Ongoing transmission of lymphatic filariasis in Samoa 4.5 years after one round of triple-drug mass drug administration.

BACKGROUND: Lymphatic filariasis (LF) remains a significant global issue. To eliminate LF as a public health problem, the World Health Organization (WHO) recommends multiple rounds of mass drug administration (MDA). In certain scenarios, including when elimination targets have not been met with two-drug MDA, triple-drug MDA (using ivermectin, diethylcarbamazine and albendazole) is recommended. In this study, we report on antigen (Ag) and microfilaria (Mf) prevalence in eight primary sampling units (PSUs) in Samoa 4.5 years after one round of triple-drug MDA. METHODOLOGY: In 2023, community surveys were conducted in eight PSUs that had been surveyed previously in 2018 (between 1.5 and 3.5 months post triple-drug MDA) and 2019 (six to eight-months post triple-drug MDA). Fifteen houses were randomly selected in each PSU with household members aged ≥ 5 years invited to participate. Blood samples were tested for Ag and Mf. PRINCIPAL FINDINGS: Ag-positive participants were observed in six of the eight PSUs, and Ag prevalence was significantly above the 1% threshold in four PSUs. The presence of Mf-positive participants in five PSUs confirms the presence of residual active infections. CONCLUSIONS/SIGNIFICANCE: This study provides evidence of persistent LF transmission in Samoa 4.5 years after one round of triple-drug MDA, confirming that one round was insufficient for interruption of transmission in this setting. Our findings highlight the negative impact of delaying MDA rounds, for example, due to public health emergencies.

Accelerometer-Based Estimates of Physical Activity and Sedentary Time Among Samoan Adults.

BACKGROUND: The prevalence of obesity-related cardiometabolic disease in Samoa is among the highest globally. While physical activity is a modifiable risk factor for obesity-related disease, little is known about physical activity levels among adult Samoans. Using wrist-worn accelerometer-based devices, this study aimed to characterize physical activity among Samoan adults. METHODS: Samoan adults (n = 385; 55% female, mean [SD] age 52 [10] y) wore Actigraph GT3X+ devices for 7 to 10 days. General linear models were used to examine mean daily minutes of sedentary time, light physical activity, and moderate to vigorous physical activity by various participant characteristics. RESULTS: Time spent in moderate to vigorous physical activity did not differ statistically between men (88 [5] min; 95% confidence interval [CI], 80-97) and women (78 [4] min; 95% CI, 70-86; P = .08). Women, however, spent more time than men in light physical activity: 380 (7) minutes (95% CI, 367-393) versus 344 (7) minutes (95% CI, 329-358; P < .001). While there were no differences in physical activity by census region, education, or occupation among women, men in urban areas spent significantly less time in moderate to vigorous physical activity than those in peri-urban and rural areas (P = .015). Women with class II/III obesity spent more time in sedentary activities than those with healthy weight or overweight/class I obesity (P = .048). CONCLUSIONS: This study characterizes physical activity among Samoan adults and highlights variation by sex, urbanicity, and weight status. In providing initial device-measured estimates of physical activity in Samoa, this analysis establishes a baseline from which the success of future attempts to intervene on physical activity may be assessed.

Associations of childhood BMI traits with blood pressure and glycated haemoglobin in 6-9-year-old Samoan children.

INTRODUCTION: Prevalence and risk factors for elevated glycated haemoglobin (HbA1c) and blood pressure (BP) are poorly understood among Pacific children. We examined associations of HbA1c and BP in 6-9 year-olds with body mass index (BMI) at ages 2, 5, and BMI velocity between 2-9 years in Samoa. METHODS: HbA1c (capillary blood) and BP were measured in n = 410 Samoan children who were part of an ongoing cohort study. Multilevel models predicted BMI trajectory characteristics. Generalized linear regressions assessed associations of childhood characteristics and BMI trajectories with HbA1c and BP treated as both continuous and categorical outcomes. Primary caregiver-reported childhood characteristics were used as covariates. RESULTS: Overall, 12.90% (n = 53) of children had high HbA1c (≥5.7%) and 33.17% (n = 136) had elevated BP. BMI at 5-years and BMI velocity were positively associated with high HbA1c prevalence in males. A 1 kg/m2 per year higher velocity was associated with a 1.71 (95% CI: 1.07, 2.75) times higher prevalence of high HbA1c. In females, higher BMI at 5-years and greater BMI velocity were associated with higher BP at 6-9 years (95% CI: 1.12, 1.40, and 1.42, 2.74, respectively). CONCLUSION: Monitoring childhood BMI trajectories may inform cardiometabolic disease screening and prevention efforts in this at-risk population.

