[Show abstract][Hide abstract] ABSTRACT: Little is known about duration of protection after the infant primary series of hepatitis B (HB) vaccine in settings of low HB endemicity. This study sought to determine the proportion of adolescents immunized as infants who had protective titers of antibody to hepatitis B surface antigen (anti-HBs) before and after a challenge dose of vaccine.METHODS: US-born 16- through 19-year-olds who received a recombinant HB vaccine 3-dose series initiated within 7 days of birth (group 1) or at ≥4 weeks of age (group 2) and completed by 12 months of age were enrolled. Participants had serologic testing before and 2 weeks after randomization to receive a challenge dose of 10 µg or 20 µg of Engerix-B. Baseline and postchallenge levels of anti-HBs were compared by group, challenge dosage, and demographic and behavioral characteristics.RESULTS: At baseline, 24% had protective anti-HBs levels of ≥10 IU/mL; 92% achieved protective levels after challenge dose. Although group 1 had a lower proportion of seroprotection at baseline, group and challenge dosage were not associated with postchallenge proportion of seroprotection. Being in group 2, higher test dosage, higher baseline geometric mean titer, and nonwhite race were associated with significantly higher geometric mean titer after challenge dose.CONCLUSIONS: More than 90% of study participants immunized against HB as infants exhibited a seroprotective response to a challenge dose of vaccine. Duration of protection from the primary infant HB vaccine series extended through the adolescent years in the setting of low HB endemicity.
[Show abstract][Hide abstract] ABSTRACT: Hepatitis B virus (HBV) infection is widely prevalent among racial and ethnic minorities in the United States however few data have been available regarding HBV testing and referral to care for these populations. Using survey data collected in 2009-2010 from the Racial and Ethnic Approaches to Community Health (REACH) across the US, we assessed rates and determinants of hepatitis B testing and access to care in 28 minority communities in the United States. Of 53,896 respondents, 21,129 (39.2%) reported having been tested for hepatitis B. Of the 1,235 who reported testing positive, 411 (33.3%) reported currently receiving specialty care. After controlling for demographic and socio-economic characteristics, the likelihood of having been tested for hepatitis B and receiving care if infected was higher among males, non-English speaking persons,and those having health insurance compared to their counterparts. Compared to college graduates, respondents without a college education were less likely to get tested for hepatitis B. These data indicate that more than half of racial/ethnic minority persons in these communities had not been tested for hepatitis B, and only about one half of those who tested positive had ever received treatment. More state and federal efforts are needed to screen racial/ethnic minority, especially foreign born persons for HBV and link those with infection to care. (HEPATOLOGY 2013.) (HEPATOLOGY 2013.).
[Show abstract][Hide abstract] ABSTRACT: On January 30, 2009, nursing staff at a military hospital in Texas reported that single-patient use insulin pens were used on multiple patients. An investigation was initiated to determine if patient-to-patient bloodbome transmission occurred from the practice. Human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) testing was offered to patients hospitalized from August 2007 to January 2009 and prescribed insulin pen injections. Virus from HCV-infected patients' sera was sequenced and compared for relatedness. An anonymous survey was administered to nurses. Of 2,113 patients prescribed insulin pen injections, 1,501 (71%) underwent testing; 6 (0.4%) were HIV positive, 6 (0.4%) were hepatitis B surface antigen positive, and 56 (3.7%) had HCV antibody. No viral sequences from 10 of 28 patients with newly diagnosed and 12 of 28 patients with preexisting HCV infection were closely related. Of 54 nurses surveyed, 74% reported being trained on insulin pen use, but 24% believed nurses used insulin pens on more than one patient. We found no clear evidence of bloodborne pathogen transmission. Training of hospital staff on correct use of insulin pens should be prioritized and their practices evaluated. Insulin pens should be more clearly labeled for single-patient use.
Military medicine 08/2012; 177(8):930-8. · 0.77 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Natural cross-protective immunity is induced after spontaneous clearance of primary hepatitis C virus (HCV) infection. Although this suggests that effective prophylactic vaccines against HCV are possible, there are still several areas that require further study. Current data indicate that, at best, vaccine-induced immunity may not completely prevent HCV infection but rather prevent persistence of the virus. However, this may be an acceptable goal, because chronic persistence of the virus is the main cause of pathogenesis and the development of serious liver conditions. Therapeutic vaccine development is also highly challenging; however, strategies have been pursued in combination with current or new treatments in an effort to reduce the costs and adverse effects associated with antiviral therapy. This review summarizes the current state of HCV vaccines and the challenges faced for future development and clinical trial design.
