Detection of enteric viruses in Hungarian surface waters: first steps towards environmental surveillance.

Waterborne viruses infect the human population through the consumption of contaminated drinking water and by direct contact with polluted surface water during recreational activity. Although water related viral outbreaks are a major public health concern, virus detection is not a part of the water quality monitoring scheme, mainly due to the absence of routine analysis methods. In the present study, we implemented various approaches for water concentration and virus detection, and tested on Hungarian surface water samples. Eighty samples were collected from 16 sites in Hungary. Samples were concentrated by glass wool and membrane filtration. Human adenoviruses were detected by conventional and quantitative real-time polymerase chain reaction (PCR) methods in 56% (45/80) of the samples; viral titers ranged from 8.60 × 10(1) to 3.91 × 10(4) genome copies per liter. Noroviruses and enteroviruses were detected in 30% (24/80) and 13% (10/80) of samples, respectively, by reverse transcription-PCR assays. Results indicate a high prevalence of viral human pathogens in surface waters, suggesting the necessity of a detailed survey focusing on the quality of natural bathing waters and drinking water sources.

Experimental infection of goats with tick-borne encephalitis virus and the possibilities to prevent virus transmission by raw goat milk.

OBJECTIVES: The aim of this work was to study the tick-borne encephalitis virus (TBEV) infection of goats and the possibilities to prevent human milk-borne infections either by immunizing animals or the heat treatment of milk. METHODS: An experiment was conducted with 20 milking goats. Ten goats (half of them immunized) were challenged with live TBEV and 10 were left uninfected. Clinical signs and body temperatures of the animals were recorded and milk samples were collected daily. The presence of viral RNA and infectious virions in milk were detected by RT-PCR and intracerebral inoculation of suckling mice, respectively. Milk samples containing infectious virions were subjected to various heat treatment conditions and retested afterwards to assess the effect on infectivity. RESULTS: The infected goats did not show any clinical signs or fever compared to uninfected ones. Infectious virions were detected for 8-19 days from the milk samples (genome for 3-18 days by PCR) of infected goats. Immunized goats did not shed the virus. After heat treatment of the milk, the inoculated mice survived. CONCLUSIONS: Goats shed the virus with their milk without showing any symptoms. Human milk-borne infections can be avoided both by immunizing goats and boiling/pasteurizing infected milk.

Paralytic poliomyelitis associated with Sabin monovalent and bivalent oral polio vaccines in Hungary.

Historical records of patients with vaccine-associated paralytic poliomyelitis (VAPP) in Hungary during 1961-1981 were reviewed to assess the risk of VAPP after oral polio vaccine (OPV) administration. A confirmed VAPP case was defined as a diagnosis of paralytic poliomyelitis and residual paralysis at 60 days in a patient with an epidemiologic link to the vaccine. Archived poliovirus isolates were retested using polymerase chain reaction and sequencing of the viral protein 1 capsid region. This review confirmed 46 of 47 cases previously reported as VAPP. Three cases originally linked to monovalent OPV (mOPV) 3 and one case linked to mOPV1 presented after administration of bivalent OPV 1 + 3 (bOPV). The adjusted VAPP risk per million doses administered was 0.18 for mOPV1 (2 cases/11.13 million doses), 2.96 for mOPV3 (32 cases/10.81 million doses), and 12.82 for bOPV (5 cases/390,000 doses). Absence of protection from immunization with inactivated poliovirus vaccine or exposure to OPV virus from routine immunization and recent injections could explain the higher relative risk of VAPP in Hungarian children. In polio-endemic areas in which mOPV3 and bOPV are needed to achieve eradication, the higher risk of VAPP would be offset by the high risk of paralysis due to wild poliovirus and higher per-dose efficacy of mOPV3 and bOPV compared with trivalent OPV.

Detection of non-polio enteroviruses in Hungary 2000-2008 and molecular epidemiology of enterovirus 71, coxsackievirus A16, and echovirus 30.

