Publications by authors named "Michael G Bruce"

84 Publications

Global Landscape Review of Serotype-Specific Invasive Pneumococcal Disease Surveillance among Countries Using PCV10/13: The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) Project.

Microorganisms 2021 Apr 2;9(4). Epub 2021 Apr 2.

National Public Health Organisation, 15123 Athens, Greece.

Serotype-specific surveillance for invasive pneumococcal disease (IPD) is essential for assessing the impact of 10- and 13-valent pneumococcal conjugate vaccines (PCV10/13). The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project aimed to evaluate the global evidence to estimate the impact of PCV10/13 by age, product, schedule, and syndrome. Here we systematically characterize and summarize the global landscape of routine serotype-specific IPD surveillance in PCV10/13-using countries and describe the subset that are included in PSERENADE. Of 138 countries using PCV10/13 as of 2018, we identified 109 with IPD surveillance systems, 76 of which met PSERENADE data collection eligibility criteria. PSERENADE received data from most (n = 63, 82.9%), yielding 240,639 post-PCV10/13 introduction IPD cases. Pediatric and adult surveillance was represented from all geographic regions but was limited from lower income and high-burden countries. In PSERENADE, 18 sites evaluated PCV10, 42 PCV13, and 17 both; 17 sites used a 3 + 0 schedule, 38 used 2 + 1, 13 used 3 + 1, and 9 used mixed schedules. With such a sizeable and generally representative dataset, PSERENADE will be able to conduct robust analyses to estimate PCV impact and inform policy at national and global levels regarding adult immunization, schedule, and product choice, including for higher valency PCVs on the horizon.
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http://dx.doi.org/10.3390/microorganisms9040742DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8066045PMC
April 2021

Serotype Distribution of Remaining Pneumococcal Meningitis in the Mature PCV10/13 Period: Findings from the PSERENADE Project.

Microorganisms 2021 Apr 1;9(4). Epub 2021 Apr 1.

Department of Clinical Microbiology, Landspitali-The National University Hospital, Hringbraut, 101 Reykjavik, Iceland.

Pneumococcal conjugate vaccine (PCV) introduction has reduced pneumococcal meningitis incidence. The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project described the serotype distribution of remaining pneumococcal meningitis in countries using PCV10/13 for least 5-7 years with primary series uptake above 70%. The distribution was estimated using a multinomial Dirichlet regression model, stratified by PCV product and age. In PCV10-using sites ( = 8; cases = 1141), PCV10 types caused 5% of cases <5 years of age and 15% among ≥5 years; the top serotypes were 19A, 6C, and 3, together causing 42% of cases <5 years and 37% ≥5 years. In PCV13-using sites ( = 32; cases = 4503), PCV13 types caused 14% in <5 and 26% in ≥5 years; 4% and 13%, respectively, were serotype 3. Among the top serotypes are five (15BC, 8, 12F, 10A, and 22F) included in higher-valency PCVs under evaluation. Other top serotypes (24F, 23B, and 23A) are not in any known investigational product. In countries with mature vaccination programs, the proportion of pneumococcal meningitis caused by vaccine-in-use serotypes is lower (≤26% across all ages) than pre-PCV (≥70% in children). Higher-valency PCVs under evaluation target over half of remaining pneumococcal meningitis cases, but questions remain regarding generalizability to the African meningitis belt where additional data are needed.
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http://dx.doi.org/10.3390/microorganisms9040738DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8066874PMC
April 2021

Stomach Cancer Incidence and Mortality Trends among Circumpolar Nations.

Cancer Epidemiol Biomarkers Prev 2021 May 24;30(5):845-856. Epub 2021 Feb 24.

Cancer Control Research, BC Cancer, British Columbia, Canada.

Background: Stomach cancer incidence and mortality rates are declining across circumpolar nations, but the burden may not be distributed equally across subpopulations, including Indigenous peoples. Our objective was to examine stomach cancer incidence and mortality trends across circumpolar populations.

Methods: Cancer incidence and mortality data from 1999-2016 were obtained from the Canadian Cancer Registry, Canadian Vital Statistics, CDC WONDER, NORDCAN, Northwestern Russian cancer registries, and National Cancer Reports. The direct method was used to calculate 10-year rolling age-standardized incidence and mortality rates to the world (WHO 2000-2025) and 2011 Canadian standard populations. Standardized incidence rate ratios (SRR) were calculated. Data were stratified by sex, year, and region. U.S. data were broken down by race [White; American Indian/Alaska Native (AIAN)]. Race data were not available from non-U.S. cancer registries.

Results: Most populations showed declining incidence and mortality rates over time. Incidence rates among Greenland males and females, Alaska AIAN males and females, and Northern Canadian both sexes were elevated compared with regional counterparts and remained stable. The largest male SRR was observed among Alaska AIAN versus Alaska Whites [SRR = 3.82; 95% confidence interval (95% CI), 2.71-5.37]. The largest female SRR was observed among Alaska AIAN versus Alaska Whites (SRR = 4.10; 95% CI, 2.62-6.43).

Conclusions: Despite stomach cancer incidence and mortality rates declining overall, some northern and Indigenous populations experience elevated and stable incidence and mortality rates.

Impact: There is a need to address disparities observed among circumpolar subpopulations. Given similarities in incidence, mortality, and risk factor prevalence across circumpolar regions, addressing disparities could benefit from coordinated international action.
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http://dx.doi.org/10.1158/1055-9965.EPI-20-1618DOI Listing
May 2021

A High-Risk Subpopulation in the United States Disproportionately Affected by High Rates of Gastric Cancer: The Alaska Native People.

Clin Gastroenterol Hepatol 2021 Mar 26;19(3):620-621. Epub 2020 Nov 26.

Arctic Investigations Program, U.S. Centers for Disease Control and Prevention, Anchorage, Alaska.

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http://dx.doi.org/10.1016/j.cgh.2020.04.087DOI Listing
March 2021

Vaccination Status of Alaska Native Persons With Hepatitis A Virus Infection-Alaska, 1996-2018.