[Show abstract][Hide abstract] ABSTRACT: The impact of hepatitis C virus (HCV) infection on health and medical care in the United States is a major problem for infectious disease physicians. Although the incidence of HCV infection has declined markedly in the past 2 decades, chronic infection in 3 million or more residents now accounts for more disease and death in the United States than does human immunodeficiency virus (HIV)/AIDS. Current trends in the epidemiology of HCV infection include an apparent increase in young, often suburban heroin injection drug users who initiate use with oral prescription opioid drugs; infections in nonhospital healthcare (clinic) settings; and sexual transmission among HIV-infected persons. Infectious disease physicians will increasingly have the responsibility of diagnosing and treating HCV patients. An understanding of how these patients were infected is important for determining whom to screen and treat.
[Show abstract][Hide abstract] ABSTRACT: 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.
[Show abstract][Hide abstract] ABSTRACT: Persistence of seropositivity conferred by hepatitis A vaccine administered to children <2 years of age is unknown and passively transferred maternal antibodies to hepatitis A virus (maternal anti-HAV) may lower the infant's immune response to the vaccine. One hundred ninety-seven infants and young children were randomized into three groups to receive a two-dose hepatitis A vaccine: group 1 at 6 and 12 months, group 2 at 12 and 18 months, and group 3 at 15 and 21 months of age. Within each group, infants were randomized by maternal anti-HAV status. Anti-HAV levels were measured at 1 and 6 months and at 3, 5, 7, and 10 years after the second dose of hepatitis A vaccination. Children in all groups had evidence of seroprotection (>10 mIU/mL) at 1 month after the second dose. At 10 years, all children retained seroprotective anti-HAV levels except for only 7% and 11% of children in group 1 born to anti-HAV-negative and anti-HAV-positive mothers, respectively, and 4% of group 3 children born to anti-HAV-negative mothers. At 10 years, children born to anti-HAV-negative mothers in group 3 had the highest geometric mean concentration (GMC) (97 mIU/mL; 95% confidence interval, 71-133 mIU/mL) and children born to anti-HAV-positive mothers in group 1 had the lowest GMC (29 mIU/mL; 95% confidence interval, 20-40 mIU/mL). Anti-HAV levels through 10 years of age correlated with initial peak anti-HAV levels (tested at 1 month after the second dose). CONCLUSION: The seropositivity induced by hepatitis A vaccine given to children <2 years of age persists for at least 10 years regardless of presence of maternal anti-HAV.
[Show abstract][Hide abstract] ABSTRACT: The long-term duration of recombinant hepatitis B vaccine-induced immunity among persons vaccinated starting at birth is still not well understood. Waning of vaccine-induced immunity could leave young adults at risk of hepatitis B virus infection due to behavioral or occupational exposures. We followed a cohort of children immunized starting at birth with a 3-dose regimen of recombinant hepatitis B vaccine (5 mcg, 2.5 mcg, 2.5 mcg). They were challenged with a booster dose of the hepatitis B vaccine 10 and 15 years after vaccination to assess anamnestic response as a measure of persistence of protection. Among 108 participants who had lost protective antibody levels against hepatitis B, the majority (>70%) had an anamnestic response to the booster dose; response rates did not decline significantly between 10 and 15 years follow-up periods. A high antibody concentration following primary vaccination was independently associated with an anamnestic response later on in life. Nonetheless, ~20-30% of participants were unable to mount an immune response after boosting. Hepatitis B revaccination might be required for persons vaccinated starting at birth if opportunities for hepatitis B virus exposure exist. Future vaccine recommendations should be based on studies ascertaining protection against clinically significant disease.
[Show abstract][Hide abstract] ABSTRACT: A high prevalence of hepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections have been reported among persons with severe mental illness. In October, 2009, the Cook County Department of Public Health (CCDPH) initiated an investigation following notification of a cluster of HBV infections among mentally ill residents at a long term care facility (LTCF).
