Volume 28, Number 3—March 2022
Research
Higher Viral Stability and Ethanol Resistance of Avian Influenza A(H5N1) Virus on Human Skin
, Takaaki Nakaya, Hajime Miyazaki, Naoto Watanabe, Takuma Yoshida, Tomo Daidoji, Yoshito Itoh, and Hiroshi Ikegaya
Table 5
Survival times and half-lives of various recombinant viruses on a plastic surface*
| Subtype† |
Median survival time (95% CI), h‡ |
Median half-life (95% CI), h§ |
||
|---|---|---|---|---|
| 4 (log10 FFU) |
3 (log10 FFU) |
2 (log10 FFU) |
||
| rH5N1-H5N3-NA | 8.15 (6.86–9.62) | 0.41 (0.34–0.51) | 0.55 (0.45–0.68) | 0.82 (0.67–1.02) |
| rH5N1-H5N3-HA | 8.17 (6.88–9.63) | 0.41 (0.34–0.51) | 0.55 (0.45–0.68) | 0.83 (0.68–1.02) |
| rH5N3-H5N1-NA | 23.68 (21.26–26.25) | 1.14 (1.02–1.28) | 1.52 (1.36–1.71) | 2.28 (2.04–2.57) |
| rH5N3-H5N1-NS | 7.74 (6.59–9.03) | 0.39 (0.33–0.48) | 0.53 (0.44–0.64) | 0.79 (0.65–0.96) |
| rH5N3-H5N1-M | 8.75 (7.52–10.11) | 0.45 (0.38–0.54) | 0.60 (0.50–0.72) | 0.90 (0.75–1.08) |
| rH5N3-H5N1-HA | 7.69 (6.59–8.93) | 0.39 (0.33–0.47) | 0.52 (0.44–0.63) | 0.78 (0.65–0.95) |
*FFU, focus-forming unit. †A/crow/Kyoto/53/04 (H5N1) recombined with the NA and HA genes of A/Duck/Hong Kong/820/80 (H5N3) are defined as rH5N1-H5N3-NA and rH5N1-H5N3-HA. In addition, A/Duck/Hong Kong/820/80 (H5N3) recombined into the NA, NS, M, and HA genes of A/crow/Kyoto/53/04 (H5N1) was defined as rH5N3-H5N1-NA, rH5N3-H5N1-NS, rH5N3-H5N1-M, rH5N3-H5N1-HA. ‡The elapsed time was used as the explanatory variable (x-axis), and the logarithmic virus titer was used as the explained variable (y-axis). A linear regression analysis with logarithmic link function was performed for each virus to create a curve of regression (Appendix Figure 3). Because the detection limit of each influenza virus titer was 101 FFUs, the X value (when the Y value of the regression curve was 1.0) was used as the survival time. §The half-life of each virus was calculated from the slope of each regression curve when the amount of virus remaining on the surface was 2, 3, or 4 log10 FFUs.