Clin Infect Dis 2021 Jun;72(12):2212-2214

Arctic Investigations Program, Centers for Disease Control and Prevention, Anchorage, Alaska, USA.

Following increases in reported cases of hepatitis A, we assessed the impact of hepatitis A vaccine in Alaska Native persons. During 1996-2018, only 6 cases of hepatitis A were identified, all in unvaccinated adults. Populations can be protected against hepatitis A by achieving sufficient vaccination coverage over time.
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http://dx.doi.org/10.1093/cid/ciaa1102DOI Listing
June 2021

A prospective cohort study of immunogenicity of quadrivalent human papillomavirus vaccination among Alaska Native Children, Alaska, United States.

Vaccine 2020 09 16;38(42):6585-6591. Epub 2020 Aug 16.

Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.

Objective: In the United States, HPV vaccination is routinely recommended at age 11 or 12 years; the series can be started at age 9. We conducted a cohort study to assess long-term immunogenicity of quadrivalent HPV vaccine (4vHPV) in an American Indian/Alaska Native (AI/AN) Indigenous population.

Methods: During 2011-2014, we enrolled AI/AN girls and boys aged 9-14 years, who were vaccinated with a 3-dose series of 4vHPV. Serum specimens were collected at five time points: immediately prior to doses 2 and 3, and at one month, one year, and two years after series completion. Antibody testing was performed using a multiplex virus-like-particle-IgG ELISA for 4vHPV types (HPV 6/11/16/18).

Results: Among 477 children (405 girls/72 boys) completing the 3-dose series, median age at enrollment was 11.2 years. Of the 477, 72 (15%) were tested before dose 2 and 70 (15%) before dose 3. Following series completion, 435 (91%) were tested at one month, 382 (80%) at one year, and 351 (74%) at two years. All tested participants had detectable antibody to 4vHPV types at all time points measured. Geometric mean concentrations (GMCs) for 4vHPV types at one month and two years post-series completion were 269.9 and 32.7 AU/ml for HPV6, 349.3 and 42.9 AU/ml for HPV11, 1240.2 and 168.3 IU/ml HPV16, and 493.2 and 52.2 IU/ml for HPV18. Among children tested after each dose, GMCs after doses 1 and 2 were 3.9 and 32.2 AU/ml for HPV6, 5.3 and 45.6 AU/ml for HPV11, 20.8 and 187.9 IU/ml for HPV16; and 6.6 and 49.7 IU/ml for HPV18. No serious adverse events were reported.

Conclusion: All AI/AN children developed antibodies to all 4vHPV types after vaccination. GMCs rose after each dose, then decreased to a plateau over the subsequent two years. This cohort will continue to be followed to determine duration of antibody response.
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http://dx.doi.org/10.1016/j.vaccine.2020.08.005DOI Listing
September 2020

Gastric Cancer Among American Indian and Alaska Native Populations in the United States, 2005-2016.

Am J Gastroenterol 2020 12;115(12):1989-1997

Division of Cancer Prevention and Control, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.

Introduction: American Indian and Alaska Native (AI/AN) populations have higher gastric cancer rates than the general US population. This study provides a comprehensive overview of incidence rates among AI/AN persons during 2005-2016 compared with non-Hispanic whites (whites).

Methods: Population-based cancer registry data for 2005-2016 were linked with the Indian Health Service patient registration databases to address racial misclassification. Age-adjusted gastric cancer incidence rates were expressed per 100,000 per year. Incidence and trend analyses were restricted to purchased/referred care delivery area counties in 6 geographic regions, comparing gastric cancer incidence rates for AI/AN vs white populations in the United States.

Results: Gastric cancer rates were higher in the AI/AN compared with white populations in nearly every US region. Incidence rates for central/distal portions of the stomach were higher in AI/AN individuals compared with whites. Rates of later stage gastric cancer were higher in AI/AN populations overall and in every region except the Pacific Coast and East. Incidence rates decreased significantly over time in both populations. Declining rates in the AI/AN populations were driven by changes in the Pacific Coast and Northern Plains regions.

Discussion: AI/AN populations have a disproportionately high incidence of gastric cancer, especially in Alaska. High incidence in the central/distal portions of the stomach among AI/AN populations likely reflects a high prevalence of Helicobacter pylori infection in these populations. These data can be used to develop interventions to reduce risk factors and improve access to health services among AI/AN people at high risk for gastric cancer.
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http://dx.doi.org/10.14309/ajg.0000000000000748DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7710924PMC
December 2020

Presence of Antibodies Against Haemophilus influenzae Serotype a in Alaska Before and After the Emergence of Invasive Infections.

J Infect Dis 2021 Feb;223(2):326-332

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

Background: Haemophilus influenzae bacteria can cause asymptomatic carriage and invasive disease. Haemophilus influenzae serotype a (Hia) is an emerging cause of invasive disease in Alaska, with greatest burden occurring among rural Alaska Native (AN) children. The first case of invasive Hia (iHia) in Alaska was reported in 2002; however, it is unclear how long the pathogen has been in Alaska.

Methods: We quantified immunoglobulin G antibodies against Hia (anti-Hia) in 839 banked serum samples from Alaska residents, comparing antibody concentrations in samples drawn in the decades before (1980s and 1990s) and after (2000s) the emergence of iHia. We also assessed serum antibody concentration by age group, region of residence, and race.

Results: The anti-Hia was >0.1 µg/mL in 88.1% (348 of 395) and 91.0% (404 of 444) of samples from the decades prior and after the emergence of Hia, respectively (P = .17). No significant differences in antibody levels were detected between people from rural and urban regions (1.55 vs 2.08 µg/mL, P = .91 for age ≥5) or between AN and non-AN people (2.50 vs 2.60 µg/mL, P = .26).

Conclusions: Our results are consistent with widespread Hia exposure in Alaska predating the first iHia case. No difference in Hia antibody prevalence was detected between populations with differing levels of invasive disease.
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http://dx.doi.org/10.1093/infdis/jiaa369DOI Listing
February 2021

Epidemiology of Invasive Haemophilus influenzae Serotype a Disease-United States, 2008-2017.

