Brazil has recently confirmed cases of highly pathogenic avian influenza (HPAI) in wild birds. Avian influenza is mainly caused by:
(a) bacteria
(b) fungus
(c) virus
(d) parasite
Ans.(c)
Sol. Avian influenza (also known as bird flu) is a highly contagious viral disease that primarily affects birds, but some strains can also infect humans.