ICEID NEWS SCAN: Salsa and sickness, hand-hygiene gap, West Nile antibodies, 1918 pandemic

Jul 12, 2010 – ATLANTA

Salsa and guacamole as rising sources of illness
The proportion of restaurant-related illness outbreaks linked to salsa or guacamole has more than doubled over the past decade, to about 4%, according to findings presented today in Atlanta at the International Conference on Emerging Infectious Diseases (ICEID). The two food products contain diced raw items such as hot peppers, tomatoes, and cilantro that have been implicated in past outbreaks. The study, conducted by the US Centers for Disease Control and Prevention (CDC) with a researcher from the Oak Ridge Institute for Science and Education, showed that salsa- and guacamole-related outbreaks accounted for 1.5% of all restaurant-linked outbreaks from 1984 through 1997, but the figure rose to 3.9% from 1998 through 2008. Pathogens included Salmonella, norovirus, Shigella, and others. The illnesses resulted in 145 hospitalizations and 3 deaths, according to the meeting abstract. The investigators found that improper storage times or temperatures were reported in 30% of outbreaks involving the two food items, and food workers were cited as the contamination source in 20%. Magdalena Kendall of the Oak Ridge Institute said salsa and guacamole are often made in large batches, and even a small amount of contamination can affect many customers. The researchers suggest that, given the popularity of Mexican cuisine, restaurant workers need training materials on preparation and storage of salsa. Kendall said people preparing salsa and guacamole at home should also be aware that products containing raw ingredients should be carefully prepared and refrigerated to prevent illness.
Jul 12 ICEID abstracts (See Board 12)
Jul 12 CDC press release

Observers find little traction for hand-hygiene messages
In an observational study of hand-hygiene habits of Wellington, New Zealand, residents during the H1N1 pandemic, researchers found that about 1 in 4 failed to cover their mouth when they coughed or sneezed, according to findings presented today at the ICEID. Worse, only 5% covered their mouth using one of the recommended methods, such as a tissue, handkerchief, or elbow. The researchers, from the University of Otago in Wellington, observed three public areas in the city in August 2009: a train station, a hospital, and a shopping mall. At the time, public health officials had been conducting an educational campaign with posters, radio, and newspaper advertisements, according to a press release from ICEID. Medical students recorded the incidence of coughs and sneezes and individual response to the respiratory event. The most common behavior, seen in 64% of incidents, was covering the mouth with the hands. The group concluded that there is a gap between people's practices and public health messages.
Jul 12 ICEID abstracts (See Board 48)
Jul 12 ICEID press release

West Nile antibodies can persist for 6 years
Anti-West Nile virus (WNV) antibodies may persist as long as 6 years, meaning detection of the marker may not reliably indicate recent infection, researchers from the CDC reported today at the ICEID. They followed 59 patients who were hospitalized with confirmed WNV in 2003. Anti-WNV immunoglobulin-M was detected in 8 (24%) of 33 patients who were still participating in the study at 72 to 75 months. Those who had persistent antibodies were likely to be younger than those without them. The researchers suggest that physicians consider a patient's clinical and epidemiologic history when interpreting positive antibody findings to determine if they suggest acute disease or a previous infection.
Jul 12 ICEID abstracts (See Board 25)

Birth rates declined in wake of 1918 flu pandemic
Birth rates in the United States and Scandinavian countries dipped in the spring and summer of 1919, probably because of the 1918 flu pandemic, according to an international group that presented its findings at ICEID. They explored morbidity, mortality, and birth data from national surveillance systems in the US, Denmark, Sweden, and Norway from 1911 to 1930. For comparison, they developed a seasonal model to estimate what baseline birth rates would have been in the absence of flu activity. For all three countries the data showed an approximate 10% to 20% drop in birth rates, or about 2.8 missing births per 1,000 population, from April through August of 1919, about 6 to 9 months after the fall peak of the 1918 pandemic. There were no other significant deviations from expected birth rates during the 20-year period studied. The researchers suggest that the reduction in births could have resulted from spontaneous first-trimester abortions as a complication of maternal flu infections in the fall of 1918.
Jul 12 ICEID abstracts (See Board 119)

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