FIG 2.

Recent H1N1 and H3N2 clinical isolates exhibit airborne transmission in the guinea pig model of influenza virus transmission. Guinea pigs were intranasally infected with A/New York City/PV02669/2019 (H1N1) (n = 4 transmission pairs) (A) or A/New York City/PV01148/2018 (H3N2) (n = 3 transmission pairs) (B) and transmission from donor guinea pigs to recipient guinea pigs was determined by assessing virus titers in nasal wash samples collected at days 2, 4, 6, 8, and 10 postinfection. Complete lines represent donors. Dashed lines represent recipients.