Changes

2. Haematology.

2. Haematology.

3. Analysis of faeces;  use of an '''Elisa''' to detect the virus antigen or detecting the virus DNA, using a '''PCR''' (Polymerase chain reaction.)

3. Analysis of faeces;  use of an '''ELISA''' to detect the virus antigen or detecting the virus DNA, using a '''PCR''' (Polymerase chain reaction.)

4. Evidence of exposure to virus - detect antibody to virus within the blood.

4. Evidence of exposure to virus - detect antibody to virus within the blood.