Clin Infect Dis 2020 Jun 26. Epub 2020 Jun 26.

Arctic Investigations Program, CDC, Anchorage, AK, USA.

Background: Haemophilus influenzae serotype a (Hia) can cause invasive disease similar to serotype b; no Hia vaccine is available. We describe the epidemiology of invasive Hia disease in the United States overall and specifically in Alaska during 2008-2017.

Methods: Active population- and laboratory-based surveillance for invasive Hia disease was conducted through Active Bacterial Core surveillance sites and from Alaska statewide invasive bacterial disease surveillance. Sterile-site isolates were serotyped via slide agglutination or real-time polymerase chain reaction. Incidences in cases per 100,000 were calculated.

Results: From 2008-2017, an estimated average of 306 invasive Hia disease cases occurred annually in the United States (estimated annual incidence: 0.10); incidence increased by an average of 11.1% annually. Overall, 42.7% of cases were in children aged <5 years (incidence: 0.64), with highest incidence among children aged <1 year (1.60). Case fatality was 7.8% overall and was highest among adults aged ≥65 years (15.1%). Among children aged <5 years, incidence was 17 times higher among American Indians and Alaska Native (AI/AN) children (8.29) than among children of all other races combined (0.49). In Alaska, incidences among all ages (0.68) and among children aged <1 year (24.73) were nearly 6 and 14 times higher, respectively, than corresponding U.S. incidences. Case fatality in Alaska was 10.2%, and the vast majority (93.9%) of cases occurred among AI/AN.

Conclusions: Incidence of invasive Hia disease has increased since 2008, with the highest burden among AI/AN children. These data can inform prevention strategies, including Hia vaccine development.
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http://dx.doi.org/10.1093/cid/ciaa875DOI Listing
June 2020

Haemophilus influenzae serotype a (Hia) carriage in a small Alaska community after a cluster of invasive Hia disease, 2018.

Clin Infect Dis 2020 Jun 12. Epub 2020 Jun 12.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA.

Background: Between May and July 2018, four invasive Haemophilus influenzae serotype a (iHia) infections occurred in a remote Alaska community. We performed a public health response to prevent further illness and understand Hia carriage in the community.

Methods: We collected oropharyngeal (OP) samples community-wide from untreated individuals to evaluate baseline carriage. Risk factor data was collected by interview. To prevent additional illness, we offered prophylactic rifampin to individuals in contact with iHia patients (contacts) and to all children aged <10 years. OP samples were collected again eight weeks post-rifampin distribution. Samples were tested using real-time PCR and culture.

Results: At baseline, Hia was carried by 4/27 (14.8%) contacts and 7/364 (1.9%) non-contacts (p<0.01). Contacts aged <10 years were more likely to carry Hia at any timepoint (11/18, 61%) than contacts aged ≥10 years (3/34, 8.8%) or non-contacts aged <10 years (2/139, 1.4%) and ≥10 years (6/276, 2.2%)(p<0.001 for all). Hia carriers were clustered in nine households (7% of total households). At the household level, carriage was associated with households with ≥1 contact (PR=5.6, CI:1.3-21.6), crowding (PR=7.7, CI:1.1-199.5) and ≥3 tobacco users (PR=5.0, CI:1.2-19.6). Sixty-six percent (40/61) of contacts and 90% (111/124) of non-contacts aged <10 years received rifampin. Elevated carriage prevalence persisted in contacts when retested eight weeks after rifampin distribution (contacts 6/25 (24%), non-contacts 2/114 (1.8%), p<0.001).

Conclusions: Hia carriage prevalence was significantly higher among people who had contact with iHia patients than the general community. Rifampin prophylaxis did not result in a reduction of Hia carriage prevalence in this community.
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http://dx.doi.org/10.1093/cid/ciaa750DOI Listing
June 2020

Increasing non-susceptibility to antibiotics within carried pneumococcal serotypes - Alaska, 2008-2015.

Vaccine 2020 06 12;38(27):4273-4280. Epub 2020 May 12.

Centers for Disease Control and Prevention, Arctic Investigations Program, 4055 Tudor Center Drive, Anchorage, Alaska 99508, USA.

Background: In Alaska, while introduction of 13-valent pneumococcal conjugate vaccine led to declines in invasive pneumococcal disease, carriage prevalence remained stable because of replacement with non-vaccine serotypes. We assessed antibiotic non-susceptibility of carried pneumococci during serotype redistribution, determined the contributions of within-serotype shifts, and assessed factors that could explain changes in non-susceptibility.

Methods: Each year from 2008 to 2015, at multiple sites in Alaska, we collected nasopharyngeal swabs and completed surveys for a convenience sample of participants. Pneumococcal serotyping and antimicrobial susceptibility testing for penicillin and erythromycin were performed. We described changes in non-susceptibility of isolates from 2008-2011 to 2012-2015, and assessed the contributions of serotype redistribution and within-serotype changes in non-susceptibility by comparing observed data to modeled data removing either factor. We used weighted logistic regression to assess whether reported risk factors could explain changes over time in non-susceptibility within serotypes.

Results: From 2008-2011 to 2012-2015, the overall proportion of isolates non-susceptible to penicillin or erythromycin increased by 3%, from 23% (n = 1,183) to 26% (n = 1,589; P < 0.05). However, a decrease of 3% would be expected if serotype redistribution occurred without within-serotype changes in non-susceptibility. Standardization by either factor produced hypothetical data significantly different to observed data. Within serotypes, the average annual increase in odds of non-susceptibility to penicillin or erythromycin was 1.08 (95% CI 1.05-1.11). Recent antibiotic exposure, urban residence and increased household size of participants predicted isolate non-susceptibility but did not explain the increase over time.

Discussion: An overall increase in non-susceptibility of carried pneumococcal isolates to penicillin or erythromycin resulted from increases in non-susceptibility within serotypes, which outweighed a protective effect of serotype redistribution. Characterization of emerging resistant clones within carried non-vaccine serotypes, including risk factors for colonization and disease, would support disease prevention efforts and inform vaccine strategies.
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http://dx.doi.org/10.1016/j.vaccine.2020.04.048DOI Listing
June 2020

Presence of genes and characterization of s, i and m regions in isolated from Alaskans and their association with clinical pathologies.

