Acute hepatitis B outbreaks in 2 skilled nursing facilities and possible sources of transmission: North Carolina, 2009-2010.

OBJECTIVE: Acute hepatitis B virus (HBV) infections have been reported in long-term care facilities (LTCFs), primarily associated with infection control breaks during assisted blood glucose monitoring. We investigated HBV outbreaks that occurred in separate skilled nursing facilities (SNFs) to determine factors associated with transmission. DESIGN: Outbreak investigation with case-control studies. SETTING: Two SNFs (facilities A and B) in Durham, North Carolina, during 2009-2010. PATIENTS: Residents with acute HBV infection and controls randomly selected from HBV-susceptible residents during the outbreak period. METHODS: After initial cases were identified, screening was offered to all residents, with repeat testing 3 months later for HBV-susceptible residents. Molecular testing was performed to assess viral relatedness. Infection control practices were observed. Case-control studies were conducted to evaluate associations between exposures and acute HBV infection in each facility. RESULTS: Six acute HBV cases were identified in each SNF. Viral phylogenetic analysis revealed a high degree of HBV relatedness within, but not between, facilities. No evaluated exposures were significantly associated with acute HBV infection in facility A; those associated with infection in facility B (all odds ratios >20) included injections, hospital or emergency room visits, and daily blood glucose monitoring. Observations revealed absence of trained infection control staff at facility A and suboptimal hand hygiene practices during blood glucose monitoring and insulin injections at facility B. CONCLUSIONS: These outbreaks underscore the vulnerability of LTCF residents to acute HBV infection, the importance of surveillance and prompt investigation of incident cases, and the need for improved infection control education to prevent transmission.

Serologic testing for protection against hepatitis B virus infection among students at a health sciences university in the United States.

OBJECTIVE: To evaluate hepatitis B vaccination coverage and documentation of vaccine-induced immunity. DESIGN: Retrospective cohort analysis. SETTING: Graduate school in the United States with programs in osteopathic medicine, dentistry, and allied health. METHODS: Data collected included demographics, dates of hepatitis B vaccine doses, and postvaccination concentrations of antibody to hepatitis B surface antigen (anti-HBs), with dates. The proportions of students with anti-HBs of 10 IU/L or more by demographics, age at vaccination, interval since completion of the primary series, and response to additional vaccine doses were compared. RESULTS: Of 3,452 students who matriculated during 2004-2009, 2,643 had complete data; 2,481 (93.9%) received 3 primary doses. Most were women (64.6%), US-born (85.6%), and white (63.2%); median age at receipt of the primary series was 14.5 years (interquartile range, 11.6-20.2 years) and at postvaccination testing was 23.2 years (interquartile range, 22.1-24.8 years). Of those who received 3 primary doses, 2,306 (92.9%) had an anti-HBs postvaccination concentration of 10 IU/L or more. Younger age at vaccination and longer time interval from vaccination to anti-HBs testing were associated with a postvaccination concentration of less than 10 IU/L (P< .001 and P = .0185, respectively, Cochran-Armitage test for trend). Almost all students (98.2%) who initially had less than 10 IU/L of anti-HBs, but then received at least 1 additional dose, had a follow-up anti-HBs concentration of 10 IU/L or more. CONCLUSIONS: Almost all students had serologic evidence of protection against hepatitis B virus infection; most were vaccinated as adolescents and were tested more than 10 years after vaccination. Among students with anti-HBs concentrations of less than 10 IU/L, nearly all had 10 IU/L or more after at least 1 additional vaccine dose.

Hepatitis B vaccination of susceptible elderly residents of long term care facilities during a hepatitis B outbreak.

Protection of older persons, particularly those with diabetes, against hepatitis B virus (HBV) infection is of growing concern because of increased reports of outbreaks among long-term care facility residents receiving assisted blood glucose monitoring. We evaluated hepatitis B vaccine immunogenicity among residents immunized in response to two such outbreaks in skilled nursing facilities during June 2009-July 2010. One hundred forty-eight (71%) of 209 residents were found to be susceptible to HBV infection. Of 105 patients who began a vaccination series with Twinrix(®) (0-, 1-, 6-month dosing), 86 (82%) completed the series and postvaccination testing. Of these, most were elderly (median age 79.5 years; range 45-101), female (56%), and African-American (51%). Twenty-nine (34%) vaccinated residents had post-vaccination hepatitis B surface antibody levels ≥10 mIU/ml. There were no significant differences in vaccine response by age, gender, race, diabetes status, body mass index, or current smoking status. Our findings indicate that a low proportion of skilled nursing facility residents achieved a seroprotective response after hepatitis B vaccination.