Impact of a Prenatal Vitamin D Supplementation Program on Vitamin D Deficiency, Rickets and Early Childhood Caries in an Alaska Native Population.

Background: Early childhood rickets increased in Alaska Native children after decreases in vitamin D-rich subsistence diet in childbearing-aged women. We evaluated the impact of routine prenatal vitamin D supplementation initiated in Alaska's Yukon Kuskokwim Delta in Fall 2016. Methods: We queried electronic health records of prenatal women with 25(OH) vitamin D testing during the period 2015−2019. We evaluated 25(OH)D concentrations, vitamin D3 supplement refills, and decayed, missing, and filled teeth (dmft) scores and rickets in offspring. Results: Mean 25(OH)D concentrations increased 36.5% from pre- to post-supplementation; the percentage with deficient 25(OH)D decreased by 66.4%. Women with ≥ 60 vitamin D3 refill days had higher late pregnancy 25(OH)D concentrations than those with no refill days (p < 0.0001). Women with late pregnancy insufficient 25(OH)D concentrations had offspring with higher dmft scores than those with sufficient 25(OH)D (RR 1.3, p < 0.0001). Three children were diagnosed with nutritional rickets during the period 2001−2021, and none after 2017. Conclusions: These findings suggest that prenatal vitamin D supplementation can improve childhood outcomes in high-risk populations with high rates of rickets.

HIV Transmission Through Premastication.

Premastication is a potential route of transmission of HIV from caregiver to child. We report the case of a 13-month-old Alaska Native child from rural Alaska who presented with failure to thrive, recurrent pneumonias, severe dental decay, and dysphagia. The mother was HIV-uninfected. Respiratory failure prompted transfer to a children's hospital outside of Alaska where the child received a diagnosis of HIV infection. A grandparent who had been acting as primary caregiver was discovered to be HIV-infected with detectable viral load resulting from intermittent nonadherence to her medication regimen. This grandparent reported feeding the child premasticated food. Sequencing of the hypervariable C2V5 region of the HIV envelope gene in both patients demonstrated less than 0.05% variation, consistent with transmission from grandparent to child. Health care providers should be aware that transmission of HIV can occur via premastication, educate parents and caregivers regarding this risk, and rigorously pursue HIV testing when indicated even in children with HIV-uninfected mothers.

Life-threatening viral disease in a novel form of autosomal recessive IFNAR2 deficiency in the Arctic.

Type I interferons (IFN-I) play a critical role in human antiviral immunity, as demonstrated by the exceptionally rare deleterious variants of IFNAR1 or IFNAR2. We investigated five children from Greenland, Canada, and Alaska presenting with viral diseases, including life-threatening COVID-19 or influenza, in addition to meningoencephalitis and/or hemophagocytic lymphohistiocytosis following live-attenuated viral vaccination. The affected individuals bore the same homozygous IFNAR2 c.157T>C, p.Ser53Pro missense variant. Although absent from reference databases, p.Ser53Pro occurred with a minor allele frequency of 0.034 in their Inuit ancestry. The serine to proline substitution prevented cell surface expression of IFNAR2 protein, small amounts of which persisted intracellularly in an aberrantly glycosylated state. Cells exclusively expressing the p.Ser53Pro variant lacked responses to recombinant IFN-I and displayed heightened vulnerability to multiple viruses in vitro-a phenotype rescued by wild-type IFNAR2 complementation. This novel form of autosomal recessive IFNAR2 deficiency reinforces the essential role of IFN-I in viral immunity. Further studies are warranted to assess the need for population screening.

Transplacental Respiratory Syncytial Virus and Influenza Virus Antibody Transfer in Alaska Native and Seattle Mother-Infant Pairs.

