Washeteria closures, infectious disease and community health in rural Alaska: a review of clinical data in Kivalina, Alaska

Background. Kivalina is a northwest Alaska barrier island village of 400 people vulnerable to storm surges exacerbated recently by delayed winter sea and shore ice formation. The village has no in-home piped water or sewage; the “washeteria” is the only structure providing public showers, laundry facilities and flush toilets. In October 2004, a storm damaged the washeteria septic system resulting in prolonged facility closures. We assessed rates of gastrointestinal, respiratory and skin infections potentially impacted by prolonged washeteria closures. Methods. We obtained washeteria closure dates from 2003 to July 2009 and defined >7 day closure as prolonged. We received de-identified data on all Kivalina clinic visits from 2003 to 2009 and selected visits with ICD-9 diagnosis codes for respiratory, skin, or gastrointestinal infection; subsequent same patient/same illness-category visits within 14 days were excluded. We compared annual visit rates, for all ages combined, before (2003–2004) and after (2005–2009) the “2004” storm. Results. The washeteria had prolonged closures for 34 days (4.7%) in the 2 years 2003–2004 and 864 days (51.7%) between January 2005 and July 2009. Closures ranged from 8 to 248 days. Respiratory infection rates declined significantly from 1.32 visits/person/year in the 2003–2004 period to 0.99 visits/person/year in the 2005–2009 period. There was a significant increase in skin infection rates after 2004, peaking at 0.28 visits/person/year in 2007 and then declining significantly to 0.15 visits/person/year in 2009. Gastrointestinal infection rates remained stable and low throughout (average: 0.05 visits/person/year). No temporal association was observed between respiratory, gastrointestinal or skin infection rates and prolonged washeteria closures. Conclusion. The Kivalina washeteria was closed frequently and for extended periods between 2005 and 2009. Initial closures possibly resulted in increased skin infection rates. No increase in respiratory or gastrointestinal infections was noted. Evaluation of community adaptations to closures and other factors (e.g. childhood pneumococcal vaccination) would expand understanding of these findings

Methicillin-Resistant Staphylococcus aureus Carriage and Risk Factors for Skin Infections, Southwestern Alaska, USA

Skin infection risk was increased among MRSA nasal carriers

Impact of the 13-valent pneumococcal conjugate vaccine (pcv13) on invasive pneumococcal disease and carriage in Alaska

AbstractBackgroundAlaska Native (AN) children have experienced high rates of invasive pneumococcal disease (IPD). In March 2010, PCV13 was introduced statewide in Alaska. We evaluated the impact of PCV13 on IPD in children and adults, 45 months after introduction.MethodsPneumococcal sterile site isolates, reported through state-wide surveillance, were serotyped using standard methods. We defined a pre-PCV13 time period 2005–2008 and post-PCV13 time period April 2010–December 2013; excluding Jan 2009–March 2010 because PCV13 was introduced pre-licensure in one high-risk region in 2009.ResultsAmong Alaska children <5 years, PCV13 serotypes comprised 65% of IPD in the pre-PCV13 period and 26% in the PCV13 period. Among all Alaska children <5 years, IPD rates decreased from 60.9 (pre) to 25.4 (post) per 100,000/year (P<0.001); PCV13 serotype IPD decreased from 37.7 to 6.4 (P<0.001). Among AN children <5 years, IPD rates decreased from 149.2 to 60.8 (P<0.001); PCV13 serotype IPD decreased from 87.0 to 17.4 (P<0.001); non-PCV13 serotype IPD did not change significantly. Among persons 5–17 and ≥45 years, the post-vaccine IPD rate was similar to the baseline period, but declined in persons 18–44 years (39%, P<0.001); this decline was similar in AN and non-AN persons (38%, P=0.016, 43%, P=0.014, respectively).ConclusionsForty-five months after PCV13 introduction, overall IPD and PCV13-serotype IPD rates had decreased 58% and 83%, respectively, in Alaska children <5 years of age when compared with 2005–2008. We observed evidence of indirect effect among adults with a 39% reduction in IPD among persons 18–44 years

International Circumpolar Surveillance System for Invasive Pneumococcal Disease, 1999–2005

Disease rates are high among indigenous persons in Arctic countries, and PCV7 has resulted in decreased rates in North American children

Changes in Invasive Pneumococcal Disease Caused by Streptococcus pneumoniae Serotype 1 following Introduction of PCV10 and PCV13: Findings from the PSERENADE Project