Human enteroviruses are associated with various clinical syndromes from minor febrile illness to severe, potentially fatal conditions like aseptic meningitis, paralysis, myocarditis, and neonatal enteroviral sepsis. Between June 2000 and August 2008 echovirus (E) type 2, 4, 6, 7, 9, 11, 13, 25, 30, coxsackievirus (CV) -A16, -A19, -B5, and enterovirus 71 (EV71) were reported in Hungary. In this study, 29 previously enterovirus positive samples from 28 patients diagnosed with hand, foot and mouth disease, meningitis and encephalitis, were molecularly typed. The genetic relationships of identified serotypes CV-A16, EV71, and E30 were assessed by direct sequencing of genomic region encoding the capsid protein VP1. The sequences were compared to each other and sequences from other geographical regions possessed in Genbank. The phylogenetic analysis of CV-A16 revealed that the viruses were mostly of Far-Eastern or Asia-Pacific origin. Typing of EV71 showed that one virus from 2000 belonged to genotype C1 and five viruses observed in 2004 and 2005 were identified as genotype C4. The 11 echovirus 30 strains showed homology with those of neighbor European countries. The molecular examination of E30 revealed that three separate lineages circulated in 2000, 2001, and 2004-2006 in Hungary.

Molecular characterization of poliovirus isolates from children who contracted vaccine-associated paralytic poliomyelitis (VAPP) following administration of monovalent type 3 oral poliovirus vaccine in the 1960s in Hungary.

Hungarian children were immunized with monovalent oral poliovaccine (mOPV) delivered at 6-week intervals in the order Sabin 1, Sabin 3, Sabin 2, from 1959 until 1992. During that period, 90 cases of vaccine-associated paralytic poliomyelitis (VAPP) were reported, 52 of which were associated with Sabin 3-related virus (76% of VAPP cases with virologic data). Because of renewed interest in type 3 mOPV (mOPV3), molecular methods were used to reanalyze 18 of the Sabin 3-related isolates from 15 VAPP patients, confirming the original identification. All isolates had the U472C 5'-untranslated region (5'-UTR) substitution associated with reversion to neurovirulence, and from zero to seven nucleotide substitutions in the virus protein 1 (VP1) region. No evidence was found for prolonged mOPV3 replication in the VAPP patients or for spread of Sabin 3-related viruses beyond close vaccinee contacts. The VAPP diseases were prevented by a single dose of inactivated poliovirus vaccine from 1992 to 2006 in Hungary, as proved by continuous surveillance of acute flaccid paralysis.

Tick-borne encephalitis outbreak in Hungary due to consumption of raw goat milk.

A tick-borne encephalitis outbreak involving 25 patients of 154 exposed persons occurred in Hungary in August 2007. None of the patients had a history of tick-bite, however all of them drank unpasteurized raw goat milk from the same farm. The aim of this study was to identify the goats on the farm which could have spread the infection through their milk. Blood samples were taken from 75 goats on the farm and were examined by various serological methods, namely indirect immunofluorescent assay, hemagglutination inhibition, microneutralization and an ELISA adapted to testing material from goats, to determine antibody levels in the serum. The four methods have proved different levels of specificity. The least specific was the indirect immunofluorescent assay, which showed a low titre in all sera. Comparison of the results of the other three methods indicates that two sera were positive for anti-TBEV IgG and one for anti-TBEV IgM. The goat with the IgM positive serum sample could have been a source of the infected milk. It has been concluded that serological results for goats by the different methods should be compared before final diagnosis because the specificity of methods in use can differ significantly.

Multicentric plasmocytic Castleman's disease with polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes syndrome and coexistent human herpes virus-6 infection--a possible relationship.

Authors report a case of Castleman's disease (CD) with polyneuropathy, organomegaly, endocrinopathy, M protein, skin change (POEMS) syndrome. According to the present knowledge, these two rare conditions are often induced by Human Herpes Vírus- 8 (HHV-8) or by Human Immunodefeciency Virus, separately or in combination. In this case, however, HHV-6 viral DNA had been detected in the blood and lymph node samples by PCR. The authors conclude that the modulation of immune functions by HHV-6 might be responsible for the development of CD and POEMS syndrome in the referred case.

Heterogeneous pathways of maternal-fetal transmission of human viruses (review).

