Sever's disease or calcaneal apophysitis is usually considered to be due to damage or a disturbance in this area of growth. The two growth areas of the calcaneus can be seen on this x-ray. The smaller area to the back of the heel is normal.hat are the long term consequences of heel pain in the child (Severs disease or Calcaneal apophysitis): This condition is self limiting-it will go away when the two parts of bony growth join together-this is natural.
So, a virus must have a host cell (bacteria, plant or animal) in which to live and make more viruses. Outside of a host cell, viruses cannot function. For this reason, viruses tread the fine line that separates living things from nonliving things.
Due to a number of factors, such as internal structure, outer coating, and environment conditions, viruses display a huge range of time in how long they can persist in an infectious state. Some viruses require water to remain viable, others require a particular temperature range, others still do better out of direct light.