Detection of Poliovirus in Western Australia Wastewater
A strain of poliovirus has been identified at a wastewater treatment facility in Western Australia, prompting authorities to closely monitor the situation. The Australian Centre for Disease Control is collaborating with the state government, the National Polio Surveillance Program, and expert advisory groups to evaluate the detection and coordinate any necessary actions. The virus was found at the Subiaco wastewater treatment plant.
The detected strain is classified as vaccine-derived poliovirus, which is uncommon but can occur in regions where the oral polio vaccine is still administered. This suggests that the source may be an individual who recently traveled to Perth from a country where the oral vaccine is used.
This marks the first time such a strain has been identified in Australia, a country that does not use the oral vaccine. Similar cases have been reported in other countries, including parts of Europe in 2024 and 2025, though these instances did not result in any polio cases.
Dr Clare Huppatz, WA’s Chief Health Officer, emphasized that the risk to the general population is very low. “While this is a significant finding, there is no evidence of the disease spreading within Western Australia,” she stated. Australia was officially declared polio-free in 2000, and this incident does not alter that status.
Professor Zoe Wainer, director general of the Australian Centre for Disease Control, highlighted that the detection demonstrates the effectiveness of the country’s disease surveillance and monitoring systems. “Wastewater surveillance is designed to provide early warnings, allowing health authorities to take precautionary measures,” she said. “This is an environmental detection, not a clinical case. No polio cases have been identified, and there is no indication of local transmission.”
Understanding Poliovirus and Its Risks
Sanjaya Senanayake, an infectious diseases specialist and associate professor of medicine at the Australian National University, explained that poliovirus can cause severe complications, including paralysis and death, particularly in children. “Global vaccination efforts over several decades have nearly eradicated the disease, but we are not yet at the point of complete elimination,” he noted.
Senanayake pointed out that outbreaks of polio in the region have been rare, though they have occurred in countries such as the Philippines, Indonesia, and Papua New Guinea. He outlined two primary ways people can contract polio: through mutated forms of the virus derived from the oral polio vaccine or through the naturally circulating virus, which remains prevalent in countries like Pakistan and Afghanistan, where vaccination programs face challenges.
High Vaccination Coverage in Western Australia
Jacqueline Stephens, an associate professor of epidemiology at Flinders University, noted that Western Australia has one of the highest childhood vaccination rates in the country, standing at approximately 92%. This high coverage plays a crucial role in preventing the spread of infectious diseases and maintaining public health.