Scabies prevalence after ivermectin-based mass drug administration for lymphatic filariasis, Samoa 2018-2019.

BACKGROUND: Scabies is a common skin infestation caused by the Sarcoptes scabei mite. Ivermectin, one of three drugs used in mass drug administration (MDA) for lymphatic filariasis, is also effective for treating scabies. Ivermectin-based MDA was first conducted in Samoa in August 2018, with ivermectin being offered to those aged ≥5 years. Here, we report scabies prevalence in Samoa after MDA. METHODS: We conducted household surveys 1.5-3.5 months (Survey 1) and 6-8 months (Survey 2) after the 2018 MDA in 35 primary sampling units. We conducted clinical examination for scabies-like rash and used International Alliance for the Control of Scabies classification criteria. We estimated scabies prevalence by age, gender and region. Multivariable logistic regression was used to assess factors associated with prevalence. RESULTS: We surveyed 2868 people (499 households) and 2796 people (544 households) aged 0-75 years in Surveys 1 and 2, respectively. Scabies prevalence increased from 2.4% (95% CI 2.1-2.7%) to 4.4% (95% CI 4.0-4.9%) between surveys. Scabies was associated with younger age (0-4 years: aOR 3.5 [2.9-4.2]; 5-15 years: aOR 1.6 [1.4-1.8] compared to ≥16 years), female gender (aOR 1.2 [95% CI 1.1-1.4]; region (aOR range from 1.4 [1.1-1.7] to 2.5 [2.1-3.1] between regions), large households (aOR 2.6 [2.0-3.4] households ≥13), and not taking MDA in 2018 (aOR 1.3 [95% CI 1.1-1.6]). CONCLUSIONS: We found moderate prevalence of scabies in two population-representative surveys conducted within 8 months of the 2018 MDA for lymphatic filariasis. Prevalence appeared to increase between the surveys, and ongoing surveillance is recommended, particularly in young children.

The roles of emergency medical teams in response to Samoa's 2019 measles outbreak.

Problem: On 15 November 2019, Samoa's Government declared a state of emergency in response to a rapidly worsening measles outbreak. The outbreak overwhelmed Samoa's health system, necessitating international assistance, including from emergency medical teams (EMTs). Context: Measles spread globally throughout 2019, with cases rising by more than 300% in the first quarter of 2019, as compared with 2018. Given Samoa's low immunization coverage with a measles-containing vaccine at the time, at 40% for the first dose and 28% for the second, the country was soon overwhelmed with measles cases, hospitalizations and deaths. Action: Following a request for international assistance, 18 EMTs from around the world deployed to Samoa, bringing more than 550 additional clinical, public health and logistics personnel to the country's measles response. Working alongside Samoan health workers, EMTs provided critical surge assistance in clinical management, vaccination, surveillance, infection prevention and control, risk communication and community engagement, and mental health and psychosocial support. Outcome: A total of 1867 hospitalized measles patients were treated from 30 September 2019 to 13 January 2020, with 83 measles-related deaths recorded. EMTs provided essential surge support across Samoa's health system during the most acute phase of the response, helping to care for the ill and control the outbreak. Discussion: Samoa's measles response triggered a large-scale and unique EMT activation, with teams integrated into Samoa's hospitals and health centres. The response demonstrated the critical role that EMTs can play in outbreak response and the importance of strong coordination to ensure optimal use of international clinical surge support by a health system in crisis.

CREBRF missense variant rs373863828 has both direct and indirect effects on type 2 diabetes and fasting glucose in Polynesian peoples living in Samoa and Aotearoa New Zealand.