J Med Microbiol 2020 Feb 3;69(2):218-227. Epub 2020 Feb 3.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA.

Gastric cancer is a health disparity in the Alaska Native people. The incidence of infection, a risk factor for non-cardia gastric adenocarcinoma, is also high. Gastric cancer is partially associated with the virulence of the infecting strain. To genotype the s, m and i and pathogenicity island () genes in from Alaskans and investigate associations with gastropathy. We enrolled patients with gastritis, peptic ulcer disease (PUD) and intestinal metaplasia (IM) in 1998-2005 and patients with gastric cancer in 2011-2013. Gastric biopsies were collected and cultured and PCR was performed to detect the presence of the right and left ends of the , the , , and genes and to genotype the s, m and i regions. We recruited 263 people; 22 (8 %) had no/mild gastritis, 121 (46 %) had moderate gastritis, 40 (15%) had severe gastritis, 38 (14 %) had PUD, 30 (11 %) had IM and 12 (5 %) had gastric cancer. isolates from 150 (57%) people had an intact ; those were associated with a more severe gastropathy (≤0.02 for all comparisons). isolates from 77 % of people had either the s1/i1/m1 (40 %; 94/234) or s2/i2/m2 (37 %; 86/234) genotype. s1/i1/m1 was associated with a more severe gastropathy (≤0.03 for all comparisons). In this population with high rates of gastric cancer, we found that just over half of the contained an intact and 40 % had the s1/i1/m1 genotype. Infection with these strains was associated with a more severe gastropathy.
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http://dx.doi.org/10.1099/jmm.0.001123DOI Listing
February 2020

Lack of in-home piped water and reported consumption of sugar-sweetened beverages among adults in rural Alaska.

Public Health Nutr 2020 04 24;23(5):861-868. Epub 2019 Sep 24.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

Objective: To assess whether a community water service is associated with the frequency of sugar-sweetened beverages (SSB) consumption, obesity, or perceived health status in rural Alaska.

Design: We examined the cross-sectional associations between community water access and frequency of SSB consumption, body mass index categories, and perceived health status using data from the 2013 and 2015 Alaska Behavioral Risk Factor Surveillance System (BRFSS). Participants were categorized by zip code to 'in-home piped water service' or 'no in-home piped water service' based on water utility data. We evaluated the univariable and multivariable (adjusting for age, household income and education) associations between water service and outcomes using log-linear survey-weighted generalized linear models.

Setting: Rural Alaska, USA.

Subjects: Eight hundred and eighty-seven adults, aged 25 years and older.

Results: In unadjusted models, participants without in-home water reported consuming SSB more often than participants with in-home water (1·46, 95 % CI: 1·06, 2·00). After adjustment for potential confounders, the effect decreased but remained borderline significant (1·29, 95 % CI: 1·00, 1·67). Obesity was not significantly associated with water service but self-reported poor health was higher in those communities without in-home water (1·63, 95 % CI: 1·05, 2·54).

Conclusions: Not having access to in-home piped water could affect behaviours surrounding SSB consumption and general perception of health in rural Alaska.
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http://dx.doi.org/10.1017/S1368980019002477DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7082197PMC
April 2020

Risk for Invasive Streptococcal Infections among Adults Experiencing Homelessness, Anchorage, Alaska, USA, 2002-2015.

Emerg Infect Dis 2019 10;25(10)

The risk for invasive streptococcal infection has not been clearly quantified among persons experiencing homelessness (PEH). We compared the incidence of detected cases of invasive group A Streptococcus infection, group B Streptococcus infection, and Streptococcus pneumoniae (pneumococcal) infection among PEH with that among the general population in Anchorage, Alaska, USA, during 2002-2015. We used data from the Centers for Disease Control and Prevention's Arctic Investigations Program surveillance system, the US Census, and the Anchorage Point-in-Time count (a yearly census of PEH). We detected a disproportionately high incidence of invasive streptococcal disease in Anchorage among PEH. Compared with the general population, PEH were 53.3 times as likely to have invasive group A Streptococcus infection, 6.9 times as likely to have invasive group B Streptococcus infection, and 36.3 times as likely to have invasive pneumococcal infection. Infection control in shelters, pneumococcal vaccination, and infection monitoring could help protect the health of this vulnerable group.
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http://dx.doi.org/10.3201/eid2510.181408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6759239PMC
October 2019

Risk-Based Prenatal Hepatitis C Testing Practices and Results, Alaska 2013-2016.

Can J Gastroenterol Hepatol 2019 2;2019:8654741. Epub 2019 Jun 2.

Alaska Native Tribal Health Consortium, Anchorage, AK, USA.

Hepatitis C virus (HCV) infection in pregnant women is of concern as it presents a health threat not only to the mother, but also to her infant. A retrospective analysis was performed to evaluate HCV testing and exposure in women who delivered infants between 2013 and 2016 at a referral hospital in Alaska. Multiple risk behaviors were evaluated, including drug dependency or abuse (drug abuse), tobacco use, alcohol dependency or abuse, and late presentation to prenatal care. Of the 2856 women who delivered between 2013 and 2016, 470 (16.5%) were tested for HCV during pregnancy and 1356 (47.5%) were tested at any time prior to delivery (including pregnancy); 62 (2.2%) were positive for HCV antibodies. Of the 162 women with a documented history of drug abuse, 95 (58.6%) were tested for HCV during pregnancy and 143 (88.3%) were tested at any time prior to delivery (including pregnancy); 30 (18.5%) were positive for HCV antibodies. Forty-nine women (34%) with a documented history of drug abuse who were not previously known to be HCV positive were not tested for HCV during their pregnancy. In conclusion, approximately 2% of pregnant women in the study population were known to have been exposed to HCV by the time of their delivery. One-third of women with documented drug abuse did not have an HCV test during pregnancy, revealing gaps in HCV testing of pregnant women. Further studies are needed to understand the full costs and benefits of risk-based screening versus universal screening in this and other populations.
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http://dx.doi.org/10.1155/2019/8654741DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582887PMC
July 2020

Hepatitis C in pregnant American Indian and Alaska native women; 2003-2015.

