G J B Sonder

Publications (9)15.05 Total impact

• Article: [West Nile virus expanding in Europe].

  Chantal B E M Reusken, C Kees van Maanen, Byron E Martina, Gerard J B Sonder, Eric C M van Gorp, Marion P G Koopmans
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  ABSTRACT: The areas of Europe in which West Nile virus (WNV)-transmission to humans is observed have expanded over the last few years, with endemic circulation amongst animals of southern Europe. This situation calls for heightened vigilance to the clinical presentation of WNV infection in humans. The average incubation period lasts 2-6 days. Of those infected, 20% will experience a mild, non-specific disease presentation such as high fever, headache, myalgia, possibly with rash and lymphadenopathy; <1% will develop severe neurological symptoms. Rare complications include: myelitis, optic neuritis, rhombencephalitis, polyradiculitis, myocarditis, pancreatitis and fulminant hepatitis. Clinicians should take WNV infection into consideration when making a differential diagnosis for such symptoms in patients who have returned from areas with potential virus circulation. Given the increase in the spread of WNV within Europe, this now holds true for continental travellers as well as those destined for the Americas, Africa and Asia. It is important to include the patient's travel history, clinical symptoms and any occurrences of vaccination against viruses causing Japanese encephalitis, tick-borne encephalitis and yellow fever into the diagnostic workup, as the antibodies against these diseases show cross-reactivity.
  Nederlands tijdschrift voor geneeskunde 01/2011; 155(39):A3715.
• Article: Population-based study on the seroprevalence of parvovirus B19 in Amsterdam.

  G G C van Rijckevorsel, G J B Sonder, M F Schim van der Loeff, J A R van den Hoek
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  ABSTRACT: A study was undertaken to estimate the seroprevalence of parvovirus B19 infection in the general adult population of Amsterdam, The Netherlands. To our knowledge this is the first study testing parvovirus B19 in a random sample of the Dutch adult population. The study was a cross-sectional survey, and the study sample was stratified by age and ethnicity, with deliberate oversampling of minority ethnic groups. Serum samples obtained from 1,323 residents in 2004 were tested for antibodies to parvovirus B19. Basic demographic data (gender, age, country of birth, and number of children) were also available. Sixty-two percent of the participants were seropositive; corrected for the oversampling the estimated prevalence in the Amsterdam adult population was 61%. No specific predictors or risk groups for seropositivity were identified. In our urban adult study population no positive correlation with increasing neither age, nor significant differences between age groups were found. These results imply that almost 40% of the adult Amsterdam population is susceptible to infection. J. Med. Virol. 81:1305-1309, 2009. (c) 2009 Wiley-Liss, Inc.
  Journal of Medical Virology 08/2009; 81(7):1305-9. · 2.82 Impact Factor
• Article: Population‐based study on the seroprevalence of parvovirus B19 in Amsterdam

  G.G.C. van Rijckevorsel, G.J.B. Sonder, M.F. Schim van der Loeff, J.A.R. van den Hoek
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  ABSTRACT: A study was undertaken to estimate the seroprevalence of parvovirus B19 infection in the general adult population of Amsterdam, The Netherlands. To our knowledge this is the first study testing parvovirus B19 in a random sample of the Dutch adult population. The study was a cross-sectional survey, and the study sample was stratified by age and ethnicity, with deliberate oversampling of minority ethnic groups. Serum samples obtained from 1,323 residents in 2004 were tested for antibodies to parvovirus B19. Basic demographic data (gender, age, country of birth, and number of children) were also available. Sixty-two percent of the participants were seropositive; corrected for the oversampling the estimated prevalence in the Amsterdam adult population was 61%. No specific predictors or risk groups for seropositivity were identified. In our urban adult study population no positive correlation with increasing neither age, nor significant differences between age groups were found. These results imply that almost 40% of the adult Amsterdam population is susceptible to infection. J. Med. Virol. 81:1305–1309, 2009. © 2009 Wiley-Liss, Inc.
  Journal of Medical Virology 06/2009; 81(7):1305 - 1309. · 2.82 Impact Factor
• Article: [Hepatitis B and C].