INTRODUCTION: The minor allele of a missense variant, rs373863828, in CREBRF is associated with higher body mass index (BMI), lower fasting glucose, and lower odds of type 2 diabetes. rs373863828 is common in Pacific Island populations (minor allele frequency (MAF) 0.096-0.259) but rare in non-Pacific Island populations (MAF <0.001). We examined the cross-sectional associations between BMI and rs373863828 in type 2 diabetes and fasting glucose with a large sample of adults of Polynesian ancestries from Samoa, American Samoa, and Aotearoa New Zealand, and estimated the direct and indirect (via BMI) effects of rs373863828 on type 2 diabetes and fasting glucose. RESEARCH DESIGN AND METHODS: We regressed type 2 diabetes and fasting glucose on BMI and rs373863828 stratified by obesity, regressed type 2 diabetes and fasting glucose on BMI stratified by rs373863828 genotype, and assessed the effects of rs373863828 on type 2 diabetes and fasting glucose with path analysis. The regression analyses were completed separately in four samples that were recruited during different time periods between 1990 and 2010 and then the results were meta-analyzed. All samples were pooled for the path analysis. RESULTS: Association of BMI with type 2 diabetes and fasting glucose may be greater in those without obesity (OR=7.77, p=0.015 and ß=0.213, p=9.53×10-5, respectively) than in those with obesity (OR=5.01, p=1.12×10-9 and ß=0.162, p=5.63×10-6, respectively). We did not observe evidence of differences in the association of BMI with type 2 diabetes or fasting glucose by genotype. In the path analysis, the minor allele has direct negative (lower odds of type 2 diabetes and fasting glucose) and indirect positive (higher odds of type 2 diabetes and fasting glucose) effects on type 2 diabetes risk and fasting glucose, with the indirect effects mediated through a direct positive effect of rs373863828 on BMI. CONCLUSIONS: There may be a stronger effect of BMI on fasting glucose in Polynesian individuals without obesity than in those with obesity. Carrying the rs373863828 minor allele does not decouple higher BMI from higher odds of type 2 diabetes.

Tobacco smoking initiation among students in Samoa and health concerns.

BACKGROUND: High prevalence of tobacco smoking among young students remains a serious health concern given the positive association between smoking and NCDs. More recently, some studies also noted young smokers were more likely to get infected with COVID-19 compared to non-smokers. This study aims to assess the factors that influence smoking uptake among young students in Samoa. Findings from this study will provide valuable insight to policymakers and health authorities on policies and strategies to combat smoking among youth in Samoa and the Pacific Island Countries (PICs). METHODS: The 2017 Global Youth Tobacco Survey data of Samoa, available from the World Health Organization is used in the analysis. We use the multinominal logistic model to investigate the effects of socio-economic and demographics factors on young students' uptake of smoking in Samoa. RESULT: The main findings of this study indicate that sex, age, friendship, parental smoking, family discussion, outside influence, pocket money, and mother's education are important determinants of tobacco smoking initiation among youths in Samoa. CONCLUSION: Our findings contribute towards the evidence of the imperative health impact of friends, parents, and public smoking on students in Samoa. This warrants strategies that are effective in discouraging parents from smoking and implement measures that prevent smoking in public places. Moreover, educational efforts, particularly those that encourage more discussion at home settings on the harmful effects of smoking are strongly recommended. Parents are strongly encouraged to regularly monitor children's spending behaviour.

Cancer Incidence in Samoa: A 10-Year Retrospective Survey (2007-2016).

Samoa is not immune to the growing global incidence of cancer, which is disproportionately high in low- and middle-income countries. As a preliminary step to upscale our population-based cancer registry initiatives in Samoa, we conducted a 10-year survey of cancer incidences in Samoa from 2007 to 2016. We reviewed all laboratory and clinically confirmed cases of cancer from 2007 to 2016 covering both government and nongovernment facilities. Cancer incidence increased steadily from 2007 (28.5 per 100 000) to 2012 (67.1 per 100 000). The incidence rate decreased in 2013 (from 67.1 cases in 2012 to 51.4 cases per 100 000 in 2013); and in 2015 (from 65.1 cases in 2014 to 54.3 cases per 100 000 in 2015). From 2012 to 2016, the incidence rate fluctuates between 50 and 65 cases per 100 000. Cancers of female genitalia, breast, and digestive system were the most common types in female and males, respectively.

