Herpes virus is only deadly to puppies during the first three weeks of life, because a newborn puppy's average body temperature does not reach 100 degrees until 3 weeks of age. (vin.com)
Younger babies have an average body temperature of 97 - 100.3 F, so keep them only slightly warmer than you would tolerate. (wikihow.com)
The average body temperature for humans is 37 degrees Celsius, but it fluctuates throughout the day by about 1 degree Celsius, being highest in the afternoon and lowest just before dawn. (sciencedaily.com)