Molecular characterisation of equine group A rotaviruses in Ireland (2011-2015).

This study investigates the molecular makeup of Group A rotaviruses in horses in Ireland between 2011 and 2015, with a focus on two particular genotypes. The research indicates these genotypes to be prevalent in foals in Ireland with a similar distribution in other countries.

Overview of the Research

• The research focused on understanding the molecular epidemiology of equine Group A rotaviruses (RVAs) in Ireland for a period of five years (2011 to 2015). RVAs are a type of virus that can cause diarrhoea and other gastrointestinal problems in foals.

Methodology and Findings

• A total of 438 diagnostic specimens were collected from foals with digestive disease. These samples were tested using an immunochromatographic assay, a quick test used to detect the presence of targeted viruses. Of these samples, 102 (or 23.3%) were positive for RVA.
• The viral genotypes were determined for 76 of these positive samples. A genotype refers to the genetic constitution of a particular virus, which determines its characteristics and behavior.
• The majority of isolates (89.5%) were identified as the G3 genotype, while a smaller portion (10.5%) were identified as G14.
• Further ‘P’ genotyping characterised 18 RVAs, all of which were P[12]. ‘P’ genotyping refers to another dimension of rotavirus genetic variation, related to the viral protein VP4.
• It was noted that G3P[12] and G14P[12] were the most common genotypes of RVA found in foals in Ireland. This distribution was found to be similar to other countries, and was consistent with previous studies carried out in Ireland from 1999 to 2005.

Phylogenetic Analysis and International Context

• The researchers performed a phylogenetic analysis on the identified viruses. This is a type of analysis that infers the evolutionary relationships and ancestry of different species or, in this case, virus genotypes.
• This analysis showed that the Irish G3P[12] and G14P[12] RVAs were closely related to equine RVAs recently observed in other parts of the world, including Europe, Brazil, and South Africa.
• The genotypes were also found to be related to a particular vaccine strain known as H-2. This is significant as it could potentially indicate the effectiveness of this vaccine in controlling these prevalent strains of the virus.