William E. Keene

We investigated a norovirus outbreak (genotype GII.2) affecting 9 members of a soccer team. Illness was associated with touching a reusable grocery bag or consuming its packaged food contents (risk difference, 0.636; P < .01). By polymerase chain reaction, GII norovirus was recovered from the bag, which had been stored in a bathroom used before the outbreak by a person with norovirus-like illness. Airborne contamination of fomites can lead to subsequent point-source outbreaks. When feasible, we recommend dedicated bathrooms for sick persons and informing cleaning staff (professional or otherwise) about the need for adequate environmental sanitation of surfaces and fomites to prevent spread.

Research from JAMA — Outbreak of Pseudomonas aeruginosa Infections Caused by Commercial Piercing of Upper Ear Cartilage — ContextSporadic infections following ear piercing are well documented, but common-source outbreaks are rarely recognized.ObjectiveTo investigate reports of auricular chondritis subsequent to commercial ear piercing.Design, Setting, and SubjectsOutbreak investigation by Oregon public health agencies, including cohort study of persons pierced at a jewelry kiosk in August-September 2000, environmental sampling, and molecular subtyping of isolates. Confirmed cases had Pseudomonas aeruginosa cultured from ear wounds. Suspected cases had signs and symptoms of external ear infection, including drainage of pus or blood for at least 14 days.Main Outcome MeasuresRisk factors for infection and comparison of bacterial isolates by molecular subtyping.ResultsFrom 186 piercings in 118 individuals, we identified 7 confirmed P aeruginosa infections and 18 suspected infections. Confirmed cases were 10 to 19 years old. Most were initially treated with antibiotics ineffective against Pseudomonas. Four were hospitalized, 4 underwent incision and drainage surgeries (1 as an outpatient), and several were cosmetically deformed. Upper ear cartilage piercing was more likely to result in either confirmed or suspected infection than was lobe piercing (confirmed: RR undefined, P<.001; suspected: RR, 3.6; 95% confidence interval, 1.5-8.5). All persons with confirmed infections had their ear cartilage pierced with an open, spring-loaded piercing gun. Patient isolates were indistinguishable by molecular subtyping, and matching isolates were recovered from a disinfectant bottle and nearby sink. At least 1 worker admitted sometimes spraying the disinfectant on the ear studs before piercing.ConclusionsEar cartilage piercing is inherently more risky than lobe piercing. Clinicians should respond aggressively to potential auricular chondritis and consider Pseudomonas a possible cause pending culture results.

Based on in vitro data, the U.S. Food and Drug Administration recommends chemical disinfection of raw sprout seeds to reduce enteric pathogens contaminating the seed coats. However, little is known about the effectiveness of decontamination at preventing human disease. In 1999, an outbreak of Salmonella enterica serotype Mbandaka occurred in Oregon, Washington, Idaho, and California. Based on epidemiologic and pulsed-field gel electrophoresis evidence from 87 confirmed cases, the outbreak was linked to contaminated alfalfa seeds grown in California’s Imperial Valley. Trace-back and trace-forward investigations identified a single lot of seeds used by five sprout growers during the outbreak period. Cases of salmonellosis were linked with two sprout growers who had not employed chemical disinfection; no cases were linked to three sprout growers who used disinfection. This natural experiment provides empiric evidence that chemical disinfection can reduce the human risk for disease posed by contaminated seed sprouts.