LTCF staff were interviewed and resident medical records were reviewed. Residents were offered testing for HBV, HCV, and HIV. Serum specimens from residents diagnosed with HBV or HIV infection were sent to the Centers for Disease Control and Prevention (CDC) for analysis.
Eleven newly diagnosed HBV infections were identified among mentally ill residents at the LTCF. Of these 11 infections, 4 serum specimens were available for complete HBV genome sequencing; all 4 genomes were found to be closely related. Four newly diagnosed HIV infections were identified within this same population. Upon molecular analysis, 2 of 4 HIV sequences from these new infections were found to be nearly identical and formed a tight phylogenetic cluster.
HBV and HIV transmission was identified among mentally ill residents of this LTCF. Continued efforts are needed to prevent bloodborne pathogen transmission among mentally ill residents in LTCFs.
PLoS ONE 01/2012; 7(8):e43252. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Hepatitis E is caused by the hepatitis E virus (HEV), the major etiologic agent of enterically transmitted non-A hepatitis worldwide. HEV is responsible for major outbreaks of acute hepatitis in developing countries, especially in many parts of Africa and Asia. The HEV is a spherical, non-enveloped, single-stranded, positive sense RNA virus that is approximately 32 nm to 34 nm in diameter and is the only member in the family Hepeviridae and genus Hepevirus. There are four distinct genotypes of HEV (genotypes 1-4). While genotype 1 is predominantly associated with large epidemics in developing countries, genotype 3 has recently emerged as a significant pathogen in developed countries. The clinical manifestations and the laboratory abnormalities of hepatitis E are not distinguishable from that caused by other hepatitis viruses. However, high mortality among pregnant women particularly during the third trimester distinguishes HEV from other causes of acute viral hepatitis. Specific etiologic diagnosis among infected cases can be made by serological testing or detection of viral nucleic acid by reverse transcription polymerase chain reaction. Although there are vaccine candidates that had been shown to be safe and efficacious in clinical trials, none are approved currently for use. There is no specific therapy for acute hepatitis E as treatment remains supportive.
World journal of hepatology. 12/2011; 3(12):285-91.
[Show abstract][Hide abstract] ABSTRACT: Hepatitis A vaccination has dramatically reduced the incidence of hepatitis A virus (HAV) infection, but new infections continue to occur. To identify human genetic variants conferring a risk for HAV infection among the three major racial/ethnic populations in the United States, we assessed associations between 67 genetic variants (single nucleotide polymorphisms [SNPs]) among 31 candidate genes and serologic evidence of prior HAV infection using a population-based, cross-sectional study of 6,779 participants, including 2,619 non-Hispanic whites, 2,095 non-Hispanic blacks, and 2,065 Mexican Americans enrolled in phase 2 (1991-1994) of the Third National Health and Nutrition Examination Survey. Among the three racial/ethnic groups, the number (weighted frequency) of seropositivity for antibody to HAV was 958 (24.9%), 802 (39.2%), and 1540 (71.5%), respectively. No significant associations with any of the 67 SNPs were observed among non-Hispanic whites or non-Hispanic blacks. In contrast, among Mexican Americans, variants in two genes were found to be associated with an increased risk of HAV infection: TGFB1 rs1800469 (adjusted odds ratio [OR], 1.38; 95% confidence interval [CI], 1.14-1.68; P value adjusted for false discovery rate [FDR-P] = 0.017) and XRCC1 rs1799782 (OR, 1.57; 95% CI, 1.27-1.94; FDR-P = 0.0007). A decreased risk was found with ABCB1 rs1045642 (OR, 0.79; 95% CI, 0.71-0.89; FDR-P = 0.0007). Conclusion: Genetic variants in ABCB1, TGFB1, and XRCC1 appear to be associated with susceptibility to HAV infection among Mexican Americans. Replication studies involving larger population samples are warranted.
[Show abstract][Hide abstract] ABSTRACT: During the past decade, in the United States, an increasing number of hepatitis B outbreaks have been reported in assisted living facilities (ALFs) as a result of breaches in infection control practices. We evaluated the seroprotection rates conferred by hepatitis B vaccine among older adults during a response to an outbreak that occurred in multiple ALFs and assessed the influence of demographic and clinical factors on vaccine response.
Residents were screened for hepatitis B and C infection prior to vaccination and susceptible residents were vaccinated against hepatitis B with one dose of 20 μg Engerix-B™ (GSK) given at 0, 1, and 4 months. Blood samples were collected 80-90 days after the third vaccine dose to test for anti-HBs levels.
