Two outbreaks of severe respiratory disease in nursing homes associated with rhinovirus.

OBJECTIVES: To characterize illness and identify the etiology for two nursing home outbreaks of respiratory illness. DESIGN: Multisite outbreak investigations; cohort. SETTING: Two nursing homes in Pennsylvania. PARTICIPANTS: Facility A residents (n = 170), Facility B residents (n = 124), and employees (n = 91). MEASUREMENTS: Medical records for Facility A and B residents were reviewed, and employees from Facility B self-administered a questionnaire to identify risk factors for illness. Serological, oropharyngeal, and nasopharyngeal specimens were collected for both outbreaks, and testing for respiratory pathogens was performed. RESULTS: In Facility A, 40 (24%) of 170 residents were identified with respiratory illness; 13 (33%) case-patients had radiographically confirmed pneumonia, 15 (38%) were taken to a hospital, and two (5%) died. Of 10 specimens collected from symptomatic Facility A case-patients, four (40%) tested positive using reverse transcription polymerase chain reaction for rhinovirus. In Facility B, 77 (62%) of 124 residents had respiratory illness, and 40 (52%) had radiographically confirmed pneumonia; 12 (16%) case-patients were hospitalized, and five (6%) died. Of 19 respiratory specimens collected from symptomatic Facility B case-patients, six (32%) were positive for rhinovirus; one was from an employee. Five (50%) of 10 rhinovirus-positive cases in both outbreaks had clinical and radiographic evidence of pneumonia. CONCLUSION: These investigations suggest that rhinoviruses may be an underrecognized cause of respiratory outbreaks in nursing homes, capable of causing pneumonia and perhaps death.

Necrotizing enterocolitis associated with clostridium perfringens type A in previously healthy north american adults.

BACKGROUND: Necrotizing enteritis associated with Clostridium perfringens type C ("pigbel") is a well-known syndrome in severely protein-deprived populations in the Pacific. It is exceedingly rare in the developed world. C perfringens type A is a common cause of acute gastroenteritis and, in a handful of infections, has been reported in association with a syndrome resembling necrotizing enteritis. STUDY DESIGN: This study includes a case series and literature review. Charts and autopsy reports from four patients with adult necrotizing enterocolitis (ANEC) were reviewed. C perfringens isolates were subtyped by mouse bioassay and pulsed-field gel electrophoresis. Fixed tissue specimens were tested with an anticlostridial antibody using an immunohistochemical assay. RESULTS: Between 2000 and 2003, ANEC developed in four previously healthy men; three died. The small bowel was affected in three patients and the colon in two patients. Portal or mesenteric vein thrombosis occurred in three patients. C perfringens type A was isolated from three patients and immunohistochemical assay demonstrated clostridial antigens limited to affected areas of the intestine of all four. The nonculture positive patient had a strong epidemiologic link to one of the others, and a compatible clinical course. C perfringens of the same pulsed-field gel electrophoresis-defined molecular subtyped was isolated from stool samples of one patient, his wife, and food from a restaurant they patronized. CONCLUSIONS: ANEC associated with C perfringens type A infection occurred in four North American adults. Culture for C perfringens type A should be performed in cases of ANEC. Alternative tests such as immunohistochemical assay were diagnostically useful. Additional research might uncover virulence factors, host factors, and the burden of disease in the population.

A limited measles outbreak in a highly vaccinated US boarding school.

OBJECTIVES: We investigated a measles outbreak that began in March 2003 in a Pennsylvania boarding school with >600 students to identify all cases, including the source; implement outbreak control measures; and evaluate vaccine effectiveness. METHODS: Measles was suspected in any person at the school with a generalized rash and fever during March 21 to May 28, 2003 and investigated with serologic testing. We reviewed vaccination history from school records and conducted a survey to determine country of measles vaccination. Vaccine effectiveness was calculated using the cohort method. RESULTS: We identified 9 laboratory-confirmed cases at the school: 8 students and 1 staff member. Among them, 2 had never received any doses of measles-containing vaccine (MCV), 1 received 1 dose of MCV, and 6 received 2 doses of MCV. Three of the 6 who received 2 doses of MCV received both doses outside the United States. The source case had been infected in Lebanon. Two laboratory-confirmed spread cases were identified in New York City. Measles virus of genotype D4 was isolated in cases from the school and New York City. Of the 663 students in the school, 8 (1.2%) had never received any doses of MCV, 26 (3.9%) had received 1 dose, and 629 (94.9%) had received 2 doses before the outbreak. Vaccine effectiveness among students who had received 2 doses of MCV was 98.6%. However, students who received both doses outside the United States had a higher attack rate (3 of 75) than those who received both doses in the United States (3 of 509; rate ratio: 6.8; 95% confidence interval: 1.4-33.0). CONCLUSIONS: This is the largest measles outbreak to occur in a school in the United States since 1998, but it was limited to only 9 cases in a boarding school with >600 students. The limited extent of this outbreak highlights the high level of population immunity achieved in the United States through widespread implementation of a 2-dose measles-mumps-rubella vaccination strategy in school-aged children. States and schools should continue to enforce strictly the 2-dose measles-mumps-rubella vaccination requirement and, in an outbreak setting, consider revaccinating students who received measles vaccine outside of the United States. Continued vigilance by health care providers is needed to recognize measles cases.