A Proposed Modeling Approach for Comparing the Heat Inactivation Susceptibility of Viruses

Intra-Family and Inter-Family Comparisons for Viral Susceptibility to Heat Inactivation

“…An example of a power function fit to empirical temperature inactivation data is shown in Figure 1. Additional examples of the use of both the z value approach and the power function approach for modeling heat inactivation at non-empirical temperatures, based on the same data set, have been reported previously [37].…”

“…The rationale for pursing a different approach for modeling heat inactivation susceptibility of viruses, and the approach itself, have been described in detail previously [37]. In brief, this alternative approach consists of assigning a power function line fit directly to a plot of D vs. temperature.…”

“…As discussed previously [37], this has been due to the fact that empirical studies of heat inactivation of viruses have not been performed at standardized conditions of temperature and time, and it turns out that both of these factors play important roles in determining heat inactivation efficacy. So even if the inactivation matrices have been duplicated or approximated across different studies, the exact conditions of temperature and time have rarely been directly comparable.…”

“…In a recent report [37], we have described a modeling approach intended to allow inter-study evaluation of heat inactivation results as a means of circumventing the difficulties in conducting the inter-family and inter-species comparisons described above. This approach is based on the power function relationship between decimal reduction value (D, the time required to inactivate 1 log 10 of a virus) and temperature.…”

“…In the present survey of the viral heat inactivation literature, this modeling approach has been used to facilitate direct comparison of heat inactivation susceptibility results for a number of virus families, including both enveloped and non-enveloped viruses. This survey is expanded greatly relative to the few examples discussed in our previous report [37]. The z value (a more traditionally used value corresponding to the temperature required to cause a one log 10 change in D) obtained for each of the various viruses has also been assembled and compared.…”