI, 1.49-6.38), but then dropped to 0.66 (95% CI, 0.19-2.23). The researchers conclude, "To improve survival this patient population should be meticulously screened for predisposing conditions, mainly underlying malignant diseases."
Oct 21 J Infect abstract

US, Canada launch norovirus risk assessment for certain shellfish
The US Food and Drug Administration (FDA) announced on Oct 20 that it and federal counterparts in Canada are undertaking a risk assessment of norovirus in oysters, clams, and mussels. The study will explore contamination during growth, harvest, and postharvest processing and will examine the impact of prevention practices and controls. As part of the risk-assessment process, the FDA is requesting comments, scientific data, and other information by Jan 18, 2012. Contact information is included in a Federal Register docket listed below.
Oct 20 FDA statement
Oct 20 Fed Regist docket listing

Invasive bacterial infections increased during 2009 pandemic
The 2009 H1N1 influenza pandemic was associated with higher levels of bloodstream infections (BSIs) caused by Staphylococcus aureus and Streptococcus pyogenes in all age-groups and by higher levels of Streptococcus pneumoniae BSIs in children, according to an Isreali study in Clinical Infectious Diseases. The investigators studied BSI data from 2006 through 2010 for eight hospitals that accounted for 33% of hospitalizations in Israel. They found the incident rate ratio (IRR) of S aureus and S pyogenes BSIs in all age-groups during the winter of 2009-10 to be 1.5 (95% CI, 1.2-1.7) and 3.3 (95% CI, 1.9-5.8), respectively, compared with the 2006-07 through 2008-09 flu seasons (P < .0001). In comparison, the IRR for S pneumoniae BSIs in children but not in adults for the winter season was 6.5 (95% CI, 2.6-11.8, P < .0001). Non-pandemic flu seasons, by contrast, were characterized by increased rates of S pneumoniae BSIs but not of S aureus and S pyogenes BSIs compared with non-flu periods.
Oct 21 Clin Infect Dis abstract

Sanofi announces new findings for quadrivalent, high-dose flu vaccines
Sanofi Pasteur announced the latest study results for two of its influenza vaccines, a quadrivalent influenza vaccine (QIV) in development that includes two instead of one influenza B strains and a high-dose flu vaccine already approved for people 65 and older. The findings were announced at the Infectious Diseases Society of America annual meeting in Boston, according to Sanofi press releases. In the first study, researchers reported that the QIV was safe and immunogenic in adults age 65 and older, which it said is consistent with phase 2 results in 2010. The double-blind, active-controlled multicenter study included 675 people age 65 and older who were randomized to receive one dose of 2010-11 trivalent inactivate vaccine (TIV) containing the B strain from the Victoria lineage, an investigational TIV containing the Yamagata lineage, or the QIV. The QIV was found noninferior based on geometric mean titer (GMT) and noninferior to all but the pandemic 2009 H1N1 strain based on seroconversion. In a superiority test, QIV was found superior to the Yamagata strain but not the Victoria strain, though GMTs were numerically superior and statistically noninferior for the latter. Injection-site reaction patterns were similar for all groups.
Oct 21 Sanofi QIV press release
The second multicenter trial included 639 seniors from 65 to 96, who were randomized to receive the high-dose, 60-microgram (mcg) vaccine or the standard, 15-mcg one. The study also included younger adults who received the standard-dose vaccine. Seniors who received the high-dose vaccine had statistically significant higher antibody responses compared with those who received the standard vaccine. Immunogenicity measured by seroconversion and GMT was higher for all three strains, and seroprotection was higher for the H1N1 and B strains. Injection-site reactions were more common in elderly people who received the high-dose vaccine, which were mild to moderate and resolved in 3 to 7 days.
Oct 21 Sanofi high-dose flu vaccine press release

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