NEWS SCAN: Cantaloupe Listeria outbreak over, flour suspected in cookie dough outbreak, H5N1 risk perceptions

Dec 9, 2011

CDC declares cantaloupe Listeria outbreak over after 146 cases, 30 deaths
A Listeria monocytogenes outbreak linked to cantaloupes from Colorado appears to be over after 146 illnesses and 30 deaths in 28 states, the Centers for Disease Control and Prevention (CDC) announced late yesterday. The totals include 7 more cases and 1 more death since the last CDC update on Nov 2. Investigators determined that cantaloupes grown at Jensen Farms of Granada, Colo., were the source of the outbreak. Illness onset dates ranged from Jul 31 to Oct 27. Most of the patients were older than 60, and the median age of those who died was 82.5, the CDC said. Of 144 patients for whom information was available, 142 were hospitalized. Colorado had the most cases (40) and deaths (8). The CDC said seven of the illnesses were related to pregnancy, with three in newborns and four in pregnant women. One woman had a miscarriage. A report published today in Food Safety News said the 30 deaths represent the worst death toll in a US foodborne outbreak since 1911, when 48 people in Boston died after drinking contaminated raw milk.
Dec 8 CDC update
Dec 9 Food Safety News story

Flour tagged as 'prime suspect' in 2009 cookie dough outbreak
The cause of the 2009 Escherichia coli outbreak in Nestle raw cookie dough has not been definitely identified, but investigators call raw flour a "prime suspect" in a thorough report published today in Clinical Infectious Diseases. The authors, from the CDC and four state health departments, recommend reformulating products to make them as safe as ready-to-eat foods and call for better consumer education about eating unbaked goods designed to be baked. The outbreak involved 77 confirmed E coli infections in 30 states, including 35 hospitalizations and 10 cases of hemolytic uremic syndrome, which can be deadly. The researchers write that a single batch of contaminated flour might have been used in multiple lots and varieties of dough over time, which fits the various products implicated. Flour does not typically undergo a "kill step" for pathogens, unlike other ingredients in the dough, like pasteurized eggs, molasses, sugar, baking soda, and margarine. Chocolate was also ruled out, as it was not strongly associated with the cases. The authors say that several cookie dough manufacturers reported having implemented the use of heat-treated flour, but they urge all companies to take that step. They also say the practice of eating raw cookie dough appears to be common, especially in girls and young women. Several outbreak patients said they had no intention of baking the dough before they ate it.
Dec 9 Clin Infect Dis abstract
Dec 9 EurekAlert press release on the study

Hong Kong residents, poultry workers see low avian flu risk
Hong Kong poultry workers and consumers see the risk of avian flu as being fairly low, even though Hong Kong consumers are less likely to buy poultry from live markets, according to two surveys published in the current issue of Emerging Infectious Diseases (EID). In the first study, scientists from the Chinese University of Hong Kong and the UK's University of Oxford found that fairly low percentages of surveyed poultry workers in 2009 knew the H5N1 avian flu virus could infect live poultry (60%), humans (50%), and domesticated birds (45%). Rates of correctly identifying risk factors varied widely: consuming undercooked poultry (69%), touching bird feces (60%), slaughtering poultry (29%) ,and eating undercooked eggs (14%). More than one fourth of respondents were unsure whether human cases had been confirmed in Hong Kong. The survey involved 360 workers, which represented a 68% response rate.
December EID report
The second study, published as a letter from University of Hong Kong researchers, reported on 461 adults who completed phone surveys in 2005-06 and again in 2010, which was 26% of the original 1,760 adults recruited. China began placing restrictions on Hong Kong poultry in 2006. The investigators found that the proportion of respondents who bought live poultry dropped from 73% in 2005-06 to 41% in 2010, and the percentage of those who bought such birds at least monthly dropped from 50% to 15%. At the same time, the respondents worried less about contracting avian flu from live birds, as the percentage of those who somewhat agreed, agreed, or strongly agreed that buying live poultry involves a risk dropped from 42% in 2005-06 to 31% in 2010.
December EID letter

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