Streptococcus pneumoniae serotype 1 (ST1) was an important cause of invasive pneumococcal disease (IPD) globally before the introduction of pneumococcal conjugate vaccines (PCVs) containing ST1 antigen. The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project gathered ST1 IPD surveillance data from sites globally and aimed to estimate PCV10/13 impact on ST1 IPD incidence. We estimated ST1 IPD incidence rate ratios (IRRs) comparing the pre-PCV10/13 period to each post-PCV10/13 year by site using a Bayesian multi-level, mixed-effects Poisson regression and all-site IRRs using a linear mixed-effects regression (N = 45 sites). Following PCV10/13 introduction, the incidence rate (IR) of ST1 IPD declined among all ages. After six years of PCV10/13 use, the all-site IRR was 0.05 (95% credibility interval 0.04-0.06) for all ages, 0.05 (0.04-0.05) for <5 years of age, 0.08 (0.06-0.09) for 5-17 years, 0.06 (0.05-0.08) for 18-49 years, 0.06 (0.05-0.07) for 50-64 years, and 0.05 (0.04-0.06) for ≥65 years. PCV10/13 use in infant immunization programs was followed by a 95% reduction in ST1 IPD in all ages after approximately 6 years. Limited data availability from the highest ST1 disease burden countries using a 3+0 schedule constrains generalizability and data from these settings are needed

Global patterns in monthly activity of influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus: a systematic analysis

Background: Influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus are the most common viruses associated with acute lower respiratory infections in young children (<5 years) and older people (≥65 years). A global report of the monthly activity of these viruses is needed to inform public health strategies and programmes for their control. Methods: In this systematic analysis, we compiled data from a systematic literature review of studies published between Jan 1, 2000, and Dec 31, 2017; online datasets; and unpublished research data. Studies were eligible for inclusion if they reported laboratory-confirmed incidence data of human infection of influenza virus, respiratory syncytial virus, parainfluenza virus, or metapneumovirus, or a combination of these, for at least 12 consecutive months (or 52 weeks equivalent); stable testing practice throughout all years reported; virus results among residents in well-defined geographical locations; and aggregated virus results at least on a monthly basis. Data were extracted through a three-stage process, from which we calculated monthly annual average percentage (AAP) as the relative strength of virus activity. We defined duration of epidemics as the minimum number of months to account for 75% of annual positive samples, with each component month defined as an epidemic month. Furthermore, we modelled monthly AAP of influenza virus and respiratory syncytial virus using site-specific temperature and relative humidity for the prediction of local average epidemic months. We also predicted global epidemic months of influenza virus and respiratory syncytial virus on a 5° by 5° grid. The systematic review in this study is registered with PROSPERO, number CRD42018091628. Findings: We initally identified 37 335 eligible studies. Of 21 065 studies remaining after exclusion of duplicates, 1081 full-text articles were assessed for eligibility, of which 185 were identified as eligible. We included 246 sites for influenza virus, 183 sites for respiratory syncytial virus, 83 sites for parainfluenza virus, and 65 sites for metapneumovirus. Influenza virus had clear seasonal epidemics in winter months in most temperate sites but timing of epidemics was more variable and less seasonal with decreasing distance from the equator. Unlike influenza virus, respiratory syncytial virus had clear seasonal epidemics in both temperate and tropical regions, starting in late summer months in the tropics of each hemisphere, reaching most temperate sites in winter months. In most temperate sites, influenza virus epidemics occurred later than respiratory syncytial virus (by 0·3 months [95% CI −0·3 to 0·9]) while no clear temporal order was observed in the tropics. Parainfluenza virus epidemics were found mostly in spring and early summer months in each hemisphere. Metapneumovirus epidemics occurred in late winter and spring in most temperate sites but the timing of epidemics was more diverse in the tropics. Influenza virus epidemics had shorter duration (3·8 months [3·6 to 4·0]) in temperate sites and longer duration (5·2 months [4·9 to 5·5]) in the tropics. Duration of epidemics was similar across all sites for respiratory syncytial virus (4·6 months [4·3 to 4·8]), as it was for metapneumovirus (4·8 months [4·4 to 5·1]). By comparison, parainfluenza virus had longer duration of epidemics (6·3 months [6·0 to 6·7]). Our model had good predictability in the average epidemic months of influenza virus in temperate regions and respiratory syncytial virus in both temperate and tropical regions. Through leave-one-out cross validation, the overall prediction error in the onset of epidemics was within 1 month (influenza virus −0·2 months [−0·6 to 0·1]; respiratory syncytial virus 0·1 months [−0·2 to 0·4]). Interpretation: This study is the first to provide global representations of month-by-month activity of influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus. Our model is helpful in predicting the local onset month of influenza virus and respiratory syncytial virus epidemics. The seasonality information has important implications for health services planning, the timing of respiratory syncytial virus passive prophylaxis, and the strategy of influenza virus and future respiratory syncytial virus vaccination. Funding: European Union Innovative Medicines Initiative Respiratory Syncytial Virus Consortium in Europe (RESCEU)

Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in young children in 2015:a systematic review and modelling study

Background: We have previously estimated that respiratory syncytial virus (RSV) was associated with 22% of all episodes of (severe) acute lower respiratory infection (ALRI) resulting in 55 000 to 199 000 deaths in children younger than 5 years in 2005. In the past 5 years, major research activity on RSV has yielded substantial new data from developing countries. With a considerably expanded dataset from a large international collaboration, we aimed to estimate the global incidence, hospital admission rate, and mortality from RSV-ALRI episodes in young children in 2015. Methods: We estimated the incidence and hospital admission rate of RSV-associated ALRI (RSV-ALRI) in children younger than 5 years stratified by age and World Bank income regions from a systematic review of studies published between Jan 1, 1995, and Dec 31, 2016, and unpublished data from 76 high quality population-based studies. We estimated the RSV-ALRI incidence for 132 developing countries using a risk factor-based model and 2015 population estimates. We estimated the in-hospital RSV-ALRI mortality by combining in-hospital case fatality ratios with hospital admission estimates from hospital-based (published and unpublished) studies. We also estimated overall RSV-ALRI mortality by identifying studies reporting monthly data for ALRI mortality in the community and RSV activity. Findings: We estimated that globally in 2015, 33·1 million (uncertainty range [UR] 21·6–50·3) episodes of RSV-ALRI, resulted in about 3·2 million (2·7–3·8) hospital admissions, and 59 600 (48 000–74 500) in-hospital deaths in children younger than 5 years. In children younger than 6 months, 1·4 million (UR 1·2–1·7) hospital admissions, and 27 300 (UR 20 700–36 200) in-hospital deaths were due to RSV-ALRI. We also estimated that the overall RSV-ALRI mortality could be as high as 118 200 (UR 94 600–149 400). Incidence and mortality varied substantially from year to year in any given population. Interpretation: Globally, RSV is a common cause of childhood ALRI and a major cause of hospital admissions in young children, resulting in a substantial burden on health-care services. About 45% of hospital admissions and in-hospital deaths due to RSV-ALRI occur in children younger than 6 months. An effective maternal RSV vaccine or monoclonal antibody could have a substantial effect on disease burden in this age group

Risk Factors for Pneumococcal Colonization of the Nasopharynx in Alaska Native Adults and Children.

BACKGROUND: Alaska Native children have high invasive pneumococcal disease (IPD) rates, and lack of in-home running water has been shown to have a significant association with infection. Pneumococcal conjugate vaccines reduced IPD; however, this population saw substantial replacement disease and colonization with nonvaccine serotypes. We evaluated risk factors for nasopharyngeal pneumococcal colonization in Alaska Native adults and children. METHODS: We conducted annual surveys from 2008 through 2011 of residents of all ages in 8 rural Alaskan villages. Interviews were conducted, medical charts were reviewed, and nasopharyngeal swabs were cultured for Streptococcus pneumoniae. Multivariate logistic regression models were developed for 3 age groups (under 10 years, 10-17 years, and 18 years and older) to determine risk factors for colonization. RESULTS: We obtained 12 535 nasopharyngeal swabs from 4980 participants. Our population lived in severely crowded conditions, and 48% of households lacked in-home running water. In children \u3c10 \u3eyears, colonization was associated with lack of in-home running water, household crowding, and more children in the home. Pneumococcal vaccination status was not associated with colonization. In older children and adults, increased number of persons in the household was associated with pneumococcal colonization. CONCLUSIONS: Higher colonization prevalence may partially explain increased IPD rates seen in those lacking in-home water services. Improving availability of sanitation services and reducing household crowding may reduce the burden of IPD in this population