7�C137) or injected medications ([RR], 3.0; 95% [CI], 1.2�C7.6) compared with residents who were not exposed to these procedures (Table 2). Stratifying injected medications by receipt of AMBG revealed that all 7 acutely infected residents who received injected medications also had received AMBG (Table 2). Acute HBV infection developed among 12 (92%) of view more 13 residents who received AMBG, compared with 2 (3%) of 75 residents who did not (RR = 35; 95% CI, 8.7, 137). Table 2 Assessment of Assisted Living Facility Resident Risk Factors for Hepatitis B Virus Infection, Virginia �C March 2010. HBV DNA Sequence Analysis HBV DNA was available for genotyping and sequencing for 11 (79%) of 14 residents with acute infection and 4 (80%) of 5 residents with chronic infection.

Among these 15 residents, 14 had HBV belonging to subgenotype A2; 1 resident with chronic HBV infection who did not receive blood glucose monitoring had HBV that belonged to A1 subgenotype. Sequences from residents infected with HBV subgenotype A2 formed 2 genetic clusters, each with 99.8�C100% sequence identity (Figure 2). Each cluster was comprised only of specimens from infected persons residing in the same building. Figure 2 Dendrogram Illustrating the Genetic Relatedness of the Hepatitis B Virus* DNA Sequences from Assisted Living Facility? Residents with Acute or Chronic Infections. The building 1 cluster included specimens from 1 resident with chronic infection and 2 residents with acute infection; all 3 received AMBG. The chronically infected resident (whose HBV DNA concentration was 2��109 IU/mL) had resided at the facility for 9 years.

The building 2 cluster included specimens from 2 residents with chronic infection and 9 residents with acute infection. Among these 11, a total of 10 residents had received AMBG, including a chronically infected resident (whose HBV DNA concentration was 1.2��108 IU/mL) who had resided at the facility for 1 year. Outbreak Control Measures VDH provided infection control recommendations both to the ALF and to the Department of Social Services, the agency responsible for licensing and inspecting ALFs in Virginia. VDH worked with ALF staff and licensing inspectors to ensure adoption of single-use, auto-disabling lancets and separate glucose meters for each resident needing AMBG.

VDH offered susceptible residents the hepatitis B vaccine: 61 of 74 (82%) residents agreed to be vaccinated and completed the 3-dose vaccination series. Only one resident who had diabetes was susceptible to HBV infection, and this resident was discharged from the ALF before receiving the third dose of the 3-dose vaccination series. VDH coordinated with Virginia Brefeldin_A Commonwealth University to ensure all HBV-infected residents received clinical follow-up and evaluation of therapy for chronic infection. Discussion Investigation of a single acute HBV infection uncovered an outbreak of 14 acute infections among residents of an ALF.