Cryptosporidium outbreaks and sewage release in UK rivers

The likelihood of there being a connection between the Cryptosporidium outbreak in South Devon and record quantities of sewage being released into UK rivers by water companies is relatively high. Let’s look at how sewage releases can lead to cryptosporidium outbreaks.

Direct contamination of water sources

When untreated or partially treated sewage is released into rivers and other water bodies, it can carry Cryptosporidium oocysts, especially if the sewage contains faecal matter from infected individuals. An oocyst is a hardy, thick-walled spore stage in the life cycle of certain protozoan parasites, including Cryptosporidium. It is the form of the parasite that is excreted in the faeces of infected hosts and can infect new hosts when ingested. Oocysts have a tough outer wall that provides protection against harsh environmental conditions, including chemical disinfectants like chlorine.

Rivers contaminated by sewage overflow can spread the parasite to wider areas, especially during periods of heavy rainfall or flooding, which can increase runoff and transport contaminants further downstream.

Impact on drinking water

Cryptosporidium oocysts are highly resistant to standard water treatment processes such as chlorination. If the water treatment plants are not equipped with advanced filtration and disinfection technologies, oocysts can survive the treatment process and enter the drinking water supply.

In regions where water treatment infrastructure is outdated or overwhelmed by the volume of contaminants, the risk of pathogens like Cryptosporidium entering the drinking water increases.

Sewage discharges by water companies

The reported record quantities of sewage being discharged into rivers by water companies suggest a significant and ongoing source of faecal contamination in surface waters. This increases the likelihood of Cryptosporidium being present in those waters.

The scale and frequency of these discharges indicate systemic issues with wastewater management and infrastructure, potentially leading to repeated contamination events.

Recent Cryptosporidium outbreak

The occurrence of a Cryptosporidium outbreak in Devon shortly after reports of extensive sewage discharges points to a temporal correlation. While correlation does not confirm causation, it strongly suggests a potential link.

Devon’s geography, climate, and water systems might exacerbate the spread of contaminants from sewage discharges to drinking water sources, especially if there are shared water bodies involved.

Likelihood of connection

Given the known pathways of Cryptosporidium transmission and the specific conditions reported in Devon, it is highly probable that the outbreak is connected to the sewage discharges. The presence of faecal contamination in rivers due to sewage overflow provides a direct route for the parasite to enter water sources used for drinking.

Supporting evidence and further actions

Conducting thorough water quality tests to detect the presence of Cryptosporidium oocysts in both the affected drinking water supply and the rivers receiving sewage discharges would provide concrete evidence of the link.

Coordinated investigations by public health authorities and water regulatory agencies can help trace the source of the outbreak and confirm the connection between sewage discharges and the cryptosporidiosis cases.

Mitigation and prevention

Investing in better wastewater treatment and sewage management infrastructure is crucial to prevent future contamination.

Strengthening the monitoring of water quality and enforcing regulations to minimize sewage discharges into rivers can reduce the risk of similar outbreaks.

Informing the public about the risks and encouraging practices that reduce faecal contamination of water bodies can also help mitigate the problem.

In summary, there is a significant likelihood that the Cryptosporidium outbreak in Devon is linked to the record quantities of sewage being released into UK rivers. Addressing this issue requires a multifaceted approach involving infrastructure improvements, stricter regulations, and proactive public health measures.

See also: Surfers Against Sewage

Pic; Neil Patterson, Chairman Fly Fishing Association