Bovine coronavirus in Uruguay: genetic diversity, risk factors and transboundary introductions from neighboring countries

Abstract

Bovine coronavirus (BCoV) is a recognized cause of severe neonatal calf diarrhea, with a negative impact on animal welfare, leading to economic losses to the livestock industry. Cattle production is one of the most important economic sectors in Uruguay. The aim of this study was to determine the frequency of BCoV infections and their genetic diversity in Uruguayan calves and to describe the evolutionary history of the virus in South America. The overall detection rate of BCoV in Uruguay was 7.8% (64/824): 7.7% (60/782) in dairy cattle and 9.5% (4/42) in beef cattle. The detection rate of BCoV in samples from deceased and live calves was 10.0% (6/60) and 7.6% (58/763), respectively. Interestingly, there was a lower frequency of BCoV detection in calves born to vaccinated dams (3.3%, 8/240) than in calves born to unvaccinated dams (12.2%, 32/263) (OR: 4.02, 95%CI: 1.81-8.90; p = 0.00026). The frequency of BCoV detection was higher in colder months (11.8%, 44/373) than in warmer months (1.5%, 3/206) (OR: 9.05, 95%CI: 2.77-29.53, p = 0.000013). Uruguayan strains grouped together in two different lineages: one with Argentinean strains and the other with Brazilian strains. Both BCoV lineages were estimated to have entered Uruguay in 2013: one of them from Brazil (95%HPD interval: 2011 and the other from Argentina (95%HPD interval: 2010-2014). The lineages differed by four amino acid changes, and both were divergent from the Mebus reference strain. Surveillance should be maintained to detect possible emerging strains that can clearly diverge at the antigenic level from vaccine strains.

Molecular epidemiological survey and phylogenetic analysis of bovine respiratory coronavirus in Japan from 2016 to 2018

“…BCoV infection was most commonly detected from late autumn to early spring (November to March). This trend was similar to those in other studies [2,19]. An experimental infection showed that BCoV persistently infects the respiratory tissues of cattle [11].…”

“…Cattle with more than 12 months old might have neutralizing antibody acquired by BCoV-infection in the past or vaccination, and it might inhibit the BCoV-infection in adult cattle. Castles et al reported that the infection rate of calves born to vaccinated dams was significantly lower than that of calves born to unvaccinated dams [2]. Another study reported that calves with high neutralizing antibodies acquired through passive immunity were mostly protected against BCoV infection [1].…”

Dissecting Transcription Factor-Target Interaction in Bovine Coronavirus Infection

“…The virus results in three distinct symptoms: calf diarrhea, winter dysentery with hemorrhagic diarrhea in adults, and respiratory infection in cattle of all ages [4,5]. Neonatal calf diarrhea (NCD) is the major cause of death in unweaned heifers [6,7]. These symptoms are devastating for the agricultural industry, with impacts including the cost of treatment and prophylaxis, increased vulnerability to additional diseases, increased mortality rates, long-term lowered growth rates, and lowered milk production [8,9].…”

“…These symptoms are devastating for the agricultural industry, with impacts including the cost of treatment and prophylaxis, increased vulnerability to additional diseases, increased mortality rates, long-term lowered growth rates, and lowered milk production [8,9]. Widespread BCoV infections can have disastrous effects, especially in countries like Uruguay or Vietnam, where cattle production is a primary source of income and the overall BCoV detection rate is 7.8% [7] and 33.3% [1], respectively. Current diagnostic method involves sampling feces and intestinal contents and performing reverse transcription-polymerase chain reactions (RT-PCR) to assess for BCoV [7][8][9].…”

Orta Çin’de Sığır Koronavirusun Tam Uzunlukta Spike Genine Dayalı Tespiti ve Moleküler Karakterizasyonu

“…Bovine coronavirus (BCoV) is a lineage A member of the species Betacoronavirus, belonging to the family Coronaviridae in the order Nidovirales, as assigned by the International Committee on Taxonomy of Viruses (ICTV) [1] .…”