Several viruses can pass the maternal-fetal barrier, and cause diseases of the fetus or the newborn. Recently, however, it became obvious, that viruses may invade fetal cells and organs through different routes without acute consequences. Spermatozoa, seminal fluid and lymphocytes in the sperm may transfer viruses into the human zygotes. Viruses were shown to be integrated into human chromosomes and transferred into fetal tissues. The regular maternal-fetal transport of maternal cells has also been discovered. This transport might implicate that lymphotropic viruses can be released into the fetal organs following cellular invasion. It has been shown that many viruses may replicate in human trophoblasts and syncytiotrophoblast cells thus passing the barrier of the maternal-fetal interface. The transport of viral immunocomplexes had also been suggested, and the possibility has been put forward that even anti-idiotypes mimicking viral epitopes might be transferred by natural mechanisms into the fetal plasma, in spite of the selective mechanisms of apical to basolateral transcytosis in syncytiotrophoblast and basolateral to apical transcytosis in fetal capillary endothelium. The mechanisms of maternal-fetal transcytosis seem to be different of those observed in differentiated cells and tissue cultures. Membrane fusion and lipid rafts of high cholesterol content are probably the main requirements of fetal transcytosis. The long term presence of viruses in fetal tissues and their interactions with the fetal immune system might result in post partum consequences as far as increased risk of the development of malignancies and chronic pathologic conditions are discussed.

Detection of human bocavirus from fecal samples of Hungarian children with acute gastroenteritis.

OBJECTIVES: Human bocavirus (HBoV), a newly identified member of the Parvoviridae family is associated with respiratory tract and gastroenteric infections, mostly of young children. HBoV infections show a seasonal distribution with the peak in temperate areas being in the winter months. METHODS: In our study, 35 throat swabs from children under 5 years with acute respiratory symptoms and 61 stool samples from children (<5 years) with acute gastroenteritis were collected in the period of October 2007-March 2008. A HBoV-specific polymerase chain reaction for detection of the virus, and sequence analysis for identification of virus variants were performed. RESULTS: Although respiratory samples were all negative, 3.3% of stool samples (2/61) proved to be positive for HBoV. The virus carrier children were 3 and 5 years old. The ratio of HBoV positive samples is similar to international results (2.1-5.5%). CONCLUSIONS: According to the result of sequence analysis of HBoV, the occurrence of genotype 2 of HBoV in Hungary is confirmed.

Severe tick-borne encephalitis in a patient previously infected by West Nile virus.

We describe severe tick-borne encephalitis (TBE) in a patient who had previously experienced West Nile fever, another flavivirus infection endemic in Hungary. Previous West Nile virus infection does not develop immunity either against TBE virus infection or the disease, and it does not mitigate its clinical course. The possibility of antibody-dependent enhancement is considered.

Mutation spectra of the surface-protein-coding region of the HBV genome in HBV-vaccinated and non-vaccinated individuals in Hungary.

Hepatitis B virus (HBV) infection has a major effect on health care systems, with about one-third of the world's population currently infected with the virus. There is an effective vaccine against HBV, which contains a recombinant "surface antigen" produced in an expression vector. Vaccination has proved to be successful in Hungary: the number of acute HBV cases has decreased in the past 10 years. Although an increasing number of publications report on "vaccine-escape" HBV variants which can infect HBV-vaccinated individuals, such mutant HBV strains have not yet been detected in Hungary. We therefore surveyed two risk groups for vaccine-escape or immunoglobulin-escape HBV mutations in Hungary: 28 actively and/or passively HBV-immunized children of HBV carrier mothers who proved to be HBsAg and/or anti-HBc positive and 40 symptomless HBV carrier pregnant women (presumably carrying genotype B or C). We focused on the coding sequences of the "a" immundominant region of the surface protein. We could not detect the G145R amino acid substitution associated with vaccine escape mutant virus. However, we could map other mutations potentially affecting the immunodominant "a" region of the HBV surface protein.

Persistent long-term human herpesvirus 6 (HHV-6) infection in a patient with langerhans cell histiocytosis.

