Just a week after two cases were reported in Ukraine, a case of polio has been confirmed in a toddler in Mali.
Both outbreaks were vaccine-derived poliovirus, where the virus used in the live oral vaccine returns to virulence from its weakened form. This often occurs when vaccination rates are low, allowing the strain to accumulate genetic mutations.
Most transmissions of polio occur when the faeces of an infected person contaminate something and end up in another person’s mouth. Hence, polio most prevalent in countries with poor sanitation and/or untreated sewerage.
Polio is such a contagious virus that just once case is considered an outbreak. Symptoms include headaches, fever, stiff muscles and paralysis.
There is no proven treatment for polio, with most treatment focussed on the complications of paralysis.
The Western Pacific Region, including Australia, was declared polio-free by the World Health Organisation in 2000. The National Immunisation Program provides polio immunisation for children with inactivated polio vaccine.
The Australian Government maintains a polio response plan and says that if a case was detected in Australia, “various public health measures will be required to prevent further spread. This would likely include immunisation of people who are at risk, isolation of infected people in hospital until cleared of infection and quarantine of household members in their home until cleared.”