Clinical responses to infection.

(A–C) Two weeks after booster vaccination, ferrets were challenged intranasally with 106 PFU of Perth/16. (D–F) Unvaccinated ferrets were challenged intranasally with 1×106 PFU of NY/21 or Perth/16. (A, D) Body weight and (B, E) temperature were measured daily. Data shown are normalized to the individual animals’ weight or temperature on the day of challenge (day 0). (C, F) Nasal washes were obtained on days 0–9 and virus titers in the nasal washes were measured. Error bars represent 95% confidence intervals. “Mock”, unvaccinated mock-infected animals; “Naïve”, unvaccinated animals challenged with Perth/16; “TIV”, vaccinated animals challenged with Perth/16. “H3N2”, unvaccinated animals challenged with Perth/16; “H1N1pdm”, unvaccinated animals challenged with NY/21. † indicates p<0.0001; * indicates 0.0001

(A–C) 加强免疫接种两周后，对雪貂经鼻攻毒1×10⁶ 噬斑形成单位（Plaque Forming Unit, PFU）的Perth/16毒株。(D–F) 未免疫雪貂经鼻攻毒1×10⁶ PFU的NY/21或Perth/16毒株。(A、D) 每日测量动物体重与体温，所有展示数据均以攻毒当日（第0天）对应个体的体重或体温为基准进行归一化处理。(C、F) 于攻毒后第0至9天采集鼻洗液标本，检测其中的病毒滴度。误差棒代表95%置信区间。其中，"Mock"指代未免疫且经模拟感染处理的动物；"Naïve"指代未免疫并以Perth/16毒株攻毒的动物；"TIV"指代免疫后以Perth/16毒株攻毒的动物。"H3N2"指代未免疫并以Perth/16毒株攻毒的动物；"H1N1pdm"指代未免疫并以NY/21毒株攻毒的动物。†表示P<0.0001；*表示P=0.0001。