Langerhans cell histiocytosis (eosinophilic granuloma) was first diagnosed in the adolescence of a male patient presented. Several years later persisting human herpesvirus 6 (HHV-6) infection was recognized. The HHV-6 infection could be verified retrospectively in his historical histological samples; the continuous presence of HHV-6 could be established through 17 years of disease course. The patient was operated several times during this period for painful relapses, and developed diabetes insipidus. At variable time points during the clinical course, Varicella zoster (VZV), Epstein-Barr virus (EBV) and human herpesvirus 8 (HHV-8) infections were temporarily detected from blood samples and biopsy specimens. HHV-6 was the only virus continuously identified throughout the entire follow-up period. Antiviral therapy effectively cleared EBV and HHV-8, but HHV-6 remained detectable throughout the disease course. Since DNA sequences of HHV-6 could be detected in the pathologic histiocytes of eosinophilic granuloma, and from other samples taken later on, it is suggested that long-term HHV-6 infection may be associated with development or progression of Langerhans cell histiocytosis.

Detection of four lymphotropic herpesviruses in Hungarian patients with multiple myeloma and lymphoma.

It has been suggested that human herpesvirus 8 (HHV-8), also known as KSHV (Kaposi's sarcoma-associated human herpesvirus), might possess a promoting effect in the development and progression of monoclonal gammopathies. In this study, the presence of Epstein-Barr virus (EBV), human cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and human herpesvirus 8 (HHV-8) were tested in patients with multiple myeloma (MM) using both serologic and nucleic acid amplification techniques. The transient reactivation or continuous presence of EBV, CMV, HHV-6 and HHV-8 could be detected in, respectively, 36, eight, 13 and 29 of 69 MM patients; nine, one, four and six of 16 monoclonal gammopathy of unknown significance patients; and seven, four, zero and five of 10 Waldenström's macroglobulinemia patients. The total number of MM patients was 95. HHV-8 PCR-positivity was significantly more frequent in the MM group than in the control group of patients with non-Hodgkin's lymphoma (NHL). However, serologic testing did not reveal significant differences between the two patient groups. The number of MM patients with concomitant herpesvirus infections as detected by PCR was as follows: 15 double, seven triple and two quadruple virus nucleic acid positive. In 13/95 MM patients, the simultaneous presence of acute EBV infection and HHV-8 PCR-positivity was detected compared with none of the control group (P=0.009). These results indicate that in addition to HHV-8, the transitional reactivation of EBV may also play a role in the pathogenesis of MM.

A simple spatial model to explain the distribution of human tick-borne encephalitis cases in hungary.

Tick-borne encephalitis (TBE) is a common medical problem in Hungary and throughout much of Europe and Asia. This paper develops a geographic model that helps to predict the distribution of human tick-borne encephalitis cases in Hungary. The model is tested on a dataset of serologically confirmed TBE cases mapped by patients' residences. Case densities (incidence rates) are compared to predicted distributions of TBE derived from digital land-cover data. Maps are analyzed at the county level and on a smaller spatial scale. The analyses identified three major factors that shape the geographic distribution of human TBE cases in Hungary. The most important component is the distribution of forest habitat. TBE incidence correlates positively with the amount of forested habitat in each county. On a finer scale, the amount of forests within a 2500-meter radius of each town and village correlated significantly with TBE incidence rate. Based on these data, about 30% of the variation in TBE incidence is accounted for by the specific distribution of forest habitats in Hungary. Besides the distribution of forests, differences in human land-use practices among regions also affect the distribution of TBE cases. Additionally, because of the low transmission rate of the virus to humans, the perceived distribution of TBE cases is affected by random stochastic events. As a consequence of stochastic variation, meaningful patterns in the distribution of TBE cases can be only recognized when data are analyzed over broader temporal and spatial scales.

[Prevention of malignant tumors caused by human papilloma virus (HPV) by vaccination and with the methods of classical gynecologic diagnostics]. / A humán papillomavírus (HPV) okozta rosszindulatú daganatok megelozése védooltással es a klasszikus nogyógyászati diagnosztika módszereivel.