  G J B Sonder, J A R van den Hoek
  Nederlands tijdschrift voor geneeskunde 01/2008; 151(50):2809; author reply 2809-10.
• Source

  Available from: uva.nl

  Article: Population-based study on the seroprevalence of hepatitis A, B, and C virus infection in Amsterdam, 2004.

  G G G Baaten, G J B Sonder, N H T M Dukers, R A Coutinho, J A R Van den Hoek
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  ABSTRACT: In order to enhance screening and preventive strategies, this study investigated the seroprevalence of hepatitis A, B, and C in the general adult urban population and in subgroups. In 2004, sera from 1,364 adult residents of Amsterdam were tested for viral markers. Sociodemographic characteristics were collected using a standardized questionnaire. For hepatitis A, 57.0% was immune. Of first-generation immigrants from Turkey and Morocco, 100% was immune. Of all Western persons and second-generation non-Western immigrants, approximately half was still susceptible. For hepatitis B, 9.9% had antibodies to hepatitis B core antigen (anti-HBc) and 0.4% had hepatitis B surface antigen. Anti-HBc seroprevalences were highest among first-generation immigrants from Surinam, Morocco, and Turkey, and correlated with age at the time of immigration, and among men with a sexual preference for men. Seroprevalence among second-generation immigrants was comparable to Western persons. The seroprevalence of hepatitis C virus antibodies was 0.6%. In conclusion, a country with overall low endemicity for viral hepatitis can show higher endemicity in urban regions, indicating the need for differentiated regional studies and prevention strategies. More prevention efforts in cities like Amsterdam are warranted, particularly for hepatitis A and B among second-generation immigrants, for hepatitis B among men with a sexual preference for men, and for hepatitis C. Active case finding strategies are needed for both hepatitis B and C.
  Journal of Medical Virology 01/2008; 79(12):1802-10. · 2.82 Impact Factor
• Article: Population‐based study on the seroprevalence of hepatitis A, B, and C virus infection in Amsterdam, 2004

  G.G.G. Baaten, G.J.B. Sonder, N.H.T.M. Dukers, R.A. Coutinho, J.A.R. Van den Hoek
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  ABSTRACT: In order to enhance screening and preventive strategies, this study investigated the seroprevalence of hepatitis A, B, and C in the general adult urban population and in subgroups. In 2004, sera from 1,364 adult residents of Amsterdam were tested for viral markers. Sociodemographic characteristics were collected using a standardized questionnaire. For hepatitis A, 57.0% was immune. Of first-generation immigrants from Turkey and Morocco, 100% was immune. Of all Western persons and second-generation non-Western immigrants, approximately half was still susceptible. For hepatitis B, 9.9% had antibodies to hepatitis B core antigen (anti-HBc) and 0.4% had hepatitis B surface antigen. Anti-HBc seroprevalences were highest among first-generation immigrants from Surinam, Morocco, and Turkey, and correlated with age at the time of immigration, and among men with a sexual preference for men. Seroprevalence among second-generation immigrants was comparable to Western persons. The seroprevalence of hepatitis C virus antibodies was 0.6%. In conclusion, a country with overall low endemicity for viral hepatitis can show higher endemicity in urban regions, indicating the need for differentiated regional studies and prevention strategies. More prevention efforts in cities like Amsterdam are warranted, particularly for hepatitis A and B among second-generation immigrants, for hepatitis B among men with a sexual preference for men, and for hepatitis C. Active case finding strategies are needed for both hepatitis B and C. J. Med. Virol. 79:1802–1810, 2007. © Wiley-Liss, Inc.
  Journal of Medical Virology 10/2007; 79(12):1802 - 1810. · 2.82 Impact Factor
• Article: Effectiveness of a hepatitis A vaccination program for migrant children in Amsterdam, The Netherlands (1992-2004).

