NEWS SCAN: H1N1 vaccine effectiveness, pandemic vaccine in hospitals, milk-related illnesses, fungal infections and tornadoes

Aug 1, 2011

Researchers show vaccine effective against H1N1 hospitalization
Australian researchers found that last year's influenza vaccine protected against hospitalization for pandemic 2009 H1N1 flu, according to a study in Vaccine. Using data collected from 15 sentinel hospitals in all of Australia's states and territories from March through November of 2010, the research team identified 238 hospitalized patients with confirmed 2009 H1N1 flu, 64 with seasonal flu, and 867 controls who tested negative for flu. Of those, the scientists could confirm vaccination status in 165, 40, and 558, respectively. The rate of receiving a vaccine containing the 2009 H1N1 strain in those three groups was 24%, 43%, and 54%, respectively, and the authors determined that the adjusted vaccine effectiveness against hospitalization for 2009 H1N1 flu was 49% (95% confidence interval, 13% - 70%). They concluded, "Longer term studies are required to assess the effectiveness of influenza vaccination against hospitalization against future circulating strains of influenza."
Jul 31 Vaccine study

Seasonal flu shots drive pandemic vaccine uptake in health workers
Having received the previous season's trivalent vaccine was the most powerful predictor for healthcare workers' receiving the 2009 H1N1 vaccine, according to a study in Vaccine. The study was based on a 20-question survey conducted from Jan 20, 2010, to Apr 12, 2010, at hospitals in Hong Kong, Singapore, and Leicester, United Kingdom, when the world was at the World Health Organization's highest pandemic alert level. Researchers received responses from 2,100 frontline healthcare workers. Overall, uptake was low, ranging from 13.5% to 41.3%. The researchers found that many of the workers overestimated the vaccine's side effects and underestimated their risk of contracting the disease. In Hong Kong, workers with more patient contact were more reluctant to be vaccinated, and researchers suggested that they could have relied too heavily on triage systems or been influenced by a report of a healthcare worker who apparently developed limb weakness after immunization. The group concluded that although more studies are needed to tease out uptake variables in different countries, the findings demonstrate a key role for seasonal vaccination in helping promote future acceptance of a pandemic vaccine.
Jul 30 Vaccine abstract

Illnesses linked to pasteurized and raw milk
Five people in Pennsylvania contracted Yersinia entercolitica infections from drinking pasteurized milk from Brunton Dairy in Aliquippa, Pa., the Pennsylvania Department of Health (PDH) announced in a Jul 29 press release. The five people, three young children and two older adults, experienced diarrhea and other symptoms. Dr. Elia Avila, the state secretary of health, recommended that any glass-bottled milk from the dairy be returned until completion of the outbreak investigation. The dairy is cooperating with the investigation and stopped producing milk at its on-site pasteurization facility, officials said. Yersiniosis is relatively uncommon, with about 1 case per 100,000 people per year in the United States, and it most often affects young children, according to the Centers for Disease control and Prevention (CDC). Raw or undercooked pork is the most common source of infection; other sources include unpasteurized milk and untreated water.
Jul 29 PDH press release
CDC information on yersiniosis
Meanwhile, the number of Campylobacter jejuni infections linked to raw milk from a cow-share farm in Alaska's Matanuska-Susitna Valley has increased to 7 confirmed and 11 suspected cases, Alaskan health officials said in an Epidemiology Bulletin dated Jul 28. Four cases were cited when the outbreak was first reported in late June. The bulletin said the same rare Campylobacter strain has been found in all the confirmed cases and in manure samples from the farm, though not in bulk-tank milk from the farm. Officials noted that C jejuni is "notoriously difficult to culture from environmental specimens other than raw stool" and said the outbreak poses an ongoing threat to consumers of milk from the farm.
Jul 28 Alaska Epidemiology Bulletin

Unusual fungal infections surface in Missouri tornado victims
In the first report of its kind related to a tornado, 13 patients who were injured in the category 5 twister that hit Joplin, Mo., on May 22 were diagnosed as having necrotizing soft-tissue infections caused by Mucormycetes fungus. The suspected cases were identified by the county and state health officials, who enlisted the US Centers for Disease Control and Prevention's (CDC's) help in identifying the isolates and investigating the outbreak. As detailed in Morbidity and Mortality Weekly Report (MMWR), all of the patients had had received surgical debridement for their wounds, with six requiring removal of foreign bodies such as splinters. Ten had been admitted to the intensive care unit, and five died. Laboratory analysis for all 13 patients yielded the Mucormycete Apophysomyces trapeziformis. The CDC said the fungus, found in soil, decaying wood, and other organic matter, can produce an opportunistic infection in people with immune system compromise but can also cause illness in healthy people who have been exposed to the spores after traumatic implantation. Illness clusters have been reported after tsunamis and volcano eruptions. The authors noted that early diagnosis, aggressive debridement, and systemic antifungals can improve outcomes.
Jul 29 MMWR report
In a CDC blog post today, Molly Gayden, who worked in the CDC's mycotic disease branch as part of her masters of public health internship, wrote the first illnesses caused a lot of anxiety in the community, especially among relief workers who thought they might be at risk to the then-unknown pathogen. She wrote that the trauma survivors played an important role by providing crucial information about how they were injured. "Knowing whether a survivor was hit by a tree branch or a two-by-four can help determine if there was a common source of exposure to the fungus."
Aug 1 CDC blog post

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