Int J Circumpolar Health 2019 12;78(1):1608139

a Arctic Investigations Program, Division of Preparedness and Emerging Infections , National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention , Anchorage , AK , USA.

Recent reports have found a rise in Hepatitis C virus (HCV) infection in reproductive age women in the USA. Surveillance data suggests one group that is at increased risk of HCV infection is the American Indian and Alaska Native population (AI/AN). Using the National Center for Health Statistics (NCHS) birth certificate and the Indian Health Services, Tribal, and Urban Indian (IHS) databases, we evaluated reported cases of HCV infection in pregnant women between 2003 and 2015. In the NCHS database, 38 regions consistently reported HCV infection. The percentage of mothers who were known to have HCV infection increased between 2011 and 2015 in both the AI/AN population (0.57% to 1.19%, p < 0.001) and the non-AI/AN population (0.21% to 0.36%, p < 0.001). The IHS database confirmed these results. Individuals with hepatitis B infection or intravenous drug use (IDU) had significantly higher odds of HCV infection (OR 16.4 and 17.6, respectively). In total, 62% of HCV-positive women did not have IDU recorded. This study demonstrates a significant increase in the proportion of pregnant women infected with HCV between 2003 and 2015. This increase was greater in AI/AN women than non-AI/AN women. This highlights the need for HCV screening and prevention in pregnant AI/AN women.
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http://dx.doi.org/10.1080/22423982.2019.1608139DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6493225PMC
December 2019

Human Seroprevalence to 11 Zoonotic Pathogens in the U.S. Arctic, Alaska.

Vector Borne Zoonotic Dis 2019 08 21;19(8):563-575. Epub 2019 Feb 21.

1Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

Due to their close relationship with the environment, Alaskans are at risk for zoonotic pathogen infection. One way to assess a population's disease burden is to determine the seroprevalence of pathogens of interest. The objective of this study was to determine the seroprevalence of 11 zoonotic pathogens in people living in Alaska. In a 2007 avian influenza exposure study, we recruited persons with varying wild bird exposures. Using sera from this study, we tested for antibodies to spp., spp., , , spp., spp., , , California serogroup bunyaviruses, and hepatitis E virus (HEV). Eight hundred eighty-seven persons had sera tested, including 454 subsistence bird hunters and family members, 160 sport bird hunters, 77 avian wildlife biologists, and 196 persons with no wild bird exposure. A subset ( = 481) of sera was tested for California serogroup bunyaviruses. We detected antibodies to 10/11 pathogens. Seropositivity to spp. (29%), California serotype bunyaviruses (27%), and (19%) was the most common; 63% (301/481) of sera had antibodies to at least one pathogen. Using a multivariable logistic regression model, spp. seropositivity was higher in females (35.7% vs. 25.0%;  = 0.01) and . seropositivity was higher in males (21.8% vs. 15.5%;  = 0.02). Alaska Native persons were more likely than non-Native persons to be seropositive to (11.7% vs. 3.8%;  = 0.005) and less likely to be seropositive to HEV (0.4% vs. 4.1%;  = 0.01). Seropositivity to spp., , HEV, and was associated with increasing age ( ≤ 0.01 for all) as was seropositivity to ≥1 pathogen ( < 0.0001). Seropositivity to zoonotic pathogens is common among Alaskans with the highest to spp., California serogroup bunyaviruses, and . This study provides a baseline for use in assessing seroprevalence changes over time.
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http://dx.doi.org/10.1089/vbz.2018.2390DOI Listing
August 2019

Response to Editorial.

Helicobacter 2019 04 3;24(2):e12558. Epub 2018 Dec 3.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging Zoonotic and Infectious Diseases, Centers for Disease Control and Prevention (CDC), Anchorage, Alaska.

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http://dx.doi.org/10.1111/hel.12558DOI Listing
April 2019

H. pylori-associated pathologic findings among Alaska native patients.

Int J Circumpolar Health 2018 12;77(1):1510715

a Arctic Investigations Program , DPEI/NCEZID, Centers for Disease Control and Prevention , Anchorage , AK , USA.

Helicobacter pylori infection is common among Alaska native (AN) people, however scant gastric histopathologic data is available for this population. This study aimed to characterise gastric histopathology and H. pylori infection among AN people. We enrolled AN adults undergoing upper endoscopy. Gastric biopsy samples were evaluated for pathologic changes, the presence of H. pylori, and the presence of cag pathogenicity island-positive bacteria. Of 432 persons; two persons were diagnosed with gastric adenocarcinoma, two with MALT lymphoma, 40 (10%) with ulcers, and 51 (12%) with intestinal metaplasia. Fifty-five per cent of H. pylori-positive persons had cag pathogenicity island positive bacteria. The gastric antrum had the highest prevalence of acute and chronic moderate-severe gastritis. H. pylori-positive persons were 16 and four times more likely to have moderate-severe acute gastritis and chronic gastritis (p < 0.01), respectively. An intact cag pathogenicity island positive was correlated with moderate-severe acute antral gastritis (53% vs. 31%, p = 0.0003). H. pylori-positive persons were more likely to have moderate-severe acute and chronic gastritis compared to H. pylori-negative persons. Gastritis and intestinal metaplasia were most frequently found in the gastric antrum. Intact cag pathogenicity island positive was correlated with acute antral gastritis and intestinal metaplasia.
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http://dx.doi.org/10.1080/22423982.2018.1510715DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6116699PMC
December 2018

Risk Factors for Group A Streptococcus Colonization During an Outbreak Among People Experiencing Homelessness in Anchorage, Alaska, 2017.

Clin Infect Dis 2018 11;67(11):1784-1787

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Zoonotic and Emerging Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

We identified risk factors for any emm type group A streptococcal (GAS) colonization while investigating an invasive emm26.3 GAS outbreak among people experiencing homelessness in Alaska. Risk factors included upper extremity skin breakdown, sleeping outdoors, sharing blankets, and infrequent tooth brushing. Our results may help guide control efforts in future outbreaks.
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http://dx.doi.org/10.1093/cid/ciy429DOI Listing
November 2018

Prevalence of Helicobacter pylori among Alaskans: Factors associated with infection and comparison of urea breath test and anti-Helicobacter pylori IgG antibodies.

