3 research outputs found
Changing patterns of undiagnosed HIV infection in the Netherlands: Who benefits most from intensified HIV test and treat policies?
Objectives: To estimate HIV prevalence, the number of people living with HIV/AIDS (PLWHA) and the undiagnosed proportion in the Netherlands for 2012, and to compare these with published 2007 estimates. Design: Synthesis of all available data sources. Methods: Multi-Parameter Evidence Synthesis (MPES) was used to obtain estimates in mutually exclusive key populations at higher risk in three geographical regions (Amsterdam, Rotterdam, rest of the Netherlands). Data sources included HIV prevalence surveys, diagnoses at STI clinics, and registered cases in HIV care. Group specific estimates were reported as Bayesian posterior medians and 95% credible intervals (CrI). Results: The 2012 model estimated 24,350 PLWHA (95% CrI 20,420-31,280) aged 15-70 years; 2,906 (+14%) more than in 2007. The estimated population HIV prevalence was 0.20% (95% CrI 0.17-0.26%). The overall proportion of undiagnosed HIV was lower in 2012 (34%, 95% CrI 22-49%) compared to 2007 (40%, 95% CrI 25-55%). After MSM, migrants from sub-Saharan Africa and the Caribbean formed the largest groups of PLWHA, but proportions of undiagnosed HIV remained high in these groups, 48% and 44% respectively. Amsterdam had lowest proportions undiagnosed for most key populations at higher risk, including MSM and migrants. Conclusions: In 2012, the number of PLWHA was higher compared to 2007, while the proportion of undiagnosed HIV was lower, especially among MSM. Higher HIV testing rates, earlier treatment, and an improved life expectancy may explain these differences. HIV interventions need to be expanded in all key populations at higher risk, with special focus on migrants and key populationsliving outside of Amsterdam. Copyright
Dietary exposure to polychlorinated biphenyls and dioxins from infancy until adulthood: A comparison between breast-feeding, toddler, and long-term exposure
Food is the major source for polychlorinated biphenyl (PCB) and dioxin
accumulation in the human body. Therefore, investigating food habits from
early ages until reproductive age (25 years) is important in order to
assess exposure risk for the next generation. The objective of this study
was to assess the PCB/dioxin exposure and the relative contribution of
different foods to total exposure during preschool age. Particularly, the
importance of lactational PCB/dioxin exposure vs. dietary exposure until
adulthood was investigated. A cohort of 207 children was studied from
birth until preschool age. Based on 3 planar PCBs and 17
2,3,7,8-substituted dibenzo-para-dioxins (PCDDs) and dibenzofurans (PCDFs)
measured in breast milk, a model was developed to calculate the cumulative
toxic equivalent (TEQ) intake during breast-feeding (0-1 year). In 3.
5-year-old children, daily dietary intake of planar PCB-TEQ and dioxin-TEQ
was measured with a validated food questionnaire. Cumulative TEQ intake
from 1 to 5 years was estimated using the PCB- and dioxin-TEQ intake
measured with the food questionnaire. Cumulative TEQ intake from 6 to 25
years was estimated using national food consumption and contamination data
of PCB- and dioxin-TEQ intake. In toddlers, dairy products contributed 43%
to PCB-TEQ and 50% to dioxin-TEQ intake. Meat and meat products
contributed 14% and 19%, respectively, and processed foods 23% and 15%,
respectively. Breast-feeding for 6 months contributed to the cumulative
PCB/dioxin TEQ intake until 25 years of age, 12% in boys and 14% in girls.
The daily TEQ intake per kilogram body weight is 50 times higher in
breast-fed infants and three times higher in toddlers than in adults.
Long-term dietary exposure to PCBs and dioxins in men and women is partly
due to breast-feeding (12 and 14%, respectively). After weaning, dairy
products, processed foods, and meat are major contributors of PCB and
dioxin accumulation until reproductive age. Instead of discouraging
breast-feeding, maternal transfer of PCBs and dioxins to the next
generation must be avoided by enforcement of strict regulations for PCB
and dioxin discharge and by reducing consumption of animal products and
processed foods in all ages
Effects of Population Based Screening for Chlamydia Infections in The Netherlands Limited by Declining Participation Rates
Background: A large trial to investigate the effectiveness of population based screening for chlamydia infections was conducted in the Netherlands in 2008-2012. The trial was register based and consisted of four rounds of screening of women and men in the age groups 16-29 years in three regions in the Netherlands. Data were collected on participation rates and positivity rates per round. A modeling study was conducted to project screening effects for various screening strategies into the future. Methods and Findings: We used a stochastic network simulation model incorporating partnership formation and dissolution, aging and a sexual life course perspective. Trends in baseline rates of chlamydia testing and treatment were used to describe the epidemiological situation before the start of the screening program. Data on participation rates was used to describe screening uptake in rural and urban areas. Simulations were used to project the effectiveness of screening on chlamydia prevalence for a time period of 10 years. In addition, we tested alternative screening strategies, such as including only women, targeting different age groups, and biennial screening. Screening reduced prevalence by about 1% in the first two screening rounds and leveled off after that. Extrapolating observed participation rates into the future indicated very low participation in the long run. Alternative strategies only marginally changed the effectiveness of screening. Higher participation rates as originally foreseen in the program would have succeeded in reducing chlamydia prevalence to very low levels in the long run. Conclusions: Decreasing participation rates over time profoundly impact the effectiveness of population based screening for chlamydia infections. Using data from several consecutive rounds of screening in a simulation model enabled us to assess the future effectiveness of screening on prevalence. If participation rates cannot be kept at a sufficient level, the effectiveness of screening on prevalence will remain limited