BACKGROUND: Alaska Native (AN) infants are at risk for severe disease due to respiratory syncytial virus (RSV) and influenza. Maternal immunization protects young infants through transplacental antibody transfer. RSV- and influenza-specific transplacental antibody transfer in mother-infant pairs has not previously been evaluated in the AN population. METHODS: Serum samples collected during pregnancy and at birth from AN mother-infant pairs in the Yukon-Kuskokwim Delta region (YKD) of Alaska (2000-2011; n = 75) and predominantly white pairs in Seattle, Washington (2014-2016; n = 57), were tested for RSV and influenza antibody using a microneutralization and hemagglutination inhibition assay, respectively, and compared between sites. RESULTS: Mean RSV antibody concentrations in pregnant women in YKD and Seattle were similar (log2 RSV antibody 10.6 vs 10.7, P = .86), but cord blood RSV antibody concentrations were significantly lower in infants born to mothers in YKD compared with Seattle (log2 RSV antibody 11.0 vs 12.2, P < .001). Maternal and cord blood influenza antibody concentrations were lower for women and infants in YKD compared with Seattle for all 4 influenza antigens tested (all P < .05). The mean cord to maternal RSV antibody transfer ratio was 1.15 (standard deviation [SD], 0.13) in mother-infant pairs in Seattle compared with 1.04 (SD, 0.08) in YKD. Mean cord blood to maternal antibody transfer ratios for influenza antigens ranged from 1.22 to 1.42 in Seattle and from 1.05 to 1.59 in YKD. CONCLUSIONS: Though the transplacental antibody transfer ratio was high (>1.0) for both groups, transfer ratios for RSV antibody were significantly lower in AN mother-infant pairs. Further studies are needed to elucidate the impact of lower transplacental antibody transfer on infant disease risk in rural Alaska.Alaska Native and continental US mother-infant pairs have high transplacental antibody transfer ratios (>1.0) for influenza and respiratory syncytial virus, but anti-respiratory syncytial virus antibody levels are significantly lower in Alaska Native pairs than in those from the continental US.

Healthy Pregnancies Project: Cluster Randomized Controlled Trial of a Community Intervention to Reduce Tobacco Use among Alaska Native Women.

Substantial gaps remain in the evidence base for prenatal tobacco use interventions among Indigenous women. Using a cluster randomized controlled trial (RCT), the Healthy Pregnancies Project evaluated a community-level intervention for Alaska Native (AN) women in rural western Alaska. Sixteen villages were randomly assigned to usual care (control, n = 8 villages) or usual care plus a community-level intervention delivered by local AN "Native Sisters" (n = 8 villages). Outcomes were tobacco use rate at delivery and at 2 and 6 months postpartum, with biochemical confirmation obtained at 6 months. The program had high reach, enrolling 73% of all eligible women screened. Of the 352 participants, 67% used tobacco at baseline. No significant differences emerged between study groups on follow-up in tobacco use rates. More intervention than control participants made a quit attempt at 2 months postpartum (70% vs. 51%, respectively, p = 0.012). Participants in both study groups reported the program helped to raise awareness of healthy pregnancies in the study villages. This trial supports the reach of a community-level intervention, but not its efficacy for reducing tobacco use during pregnancy or postpartum. Efforts to sustain early quit attempts appear warranted. The community involvement, and reported impact on raising awareness of the importance of healthy pregnancies, supports the value of the research program in this community.

Respiratory syncytial virus and influenza hospitalizations in Alaska native adults.

BACKGROUND: Alaska Native (AN) infants from Yukon Kuskokwim Delta (YKD) have the highest U.S. infant hospitalization rate for respiratory syncytial virus (RSV). RSV can cause significant morbidity and mortality in adult populations, although the RSV burden in AN adults is unknown. Here we investigate RSV, influenza, and human metapneumovirus (hMPV) in hospitalized rural AN adults. METHODS: YKD AN adults, hospitalized with acute respiratory illness between November 2016 and October 2018 were enrolled prospectively. Nasopharyngeal (NP) swabs were tested for RSV, influenza and hMPV using polymerase chain reaction. Hospitalization rates were calculated. RESULTS: Of 251 patients who had an NP swab, RSV was detected in 8 (3.2 %), influenza in 31 (12.4 %), and hMPV in no patients. Weighted annual rates of lower respiratory tract infection (LRTI), RSV and influenza hospitalization were 192.0 (95 % CI: 176.5-208.4), 9.1 (6.0-13.3), and 42.2 (35.1-50.2) per 10,000. The most common discharge diagnosis was pneumonia (57.0 %), followed by chronic obstructive pulmonary disease (51.4 %). Ninety-eight percent (246/251) had a medical co-morbidity and 49.8 % (125/251) lived in a house with a smoker. Overall, 6.4 % (16/251) required mechanical ventilation, and 3.6 % (9/251) died during hospitalization. Only 35.7 % (66/185) of patients admitted during influenza season had received the annual influenza vaccine. DISCUSSION: We examined adult LRTI, influenza, and RSV hospitalization rates in an AN population with high infant RSV hospitalization rates. While we confirmed a high rate of hospitalization from LRTIs and influenza, we did not find a high rate due to RSV or hMPV. Improving influenza vaccination rates, and addressing co-morbidities could reduce respiratory hospitalizations.

