Campylobacter And Water Contamination: Risks And Prevention

Introduction

Campylobacter is a type of bacteria that causes diarrheal disease and, according to the World Health Organization (WHO), it is one of the four leading causes of diarrheal illness worldwide.¹ The bacteria consist of several species, with the most common ones affecting humans being Campylobacter jejuni, Campylobacter coli, Campylobacter fetus, and Campylobacter lari.² Like many bacteria, Campylobacter has specific modes of transmission.

The bacteria are commonly spread through food, particularly raw or undercooked meat, unpasteurised milk, and contaminated water.¹ Contaminated drinking water is a significant risk, as Campylobacter can survive and thrive in unclean water, making it vital to ensure safe water consumption and proper water quality control to prevent the spread of the bacteria and the illnesses it causes.

Understanding campylobacter

Characteristics 

Campylobacter is a spiral-shaped bacterium, though it can also appear as S-shaped, rod-shaped, or curved.¹ It typically measures between 0.5 to 5 microns in length and 0.2 to 0.9 microns in width.² Campylobacter jejuni thrives in microaerophilic conditions, meaning it requires very low oxygen levels, and it grows best at temperatures between 37°C and 42°C.³

Transmission pathways

Campylobacter can spread to humans through a variety of pathways, often originating from contaminated environments or direct contact with infected animals. The primary methods of transmission include:^1,2

• Direct contact with contaminated water: Water sources that are polluted with Campylobacter bacteria, such as untreated drinking water or recreational water, can lead to infection
• Consumption of contaminated food and water: Eating undercooked meat, especially poultry, drinking unpasteurised milk, or consuming other contaminated food products are common ways the bacteria infect humans
• Animal-to-human transmission: Direct contact with infected animals, particularly farm animals or pets, can also result in human infection

Risks associated with campylobacter in water

Exposure to Campylobacter-contaminated water can pose significant health risks, leading to a range of symptoms and potential complications.

Health impacts

Campylobacter infection, or campylobacteriosis, typically causes gastrointestinal symptoms, such as:¹

• Diarrhoea, often with blood
• Abdominal pain
• Headache
• Fever
• Nausea, with or without vomiting

In more severe cases, Campylobacter infection can result in complications affecting several body systems, including the cardiac, neurologic, pulmonary, and immune systems. One serious potential complication is the development of Guillain-Barre syndrome (GBS), an autoimmune disorder that attacks the peripheral nerves, causing symmetrical, ascending flaccid paralysis.²

Vulnerable populations

Certain groups are at higher risk of severe illness from Campylobacter infection, including:¹

• Children
• The elderly
• Immunocompromised individuals

Sources of water contamination

Water contamination by Campylobacter often stems from environmental factors and human activities that introduce harmful bacteria into water systems.¹ One major source is agricultural runoff, which occurs when rainwater doesn't fully absorb into the ground or flow into a watercourse. Instead, it picks up contaminants like animal faeces from livestock and fertilizers used on crops. These pollutants can then make their way into nearby rivers, lakes, or groundwater, introducing Campylobacter into drinking water supplies.

Another significant contributor is untreated or poorly treated wastewater.⁴ Domestic sewage and industrial discharges, if not adequately processed, can release harmful bacteria into water systems. In regions with inadequate wastewater treatment infrastructure, this poses a significant risk of contamination, especially in communities that rely on surface water for drinking.

Natural water sources such as lakes, rivers, and groundwater can also harbour Campylobacter. These bodies of water may become contaminated through various means, including direct runoff, animal activity near water sources, or leaching from contaminated soil. Groundwater, while often considered safer, is not immune to contamination, particularly in areas where agricultural or industrial activities are prevalent.^1,2

Detection and monitoring

Campylobacter in water is detected by collecting water samples and growing the bacteria in cultures. These samples are then subjected to Polymerase Chain Reaction (PCR) testing, which is a highly sensitive method for identifying the presence of Campylobacter bacteria.⁴ Continuous monitoring of water sources for Campylobacter is crucial for reducing and preventing outbreaks of disease.

Prevention strategies

Preventing Campylobacter infections involves a variety of strategies, including:⁵

• Ensuring clean water through proper water treatment
• Implementing sanitation measures where needed
• Maintaining effective water treatment systems
• Applying disinfection methods to kill harmful bacteria
• Practising good hygiene, such as regular hand washing
• Taking care when handling raw meat, particularly poultry
• Thoroughly cooking meat and seafood to avoid contamination
• Promoting public awareness of food and water safety
• Avoiding raw (unpasteurised) milk
• Drinking water only from clean, trusted sources

These combined efforts are vital in preventing the spread of Campylobacter and safeguarding public health.

Summary

Campylobacter-contaminated water can be fatal if left untreated. Children, the elderly, and immunocompromised individuals are particularly vulnerable, and infection can lead to serious complications or death. To prevent this, it is essential to implement effective prevention strategies. Key prevention methods include maintaining good hygiene, consuming clean water, and ensuring that water sources are properly maintained and free from contamination. Additionally, raising awareness within the community and among government authorities is crucial for preventing outbreaks and protecting public health.