A missense variant in CREBRF, rs373863828, is associated with fat-free mass, not fat mass in Samoan infants.

BACKGROUND/OBJECTIVES: In Samoa, where 80% of the adult population is living with obesity, understanding the determinants of adiposity and growth during infancy may inform prevention efforts. We examined the association of a missense variant, rs373863828, in the CREBRF gene with body composition in Samoan infants. Adults with one or more copies of the rs373863828 minor allele (A) have higher odds of obesity, based on body-mass index (BMI), but paradoxically decreased odds of diabetes compared to those without the allele. Our study may offer novel insight into the natural history and pathogenesis of this unexpected relationship. SUBJECTS/METHODS: In a prospective study, we measured body composition in early infancy, and at 2- and 4-months of age using anthropometry and dual-energy x-ray absorptiometry (DXA). We genotyped subjects at the CREBRF rs373863828 locus and compared infants with (AA/AG) and without (GG) the variant. In longitudinal analyses, we calculated the absolute change in each outcome from the early infant to the 4-month assessment, adjusting for baseline and other covariates. RESULTS: In cross-sectional analyses, there was no significant difference in infant BMI or fat mass by genotype. After adjusting for covariates, infants with the variant had 4.0 ± 1.8 g more bone mass (p = 0.026) and 210.9 ± 79.6 g more lean mass (p = 0.009) at 4-months and accumulated 176.9 ± 73.0 g more lean mass between the early infant and 4-month assessment (p = 0.017). CONCLUSIONS: The CREBRF rs373863828 minor allele (A) was not associated with increased BMI or adiposity in Samoan infants, but instead with increased lean and bone mass. Our findings suggest that lean (i.e., muscle) and bone mass accretion should be explored as pathways to explain the "protective" effect of the CREBRF variant against diabetes.

The rising relative and absolute incidence of uterine cancer in specific populations.

OBJECTIVE: To assess the contemporary incidence of cancers using American Samoa as a learning set for insights into similar populations. METHODS: A retrospective observational analysis of de-identified data held in public-access databases (2004-2014) and data on uterine cancer from a hospital, both in American Samoa (2015-2016). RESULTS: There were 341 new cases of cancer in 2004-2014 (111 per 100 000 women/year), including breast (20.2%), uterine (19.4%), and cervical (5.0%); and 287 in 2011-2015 (103 per 100 000 women/year), including uterine (24.0%), breast (18.5%), and cervical (5.2%). Uterine cancer increased from 21.4 to 60.3 per 100 000 women/year, becoming the most common cancer in American Samoa. In 2011-2015, the incidence-rate ratio of uterine cancer to other cancers in American Samoa was 1.3-, 3.8-, 4.6-, 7.7-, and 23-fold higher than breast, colon, cervical, ovarian, and lung cancer, respectively. Among the most recent cases (n=33), median age was 55 years (10 [30.3%] <50 years), median BMI was 38.2; and 11 (33.3%) cases had grade 3 histology. CONCLUSION: The pattern of cancers in American Samoa differs from that in the US mainland. The findings reflect significant changes in cancer incidence. Cancer control programs should evaluate the potential of uterine screening in accordance with their community's needs and characteristics.

ECHS1 disease in two unrelated families of Samoan descent: Common variant - rare disorder.

