A simple model to quantitatively account for periodic outbreaks of the measles in the Dutch Bible Belt

In the Netherlands there has been nationwide vaccination against the measles since 1976. However, in small clustered communities of orthodox Protestants there is widespread refusal of the vaccine. After 1976, three large outbreaks with about 3000 reported cases of the measles have occurred among these orthodox Protestants. The outbreaks appear to occur about every twelve years. We show how a simple Kermack-McKendrick-like model can quantitatively account for the periodic outbreaks. Approximate analytic formulae to connect the period, size, and outbreak duration are derived. With an enhanced model we take the latency period in account. We also expand the model to follow how different age groups are affected. Like other researchers using other methods, we conclude that large scale underreporting of the disease must occur

Negative attitude and low intention to vaccinate universally against varicella among public health professionals and parents in the Netherlands: two internet surveys

Contains fulltext : 171030.pdf (publisher's version ) (Open Access)BACKGROUND: Prior to introduction of universal varicella vaccination, it is crucial to gain insight into the willingness to vaccinate among the population. This is because suboptimal national vaccination coverage might increase the age of infection in children, which will lead to higher complication rates. We studied the attitude and intention to vaccinate against varicella among Dutch public health professionals who execute the National Immunisation Programme (NIP), and parents. METHODS: Medical doctors and nurses of regional public health services (RPHS) and child health clinics (CHC), and a random sample of parents received an internet survey on varicella vaccination. Separate logistic regression models were used to identify determinants for a positive attitude (professionals) or a positive intention (parents) to vaccinate against varicella within the NIP (free of charge). RESULTS: The questionnaire was completed by 181 RPHS professionals (67 %), 260 CHC professionals (46 %), and 491 parents (33 %). Of professionals, 21 % had a positive attitude towards universal varicella vaccination, while 72 % preferred to limit vaccination to high-risk groups only. Of parents, 28 % had a positive intention to vaccinate their child against varicella within the NIP. The strongest determinant for a positive attitude or intention to vaccinate against varicella among professionals and parents was the belief that varicella is a disease serious enough to vaccinate against. CONCLUSIONS: We showed that a majority of the Dutch public health professionals and parents in this study have a negative attitude or low intention to vaccinate universally against varicella, as a result of the perceived low severity of the disease. Most participating professionals support selective vaccination to prevent varicella among high-risk groups

Large ongoing measles outbreak in a religious community in the Netherlands since May 2013

Contains fulltext : 126010.pdf (publisher's version ) (Open Access

Rabies risk behaviour in a cohort of Dutch travel clinic visitors: A retrospective analysis

BACKGROUND: Travellers to rabies endemic countries should be counselled on rabies risk and, in case of high-risk, pre-exposure vaccination is advised. However, it is not clear which travellers exactly are at high risk. In this study we determined the incidence of possible rabies exposure in travel clinic visitors and compliance with pre-travel advice. METHODS: Travellers to rabies endemic countries who visited a Dutch travel clinic between September 2017 and May 2018, were invited to participate. RESULTS: Of 980 travellers, one percent was injured by a potentially rabid animal. Compliance with advice was low as 59% reported proximity to a potentially rabid animal and only half of those exposed sought medical advice. The most important predictors of proximity to a potentially rabid animal were young age, long travel duration, visiting a monkey forest and hiking for more than one day. Travel for business was associated with lower risk. CONCLUSION: Despite pre-travel advice, rabies risk behaviour was high. Therefore, we would recommend to keep the threshold for pre-travel vaccination low. Pending more data on rabies exposure risk, the identified predictors of proximity to potentially rabid animals could be used to tailor indications for pre-travel rabies vaccination

Predictive Performance of Cardiovascular Disease Risk Prediction Algorithms in People Living With HIV

Immunogenetics and cellular immunology of bacterial infectious disease

High treatment uptake in human immunodeficiency virus/ hepatitis C virus-coinfected patients after unrestricted access to direct-acting antivirals in the Netherlands

Background The Netherlands has provided unrestricted access to direct-acting antivirals (DAAs) since November 2015. We analyzed the nationwide hepatitis C virus (HCV) treatment uptake among patients coinfected with human immunodeficiency virus (HIV) and HCV. Methods Data were obtained from the ATHENA HIV observational cohort in which >98% of HIV-infected patients ever registered since 1998 are included. Patients were included if they ever had 1 positive HCV RNA result, did not have spontaneous clearance, and were known to still be in care. Treatment uptake and outcome were assessed. When patients were treated more than once, data were included from only the most recent treatment episode. Data were updated until February 2017. In addition, each treatment center was queried in April 2017 for a data update on DAA treatment and achieved sustained virological response. Results Of 23574 HIV-infected patients ever linked to care, 1471 HCV-coinfected patients (69% men who have sex with men, 15% persons who [formerly] injected drugs, and 15% with another HIV transmission route) fulfilled the inclusion criteria. Of these, 87% (1284 of 1471) had ever initiated HCV treatment between 2000 and 2017, 76% (1124 of 1471) had their HCV infection cured; DAA treatment results were pending in 6% (92 of 1471). Among men who have sex with men, 83% (844 of 1022) had their HCV infection cured, and DAA treatment results were pending in 6% (66 of 1022). Overall, 187 patients had never initiated treatment, DAAs had failed in 14, and a pegylated interferon-alfa–based regimen had failed in 54. Conclusions Fifteen months after unrestricted DAA availability the majority of HIV/HCV-coinfected patients in the Netherlands have their HCV infection cured (76%) or are awaiting DAA treatment results (6%). This rapid treatment scale-up may contribute to future HCV elimination among these patients

Progression of liver fibrosis following acute hepatitis C virus infection in HIV-positive MSM

Molecular basis of virus replication, viral pathogenesis and antiviral strategie

A highly virulent variant of HIV-1 circulating in the Netherlands.

We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log <sub>10</sub> increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence