ABSTRACT
Sero-epidemiological surveys of serum samples taken in 1982, 1987, 1994 and 1999 have been performed with hepatitis A virus-specific (HAV-specific) serological tests. Results obtained during these surveys show that the proportion of seropositive blood donors decreased from 69% to 18% within 17 years. The authors have recognised a (mainly subclinical) epidemic, affecting about 115000 teenagers in 1992-1994 in Hungary, is a threatening phenomenon. It was calculated that only about 3600 clinical diseases were associated with the epidemic, recognised retrospectively from the findings of the four sero-epidemiological surveys. Epidemiological data indicated that the excess clinical diseases caused by HAV concentrated in the southern counties of Hungary, which have been affected by the social and military activities between 1992 and 1994. Due to the decrease of subjects seropositive for HAV, sera from preselected or actively immunised donors will be required in the future and vaccination against HAV with killed virus is likely to be recommended for risk groups. Furthermore, health authorities might promote active immunisation of young children against HAV infection; for that, promotion of manufacturing combination vaccines of HAV/HBV/DPT or, for certain countries, HAV/DPT would be desirable.
Subject(s)
Hepatitis A virus/isolation & purification , Hepatitis A/epidemiology , Seroepidemiologic Studies , Adolescent , Child , Cohort Studies , Disease Outbreaks , Hepatitis A/diagnosis , Hepatitis A/immunology , Hepatitis A/transmission , Hepatitis A virus/immunology , Hepatitis Antibodies/blood , Humans , Hungary/epidemiologyABSTRACT
INTRODUCTION: The authors present recent results in the Hungarian hantavirus ecology and epidemiology. Most of the research was done between 1992-2000. AIM: To determine the presence and geographic distribution of hantaviruses and to get more detailed information of human and small-mammal infection with these viruses in Hungary. METHODS: For diagnostic purposes (patients' sera), serosurvey of healthy persons and serological investigations of small mammals, the following tests were used: indirect fluorescent antibody, high density particle agglutination and enzyme-linked immunosorbent assay (ELISA). Virus isolation, antigen-, and nucleic acid detection were conducted for ecological investigations. RESULTS: 235 of 831 patients proved to be seropositive. 2257 sera of age matched Hungarian citizens above 20 years were tested in 2000. The average seropositivity proved to be about 10% using two different methods. Sera of 1512 individuals of nearly 20 different mammalian species were tested. Serological results revealed the prevalence of antibodies to human pathogen hantaviruses among rodents of about 7.25 percent. Molecular analysis of viral nucleic acid isolates from organs of four rodents proved directly the presence of viruses belonging to Puumala and Dobrava/Belgrade species in Hungary. Sequences corresponding to the Dobrava/Belgrade type viruses were found in two different rodent species. This suggests the existence of two hosts with different living preferences. CONCLUSIONS: At least two different human pathogen hantaviruses are circulating in Hungary. It has to be considered, that viruses belonging to the Dobrava/Belgrade species could emerge not only in the forested areas, but in the agricultural areas as well. Commercially available kits are not perfectly suitable for the detection of antibodies rised to domestic hantaviruses. It is necessary to built an appropriate laboratory for the hantavirus research in Hungary.
