A cluster of salivirus A1 (Picornaviridae) infections in newborn babies with acute gastroenteritis in a neonatal hospital unit in Hungary

Abstract

Salivirus (family Picornaviridae) may be associated with acute gastroenteritis in humans, but there have been no reports of salivirus outbreaks. Salivirus A1 infection with faecal virus concentrations of 2.1-2.6 × 10(9)/g were identified retrospectively in newborn babies, between the ages of 1.5 and 5 days, with apparent clinical symptoms of diarrhea (100 %), fever (40 %), vomiting (40 %), and loss of appetite (40 %) in a neonatal hospital unit in Hungary in July 2013. The complete genome sequence of the salivirus (including the 5'-terminal end) was determined. Salivirus mono-infection may be associated with gastroenteritis in babies who are a few days old. Salivirus testing should be done in public health laboratories in gastroenteritis outbreaks with unknown etiology.

Saliviruses-the first knowledge about a newly discovered human picornavirus

“…The longest and potentially the complete genome of SaV‐A1 was determined recently, which means that none of the 3 original SaV‐A1 strains (NG‐J1/Nigeria/2007, GQ179640; 02394‐01/USA/2002, GQ184145; and Australia/1984, GQ253930) represent the full genome sequence lengths. The longest available salivirus genome is the strain Baja/5332/Hungary/2013 (KT240115) with 8021 nucleotides excluding the poly(A) tail . This salivirus genome encodes a single polyprotein (2369 aa's), which undergoes a cleavage cascade performed by virus‐encoded enzymes, to give the final virus proteins (Figure A).…”

“…In 2016, a total of 10 complete or near‐complete (available complete coding sequence) salivirus genomes (SaV‐A1, N = 8, and SaV‐A2, N = 2) are available in GenBank. The longest and potentially the complete genome of SaV‐A1 was determined recently, which means that none of the 3 original SaV‐A1 strains (NG‐J1/Nigeria/2007, GQ179640; 02394‐01/USA/2002, GQ184145; and Australia/1984, GQ253930) represent the full genome sequence lengths. The longest available salivirus genome is the strain Baja/5332/Hungary/2013 (KT240115) with 8021 nucleotides excluding the poly(A) tail .…”

“…A conserved aa motif of rRQ↓G (conserved aa in uppercase, frequent aa in lowercase) surrounded the junctions of L↓VP0, 2A↓2B, 2B↓2C, 2C↓3A, and 3B↓3C is identifiable in all of the known salivirus sequences. On the basis of the presence of this rRQ↓G motif, an alternative/probable VP1↓2A cleavage site that could be identifiable in all known salivirus genomes 26aa upstream of the initially predicted VP1↓2A junction was suggested (Figure A).…”

“…The open reading frame encoding the salivirus polyprotein is preceded by a 763 nucleotide long 5′ untranslated region (UTR) . This is predicted to have a complex secondary/tertiary structure involved in genome replication (Figure A). The 5′UTR of salivirus was predicted to contain type V internal ribosomal entry site (IRES) .…”

Prevalence and Clinical Profile of Human <b><i>Salivirus</i></b> in Children with Acute Gastroenteritis in Northern Italy, 2014–2015

“…SalV has a single-stranded RNA genome of around 7,633 nt organized in a typical Picornavirus genome. Although this virus is related, but distinct, to the genus Ko buvirus, SalV forms a genus that presently includes a single genotype with 2 clusters [9]. SalV (previously called Klassevirus) is associated with diarrhea and has been detected in feces from both gastroenteritis patients and healthy subjects on all continents, as well as in sewage from Spain and Hong Kong, suggesting a widespread geographic distribution [8].…”