Association of Tobacco Use During Pregnancy, Perceived Stress, and Depression Among Alaska Native Women Participants in the Healthy Pregnancies Project.

INTRODUCTION: In general population samples, higher levels of stress and depression have been associated with increased prevalence of smoking in pregnancy. Little is known about the association of prenatal tobacco use, stress, and depression among American Indian or Alaska Native (AI/AN) women. METHODS: The Healthy Pregnancies Project is a cluster-randomized controlled trial, evaluating a community-level intervention compared with usual care, for reducing tobacco use during pregnancy and postpartum among AN women in 16 villages in western Alaska. This cross-sectional study analyzed baseline data from enrolled pregnant women. Baseline measures included the self-reported, 7-day, point-prevalence current use of any tobacco, Perceived Stress Scale (PSS), and the Center for Epidemiological Studies-Depression (CES-D). Generalized estimating equations (GEE) analyses adjusted for village, participant age, and gestational age. RESULTS: Participants (N = 352) were on average (SD) 25.8 (5.0) years of age and at 26.8 (9.8) weeks gestation. 66.5% were current tobacco users, of which 77% used Iqmik, a homemade form of smokeless tobacco. Compared with nonusers, tobacco users reported lower PSS score (p = .020) and less clinical levels of depression (CES-D ≥ 16) (18.1% vs. 9.3%, p = .21). Findings were not accounted for by nicotine dependence severity or self-reported tobacco use before pregnancy. CONCLUSIONS: In this sample of pregnant AN women, tobacco users report less stress and clinical levels of depression than nonusers. A potential challenge with tobacco treatment for pregnant AN women is to provide alternative ways of deescalating stress and affect management instead of using tobacco. IMPLICATIONS: This study contributes novel information on the association of tobacco use, perceived stress, and depression among Alaska Native women enrolled in a clinical trial to promote healthy pregnancies. Most prior studies addressing this topic were conducted among general population samples of pregnant women who smoked cigarettes. Little is known about these associations with prenatal smokeless tobacco, or among American Indian or Alaska Native women. The results are contrary to findings reported previously, because current tobacco use was associated with less stress and depression than nonuse. The study findings have implications for cessation treatment for this tobacco-use disparity group.

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

Background: 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. Methods: 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 Cryptosporidium spp., Echinococcus spp., Giardia intestinalis, Toxoplasma gondii, Trichinella spp., Brucella spp., Coxiella burnetii, Francisella tularensis, California serogroup bunyaviruses, and hepatitis E virus (HEV). Results: 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 (n = 481) of sera was tested for California serogroup bunyaviruses. We detected antibodies to 10/11 pathogens. Seropositivity to Cryptosporidium spp. (29%), California serotype bunyaviruses (27%), and G. intestinalis (19%) was the most common; 63% (301/481) of sera had antibodies to at least one pathogen. Using a multivariable logistic regression model, Cryptosporidium spp. seropositivity was higher in females (35.7% vs. 25.0%; p = 0.01) and G. intestinalis seropositivity was higher in males (21.8% vs. 15.5%; p = 0.02). Alaska Native persons were more likely than non-Native persons to be seropositive to C. burnetii (11.7% vs. 3.8%; p = 0.005) and less likely to be seropositive to HEV (0.4% vs. 4.1%; p = 0.01). Seropositivity to Cryptosporidium spp., C. burnetii, HEV, and Echinococcus granulosus was associated with increasing age (p ≤ 0.01 for all) as was seropositivity to ≥1 pathogen (p < 0.0001). Conclusion: Seropositivity to zoonotic pathogens is common among Alaskans with the highest to Cryptosporidium spp., California serogroup bunyaviruses, and G. intestinalis. This study provides a baseline for use in assessing seroprevalence changes over time.

The Healthy Pregnancies Project: Study protocol and baseline characteristics for a cluster-randomized controlled trial of a community intervention to reduce tobacco use among Alaska Native pregnant women.