Helicobacter 2018 Jun 14;23(3):e12482. Epub 2018 Mar 14.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA.

Background: Helicobacter pylori is one of the most common human infections in the world, and studies in Alaska Native people, as well as other Indigenous peoples, have shown a high prevalence of this gastric infection. This study was undertaken to determine the prevalence of H. pylori infection by urea breath test (UBT) and anti- H. pylori IgG among Alaskans living in four regions of the state and to identify factors associated with infection.

Methods: A convenience sample of persons > 6 months old living in five rural and one urban Alaskan community were recruited from 1996 to 1997. Participants were asked about factors possibly associated with infection. Sera were collected and tested for anti- H. pylori IgG antibodies; a UBT was administered to participants > 5 years old.

Results: We recruited 710 people of whom 571 (80%) were Alaska Native and 467 (66%) were from rural communities. Rural residents were more likely to be Alaska Native compared with urban residents (P < .001). Of the 710 people, 699 (98%) had a serum sample analyzed, and 634 (97%) persons > 5 years old had a UBT performed. H. pylori prevalence was 69% by UBT and 68% by anti- H. pylori IgG. Among those with a result for both tests, there was 94% concordance. Factors associated with H. pylori positivity were Alaska Native racial status, age ≥ 20 years, rural region of residence, living in a crowded home, and drinking water that was not piped or delivered.

Conclusions: Helicobacter pylori prevalence is high in Alaska, especially in Alaska Native persons and rural residents. Concordance between UBT and serology was also high in this group. Two socioeconomic factors, crowding and drinking water that was not piped or delivered, were found to be associated with H. pylori positivity.
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http://dx.doi.org/10.1111/hel.12482DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6640139PMC
June 2018

Re-emergence of pneumococcal colonization by vaccine serotype 19F in persons aged ≥5 years after 13-valent pneumococcal conjugate vaccine introduction-Alaska, 2008-2013.

Vaccine 2018 01 24;36(5):691-697. Epub 2017 Dec 24.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infections, Centers for Disease Control and Prevention, Anchorage, AK, USA.

Background: The pneumococcal conjugate vaccine (PCV) was introduced in 2001. Widespread PCV use nearly eradicated pneumococcal colonization by vaccine serotypes. Since 2008, however, colonization by PCV-serotype 19F has increased in Alaska residents. We describe the epidemiology of re-emerging serotype 19F colonization.

Methods: We conducted annual cross-sectional colonization surveys from 2008 to 2013. We recruited children aged <5 years at 2 urban clinics and participants of all ages from Region-A (2 villages), Region-B (4 villages), and Region-C (2 villages). We interviewed participants and reviewed their medical records to obtain demographic information and determine PCV status. We obtained nasopharyngeal swab specimens from participants to identify pneumococci and to determine the pneumococcal serotype, antimicrobial resistance, and multilocus sequence type. We used the Cochran-Armitage test to assess for significant trends in colonization across time periods.

Results: Among participants aged <5 years, pneumococcal serotype 19F colonization remained unchanged from 2008-2009 (0.7%) to 2012-2013 (0.5%; P-value [P] = .54). Serotype 19F colonization increased from 2008-2009 to 2012-2013 among participants aged 5-11 years (0.3% to 3.2%; P < .01), participants 12-17 years (0.0% to 2.0%; P < .01), and participants aged ≥18 years (0.1% to 0.5%; P < .01). During 2012-2013, 85 (93%) of 91 pneumococcal serotype 19F isolates were identified among participants from Region B; the majority of serotype 19F isolates belonged to an antimicrobial nonsusceptibility pattern corresponding to a novel multilocus sequence type 9074.

Conclusions: PCV continues to protect against serotype 19F colonization in vaccinated children aged <5 years. The direct PCV impact on serotype 19F colonization in persons aged 5-11 years and indirect impact in persons aged ≥12 years is waning, possibly because of a newly introduced genotype in Region-B.
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http://dx.doi.org/10.1016/j.vaccine.2017.12.035DOI Listing
January 2018

Invasive Haemophilus influenzae Serotype a Infection in Children: Clinical Description of an Emerging Pathogen-Alaska, 2002-2014.

Pediatr Infect Dis J 2018 04;37(4):298-303

Background: Invasive infections from Haemophilus influenzae serotype a (Hia) have been reported with increasing frequency, especially among indigenous populations. However, there are limited population-based studies of clinical severity. We studied invasive Hia infections in Alaska to determine clinical characteristics, mortality and sequelae.

Methods: We defined an invasive Hia infection as the first detection of Hia from a usually sterile site in a child <10 years of age from Alaska. We identified cases using the Alaska Invasive Bacterial Diseases Surveillance System and reviewed medical charts up to 2 years after reported illness.

Results: We identified invasive Hia infections in 36 children, 28 (78%) <1 year old, 34 (94%) living in an Alaskan village and 25 (69%) without documented underlying illness. Overlapping clinical presentations included meningitis in 15 children (42%); bacteremia and pneumonia in 10 children (28%); and bone, joint or soft tissue infections in 10 children (22%). In 4 other children, no source of invasive infection was identified. Intensive care was provided for 11 children (31%); 12 children (33%) required surgical intervention. One year after infection, 4 children (11%) had died from Hia, and 5 children (14%) had ongoing neurologic sequelae.

Conclusions: Invasive Hia infections in Alaska occurred predominantly in Alaska Native infants in rural communities. Although one-third of children had preexisting conditions, most cases occurred without known comorbidity. Clinical syndromes were frequently severe. One year after infection, 1 in 4 children had either died or had neurologic sequelae. An effective vaccine would prevent significant morbidity and mortality in affected populations.
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http://dx.doi.org/10.1097/INF.0000000000001764DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6362456PMC
April 2018

Observed Pneumococcal Carriage Among Alaska Native Children Who Received Reduced-Dose Schedules of 13-Valent Pneumococcal Conjugate Vaccine Between 2010 and 2012.

