ICEID NEWS SCAN: Thermal scanners, asymptomatic H1N1 in HCWs, pandemic vaccine wariness, dengue in Florida, foodborne disease patterns

Jul 13, 2010 – ATLANTA

Thermal scanners are poor flu predictors
Thermal scanners for screening travelers do moderately well at detecting fever, but do a poor job at flagging influenza, according to researchers from New Zealand who presented their findings today at the International Conference on Emerging Infectious Diseases (ICEID) in Atlanta. They assessed the performance of the machines from Aug 21 through Sep 12, 2008, on 1,275 passengers arriving from Australia at Christchurch International Airport. The investigators took the travelers' tympanic temperatures and obtained respiratory samples for influenza testing from 1,268 of them. The positive predictive value for fever was 1.5% for thermal scanners and 4.1% for tympanic thermometers. For influenza, the positive predictive value for the two techniques was 2.8%. None of the 30 passengers who tested positive for influenza had a tympanic temperature of 37.8°C (100°F) or higher, and only 2 had temperatures of at least 37.5°C (99.5°F). Three were asymptomatic. The group concluded that fever is a poor predictor of influenza, which limits the efficacy of thermal screening at entry points.
Jul 13 ICEID abstracts (See Board 168)

One fourth of healthcare workers had asymptomatic H1N1
Serologic testing of healthcare workers in a group of outpatient pediatric clinics in a Japanese city during the early stages of pandemic H1N1 community transmission showed that 35 (28.5%) of 140 workers who were tested were positive for infection, but all but 1 asymptomatic, researchers reported today at ICEID. The researchers used hemagglutination testing to measure antibodies against the pandemic flu virus. Healthcare workers filled out a questionnaire to report their history of flu-like illness from May 2009 until the sampling day. Only one worker reported a flulike illness. Doctors had the highest attack rate. Given that most of the workers wore surgical masks or N-95 respirators, more strategies are needed to protect healthcare workers from pandemic flu, the group concluded.
Jul 13 ICEID abstracts (See page 131)

Religious beliefs, suspicions blocked vaccine uptake in Jordan
Suspicion, misinformation, rumors, and religious beliefs contributed to extremely low pandemic vaccine uptake in Jordan, representatives from the country's health ministry reported yesterday at ICEID. They conducted a survey in late December and early January in healthcare centers in Amman, Irbid, and Karak to assess the public's knowledge about pandemic H1N1 and attitudes about the vaccine. The survey was conducted about a month after the launch of the vaccine, which was available for free at clinics. Of 889 adults, most were knowledgeable about the disease, but only 7 had been vaccinated. About 70% said they were afraid of the vaccine, and 28% said they were ready to take the vaccine. Researchers said the public suspicion about the vaccine was fueled by satellite TV reports on purported pharmaceutical company conspiracies. The health ministry officials told CIDRAP News that religious beliefs contributed to extremely low vaccine uptake as well. Many have faith that they will be protected from the virus without the vaccine. The official said the country ordered $75 million worth of vaccine and is working to exchange much of it for other pharmaceutical products.
Jul 12 ICEID abstracts (See page 72)

Seroprevalence testing suggests more dengue cases in Florida
In the wake of the re-emergence of dengue virus infections in Florida, a seroprevalence study has found that even more patients have evidence of recent or presumed recent infections, according to findings presented today at ICEID. Researchers from the Centers for Disease Control and Prevention (CDC) and the Florida Department of Health questioned 240 patients about their illness history and collected their serum samples. Forty-one percent of the study subjects had evidence of previous dengue infection on IgG enzyme-linked immunosorbent assay (ELISA), and 13 had evidence of either an acute, recent, or presumed recent infection. Other testing methods showed that some of the infections were caused by a strain of dengue virus, serotype 1, that is genetically similar to viruses isolated in Mexico.
Jul 13 ICEID abstracts (See Board 247)

Homes, food service settings differ in foodborne illness patterns
Private homes, as well as restaurants and caterers, are significant settings for foodborne illness outbreaks, and disease patterns vary by setting, CDC researchers reported yesterday at ICEID. Looking at outbreak reports from 1998 to 2008, they found that 1,546 outbreaks involved homes, 7,921 were traced to restaurants or delis, and 886 involved caterers. Reported illnesses from home-based outbreaks were more likely to affect younger people and involve environmental or animal reservoirs. Pathogens in restaurant outbreaks were more likely to involve human reservoirs. Fish was the most commonly implicated food commodity in home settings, and poultry was the most common in restaurants, delis, and caterers. The CDC group concluded that though foodborne disease outbreak reporting was less complete in home settings, the differences that emerged by setting may be useful for food safety education purposes.
Jul 12 ICEID abstracts (See Board 10)

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