The "gold standard" of the gynecologic examinations is even today the classical clinical examination completed with the digital colposcopy, the Pap smears prepared from transport media and histological examination of biopsy material. Without these classical examinations one cannot evaluate the results of the molecular tests detecting papillomaviruses. The majority (70 to 90%) of the primary clinical symptoms caused by papillomaviruses recovers spontaneously. The recovery can be supported by, "imiquimod" (Aldara) which is an immunostimulant-inducing interferon gamma and the production of interleukins, since papillomavirus infection is able to prevent the production of these mediators through its blocking effect to the innate immunity. Prevention is the main aim of the contemporary public health facilitated by the modern gene technology. The tetravalent vaccine (types 6, 11, 16 and 18) is harmless, since no tumor inducing genes are included. The empty capsids are manufactured in yeast cells and purified to a high degree similar to that of hepatitis B vaccine. The tetravalent vaccine is a preventive vaccine. It will be useful for teenagers, who have not acquired yet the most common papillomavirus types. There is intensive research going on in order to create therapeutic vaccines, that might be effective also in people of older age who had acquired certain virus types before vaccination, and may possess clinical symptoms, too. Men are the source of papillomavirus infection of women. Therefore vaccination of both genders will be indicated. The importance of the classical diagnostic procedures will not be diminished even under the umbrella of vaccination, since the preventive efforts were shown to be fully effective, if the clinical examinations, colposcopy, pap smears and biopsies are regularly performed in the patients with clinical symptoms increasing the rate of recovery above 90%. About 13 to 15 subtypes of human papillomaviruses may induce malignant processes. These are also present and most frequent in Hungary both in sexually transmitted infections and in the cancers of head and neck.

Comprehensive regression analysis of hepatitis B virus X antigen level and anti-HBx antibody titer in the sera of patients with HBV infection.

Although the pathogenetic significance of hepatitis B virus x protein (HBxAg) in chronic hepatitis, liver cirrhosis, and primary hepatocellular carcinoma has already been studied, the comparative analyses of both the actual serum HBxAg levels and antibody production against various HBx epitopes have been examined to lesser extent. We have simultaneously investigated the relationship between antibody production (IgG and IgM) against the HBxAg fragments and HBxAg level in the sera of patients with acute (14) or chronic hepatitis (80) and symptomless carriers (12). A recently developed sandwich-type ELISA was used for the quantitative measurements of HBxAg. Overlapping recombinant and synthetic antigens were used to map the fine epitope specificities of circulating anti-HBx antibodies. In acute hepatitis, we have found high and homogenous correlation in the IgM type immune responses against all the examined HBxAg regions. Moreover, strong correlation has been observed between IgG type immune responses to a characteristic C-terminal region (C1: 79-117) and the longest fragment (X: 10-143). Moderate correlation has been found between HBxAg concentration and the IgG type anti-HBx antibody levels against C-terminus of HBxAg in patients with chronic hepatitis. In the case of symptomless carriers, there were also demonstrable associations in the immune responses against the C-terminal sequences; however, significant correlations were found for antibody production against the N-terminal region as well. The examinations show that the C-terminal sequence, responsible for transactivation, promotes an efficient IgG antibody response in all three groups of patients, whereas the negative regulator N-terminal part of the HBxAg molecule for the most part does not trigger antibody production. This suggests that the immune responses against various - biologically active - epitopes of the HBxAg may have a different role in the pathogenesis of hepatitis and may be used as prognostic markers in human HBV infections.

Sandwich type ELISA and a fluorescent cytometric microbead assay for quantitative determination of hepatitis B virus X antigen level in human sera.

The hepatitis B virus X protein (HBxAg) is responsible for severe complications of HBV infections including primary hepatocellular carcinoma. A sandwich type ELISA and a flow cytometric microbead assay for quantitative determination of serum levels of Hbx-Ag are introduced. We have previously developed monoclonal antibody families against well-conserved epitopes on HbxAg, characterized by different immunohistochemical and immunoserological techniques. Special selection of the antibody pairs provided highly sensitive and highly specific tools for quantitative immunoassay development. The resulting assays were tested on human sera (208 samples) collected from patients suffering from different clinical forms of HBV infection. The sensitivity range of the sandwich type ELISA was between 4 and 2000 ng/ml as measured on both the recombinant antigen and the sera of chronic hepatitis patients. A further flow cytometric microbead assay was established and tested in parallel with the ELISA. The quantitative results of these two immunoserological techniques were in strong correlation and they were found to be highly specific and sensitive on clinical samples. The HBxAg ELISA technique is applicable for routine clinical laboratory measurements, and our HBxAg microbead technique is recommended for complex multiparametric measurements combined with other markers.