Clin Infect Dis 2018 04;66(9):1478-1479

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

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http://dx.doi.org/10.1093/cid/cix1020DOI Listing
April 2018

Outbreak of Invasive Infections From Subtype emm26.3 Group A Streptococcus Among Homeless Adults-Anchorage, Alaska, 2016-2017.

Clin Infect Dis 2018 03;66(7):1068-1074

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

Background: In 2016, we detected an outbreak of group A Streptococcus (GAS) invasive infections among the estimated 1000 persons experiencing homelessness (PEH) in Anchorage, Alaska. We characterized the outbreak and implemented a mass antibiotic intervention at homeless service facilities.

Methods: We identified cases through the Alaska GAS laboratory-based surveillance system. We conducted emm typing, antimicrobial susceptibility testing, and whole-genome sequencing on all invasive isolates and compared medical record data of patients infected with emm26.3 and other emm types. In February 2017, we offered PEH at 6 facilities in Anchorage a single dose of 1 g of azithromycin. We collected oropharyngeal and nonintact skin swabs on a subset of participants concurrent with the intervention and 4 weeks afterward.

Results: From July 2016 through April 2017, we detected 42 invasive emm26.3 cases in Anchorage, 35 of which were in PEH. The emm26.3 isolates differed on average by only 2 single-nucleotide polymorphisms. Compared to other emm types, infection with emm26.3 was associated with cellulitis (odds ratio [OR], 2.5; P = .04) and necrotizing fasciitis (OR, 4.4; P = .02). We dispensed antibiotics to 391 PEH. Colonization with emm26.3 decreased from 4% of 277 at baseline to 1% of 287 at follow-up (P = .05). Invasive GAS incidence decreased from 1.5 cases per 1000 PEH/week in the 6 weeks prior to the intervention to 0.2 cases per 1000 PEH/week in the 6 weeks after (P = .01).

Conclusions: In an invasive GAS outbreak in PEH in Anchorage, mass antibiotic administration was temporally associated with reduced invasive disease cases and colonization prevalence.
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http://dx.doi.org/10.1093/cid/cix921DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5862750PMC
March 2018

Population structure of invasive Streptococcus pneumoniae isolates among Alaskan children in the conjugate vaccine era, 2001 to 2013.

Diagn Microbiol Infect Dis 2016 Oct 7;86(2):224-30. Epub 2016 Jul 7.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infections Diseases, Centers for Disease Control and Prevention, 4055 Tudor Centre, Dr., Anchorage, AK, 99508, USA.

Here we describe the relationships between serotypes, genotypes, and antimicrobial susceptibility among isolates causing invasive pneumococcal disease in Alaskan children during the pneumococcal conjugate vaccine (PCV) era. From 2001 to 2013 we received 271 isolates representing 33 serotypes. The most common serotypes were 19A (29.5%, n= 80), 7F (12.5%, n= 34), 15B/C (6.3%, n= 17), and 22F (4.8%, n= 13). Multilocus sequence typing identified 11 clonal complexes (CC) and 45 singletons. Five CCs accounted for 52% (141/271) of the total: CC199 (21% [n= 57], serotypes 19A, 15B/C), CC191 (12.2% [n= 33], serotype 7F), CC172 (10.3% [n= 28], serotypes 19A, 23A, 23B), CC433 (4.4% [n= 12], serotype 22F), and CC100 (4.4% [n= 12], serotype 33F). The proportion of isolates nonsusceptible to erythromycin and tetracycline increased after 13-valent PCV use (14% [n= 30] versus 29% [n= 14]; P= 0.010) and (4% [n= 9] versus 22% [n= 11]; P< 0.001), respectively. The genetic diversity also increased after 13-valent PCV use (Simpson's diversity index =0.95 versus 0.91; P= 0.022).
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http://dx.doi.org/10.1016/j.diagmicrobio.2016.07.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5649341PMC
October 2016

The changing epidemiology and aetiology of hepatocellular carcinoma from 1969 through 2013 in Alaska Native people.

Liver Int 2016 12 16;36(12):1829-1835. Epub 2016 Jun 16.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging, Zoonotic and Infectious Diseases, Centers for Disease Control and Prevention (CDC), Anchorage, AK, USA.

Background & Aims: Alaska Native people have an increased rate of hepatocellular carcinoma compared to the United States population. Viral hepatitis is a risk factor for malignancy and the leading cause of hepatocellular carcinoma in Alaska. With the introduction of hepatitis B immunization in 1982, as well as the emergence of hepatitis C virus in this population, the epidemiology and aetiology of hepatocellular carcinoma in Alaska have changed.

Methods: Using the Alaska Native Tumor Registry, all cases of viral and non-viral hepatocellular carcinoma occurring from 1969 through 2013 were identified and reviewed. Incidence rates per 100 000 population were calculated for hepatocellular carcinoma overall and by aetiological category.

Results: One hundred and fifty-two cases of hepatocellular carcinoma were identified in 148 Alaska Native persons. Overall tumour rate was 3.82 per 100 000 and did not change significantly over the study period. Hepatitis B-associated cases decreased significantly over the study period (P = 0.048) and were eliminated in persons under the age of 20. Hepatitis C-associated cases increased significantly (P < 0.001). Undetermined hepatocellular carcinoma rates also decreased (P = 0.034).

Conclusions: Overall hepatocellular carcinoma rates in Alaska Native people remained stable over the study period, but the epidemiology and aetiology are changing. Two decades after routine hepatitis B immunization, the hepatocellular carcinoma age distribution has shifted to cases presenting later in life. This is consistent with an ageing hepatitis B-infected population with no new infected young persons' coming into the population, as well as the emergence of hepatitis C in adults.
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http://dx.doi.org/10.1111/liv.13173DOI Listing
December 2016

Cost-effectiveness analysis of hepatocellular carcinoma screening by combinations of ultrasound and alpha-fetoprotein among Alaska Native people, 1983-2012.

