Cattle are major reservoirs of the provisionally named influenza D virus, which is potentially involved in the bovine respiratory disease complex. Here, we conducted a serological survey for the influenza D virus in Japan, using archived bovine serum samples collected during 2010–2016 from several herds of apparently healthy cattle in various regions of the country. We found sero-positive cattle across all years and in all the prefectural regions tested, with a total positivity rate of 30.5%, although the positivity rates varied among regions (13.5–50.0%). There was no significant difference in positivity rates for Holstein and Japanese Black cattle. Positivity rates tended to increase with cattle age. The herds were clearly divided into two groups: those with a high positive rate and those with a low (or no) positive rate, indicating that horizontal transmission of the virus occurs readily within a herd. These data demonstrate that bovine influenza D viruses have been in circulation for at least 5 years countrywide, emphasizing its ubiquitous distribution in the cattle population of Japan.
Influenza D virus has been found to cause respiratory diseases in livestock. We surveyed healthy dromedary camels in Ethiopia and found a high seroprevalence for this virus, in contrast to animals co-existing with the camels. Our observation implies that dromedary camels may play an important role in the circulation of influenza D virus.
Influenza (flu) D virus, a possible causative agent of bovine respiratory disease, is
genetically classified into three clusters: D/OK-, D/660-, and D/Japan-lineages. To
evaluate antigenic heterogeneity among these clusters, we compared antibody titers to each
lineage virus using bovine sera collected over time following virus infection. Antibody
titers to D/Japan-lineage virus rose rapidly in the acute phase of infection, and were 4
times higher than those to the other clustered viruses. In the later phase of infection,
titers to D/Japan-lineage virus were equivalent to those to D/OK-lineage virus, and still
higher than those to D/660-lineage virus. These results suggest the existence of common
and lineage-specific antigenic epitopes in the hemagglutinin-esterase-fusion protein of
flu D viruses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.