Mutations in the short-chain enoyl-CoA hydratase (SCEH) gene, ECHS1, cause a rare autosomal recessive disorder of valine catabolism. Patients usually present with developmental delay, regression, dystonia, feeding difficulties, and abnormal MRI with bilateral basal ganglia involvement. We present clinical, biochemical, molecular, and functional data for four affected patients from two unrelated families of Samoan descent with identical novel compound heterozygous mutations. Family 1 has three affected boys while Family 2 has an affected daughter, all with clinical and MRI findings of Leigh syndrome and intermittent episodes of acidosis and ketosis. WES identified a single heterozygous variant in ECHS1 at position c.832G > A (p.Ala278Thr). However, western blot revealed significantly reduced ECHS1 protein for all affected family members. Decreased SCEH activity in fibroblasts and a mild increase in marker metabolites in urine further supported ECHS1 as the underlying gene defect. Additional investigations at the DNA (aCGH, WGS) and RNA (qPCR, RT-PCR, RNA-Seq, RNA-Array) level identified a silent, common variant at position c.489G > A (p.Pro163=) as the second mutation. This substitution, present at high frequency in the Samoan population, is associated with decreased levels of normally spliced mRNA. To our understanding, this is the first report of a novel, hypomorphic allele c.489G > A (p.Pro163=), associated with SCEH deficiency.

Lymphatic filariasis epidemiology in Samoa in 2018: Geographic clustering and higher antigen prevalence in older age groups.

BACKGROUND: Samoa conducted eight nationwide rounds of mass drug administration (MDA) for lymphatic filariasis (LF) between 1999 and 2011, and two targeted rounds in 2015 and 2017 in North West Upolu (NWU), one of three evaluation units (EUs). Transmission Assessment Surveys (TAS) were conducted in 2013 (failed in NWU) and 2017 (all three EUs failed). In 2018, Samoa was the first in the world to distribute nationwide triple-drug MDA using ivermectin, diethylcarbamazine, and albendazole. Surveillance and Monitoring to Eliminate LF and Scabies from Samoa (SaMELFS Samoa) is an operational research program designed to evaluate the effectiveness of triple-drug MDA on LF transmission and scabies prevalence in Samoa, and to compare the usefulness of different indicators of LF transmission. This paper reports results from the 2018 baseline survey and aims to i) investigate antigen (Ag) prevalence and spatial epidemiology, including geographic clustering; ii) compare Ag prevalence between two different age groups (5-9 years versus ≥10 years) as indicators of areas of ongoing transmission; and iii) assess the prevalence of limb lymphedema in those aged ≥15 years. METHODS: A community-based cluster survey was conducted in 30 randomly selected and five purposively selected clusters (primary sampling units, PSUs), each comprising one or two villages. Participants were recruited through household surveys (age ≥5 years) and convenience surveys (age 5-9 years). Alere Filariasis Test Strips (FTS) were used to detect Ag, and prevalence was adjusted for survey design and standardized for age and gender. Adjusted Ag prevalence was estimated for each age group (5-9, ≥10, and all ages ≥5 years) for random and purposive PSUs, and by region. Intraclass correlation (ICC) was used to quantify clustering at regions, PSUs, and households. RESULTS: A total of 3940 persons were included (1942 children aged 5-9 years, 1998 persons aged ≥10 years). Adjusted Ag prevalence in all ages ≥5 years in randomly and purposively selected PSUs were 4.0% (95% CI 2.8-5.6%) and 10.0% (95% CI 7.4-13.4%), respectively. In random PSUs, Ag prevalence was lower in those aged 5-9 years (1.3%, 95% CI 0.8-2.1%) than ≥10 years (4.7%, 95% CI 3.1-7.0%), and poorly correlated at the PSU level (R-square = 0.1459). Adjusted Ag prevalence in PSUs ranged from 0% to 10.3% (95% CI 5.9-17.6%) in randomly selected and 3.8% (95% CI 1.3-10.8%) to 20.0% (95% CI 15.3-25.8%) in purposively selected PSUs. ICC for Ag-positive individuals was higher at households (0.46) compared to PSUs (0.18) and regions (0.01). CONCLUSIONS: Our study confirmed ongoing transmission of LF in Samoa, in accordance with the 2017 TAS results. Ag prevalence varied significantly between PSUs, and there was poor correlation between prevalence in 5-9 year-olds and older ages, who had threefold higher prevalence. Sampling older age groups would provide more accurate estimates of overall prevalence, and be more sensitive for identifying residual hotspots. Higher prevalence in purposively selected PSUs shows local knowledge can help identify at least some hotspots.

Supporting elimination of lymphatic filariasis in Samoa by predicting locations of residual infection using machine learning and geostatistics.