Int J Circumpolar Health 2016 18;75:31115. Epub 2016 May 18.

Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Disease, U.S. Centers for Disease Control and Prevention (CDC), Anchorage, AK, USA.

Background: The American Association for the Study of Liver Diseases (AASLD) recommends semi-annual hepatocellular carcinoma (HCC) screening using ultrasound (US) in persons with chronic hepatitis B (CHB) virus infection at high risk for HCC such as Asian males aged ≥40 years and Asian females aged ≥50 years.

Objective: To analyse the cost-effectiveness of 2 HCC screening methods in the Alaska Native (AN) health system: US-alone, or screening by alpha-fetoprotein (AFP) initially and switching to US for subsequent screenings if AFP >10 ng/mL (AFP→US).

Design: A spreadsheet-based model was developed for accounting the costs of 2 hypothetical HCC screening methods. We used epidemiologic data from a cohort of 839 AN persons with CHB who were offered HCC screening by AFP/US semi-annually during 1983-2012. We assumed that compared with AFP→US, US-alone identifies 33% more tumours at an early stage (defined as a single tumour ≤5 cm or ≤3 tumours ≤3 cm in diameter). Years of life gained (YLG) attributed to screening was estimated by comparing additional years of survival among persons with early- compared with late-stage tumours. Screening costs were calculated using Medicare reimbursement rates in 2012. Future screening costs and YLG were projected over a 30-year time horizon using a 3% discount rate.

Results: The total cost of screening for the cohort by AFP→US would have been approximately $357,000 ($36,000/early-stage tumour detected) compared to $814,000 ($59,000/early-stage tumour detected) by US-alone. The AFP→US method would have yielded an additional 27.8 YLG ($13,000/YLG) compared with 38.9 YLG ($21,000/YLG) for US-alone. Screening by US-alone would incur an additional $114,000 per extra early-tumour detected compared with AFP→US and $41,000 per extra YLG.

Conclusions: Although US-alone HCC screening might have yielded more YLG than AFP→US, the reduced costs of the AFP→US method could expand access to HCC screening in resource constrained settings.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4873562PMC
http://dx.doi.org/10.3402/ijch.v75.31115DOI Listing
January 2018

A Longitudinal Hepatitis B Vaccine Cohort Demonstrates Long-lasting Hepatitis B Virus (HBV) Cellular Immunity Despite Loss of Antibody Against HBV Surface Antigen.

J Infect Dis 2016 07 7;214(2):273-80. Epub 2016 Apr 7.

Liver Disease and Hepatitis Program, Alaska Native Tribal Health Consortium Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention (CDC).

Background: Long-lasting protection resulting from hepatitis B vaccine, despite loss of antibody against hepatitis B virus (HBV) surface antigen (anti-HBs), is undetermined.

Methods: We recruited persons from a cohort vaccinated with plasma-derived hepatitis B vaccine in 1981 who have been followed periodically since. We performed serological testing for anti-HBs and microRNA-155 and assessed HBV-specific T-cell responses by enzyme-linked immunospot and cytometric bead array. Study subgroups were defined 32 years after vaccination as having an anti-HBs level of either ≥10 mIU/mL (group 1; n = 13) or <10 mIU/mL (group 2; n = 31).

Results: All 44 participants, regardless of anti-HBs level, tested positive for tumor necrosis factor α, interleukin 10, or interleukin 6 production by HBV surface antigen-specific T cells. The frequency of natural killer T cells correlated with the level of anti-HBs (P = .008). The proportion of participants who demonstrated T-cell responses to HBV core antigen varied among the cytokines measured, suggesting some natural exposure to HBV in the study group. No participant had evidence of breakthrough HBV infection.

Conclusions: Evidence of long-lasting cellular immunity, regardless of anti-HBs level, suggests that protection afforded by primary immunization with plasma-derived hepatitis B vaccine during childhood and adulthood lasts at least 32 years.
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http://dx.doi.org/10.1093/infdis/jiw142DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4918827PMC
July 2016

Incidence of hepatocellular carcinoma according to hepatitis B virus genotype in Alaska Native people.

Liver Int 2016 10 6;36(10):1507-15. Epub 2016 Apr 6.

Arctic Investigations Program, Division of Preparedness & Emerging Infections, National Center for Emerging & Zoonotic Infectious Disease, Centers for Disease Control & Prevention, Anchorage, AK, USA.

Background & Aims: Most regions of the world have ≤3 co-circulating hepatitis B virus (HBV) genotypes, which limits direct comparisons of hepatocellular carcinoma (HCC) risk among HBV-infected persons by genotype. We evaluated HCC incidence by HBV genotype in a cohort of Alaska Native (AN) persons where five HBV genotypes (A, B, C, D, F) have been identified.

Methods: Our cohort comprised AN persons with chronic HBV infection identified during 1983-2012 who consented to participate in this study. Cohort persons were offered annual hepatitis B e antigen (HBeAg) testing and semi-annual HCC screening. We developed a logistic regression model to compare HCC risk by genotype, adjusting for age, sex, region and HBeAg status.

Results: Among the 1235 consenting study participants, 711 (57.6%) were male, 510 (41.3%) were HBeAg positive at cohort entry and 43 (3.5%) developed HCC. The HBV genotype was known for 1142 (92.5%) persons (13.5% A, 3.9% B, 6.7% C, 56.9% D, 19.0% F). The HCC incidence/1000 person-years of follow-up for genotypes A, B, C, D and F was 1.3, 0, 5.5, 0.4 and 4.2 respectively. Compared with persons with HBV genotype B/D infection, the HCC risk was higher for persons with genotypes A [adjusted odds ratio (aOR): 3.9, 95% confidence interval (CI): 1.14-13.74], C (aOR: 16.3, 95% CI: 5.20-51.11) and F (aOR: 13.9, 95% CI: 5.30-36.69).

Conclusion: HBV genotype is independently associated with HCC risk. AN persons with genotypes A, C and F are at higher risk compared with genotypes B or D.
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http://dx.doi.org/10.1111/liv.13129DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5021564PMC
October 2016