3.1 Hepatitis, Legionella and Weil's Disease

Chapter 2 covered the classic "drink it" diseases — Cryptosporidium, Giardia, E. coli O157, typhoid and dysentery — all caught by swallowing contaminated water. The National Water Hygiene assessment goes further: water industry workers also meet organisms that enter the body through other doors. Hepatitis viruses travel the faecal-oral route into the liver; Legionella is breathed in as a fine aerosol; Leptospira soaks in through cuts and mucous membranes. This section covers each of these risks and explains why one of them — jaundice, or hepatitis A or E — appears on the EUSR health-screening declaration you sign before registration.

Hepatitis A and hepatitis E

Hepatitis simply means inflammation of the liver. Hepatitis A and hepatitis E are viruses that infect the gut and liver and are shed in very large numbers in faeces. They spread by the faecal-oral route: sewage-contaminated water or food, contaminated hands, and close person-to-person contact. For water workers the exposure happens wherever hands, tools, vehicles or drinking-water containers are contaminated by faecal material — sewer flooding, work near broken drains, or poor welfare facilities on site.

Hepatitis A symptoms listed by the NHS include a high temperature, flu-like tiredness, headache and muscle pains, feeling or being sick, tummy pain, pale grey poo, dark brown pee, itchy skin and jaundice — yellowing of the skin and whites of the eyes, caused by bilirubin building up as the liver struggles. The NHS notes that hepatitis A usually clears up on its own within 3 to 6 months, and advises adults to stay off work for 7 days after symptoms or jaundice appear and to wash hands thoroughly after going to the toilet.

Hepatitis E behaves similarly. In the UK most cases are acquired as a zoonosis — an infection caught from animals — chiefly through undercooked pork and pork products, according to UKHSA guidance. Globally, however, hepatitis E is a classic waterborne disease, spread faecal-orally through sewage-contaminated drinking water, with large outbreaks where sanitation fails. The lesson for the Blue Card: a virus the UK mostly catches from food is still a water-industry risk wherever sewage and potable water systems are worked on side by side.

Why jaundice is on the EUSR screening list

Before training and assessment, every individual must declare whether they have, or have had in the preceding 12 months:

• typhoid
• paratyphoid
• dysentery
• persistent diarrhoea or vomiting
• jaundice or hepatitis A or E
• prolonged unexplained fever

If any of these is declared, written confirmation from a medical practitioner (for example a GP) that the person is illness- and symptom-free is required before EUSR registration. The logic is containment: hepatitis A and E are shed in faeces, so an infected or recently recovered worker could contaminate a potable supply. That is why a worker with hepatitis must be excluded from Restricted Operations — work on or around potable water, including service reservoirs, wells, boreholes, treatment works and the distribution network — until medically cleared. The claim that jaundice is not reportable is false: it is one of the named triggers on the declaration.

Legionella: risk from aerosols, not drinking

Legionella bacteria are common in natural and artificial water systems. They cause legionellosis, an umbrella term covering two illnesses: Legionnaires' disease, a potentially fatal pneumonia, and Pontiac fever, a milder, self-limiting flu-like illness with fever, headache and muscle aches but no pneumonia. The route that matters is inhalation: people are infected by breathing in fine water droplets (aerosols) containing the bacteria — from showers, spray taps, cooling towers, spa pools, hoses and pressure washing. You do not catch Legionnaires' disease by drinking the water, and it does not pass from person to person.

Temperature is the key control, and the HSE bands are worth memorising:

HSE guidance is to store hot water at 60 °C or above, distribute hot water at 50 °C or above, and keep cold water stored and distributed below 20 °C. Stagnation favours growth: dead-legs and dead-ends in pipework and little-used outlets let water warm up and stand still, so infrequently used outlets should be flushed at least weekly and showerheads cleaned and de-scaled regularly.

Water workers meet Legionella risk in storage vessels and around outlets: tanks and hot-water cylinders in site welfare units, showers in depots, little-used washroom taps, and sediment disturbed during maintenance on warm water systems, which can seed aerosols the moment the water is agitated.

There are legal duties here at awareness level: employers must control the risk under the Health and Safety at Work etc. Act 1974, supported by the HSE Approved Code of Practice L8, Legionnaires' disease: the control of legionella bacteria in water systems (fourth edition), which requires a suitable risk assessment, a written scheme of control, a competent responsible person and records of precautions.

Leptospirosis and Weil's disease

Leptospirosis is a bacterial infection carried by animals and excreted in their urine — most commonly rats, but also mice, cattle, pigs and dogs (NHS). The bacteria survive in freshwater, wet soil, sewers, ditches, drains and slow-flowing watercourses. They enter the body through cuts and abrasions and through the mucous membranes of the mouth, nose and eyes — for example when contaminated water is splashed in the face, or through hand-to-mouth contact after handling wet plant. Sewer and water-network workers are a classic at-risk group.

The illness typically starts as a mild flu-like disease — fever, headache, chills and muscle pain — and many cases resolve on their own. But severe leptospirosis, known as Weil's disease, brings jaundice, liver failure, kidney failure and meningitis, and can be fatal. Early antibiotic treatment matters, so any flu-like illness following work in sewers, ditches or rodent-infested chambers must be reported to a doctor promptly — and tell the GP you work in water, because it changes the diagnosis.

Prevention on site is straightforward barrier control: cover cuts and abrasions with waterproof dressings; wear gloves; never eat, drink, smoke or vape with unwashed hands; wash hands and forearms before eating, drinking and smoking; shower after work; and control rodents around chambers, vehicles and stores.

The three risks compared

Scenario

You are supervising a valve-chamber clean-up beside a slow-flowing ditch used by rats; the welfare-unit shower has been unused for six weeks. You brief the team: gloves and waterproof dressings on for the chamber; no eating, drinking or vaping until hands are washed; eye protection against splashes; the shower flushed and run before anyone uses it; and anyone who later feels flu-like must see a GP and mention the water work. One short briefing covers leptospirosis, Legionella and hand-to-mouth transfer in a single pass.

Common candidate traps

• "Legionella is caught by drinking water." No — the infection route is inhalation of aerosols; drinking Legionella-contaminated water is not how Legionnaires' disease is contracted.
• "Weil's disease comes only from clean water." No — it comes from water contaminated with animal urine, especially rat urine; dirty, stagnant and slow-flowing water is the risk.
• "Jaundice is not reportable." Jaundice or hepatitis A/E in the previous 12 months is specifically named on the EUSR declaration and requires written medical confirmation before registration.
• Confusing hepatitis A and E (faecal-oral, water-relevant) with hepatitis B and C (blood-borne, not the water-screening concern).