BACKGROUND: Tobacco use prevalence is high among pregnant Alaska Native (AN) women but few interventions have been evaluated for this group. The Healthy Pregnancies Project aims to evaluate a multicomponent intervention for reducing tobacco use during pregnancy and the postpartum period among AN women. This report describes the study protocol and participant baseline characteristics. DESIGN: Cluster-randomized controlled trial with village as the unit of assignment. Sixteen villages in rural southwest Alaska were stratified on village size and randomized to a multicomponent intervention (n = 8 villages) or usual care (n = 8 villages). METHODS: Pregnant AN women from the study villages were enrolled. All participants receive the usual care provided to pregnant women in this region. Participants from intervention villages additionally receive individual phone counseling on healthy pregnancies plus a social marketing campaign targeting the entire community delivered by local AN "Native Sisters." Baseline measurements for all enrolled pregnant women have been completed. Follow-up assessments are ongoing at delivery, and at 2 and 6 months postpartum. The primary outcome is biochemically verified tobacco use status at 6 months postpartum. RESULTS: Recruitment was feasible with 73% of eligible women screened enrolled. The program reached more than half (56%) of AN pregnant women from the study villages during the recruitment period. Participants are N = 352 pregnant AN women, 188 enrolled from intervention villages and 164 from control villages. At baseline, participants' mean (SD) age was 25.8 (5.0) years, they were at 26.8 (9.8) weeks gestation, and 66.5% were current tobacco users. DISCUSSION: Processes and products from this project may have relevance to other Native American populations aiming to focus on healthy pregnancies in their communities.

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

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.

Declines in traditional marine food intake and vitamin D levels from the 1960s to present in young Alaska Native women.

OBJECTIVE: To measure the trends in traditional marine food intake and serum vitamin D levels in Alaska Native women of childbearing age (20-29 years old) from the 1960s to the present. DESIGN: We measured a biomarker of traditional food intake, the δ15N value, and vitamin D level, as 25-hydroxycholecalciferol (25(OH)D3) concentration, in 100 serum samples from 20-29-year-old women archived in the Alaska Area Specimen Bank, selecting twenty-five per decade from the 1960s to the 1990s. We compared these with measurements of red-blood-cell δ15N values and serum 25(OH)D3 concentrations from 20-29-year-old women from the same region collected during the 2000s and 2010s in a Center for Alaska Native Health Research study. SETTING: The Yukon Kuskokwim Delta region of south-west Alaska. SUBJECTS: Alaska Native women (n 319) aged 20-29 years at the time of specimen collection. RESULTS: Intake of traditional marine foods, as measured by serum δ15N values, decreased significantly each decade from the 1960s through the 1990s, then remained constant from the 1990s through the present (F 5,306=77·4, P<0·0001). Serum vitamin D concentrations also decreased from the 1960s to the present (F 4,162=26·1, P<0·0001). CONCLUSIONS: Consumption of traditional marine foods by young Alaska Native women dropped significantly between the 1960s and the 1990s and was associated with a significant decline in serum vitamin D concentrations. Studies are needed to evaluate the promotion of traditional marine foods and routine vitamin D supplementation during pregnancy for this population.

A survey of knowledge, attitudes, and practices towards skin and soft tissue infections in rural Alaska.

BACKGROUND: Community-acquired methicillin-resistant Staphylococcus aureus and methicillin-sensitive S. aureus infections are common to south-western Alaska and have been associated with traditional steambaths. More than a decade ago, recommendations were made to affected communities that included preventive skin care, cleaning methods for steambath surfaces, and the use of protective barriers while in steambaths to reduce the risk of S. aureus infection. OBJECTIVE: A review of community medical data suggested that the number of skin infection clinical encounters has increased steadily over the last 3 years and we designed a public health investigation to seek root causes. STUDY DESIGN: Using a mixed methods approach with in-person surveys, a convenience sample (n=492) from 3 rural communities assessed the range of knowledge, attitudes and practices concerning skin infections, skin infection education messaging, prevention activities and home self-care of skin infections. RESULTS: We described barriers to implementing previous recommendations and evaluated the acceptability of potential interventions. Prior public health messages appear to have been effective in reaching community members and appear to have been understood and accepted. We found no major misconceptions regarding what a boil was or how someone got one. Overall, respondents seemed concerned about boils as a health problem and reported that they were motivated to prevent boils. We identified current practices used to avoid skin infections, such as the disinfection of steambaths. We also identified barriers to engaging in protective behaviours, such as lack of access to laundry facilities. CONCLUSIONS: These findings can be used to help guide public health strategic planning and identify appropriate evidence-based interventions tailored to the specific needs of the region.

Exploring pathways to trust: a tribal perspective on data sharing.

