In England, notifiable diseases are outlined under the Health Protection (Notification) Regulations 2010.
When the regulation was created, the addition of chickenpox was considered, however, it was not included. This is because a provision is in place requiring notification of any infectious diseases which may pose a significant risk to human health. This was deemed to cover exceptional cases where public health action would be needed.
The Department keeps the diseases which are notifiable in England under review.