Molecular comparison of echovirus 11 strains circulating in Europe during an epidemic of multisystem hemorrhagic disease of infants indicates that evolution generally occurs by recombination.

We compared echovirus 11 (E11) strains implicated in a severe epidemic in Hungary in 1989 with the prototype E11 strain Gregory and with other E11 strains, most of which were isolated over the same period in Europe (Finland, The Netherlands, Romania, Russia) from sporadic cases or from environmental water. Partial sequencing indicated that the Hungarian strains were closely related to each other and to most European strains. They were particularly closely related to one Romanian strain associated with a sporadic case of hemiparesis and several Finnish strains isolated from environmental water. Sequencing of the complete genomes of one Hungarian strain, the Romanian strain, and one Finnish strain revealed differences of only a few nucleotides in the 5' half of the genome, including the 5' nontranslated region (5'-NTR) and the capsid coding region. However, significant differences were observed in the nucleotide sequences of the 3' half of the genome (nonstructural viral protein region and 3'-NTR), indicating that these strains evolved recently and independently by genetic recombination with other unknown E11 or enterovirus strains.

[Viral co-infections in hepatitis C: HBV, HBV-C/HGV and TTV studies]. / Víruskoinfekciók krónikus hepatitis C-vírus-fertózésben: HBV-, GBV-C/HGV- és TTV-vizsgálatok.

BACKGROUND/AIMS: The prevalence of co-infections with hepatitis B virus (HBV) and novel hepatitis viruses GBV-C (Hepatitis G virus, HGV) and TT virus (TTV) in chronic hepatitis C (HCV) infection has been studied. In patients with chronic hepatitis C and in asymptomatic healthy HCV carriers, the influence of these agents on the course of HCV infection was assessed. METHODS: a total of 110 HCV-positive individuals, among them 77 patients with chronic hepatitis C--50 of them treated with interferon (IFN)--and 33 HCV carriers with normal alanine aminotransferase have been investigated. HBV-DNA, HGV RNA and TTV DNA were detected by PCR, to determine HBsAg and anti-HBc ELISA technic has been used. RESULTS: In the healthy population, the prevalence of anti-HCV was 0.3%, HBsAg 0.09%, anti-HBc 2.5%, HGV RNA 8.0% and TTV DNA 18.5%, respectively. In chronic hepatitis C HBsAg (accompanied with HBV-DNA) occurred in 1.29%, anti-HBc 25.97%, HGV RNA in 9.09% and TTV DNA in 40.25% of cases. In IFN-treated patients with sustained remission, the frequency of TTV was 20% vs. 45.7% found in non-responders. Among asymptomatic HCV-carriers, the prevalence of anti-HBc was 27.27%, HGV RNA 9.09% and TTV DNA 75.7% respectively. CONCLUSIONS: Neither previous HBV infection, nor HGV RNA and TTV DNA had apparent effect on the course of chronic HCV infection. TTV was detected with the lowest frequency in persons with sustained remission due to IFN, suggesting antiviral effect of IFN on TTV.

[Newly discovered hepatitis viruses--do they cause hepatitis indeed?]. / Ujonnan felfedezett hepatitisvírusok: de okoznak-e májgyulladást?

The paper reviews the available information on the newly discovered viruses originally supposed to cause post-transfusion hepatitis. GBV-C/Hepatitis G virus belongs to the Flaviviridae family, and can be transmitted parenterally like Hepatitis C virus. Its role in causing hepatitis or other diseases has not been proved yet. The other newly discovered viruses contain single-stranded circular DNA, with a wide range of sequence divergence. These viruses can be transmitted not only with blood and blood products but via fecal-oral route as well. They are unique among enterally transmitted viruses in the sense that the virus persists for years in the human body, therefore their genomes may be detected in the blood of the healthy population in high percentage. One of the genotypes of TTV is suspected to cause hepatitis. High TT virus load was found as an independent factor associated with the occurrence of hepatocellular carcinoma among patients with hepatitis C virus-related chronic liver disease. It is not clear yet, whether TTV-like minivirus and SEN virus cause any illnesses.