The data-sharing policies of the National Institutes of Health aim to maximize public benefit derived from genetic studies by increasing research efficiency and use of a pooled data resource for future studies. Although broad access to data may lead to benefits for populations underrepresented in genetic studies, such as indigenous groups, tribes have ownership interest in their data. The Northwest-Alaska Pharmacogenetic Research Network, a partnership involving tribal organizations and universities conducting basic and translational pharmacogenetic research, convened a meeting to discuss the collection, management, and secondary use of research data, and of the processes surrounding access to data stored in federal repositories. This article reports the tribal perspectives that emerged from the dialogue and discusses the implications of tribal government sovereign status on research agreements and data-sharing negotiations. There is strong tribal support for efficient research processes that expedite the benefits from collaborative research, but there is also a need for data-sharing procedures that take into account tribal sovereignty and appropriate oversight of research--such as tribally based research review processes and review of draft manuscripts. We also note specific ways in which accountability could be encouraged by the National Institutes of Health as part of the research process.

Community and federal collaboration to assess pregnancy outcomes in Alaska Native women, 1997-2005.

The objectives are to report the estimated prevalence of pregnancy complications and adverse pregnancy outcomes in a defined population of Alaska Native women and also examine factors contributing to an intensive and successful collaboration between a tribal health center and the Centers for Disease Control and Prevention. Investigators abstracted medical record data from a random sample of singleton deliveries to residents of the study region occurring between 1997 and 2005. We used descriptive statistics to estimate the prevalence and 95% confidence intervals of selected pregnancy complications and adverse pregnancy outcomes. Records were examined for 505 pregnancies ending in a singleton delivery to 469 women. Pregnancy complication rates were 5.9% (95% CI 4.0, 8.4) for gestational diabetes mellitus, 6.1% (95% CI 4.2, 8.6%) for maternal chronic hypertension and 11.5% (95% CI 8.8, 14.6) for pregnancy associated hypertension, and 22.9% (95% CI 19.2-26.5 %) for anemia. The cesarean section rate was 5.5% (95% CI 3.5, 7.5) and 3.8% (95% CI 2.3, 5.8) of newborns weighed >4,500 g. Few previous studies reported pregnancy outcomes among Alaska Native women in a specific geographic region of Alaska and regarding the health needs in this population. We highlight components of our collaboration that contributed to the success of the study. Studies focusing on special populations such as Alaska Native women are feasible and can provide important information on health indicators at the local level.

Haemophilus influenzae serotype a invasive disease, Alaska, USA, 1983-2011.

Before introduction of Haemophilus influenzae type b (Hib) vaccines, rates of Hib disease in Alaska's indigenous people were among the highest in the world. Vaccination reduced rates dramatically; however, invasive H. influenzae type a (Hia) disease has emerged. Cases of invasive disease were identified through Alaska statewide surveillance during 1983-2011. Of 866 isolates analyzed for serotype, 32 (4%) were Hia. No Hia disease was identified before 2002; 32 cases occurred during 2002-2011 (p<0.001). Median age of case-patients was 0.7 years; 3 infants died. Incidence of Hia infection (2002-2011) among children <5 years was 5.4/100,000; 27 cases occurred in Alaska Native children (18/100,000) versus 2 cases in non-Native children (0.5/100,000) (risk ratio = 36, p<0.001). From 12/2009 to 12/2011, 15 cases of Hia disease occurred in southwestern Alaska (in children <5 years, rate = 204/100,000). Since introduction of the Hib conjugate vaccine, Hia infection has become a major invasive bacterial disease in Alaska Native children.

The 13-valent pneumococcal conjugate vaccine for invasive pneumococcal disease in Alaska native children: results of a clinical trial.

