Little evidence has been found of avian or equine influenza infecting humans, in a study carried out in Mongolia.
Avian and equine influenza virus have been repeatedly shown to circulate among Mongolia’s migrating birds or domestic horses.
In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a study exploring cross-species influenza transmission.
Blood was drawn upon enrollment, and again after 12 and 24 months.
Participants were contacted monthly for 24 months and asked about episodes of influenza-like illnesses.
Study members confirmed to have acute influenza A infections had respiratory swabs taken for analysis and comparison with equine, avian, and human influenza viruses.
Over the two years of follow-up, investigations into 100 influenza-like illnesses were conducted.
Thirty-six were identified as influenza A infections, but none yielded evidence of the avian or equine influenza virus.
While 37 participants had detectable antibody titers against the studied equine and avian viruses, none was statistically associated with avian or horse exposures.
“As elevated antibodies against seasonal influenza viruses were high during the study period, it seems likely that cross-reacting antibodies against seasonal human influenza viruses were a cause of the low-level sero-reactivity against avian influenza virus or equine influenza virus,” the researchers wrote.
“Despite the presence of AIV and EIV circulating among wild birds and horses in Mongolia, there was little evidence of avian influenza virus or equine influenza virus infection in this prospective study of Mongolians with animal exposures,” the authors concluded.
The findings of the research were published this month in the open-access journal, PLoS ONE.
Khurelbaatar N, Krueger WS, Heil GL, Darmaa B, Ulziimaa D, et al. (2014) Little Evidence of Avian or Equine Influenza Virus Infection among a Cohort of Mongolian Adults with Animal Exposures, 2010–2011. PLoS ONE 9(1): e85616. doi:10.1371/journal.pone.0085616
The full study can be read here.