News Scan for May 13, 2016

News brief

Sprout-related outbreak over after 26 sickened in 12 states

A Salmonella outbreak linked to alfalfa sprouts that sickened 26 people in 12 states appears to be over, the US Centers for Disease Control and Prevention (CDC) said today in a final notice about the event.

The investigation revealed that one lot of contaminated seeds is the likely source of the outbreak. Illnesses were associated with sprouts grown by different producers and involved two different strains: one patient was infected by Salmonella Kentucky, while the others had Salmonella Muenchen. Eight patients were hospitalized, and no deaths were reported.

In the initial outbreak announcement on Feb 23, the CDC said it had received reports on 13 illnesses from 4 states. Patient interviews and traceback investigations in several states pointed to sprouts produced by Kansas-based Sweetwater Farms. Samples from irrigation water at the facility yielded Salmonella Kentucky and Salmonella Cubana, but not Salmonella Muenchen.

The probe of continuing reports of Salmonella Muenchen illnesses led to other sprout producers. All of them, plus Sweetwater farms, had used a common seed lot that had been found in Food and Drug Administration testing to contain the Cubana strain.
May 13 CDC final outbreak announcement

 

Deaths in hospitalized patients rose over China's 3 H7N9 epidemic waves

Risk of death from H7N9 infection was highest during China's second and third epidemic waves, also shifting to affect younger people and rural residents, according to a study yesterday in Emerging Infectious Diseases.

Researchers from the World Health Organization (WHO), the University of Hong Kong, and the Chinese Center for Disease Control and Prevention evaluated case data from patients hospitalized with H7N9 infections during China's three epidemic waves (March to September, 2013; winter 2013 to 2014; and winter 2014 to 2015).

Risk of death in hospitalized patients was about five times higher during the third wave and 3 times higher during the second wave compared to the first epidemic, the authors said. The proportion of severe infections also rose over time among people from small towns and rural areas.

Though risk for death was highest among people 65 years and older across all waves, people with severe disease tended to be slightly younger during the second and third waves. Case severity and risk of death decreased in Jiangxi and Fujian provinces over the second and third waves, with increased severity observed in Zhejiang, Jiangsu, and Guangdong provinces.

The authors did not observe shifts in infected case-patient age, rural versus urban demographics, or underlying medical conditions that could fully explain the shift in death risk. Conditions that may have contributed included suboptimal treatment at rural hospitals, better familiarity with the disease in urban centers, and a potential increase in pathogenicity caused by genetic changes in the virus, the authors said.
May 12 Emerg Infect Dis study

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