Neuropediatrics 2007; 38(6): 292-297
DOI: 10.1055/s-2008-1065357
Original Article

© Georg Thieme Verlag KG Stuttgart · New York

Confirmed Primary HHV-6 Infection in Children with Suspected Encephalitis

J. O. Virtanen 1 , 2 , E. Herrgård 3 , P. Valmari 4 , J. Ahlqvist 5 , A. Fogdell-Hahn 5 , A. Vaheri 1 , 2 , M. Koskiniemi 1
  • 1Department of Virology, Haartman Institute, University of Helsinki, Helsinki, Finland
  • 2Department of Virology, HUSLAB-Laboratory Services, Helsinki, Finland
  • 3University Hospital of Kuopio, Kuopio, Finland
  • 4Central Hospital of Lapland, Rovaniemi, Finland
  • 5Department of Clinical Neuroscience, Division of Neurology, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden
Weitere Informationen


received 31.08.2007

accepted 26.02.2008

06. Mai 2008 (online)


HHV-6 infection has been associated with neurological symptoms in children. Two variants of human herpes virus 6, HHV-6A and HHV-6B, have been identified. Their role in neurological infections is poorly understood. We studied 53 children with suspected encephalitis for HHV-6A (strain GS) and HHV-6B (strain Z29) antibodies using an indirect immunofluorescence test. Primary infection was separated from past infection by an IgG-avidity test. The identified primary infections were studied for HHV-6 specific DNA by PCR. Forty-one children of 53 had IgG antibodies to HHV-6. Six children had low avidity of HHV-6 IgG antibodies indicating acute primary infection; four to type A, one to B, and one to both types. By serology, HHV-6 viral etiology was suggested in 6/53 (11.3%) of cases. One of the six patients with primary infection had HHV-6 DNA in serum and two in CSF. The children with primary HHV-6 infection were significantly younger than the whole series, 2.3 years vs. 6.4 years. We conclude that primary HHV-6 infection appears to be an important associated or causative agent in neurological infections of young children, and it can be confirmed from a single serum specimen using the IgG-avidity test.



J. O. Virtanen

Department of Virology

Haartman Institute

University of Helsinki

Haartmaninkatu 3

P.O.Box 21

00014 Helsinki


Telefon: +358/9/1912 64 65

Fax: +358/9/1912 64 91

eMail: [email protected]