BACKGROUND AND OBJECTIVE: Hepatitis E virus (HEV) is mainly transmitted through contaminated water supplies which make the virus endemic in developing countries including countries of the Middle East and North Africa (MENA) region. HEV is now considered as the leading cause of enterically transmitted non-A hepatitis worldwide. Recent reports suggest potential risk of HEV transmission via blood transfusion in endemic areas. The objective of this study was to look at what has been published on HEV infection in the countries of the MENA region over the past 14 years (January 2000 August 2014) and to see whether the transfusion-transmission route of HEV has been critically evaluated. MATERIALS AND METHODS: Related articles were collected, by searching through the countries of the MENA region using Pubmed, Medline and Google Scholar. The search was conducted using predefined combination of keywords: ‘Hepatitis E Virus’, ‘Hepatitis E’, ‘Hepatitis E Infection’, ‘blood donors’ in combination with all the names of the MENA region countries which cover a population of over 380 million people. One hundred articles were reviewed, of which 25 articles were excluded; the excluded papers were written in non-English Language or had uninterpretable data. RESULTS: Published data confirm the endemicity of HEV in the MENA region. Except for Egypt (anti-HEV IgG reaches 100% in certain populations), the seroprevalence of HEV in the general population ranged from 2.3–37.5% and was higher in males than in females. Prevalence increased with age, but exposure seems to be in early life in Egypt as high prevalence was detected in young children. There were only 8 articles published on blood donors and seroprevalence of HEV in blood donors was similar to that in the general population. Only one study was a prospective one and HEV infection would be documented in transfusion recipients. Infections were traced to infected donor samples (HEV-RNA-positive). CONCLUSION: Data on the possible transmission of HEV by blood transfusion in non-endemic countries (e.g. Japan, Germany) is still controversial. In the MENA region however, the role of HEV as infectious threat to blood safety is still seriously under-investigated. More data is needed to quantify the risk of transmission. This at least requires surveillance screening of donors and recipients for markers of recent or active HEV infection using reliable and currently available simple serological test. At the present time however, serious consideration should be given to selective screening for certain groups of patients (e.g. immunocompromised, pregnant women and others) who commonly require blood transfusion and are at high risk of hepatic failure or chronicity from HEV infection.

Details Abstract Number: PE1/7 Session Title: Poster Session 1&2 Abstract Category: 1. Virology (incl. Molecular Virology, Diversity, excl. Resistance)

ABSTRACT An assay to measure avidity index (AI) was developed to diagnose incident hepatitis C virus (HCV) infections. The assay demonstrated an AI value statistically significantly lower in primary HCV infections than in chronic infections. When the assay was applied to past resolved infections, the difference in AI values was not as significant as the difference between incident and chronic infections. Lower AI values obtained in past resolved infections may be directly related to lower levels of immunoglobulin G anti-HCV in past resolved infections than in either new infections or chronic infections.

The polymerase chain reaction (PCR) method is a sensitive, specific and rapid technique for virus detection. The principles of a PCR enhanced immunoassay (PIA) are described. The method combines solid phase serological techniques with the PCR, providing a versatile and sensitive method for antibody detection. By linking the antigenicity of virus particles with their content of nucleic acid, the method provides new possibilities for virus serology: for example, antibody specificity can be coupled to viral sequence in patients with chronic infections caused by highly variable viruses such as HIV and HCV. An application of the PIA technique is described for the detection of anti-enterovirus IgM. IgM is captured to anti-human IgM-coated microwell plates. The anti-enterovirus IgM is allowed to bind crude enterovirus antigen. Bound virus is heat denatured and the released RNA is used as a template for reverse transcription PCR (RT-PCR) amplification. Amplicons are detected by hybridisation to an affinity labelled probe in a microwell colorimetric assay. In a pilot study, 18 serum specimens from patients with enterovirus infections were examined. Using a mixture of ten crude enterovirus antigens, the frequency of IgM positivity was 6/18 (33%). Titres between 1/500 and 1/100 000 were recorded. Predominantly type-specific antibodies were detected. The results were compared with a procapsid enterovirus radioimmunoassay (RIA). After further optimisation, the PIA has the potential to be a clinically useful assay for the detection of antiviral antibodies.

BACKGROUND AND AIM:The purpose of the present study was to develop enzyme immunoassay (EIA) for the detection of IgG anti-hepatitis E virus (HEV) activity using two new recombinant proteins as antigenic targets, and to evaluate these EIA with the aid of statistical methods.METHODS:Two proteins, a mosaic protein and pB166 containing region 452-617 aa of the ORF2 of the HEV Burma strain, were used to develop the new HEV EIA. This EIA was evaluated using several panels of serum specimens obtained from: (i) acutely HEV-infected patients; (ii) patients with non-A, non-C hepatitis; (iii) normal blood donors (NBD) from non-endemic countries; and (iv) experimentally infected chimpanzees.RESULTS:A new HEV EIA was developed using two new recombinant proteins. This assay was able to detect anti-HEV activity in all specimens from acutely HEV-infected patients. When NBD were tested, more than 15% of specimens were found to be IgG anti-HEV positive. All NBD anti-HEV-positive specimens were tested with overlapping synthetic peptides spanning the entire HEV ORF2-encoded protein. More than 90% of the anti-HEV-positive NBD specimens immunoreacted with an average of 15 synthetic peptides derived from different regions of the HEV ORF2 protein. These data suggest that the HEV EIA is at least 90% specific in detecting remote HEV infections.CONCLUSION:The new HEV EIA developed in the present study is a highly specific diagnostic assay for the detection of anti-HEV activity in serum specimens obtained from different epidemiologic settings.