| Popis: |
Rotavirus A (RVA) is the main causative agent of viral gastroenteritis in children and young animals worldwide. Molecular epidemiology is primarily based on genotyping the VP7 and VP4 genome segments which gives a binary classification (G and P genotypes). Molecular diversity of RVA strains in humans is high and some of those strains have zoonotic origin. During season 2018/2019 we have tested 188 faecal samples from hospitalized patients (mostly children under the age of five years, among which 22 newborns) in Zagreb, Osijek and Split. All patients were positive for RVA by immunochromatographic assay. Semi-nested multiplex PCR for VP7 and VP4 RVA genotyping coupled with Sanger sequencing of amplified VP7, VP4 and VP6 RT-PCR fragments were applied. The G or P genotype was determined in 187 samples and G/P genotype combination in 169 samples. The most common G genotypes were G3 (55.1%), G1 (12.9%), G2 (6.4%), G9 (2.7%), G4 (1.6%), G10 (1.1%), mixed G genotypes (16%) and untypeable G genotype (4.8%). The P genotypes were predominantly P[8] (86.1%), followed by P[4] (4.8%), P[9] (0.5%), mixed P genotypes (3.7%) and untypeable P genotype (4.8%). In total there were nine G/P combinations ; G3P[8], G1P[8], G2P[4], G4P[8], G9P[8] and less common G10P[8], G2P[8], G9P[4] and G3P[9]. Among G3 strains 48.5% were the emerging G3 equine-like intergenogroup reassortant RVA strains. Another notable finding is the first detection of unusual DS-1-like G1P[8] intergenogroup reassortant strains in Europe. G10 strains detected in children from eastern Croatia are possibly having the zoonotic bovine origin. However, other G genotypes shared between humans and animals in Croatia (G2, G4, G9) show different evolutionary direction. The ongoing studies on spatio-temporal molecular epidemiology of RVA strains in Croatian ecosystem will fill the knowledge gaps and provide useful database when considering the potential introduction of RVA vaccines in national immunisation program. |
