Between the 1930s and 1960s, there were approximately 40,000 cases of paralytic poliomyelitis recorded in Australia. Actual numbers of the polio infection could be up to 100 times greater. Only approximately one in 100 cases of poliomyelitis cause complete paralysis thereby requiring hospitalisation and mandatory reporting. However, a large percentage of the 'non-paralytic' and non-reported polio infections would still have caused considerable damage to the motor neurons.