Genomic Structure, Replication and Epidemiology of Norovirus

Norovirus is an RNA virus that causes commonly sporadic gastroenteritis or foodborne and waterborne outbreaks in children and adults. Its genomic organization includes three open reading frames (ORF) ORF1, ORF2 and ORF3 which encode the structural and the nonstructural proteins. ORF1 encodes the non-structural polyprotein, ORF2 encodes VP1 which is the structural major capsid protein and ORF3 encodes structural protein VP2. Noroviruses are subdivided into five genogroups according to the nucleotide sequence similarity. Genogroups infecting humans are GI, GII and GIV. Genogroup GIII infects bovine species, genogroup GV infects murine species. Due to the lack of an in vitro culture system, noroviruses replication is not elucidated, however several studies are carried out using the culture of other genogroups infecting animals. Around the world and in Turkey as well as norovirüs can infect every age groups of people, outbreaks commonly occur in communities containing rather children and elderly population. Genogroup II and especially genotype GII.4 strains are responsible from the bulk of these outbreaks. Genogroup II is followed by GI and GIV is seen less common. GI and GII genogroups were detected in an outbreak that occurred in Turkey in 2008. In a few studies had been carried out about norovirus in our country genogroup GII is detected more often. Especially, studies involved children with acute gastroenteritis are prominent and approximately 10-17% norovirüs positivity is detected. In the laboratory diagnosis of noroviruses reverse transcriptase-polymerase chain reaction is the gold standard to determine the genogroups, however ELISA and immunochromatographic rapid diagnostic tests are in common use for quick results

Hepatitis E Infection in Solid Organ Transplant Recipients in Turkey

Background: Hepatitis E virus is a re-emerging pathogen with an increase in human cases that can lead to chronic infection in immunosuppressed patients. Turkey is located between Asia and Europe, 2 regions with distinct epidemiological and clinical features of hepatitis E virus infection. This multicenter cross-sectional study aimed to investigate the prevalence of hepatitis E virus infection in liver and kidney transplant recipients in Turkey and to determine the role of possible transmission factors

Evaluation of the results of MOTAKK hepatitis C virus RNA genotyping and hepatitis delta virus external quality assessment programs during 2015-2016

Background/Aims: To evaluate the HCV RNA genotyping and HDV RNA tests that are performed in molecular microbiology laboratories in Turkey as part of a national external quality assessment programme, MOTAKK (Molekuler Tanida Kalite Kontrol) (English translation: Quality control in molecular diagnostics)