What sewage surveillance in London tells us about polio risk in 2026

According to the UK Health Security Agency, there have been two unrelated detections of vaccine derived poliovirus 2 in London in 2026. Both samples were collected at Beckton Sewage Treatment Works. The first was collected early January and the second in March. The most recent collection was consistent with a fresh importation and demonstrates why high levels of vaccination are important in disease control.

The Agency has reassured the community there is no evidence of local transmission and the risk to the community is low.

This isn't an isolated event in a high-income country. In late 2025, wild poliovirus type 1 was detected in German sewage, also through routine environmental surveillance.

How sewage surveillance works

Of interest is the criteria for sewage sampling in a particular area:

• areas with low vaccine coverage for the childhood immunization program
• areas with pockets of under-vaccinated communities
• areas with higher risk of importation from a country where wild poliovirus or vaccine derived poliovirus is circulating, or where the live oral poliovirus vaccine is still used

The Health Security Agency has also provided an interesting flowchart of sewage surveillance and its role in the detection and prevention of polio. See: Environmental surveillance for polio.

Why this matters for Australia

Falling childhood vaccine rates globally are a reason for concern. Australia is not immune to this. The polio outbreaks of the 1950's are a distant memory. Most of the community would have had no direct experience of the disease. It's important that we continually remind travellers that our current herd immunity protects individuals while living in Australia, but they are on their own in many overseas locations. Australia was declared polio free in 2000. For a broader picture of where global eradication efforts stand, see our earlier article on the polio eradication program.

Polio risk to travellers

The risk of exposure to polio for most travellers is very low. This presumes that most travellers are fully vaccinated. We know that 94-95% of children who are born in Australia receive their childhood vaccinations.

The risk of international exposure to the wild virus is very low with only 2 countries reporting cases in the last 12 months (Afghanistan, Pakistan). The main concern for travellers is the potential exposure to the vaccine derived poliovirus.

The Global Polio Eradication Initiative (GPEI) maintains a public dashboard tracking countries reporting both cases and positive environmental samples. The two London detections have already been added.

Most high-risk countries have poor public health infrastructures where surveillance is limited, and safe water cannot be assured.

An adult polio booster (IPOL) might be offered to those intending to visit these countries if they have not had a booster in the last 10 years. This group includes long-term expatriate workers, international volunteers working in NGOs, and those intending basic travel with high-level community exposure.

The risk to travellers visiting high income countries reporting polio in wastewater, such as the United Kingdom, would be very low. However, frequent travellers might be offered polio as a combination with the triple antigen if indicated. Two combination vaccines are available in Australia (Boostrix IPV, Adacel Polio).

Planning travel? Check your polio vaccination status

If you're heading overseas, particularly to lower-income countries, working long-term as an expatriate, or volunteering with an NGO, it's worth reviewing your polio vaccination history. A booster may be recommended if you haven't had one in the last 10 years. If you'd like to review your vaccination status before travelling, book a telehealth consultation with one of our travel doctors.