The global elimination of lymphatic filariasis (LF) is a major focus of the World Health Organization. One key challenge is locating residual infections that can perpetuate the transmission cycle. We show how a targeted sampling strategy using predictions from a geospatial model, combining random forests and geostatistics, can improve the sampling efficiency for identifying locations with high infection prevalence. Predictions were made based on the household locations of infected persons identified from previous surveys, and environmental variables relevant to mosquito density. Results show that targeting sampling using model predictions would have allowed 52% of infections to be identified by sampling just 17.7% of households. The odds ratio for identifying an infected individual in a household at a predicted high risk compared to a predicted low risk location was 10.2 (95% CI 4.2-22.8). This study provides evidence that a 'one size fits all' approach is unlikely to yield optimal results when making programmatic decisions based on model predictions. Instead, model assumptions and definitions should be tailored to each situation based on the objective of the surveillance program. When predictions are used in the context of the program objectives, they can result in a dramatic improvement in the efficiency of locating infected individuals.

The potential impact of a recent measles epidemic on COVID-19 in Samoa.

BACKGROUND: The pandemic of COVID-19 has occurred close on the heels of a global resurgence of measles. In 2019, an unprecedented epidemic of measles affected Samoa, requiring a state of emergency to be declared. Measles causes an immune amnesia which can persist for over 2 years after acute infection and increases the risk of a range of other infections. METHODS: We modelled the potential impact of measles-induced immune amnesia on a COVID-19 epidemic in Samoa using data on measles incidence in 2018-2019, population data and a hypothetical COVID-19 epidemic. RESULTS: The young population structure and contact matrix in Samoa results in the most transmission occurring in young people < 20 years old. The highest rate of death is the 60+ years old, but a smaller peak in death may occur in younger people, with more than 15% of total deaths in the age group under 20 years old. Measles induced immune amnesia could increase the total number of cases by 8% and deaths by more than 2%. CONCLUSIONS: Samoa, which had large measles epidemics in 2019-2020 should focus on rapidly achieving high rates of measles vaccination and enhanced surveillance for COVID-19, as the impact may be more severe due to measles-induced immune paresis. This applies to other severely measles-affected countries in the Pacific, Europe and elsewhere.

Prevalence of syphilis, gonorrhoea and chlamydia in women in Fiji, the Federated States of Micronesia, Papua New Guinea and Samoa, 1995-2017: Spectrum-STI model estimates.

OBJECTIVE: To estimate prevalence levels of and time trends for active syphilis, gonorrhoea and chlamydia in women aged 15-49 years in four countries in the Pacific (Fiji, the Federated States of Micronesia [FSM], Papua New Guinea [PNG] and Samoa) to inform surveillance and control strategies for sexually transmitted infections (STIs). METHODS: The Spectrum-STI model was fitted to data from prevalence surveys and screenings of adult female populations collected during 1995-2017 and adjusted for diagnostic test performance and to account for undersampled high-risk populations. For chlamydia and gonorrhoea, data were further adjusted for age and differences between urban and rural areas. RESULTS: Prevalence levels were estimated as a percentage (95% confidence interval). In 2017, active syphilis prevalence was estimated in Fiji at 3.89% (2.82 to 5.06), in FSM at 1.48% (0.93 to 2.16), in PNG at 3.91% (1.67 to 7.24) and in Samoa at 0.16% (0.07 to 0.37). For gonorrhoea, the prevalence in Fiji was 1.63% (0.50 to 3.87); in FSM it was 1.59% (0.49 to 3.58); in PNG it was 11.0% (7.25 to 16.1); and in Samoa it was 1.61% (1.17 to 2.19). The prevalence of chlamydia in Fiji was 24.1% (16.5 to 32.7); in FSM it was 23.9% (18.5 to 30.6); in PNG it was 14.8% (7.39 to 24.7); and in Samoa it was 30.6% (26.8 to 35.0). For each specific disease within each country, the 95% confidence intervals overlapped for 2000 and 2017, although in PNG the 2017 estimates for all three STIs were below the 2000 estimates. These patterns were robust in the sensitivity analyses. DISCUSSION: This study demonstrated a persistently high prevalence of three major bacterial STIs across four countries in WHO's Western Pacific Region during nearly two decades. Further strengthening of strategies to control and prevent STIs is warranted.