BACKGROUND: During 1996 to 2000, Alaska Native children aged <5 years from Yukon Kuskokwim Delta (YKD) had invasive pneumococcal disease (IPD) rates 10-fold higher than non-Alaska Native children (547/100,000/yr versus 56/100,000/yr). After 7-valent pneumococcal conjugate vaccine (PCV7) introduction, IPD rates decreased to 148 per 100,000 during 2001 to 2004, increasing to 426 per 100,000 during 2005 to 2007 due to non-vaccine serotype disease. In 2009, we evaluated safety, immunogenicity and impact of 13-valent PCV (PCV13) in YKD children. METHODS: In a prelicensure open-label clinical trial, eligible YKD children aged <5 years were offered PCV13 as appropriate for age and prior PCV7 history. PCV13 impact was assessed using existing Alaska-wide IPD surveillance. Serotype-specific anti-pneumococcal IgG levels were measured postinfant series and posttoddler dose in a subset of subjects. Adverse events and serious adverse events were collected in all; local reactions and systemic events were collected in toddlers. All YKD children were offered licensed PCV13 when it became available. RESULTS: Three hundred seventy-two subjects received PCV13 during the clinical trial and 3342 postlicensure (April 2010 to August 2011). Adverse events were typically mild, or generally consistent with common childhood illnesses. IgG levels following PCV13 were similar to other populations. In YKD children aged <5 years, 52 IPD cases (31 PCV13-serotype) occurred during 2005 to 2008 (399.0/100,000/yr) versus 9 (7 PCV13-serotype) during January 2009 to August 2011 (106.7/100,000/yr; P < 0.001). No PCV13-serotype cases occurred among PCV13 recipients (3680 person follow-up years). CONCLUSIONS: PCV13-serotype IPD incidence declined significantly after PCV13 introduction. Although non-PCV13-serotype IPD also declined significantly, absence of PCV13-serotype IPD in children who received PCV13 suggests a protective vaccine effect.

Community-based participatory research in a large cohort study of chronic diseases among Alaska native adults.

BACKGROUND: In 2001, the National Cancer Institute (NCI) funded a project to develop methods to recruit American Indian and Alaska Native (AI/AN) adults for a prospective cohort study of chronic disease risk and protective factors. OBJECTIVE: We describe how the use of community-based participatory research (CBPR) principles led to more effective study design and implementation in a study in Alaska. METHODS: CBPR elements included collaboration between researchers and tribes at all stages of the project, capacity building through training AI/AN staff in research methods, and knowledge dissemination through presentations, newsletters, and individual and community health feedback based on results of the study. RESULTS: Between March 2004 and August 2006, 3,821 AI/ AN adults from 26 Alaskan communities enrolled in the study. Retention in the study is high, with over 88% of participants successfully completing a 2-year follow-up questionnaire. CONCLUSION: CBPR methods have facilitated effective development of study methods, recruitment and retention. Efforts are on-going to continue work with this unique AI/AN research participant community.

Methicillin-Resistant Staphylococcus aureus carriage and risk factors for skin infections, Southwestern Alaska, USA.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are common in southwestern Alaska. Outbreak strains have been shown to carry the genes for Panton-Valentine leukocidin (PVL). To determine if carriage of PVL-positive CA-MRSA increased the risk for subsequent soft tissue infection, we conducted a retrospective cohort study by reviewing the medical records of 316 persons for 3.6 years after their participation in a MRSA nasal colonization survey. Demographic, nasal carriage, and antimicrobial drug use data were analyzed for association with skin infection risk. Skin infections were more likely to develop in MRSA carriers than in methicillin-susceptible S. aureus carriers or noncarriers of S. aureus during the first follow-up year, but not in subsequent years. Repeated skin infections were more common among MRSA carriers. In an area where PVL-containing MRSA is prevalent, skin infection risk was increased among MRSA nasal carriers compared with methicillin-susceptible S. aureus carriers and noncarriers, but risk differential diminished over time.

Invasive pneumococcal disease in Alaskan children: impact of the seven-valent pneumococcal conjugate vaccine and the role of water supply.

BACKGROUND: Alaska Native (AN) children, especially those in the Yukon-Kuskokwim region (YK-AN children), suffer some of the highest rates of invasive pneumococcal disease (IPD) in the world. Rates of IPD declined after statewide introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in 2001, but increased in subsequent years. METHODS: Population-based laboratory surveillance data (1986-2007) for invasive Streptococcus pneumoniae infection in Alaskan children <5 years old were used to evaluate the association of IPD rates and serotype distribution with immunization, socioeconomic status, and in-home water service. RESULTS: Introduction of PCV7 vaccine resulted in elimination of IPD caused by vaccine serotypes, but was followed by increasing rates of IPD caused by nonvaccine serotypes. Among YK-AN children IPD rates dropped by 60%, but then rose due to non-PCV7 serotypes to levels 5- to 10-fold higher than rates in non-YK-AN children and non-AN children. IPD rates in YK-AN children were twice as high in villages where <10% of houses had in-home piped water compared with villages where more than 80% of houses had in-home piped water (390 cases/100,000 vs. 146 cases/100,000, P = 0.008). CONCLUSIONS: High IPD rates in Alaska are associated with lack of in-home piped water (controlling for household crowding and per capita income). The effect of in-home piped water is most likely mediated through reduced water supply leading to limitations on handwashing.