  G J B Sonder, L P M J Bovée, T D Baayen, R A Coutinho, J A R van den Hoek
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  ABSTRACT: To evaluate the impact and effectiveness of risk-group vaccination against hepatitis A targeted at migrant children living in a country with low endemicity of hepatitis A. Retrospective population based data analysis. Routinely collected data on hepatitis A incidence in migrant children and other risk groups in Amsterdam from 1 January 1992 to 2004 were analyzed and related to exposure, immunity and vaccination coverage in migrant children. The overall hepatitis A incidence in Amsterdam declined after a pediatric vaccine was introduced in 1997. This decline was seen in migrant children traveling to hepatitis A-endemic countries, contacts with hepatitis A patients, primary school students, injecting drug users, and persons with unknown source of infection, but not in men who have sex with men (MSM) or in travelers to endemic countries other than migrant children. The hepatitis A vaccination campaigns are effective: they reduce both import and secondary HAV cases. The campaigns could be more efficient and cost-effective if the hepatitis B vaccinations currently given to these groups were replaced by a combined hepatitis A and B vaccine. This would increase the hepatitis A vaccination coverage considerably and further reduce the hepatitis A incidence.
  Vaccine 07/2006; 24(23):4962-8. · 3.77 Impact Factor
• Article: [Post-exposure treatment against HIV outside of the hospital in Amsterdam, January-December 2000].

  G J B Sonder, R M Regez, K Brinkman, J M Prins, J W Mulder, R A Coutinho, J A R van den Hoek
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  ABSTRACT: The Infectious Diseases Department of the Amsterdam Public Health Service regularly sees people who have possibly been exposed to human body fluids infected with hepatitis B virus (HBV), hepatitis C virus (HCV) or human immunodeficiency virus (HIV), as a result of incidents in either a non-hospital-related occupation or during their leisure time. Until January 2000, people reporting possible exposure were referred to hospitals for HIV post-exposure prophylaxis (HIV-PEP), whereas for HBV and HCV, the tracing of the infection source and the follow-up took place at the Public Health Service clinic. Since the introduction of a new protocol in January 2000, the Public Health Service as well as a hospital can establish an indication for HIV-PEP and prescribe it. In 2000, 322 persons reported to the Public Health Service. The source was tested in 194 incidents and an HIV test was carried out on 104 occasions. In 19 cases HIV antibodies were found or the source was known to be HIV positive. A total of 50 people were prescribed HIV-PEP; 16 times after a needle-stick accident, 22 times after a sexual accident, 6 times after a bite-wound and 6 times after direct exposure to human blood. The sources of 30 PEP recipients could be tested and after this 16 recipients could stop with the treatment due to a negative HIV test. In 4 cases PEP treatment was stopped following a review of the indication. Therefore, 30 people had an indication to complete the PEP treatment. Of these, more than 80% reported side effects and 3 people had to withdraw from the treatment at an early stage because of this. The implementation of the protocol has resulted in less confusion because the follow-up now takes place at one location. Compared to other studies, the average time between exposure and treatment is shorter and compliance is good. In the period up to 15 May 2001, no seroconversions had been observed.
  Nederlands tijdschrift voor geneeskunde 04/2002; 146(13):629-33.
• Article: Effectiveness of a hepatitis A vaccination program for migrant children in Amsterdam, The Netherlands (1992–2004)

  G.J.B. Sonder, L.P.M.J. Bovée, T.D. Baayen, R.A. Coutinho, J.A.R. van den Hoek
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  ABSTRACT: ObjectiveTo evaluate the impact and effectiveness of risk-group vaccination against hepatitis A targeted at migrant children living in a country with low endemicity of hepatitis A.MethodsRetrospective population based data analysis. Routinely collected data on hepatitis A incidence in migrant children and other risk groups in Amsterdam from 1 January 1992 to 2004 were analyzed and related to exposure, immunity and vaccination coverage in migrant children.ResultsThe overall hepatitis A incidence in Amsterdam declined after a pediatric vaccine was introduced in 1997. This decline was seen in migrant children traveling to hepatitis A-endemic countries, contacts with hepatitis A patients, primary school students, injecting drug users, and persons with unknown source of infection, but not in men who have sex with men (MSM) or in travelers to endemic countries other than migrant children.ConclusionThe hepatitis A vaccination campaigns are effective: they reduce both import and secondary HAV cases. The campaigns could be more efficient and cost-effective if the hepatitis B vaccinations currently given to these groups were replaced by a combined hepatitis A and B vaccine. This would increase the hepatitis A vaccination coverage considerably and further reduce the hepatitis A incidence.
  Vaccine.