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 1
Survival times and half-lives of various subtypes of influenza 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) |
||
| H5N1-Ky | 26.35 (23.84–29.01) | 1.28 (1.15–1.43) | 1.71 (1.54–1.91) | 2.56 (2.30–2.86) |
| H5N1-Eg | 26.30 (23.64–29.14) | 1.27 (1.13–1.43) | 1.69 (1.51–1.90) | 2.54 (2.27–2.85) |
| H7N9 | 7.97 (6.82–9.27) | 0.40 (0.34–0.49) | 0.54 (0.45–0.65) | 0.81 (0.67–0.98) |
| H5N3 | 10.01 (8.35–11.91) | 0.52 (0.42–0.65) | 0.70 (0.57–0.87) | 1.05 (0.85–1.30) |
| H5N9 | 8.88 (7.67–10.23) | 0.46 (0.39–0.55) | 0.61 (0.51–0.73) | 0.92 (0.77–1.09) |
| H3N2 | 9.28 (7.94–10.79) | 0.48 (0.40–0.58) | 0.64 (0.54–0.77) | 0.96 (0.80–1.16) |
| H1N1-PR8 | 9.70 (8.29–11.30) | 0.51 (0.42–0.61) | 0.68 (0.56–0.82) | 1.01 (0.85–1.22) |
| H1N1-Ok-pdm | 8.78 (7.60–10.10) | 0.45 (0.38–0.54) | 0.60 (0.51–0.72) | 0.91 (0.76–1.08) |
*FFU, focus-forming units; H5N1-Ky, A/crow/Kyoto/53/04 (H5N1); H5N1-Eg, A/chicken/Egypt/CL6/07 (H5N1); H7N9, A/Anhui/1/23 (H7N9); H5N3, A/Duck/Hong Kong/820/80 (H5N3); H5N9, A/Turkey/Ontario/7732/66 (H5N9); H3N2, Clinical strain (H3N2); H1N1-PR8, A/Puerto Rico /8/1934 (H1N1); H1N1-Ok-pdm, A/Osaka/64/2009 (H1N1). †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 1). 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 times. ‡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.