Comparing age and sex trends of chlamydia, gonorrhoea, hepatitis and syphilis infections in Samoa in 2012 and 2017.

In Samoa, the seroprevalence rates of sexually transmitted infections other than HIV have been endemically high over the past decade, despite years of prevention programming. Odds ratio and χ2 tests were conducted to compare the rates of positivity of chlamydia, gonorrhoea, hepatitis B and C, and syphilis across age groups from 2012 and 2017 surveillance data in Samoa. Young people aged 15-19 years were significantly more likely to have a chlamydia infection compared to all other age groups in both 2012 and 2017. Hepatitis B infections were more common in males and those aged 30 and above in both 2012 and 2017. Hepatitis C had no significant differences in age, but it was more common in males in 2012 and more common in females in 2017. Older age groups (aged 45 and above) were more likely to have a positive syphilis test in both 2014 and 2017 when compared to those aged 15-24 years. The results of this analysis confirm previously observed trends in Samoa for younger age groups' prevalence of chlamydia and gonorrhoea, and for older age groups' prevalence of hepatitis B and C. But the analysis also unexpectedly found that older age groups (aged 45 and above) are more likely to test positive for syphilis (for years 2014 and 2017). Further studies are needed to assess behavioural risk factors associated with older populations to explain the increase in risk and to design interventions suited to this demographic.

Association between the spread of COVID-19 and weather-climatic parameters.

OBJECTIVE: To explore whether the climate has played a role in the COVID-19 outbreak, we compared virus lethality in countries closer to the Equator with others. Lethality in European territories and in territories of some nations with a non-temperate climate was also compared. MATERIALS AND METHODS: Lethality was calculated as the rate of deaths in a determinate moment from the outbreak of the pandemic out of the total of identified positives for COVID-19 in a given area/nation, based on the COVID-John Hopkins University website. Lethality of countries located within the 5th parallels North/South on 6 April and 6 May 2020, was compared with that of all the other countries. Lethality in the European areas of The Netherlands, France and the United Kingdom was also compared to the territories of the same nations in areas with a non-temperate climate. RESULTS: A lower lethality rate of COVID-19 was found in Equatorial countries both on April 6 (OR=0.72 CI 95% 0.66-0.80) and on May 6 (OR=0.48, CI 95% 0.47-0.51), with a strengthening over time of the protective effect. A trend of higher risk in European vs. non-temperate areas was found on April 6, but a clear difference was evident one month later: France (OR=0.13, CI 95% 0.10-0.18), The Netherlands (OR=0.5, CI 95% 0.3-0.9) and the UK (OR=0.2, CI 95% 0.01-0.51). This result does not seem to be totally related to the differences in age distribution of different sites. CONCLUSIONS: The study does not seem to exclude that the lethality of COVID-19 may be climate sensitive. Future studies will have to confirm these clues, due to potential confounding factors, such as pollution, population age, and exposure to malaria.

On the limitations of barriers: Social visibility and weight management in Cuba and Samoa.

Obesity is an enduring global health challenge. Researchers have struggled to understand the barriers and facilitators of weight loss. Using a cross-cultural comparative approach, we move away from a barriers approach to analyze obesity and overweight through the lens of social visibility to understand the persistent failure of most obesity interventions. Drawing on ethnographic data from Cuba and Samoa collected between 2010 and 2017, we argue that social visibility is a framework for analyzing some of the reasons why people do not participate in weight management programs when they have high rates of health literacy and access to free or low-cost programming. Comparing these two places with very different histories of obesity interventions, we trace how weight management practices make people socially visible (in positive and negative ways), specifically analyzing how gender and economic inequalities shape the sociality of obesity. Our findings show that regardless of barriers and facilitators of weight loss at an individual and population level, the ways weight loss activities are incorporated into or conflict with the social dynamics of everyday life can have a profound effect on weight management. Employing visibility as a analytic framework de-individualizes weight responsibility, providing a contextual way to understand the difficulties people face when they manage their weight.