Spillover of a hepatitis A outbreak among men who have sex with men (MSM) to the general population, the Netherlands, 2017.

Since 2015, outbreaks of hepatitis A among men who have sex with men (MSM) have been reported worldwide. To examine the impact of these MSM outbreaks in the Netherlands, we combined notification and epidemiological data with sequence analysis. Our results show the hazards of outbreaks within risk-groups spilling over into the largely susceptible general population. One third of the outbreak-related hepatitis A virus genotypes were detected in non-MSM cases

Seroprevalence of varicella-zoster virus and predictors for seronegativity in the Amsterdam adult population

Abstract Background In the Netherlands, infection with varicella-zoster virus (VZV) is considered a benign common childhood illness and routine vaccination against VZV is not done. In 1995 it was estimated that 98-100% of the adult Dutch general population is immune, yet the estimate is based on a database in which a relative small number of people of non-Dutch ethnic origin were represented. As the city of Amsterdam has large immigrant communities originating from various subtropical and tropical countries, such as Morocco, Surinam, and Turkey with probably lower VZV transmission, this study aimed to estimate the seroprevalence of VZV IgG antibodies (anti-VZV) among various ethnic groups in Amsterdam, and identify factors associated with seronegative VZV status. Methods The study was a cross-sectional survey of the Amsterdam population (2004), and the study sample was stratified by age and ethnicity, with deliberate oversampling of minority ethnic groups. Serum samples obtained from 1,341 residents in 2004 were tested for antibodies to VZV. Basic demographic data (gender, age, country of birth, age at immigration and number of children) were also available. Results The anti-VZV seroprevalence in the overall Amsterdam population was estimated to be 94% (95% confidence intervals; 92–96%). Regarding ethnic origin, first generation immigrants (Moroccan immigrants 90%, Surinamese or Antillean immigrants 91%, and Turkish 92%), especially those that migrated after the age of 11 years, were more likely to be anti-VZV seronegative compared to those arriving at an earlier age or those born in the Netherlands (97–98%). Both ethnic origin and generation of immigration were positive predictors for IgG seronegativity to VZV (p Conclusion The results of this study imply that about 4–8% of the general adult Amsterdam population is still susceptible to infection with VZV, and that susceptibility is even higher in some immigrant groups. When assessing the risk of infection after VZV exposure alertness is needed for vulnerable persons like pregnant women, patients with hematological malignancies or organ transplants in particular among first-generation immigrants.</p

Paediatric monkeypox patient with unknown source of infection, the Netherlands, June 2022.

Since May 2022, an international monkeypox (MPX) outbreak has been ongoing in more than 50 countries. While most cases are men who have sex with men, transmission is not restricted to this population. In this report, we describe the case of a male child younger than 10 years with MPX in the Netherlands. Despite thorough source tracing, a likely source of infection has not been identified. No secondary cases were identified in close contacts

Declining incidence of imported malaria in the Netherlands, 2000-2007

<p>Abstract</p> <p>Background</p> <p>To describe the epidemiology and trends of imported malaria in the Netherlands from 2000 through 2007.</p> <p>Methods</p> <p>Based on national surveillance data regarding all reported infections of imported malaria, diagnosed 2000 through 2007, incidence and trends of imported malaria in the Netherlands were estimated. Travellers statistics were used to estimate incidence, and data on malaria chemoprophylaxis prescriptions were used to estimate the number of unprotected travellers.</p> <p>Results</p> <p>Importation of malaria to the Netherlands is declining even as more travellers visit malaria-endemic countries. On average, 82% were acquired in sub-Saharan Africa, and 75% were caused by <it>Plasmodium falciparum</it>. The overall incidence in imported falciparum malaria fell from 21.5 to 6.6/10,000 of unprotected travellers. The percentage of unprotected travellers rose from 47% to 52% of all travellers. The incidence of imported falciparum infections is greatest from Middle and West Africa, and decreased from 121.3 to 36.5/10,000 travellers. The import of malaria from this region by immigrants visiting friends and relatives (VFR) decreased from 138 infections in 2000, to 69 infections in 2007.</p> <p>Conclusion</p> <p>The annual number of imported malaria shows a continuing declining trend, even with an increasing number of travellers visiting malaria endemic countries. VFR import less malaria than previously, and contribute largely to the declining incidence seen. The decline is not readily explained by increased use of chemoprophylaxis and may reflect a reduced risk of infection due to decreasing local malaria transmission as observed in some malaria endemic areas. Nevertheless, the increasing number of unprotected travellers remains worrisome.</p