Of the 48 residents who had post-vaccination blood specimens collected after the third vaccine dose, 16 (33.3%) achieved anti-HBs concentration ≥10 mIU/mL. Age was a significant determinant of seroprotection with rates decreasing from 88% among persons aged ≤60 years to 12% among persons aged ≥90 years (p=0.001). Geometric mean concentrations were higher among non-diabetic than diabetic residents, however, the difference was not statistically significant (5.1 vs. 3.8 mIU/mL, p=0.7).
These findings highlight that hepatitis B vaccination is of limited effectiveness when administered to older adults. Improvements in infection control and vaccination at earlier ages might be necessary to prevent spread of infection in ALFs.
[Show abstract][Hide abstract] ABSTRACT: Locally acquired hepatitis E infection is increasingly being observed in industrialized countries. We report 2 cases of autochthonous acute hepatitis E in the United States. Hepatitis E virus genotype 3a related to US-2 and swine hepatitis E virus strains was isolated from one of the patients, indicating potential food-borne or zoonotic transmission.
[Show abstract][Hide abstract] ABSTRACT: Knowledge of the genotypic distribution of hepatitis B virus (HBV) facilitates epidemiologic tracking and surveillance of HBV infection as well as prediction of its disease burden. In the United States, HBV genotyping studies have been conducted for chronic but not acute hepatitis B.
Serum samples were collected from patients with acute hepatitis B cases reported from the 6 counties that participated in the Sentinel Counties Study of Acute Viral Hepatitis from 1999 through 2005. Polymerase chain reaction followed by nucleotide sequencing of a 435-base pair segment of the HBV S gene was performed, and the sequences were phylogenetically analyzed.
Of 614 patients identified with available serum samples, 75% were infected with genotype A HBV and 18% were infected with genotype D HBV. Thirty-two percent of genotype A sequences constituted a single subgenotype A2 cluster. The odds of infection with genotype A (vs with genotype D) were 5 times greater among black individuals than among Hispanic individuals (odds ratio [OR], 5; 95% confidence interval [CI], 2.3-10.7). The odds of infection with genotype A were 49, 8, and 4 times greater among patients from Jefferson County (Alabama), Pinellas County (Florida), and San Francisco (California), respectively, than among those living in Denver County (Colorado). Genotype A was less common among recent injection drug users than it was among non-injection drug users (OR, 0.2; 95% CI, 0.1-0.4).
HBV genotype distribution was significantly associated with ethnicity, place of residence, and risk behavior.
[Show abstract][Hide abstract] ABSTRACT: Effective measures exist to prevent health care-associated hepatitis B virus (HBV) transmission, yet outbreaks continue to occur. In 2008, the Los Angeles County Department of Public Health identified an outbreak of HBV infections among psychiatric long-term care facility residents.
Residents underwent HBV serologic testing and were classified as acutely infected, chronically infected, susceptible, or immune. Persons residing in the facility during 2008 were enrolled in a retrospective cohort study to identify risk factors for acute HBV infection. We assessed infection control practices at the facility.
Nine of 81 residents (11%) enrolled in the cohort study had acute HBV infection. Five of 15 residents (33%) undergoing podiatric care on a single day subsequently developed acute infection (rate ratio, 4.33; 95% confidence interval, 1.18-15.92). Infection control observations of the consulting podiatrist revealed opportunities for cross-contamination of instruments with blood. Other potential health care and behavioral modes of transmission were identified as well. Residents were offered HBV vaccination, and infection control recommendations were implemented by the podiatrist and facility.
Of the multiple potential transmission modes identified, exposure to HBV during podiatry was likely the dominant mode in this outbreak. Long-term care facilities should ensure compliance with infection control standards among staff and consulting health care providers.
American journal of infection control 08/2011; 40(1):16-21. · 3.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Without intervention, up to 25% of individuals chronically infected with hepatitis B virus (HBV) die of late complications, including cirrhosis and liver cancer. The United States, which in 1991 implemented a strategy to eliminate HBV transmission through universal immunization, is a country of low prevalence. Approximately 3,000-5,000 U.S.-acquired cases of chronic hepatitis B have occurred annually since 2001. Many more chronically infected persons migrate to the United States yearly from countries of higher prevalence. Although early identification of chronic HBV infection can reduce the likelihood of transmission and late complications, immigrants are not routinely screened for HBV infection during or after immigration.
To estimate the number of imported cases of chronic hepatitis B, we multiplied country-specific prevalence estimates by the yearly number of immigrants from each country during 1974-2008.
During 1974-2008, 27.9 million immigrants entered the U.S. Sixty-three percent were born in countries of intermediate or high chronic hepatitis B prevalence (range 2%-31%). On average, an estimated 53,800 chronic hepatitis B cases were imported to the U.S. yearly from 2004 through 2008. The Philippines, China, and Vietnam contributed the most imported cases (13.4%, 12.5%, and 11.0%, respectively). Imported cases increased from an estimated low of 105,750 during the period 1974-1977 to a high of 268,800 in 2004-2008.
Imported chronic hepatitis B cases account for approximately 95% of new U.S. cases. Earlier case identification and management of infected immigrants would strengthen the U.S. strategy to eliminate HBV transmission, and could delay disease progression and prevent some deaths among new Americans.
PLoS ONE 01/2011; 6(12):e27717. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Folate is a source of one-carbons necessary for DNA methylation, a critical epigenetic modification necessary for genomic structure and function. The use of supplemental folic acid is widespread however; the potential influence on DNA methylation is unclear. We measured global DNA methylation using DNA extracted from samples from a population-based, double-blind randomized trial of folic acid supplementation (100, 400, 4000 µg per day) taken for 6 months; including a 3 month post-supplementation sample. We observed no changes in global DNA methylation in response to up to 4,000 µg/day for 6 months supplementation in DNA extracted from uncoagulated blood (approximates circulating blood). However, when DNA methylation was determined in coagulated samples from the same individuals at the same time, significant time, dose, and MTHFR genotype-dependent changes were observed. The baseline level of DNA methylation was the same for uncoagulated and coagulated samples; marked differences between sample types were observed only after intervention. In DNA from coagulated blood, DNA methylation decreased (-14%; P<0.001) after 1 month of supplementation and 3 months after supplement withdrawal, methylation decreased an additional 23% (P<0.001) with significant variation among individuals (max+17%; min-94%). Decreases in methylation of ≥25% (vs. <25%) after discontinuation of supplementation were strongly associated with genotype: MTHFR CC vs. TT (adjusted odds ratio [aOR] 12.9, 95%CI 6.4, 26.0). The unexpected difference in DNA methylation between DNA extracted from coagulated and uncoagulated samples in response to folic acid supplementation is an important finding for evaluating use of folic acid and investigating the potential effects of folic acid supplementation on coagulation.
PLoS ONE 01/2011; 6(12):e28144. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Performance of the BED assay in estimating HIV-1 incidence has previously been evaluated by using longitudinal specimens from persons with incident HIV infections, but questions remain about its accuracy. We sought to assess its performance in three longitudinal cohorts from Thailand where HIV-1 CRF01_AE and subtype B' dominate the epidemic.
BED testing was conducted in two longitudinal cohorts with only incident infections (a military conscript cohort and an injection drug user cohort) and in one longitudinal cohort (an HIV-1 vaccine efficacy trial cohort) that also included long-term infections.
Incidence estimates were generated conventionally (based on the number of annual serocoversions) and by using BED test results in the three cohorts. Adjusted incidence was calculated where appropriate.
For each longitudinal cohort the BED incidence estimates and the conventional incidence estimates were similar when only newly infected persons were tested, whether infected with CRF01_AE or subtype B'. When the analysis included persons with long-term infections (to mimic a true cross-sectional cohort), BED incidence estimates were higher, although not significantly, than the conventional incidence estimates. After adjustment, the BED incidence estimates were closer to the conventional incidence estimates. When the conventional incidence varied over time, as in the early phase of the injection drug user cohort, the difference between the two estimates increased, but not significantly.
Evaluation of the performance of incidence assays requires the inclusion of a substantial number of cohort-derived specimens from individuals with long-term HIV infection and, ideally, the use of cohorts in which incidence remained stable. Appropriate adjustments of the BED incidence estimates generate estimates similar to those generated conventionally.
PLoS ONE 01/2011; 6(3):e14748. · 3.53 Impact Factor