Supplement bij veertiende jaargang, april 2006 - NVMM

De eerste twee studies concluderen, nogal somber,
respectievelijk:
1) The analysis indicates that the Dutch prevention strategy
fails to stop transmission of hepatitis B from persistently
infected individuals originating from hepatitis B endemic
countries. 2) It must be realised that, after 20 years of
vaccination of at-risk groups, HBV still circulates in the
at-risk groups and Dutch blood donors acquire the HBV
strains involved.
Kan de vorderende, landelijke typering van acute HBVisolaten
[3] nuttig licht op deze zaak werpen? Of is deze
exercitie symptomatisch voor een steeds ingewikkelder,
mogelijk inefficiënt risicogroepenbeleid?
References
1. Steenbergen JE van, Niesters HG, et al. Molecular epidemiology
of hepatitis B virus in Amsterdam 1992-1997. J
Med Virol 2002;66:159-65.
2. Koppelman MH, Zaaijer HL. Diversity and origin of
hepatitis B virus in Dutch blood donors. J Med Virol
2004;73:29-32.
3. Boot H. Workshop moleculaire typering HBV in
Nederland: inzicht in transmissie en epidemiologie van
HBV. Infectieziektenbulletin 2005;16:280-1.
09.02
Tracking hepatitis A virus within and among risk groups
S.M. Bruisten1 , G.M.S. Tjon1 , R.A. Coutinho2 1GGD, Public Health laboratory, Department of Infectious
Diseases, Amsterdam, 2Centre for Infectious Diseases, RIVM,
Bilthoven
In the Netherlands the incidence of infection with hepatitis
A virus (HAV) is decreasing due to high hygienic standards
and vaccination of targeted risk groups. As a consequence
the susceptibility to HAV is increasing with a potential
of larger outbreaks and higher morbidity among adults.
In Amsterdam, we identified an association of groups at
risk for HAV infection and (sub)genotypes of the virus.
Travel to Morocco resulted mainly in infections of the
1B genotype, whereas among men having sex with men
(MSM) exclusively genotype 1A was found.[1] During four
years, with the cooperation of 8 GGDs, we established a
national HAV database containing epidemiological data
combined with phylogenetic analysis. It reinforced our
findings that the correlation risk to genotype was valid all
over the Netherlands.[2,3] Moreover, in other European
countries the same MSM strains were identified during
outbreaks, suggesting endemic transmission among MSM.
Travel associated introductions generally appeared in
small clusters, disappearing soon after introduction.
This suggests that travel related HAV introductions are
effectively recognized and stopped.
Ned Tijdschr Med Microbiol 2006; 4:Supplement
S4
Among drug users a major outbreak occurred in Rotterdam
in spring 2004. With molecular epidemiology all cases
with the genotype 3A outbreak strain could be distinguished
from sporadic cases with other genotypes. This
was helpful to assess the efficacy of the mass vaccination
campaign.[4] For public health purposes it is of major
importance to know the period of infectivity. We therefore
followed 27 acute HAV patients for 26 weeks, measuring
viral load in blood and faeces. We found a significant
correlation of HAV and ALT levels in serum. However,
the acute load in faeces was not related to genotype, nor to
duration of excretion. High loads in faeces were found for
81 days, suggesting that transmission may still occur when
adhering to the current policy of 2 weeks of infectiousness
after symptoms.
HAV typing is of use to aid establishig epidemiological
links. Thus the national HAV database should be kept
updated.
References
1. Bruisten SM, et al. JMV 2001;63:88.
2. Steenbergen JE van, et al. JID 2004;189:471.
3. Tjon GMS, et al. JCV 2005;32:128
4. Tjon GMS, et al. JMV 2005;77:360.
09.03
Moleculaire epidemiologie en tuberculosebestrijding, toy
and tool
M. Šebek
KNCV Tuberculosefonds, Den Haag
Achtergrond: In 1994 ging de Mycobacterium tuberculosis
DNA en resistentiesurveillance van start, een co-project
van KNCV Tuberculosefonds en het Rijksinstituut voor
Volksgezondheid en Milieu (RIVM) in samenwerking met
de GGD’en. Het doel is de transmissie van de M. tuberculosis-stammen
in kaart te brengen en daarmee inzicht te
krijgen in de verspreiding van de verschillende stammen
onder de bevolkingsgroepen in Nederland; het traceren
van bronnen en hun contacten en van onvermoede latente
tuberculoseinfecties (LTBI).
Methode: Nadat op het RIVM onderscheid is gemaakt
tussen materiaal van patiënten met een uniek (d.w.z.
niet eerder gevonden) DNA-fingerprintpatroon en 100%
identieke patronen (de zogenaamde clusters), meldt de
verpleegkundig consulent surveillance de geclusterde
patiënten aan de afdeling tuberculosebestrijding van
de GGD’en. De sociaalverpleegkundigen trachten
vervolgens epidemiologische verbanden aan te tonen
samen met de sociaalverpleegkundigen van GGD’en
waar andere patiënten in de clusters zijn gevonden aan
de hand van de sociale anamnese van de patiënt(en).
Over iedere geclusterde patiënt worden de bevindingen