NEWS SCAN: Turtle-borne Salmonella , raw milk outbreak, hospital pathogens, guinea pigs as flu B models, Lyme map

Feb 2, 2012

CDC reports 132 salmonellosis cases in 18 states from pet turtles
The US Centers for Disease Control and Prevention (CDC) today reported an 18-state outbreak of 132 Salmonella infections linked to pet turtles that may in large part have been illegally obtained, according to a notice in Morbidity and Mortality Weekly Report (MMWR). The cases were confirmed from Aug 4, 2010, to Sep 26, 2011, and mainly involved children. The median age of patients was 6 years (range, under 1 to 75 years), with 66% younger than 10 and 63% female. Of the 56 patients interviewed, 36 (64%) reported turtle exposure, and of 15 patients who could recall the turtle type, 14 identified turtles too small to be legally sold. (Turtles with shells less than 4 inches long are illegal to sell in the United States.) Five samples of turtle tank water from patient homes tested positive for the outbreak strain, which is S enterica serotype "Paratyphi B var. L (+) tartrate +." The authors conclude, "Despite a 30-year ban on small turtles, this ongoing outbreak suggests that ban enforcement efforts, as well as public education efforts, have not been fully successful and should be examined.
Feb 3 MMWR notice

Outbreak Campylobacter confirmed in raw milk on Pennsylvania farm
Two unopened containers of unpasteurized (raw) milk on a Pennsylvania farm implicated in an outbreak of Campylobacter illnesses have tested positive for the outbreak strain, the Maryland Department of Health and Mental Hygiene (DHMH) announced yesterday. In addition, the number of confirmed cases has grown to 23 (19 in Pennsylvania and 4 in Maryland), up from 6 reported in the last DHMH update on Jan 27. The cases have been linked by Pennsylvania and Maryland public health officials to The Family Cow dairy farm in Chambersburg, Pa. Farm owners said that tests of three milk samples by a private firm they hired showed no pathogens, according to a Food Safety News (FSN) story today. Results of tests by Pennsylvania officials have not yet been released. Authorities urge anyone who bought milk from the farm since Jan 1 to dispose of it.
Feb 1 Maryland DHMH update
Feb 2 FSN story

Norovirus, Staph lead list of hospital outbreak pathogens
Norovirus and Staphylococcus aureus led the list of outbreak-causing pathogens in US hospitals in 2008 and 2009, according to a study in the current American Journal of Infection Control. A research team surveyed 822 members of the Association for Professionals in Infection Control and Epidemiology (APIC) who work in US hospitals, 25% of whom had investigated at least one outbreak during the 2 years. They found that four pathogens caused nearly 60% of the outbreaks: norovirus (18.2%), S aureus (17.5%), Acinetobacter (13.7%), and Clostridium difficile (10.3%). The average number of confirmed cases per outbreak was 10.1, and the average outbreak duration was 58.4 days. Only 28.4% of outbreaks required outside assistance for the investigation. The most common outbreak location was a medical/surgical unit (25.7%), followed by a surgical unit (13.9%).
February Am J Infect Control abstract
Jan 31 press release on the study

Scientists find guinea pigs to be good influenza B research models
The guinea pig may prove a good model for studying how influenza B viruses behave in humans, researchers from Mount Sinai School of Medicine in New York said in a study published yesterday in the Journal of Virology. The team demonstrated that influenza B viruses—which mutate more slowly than type A viruses and are less genetically diverse—can replicate in the upper respiratory tract of guinea pigs and transmit with 100% efficiency between inoculated animals and those never before exposed to the strains, through both contact and non-contact routes. They also found that transmission is enhanced at colder temperatures, as is true for influenza A. "We therefore present, for the first time, a small animal model in which to study the underlying mechanisms of influenza B virus transmission," they conclude.
Feb 1 J Virol abstract

Field study of ticks produces Lyme risk map
An extensive field study involving 80 tick-gatherers at 304 sites has produced a detailed map of Lyme disease risk in the United States, according to a report in the American Journal of Tropical Medicine and Hygiene. Scientists found high infection risk confined primarily to the Northeast, Mid-Atlantic, and Upper Midwest, and the map details areas of highest concern. "There has been a lot of discussion of whether Lyme disease exists outside of the Northeast and the upper Midwest, but our sampling of tick populations at hundreds of sites suggests that any diagnosis of Lyme disease in most of the South should be put in serious doubt, unless it involves someone who has traveled to an area where the disease is common," said lead author Maria A. Diuk-Wasser, PhD, of the Yale School of Public Health, in a press release from the American Society of Tropical Medicine and Hygiene (ASTMH). The map was developed through a cooperative agreement with the CDC, which is seeking a better understanding of Lyme disease risk to public health.
February Am J Trop Med Hyg study
Feb 1 ASTMH press release

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