How is Weil's disease caught and what happens?

The bacterium enters the body through breaks in the skin (cuts, blisters, abrasions) and via the lining of the nose, throat and alimentary tract. The incubation period for the disease can last anything from 3 - 15 days (though cases over 30 days and under 48 hours have been recorded). In its initial stage, it can be commonly mistaken for influenza as symptoms include:

• Fever, chills, muscular aches and pains
• Loss of appetite and nausea.

The fever can last for around five days followed by a marked deterioration in a small number of cases. The infection becomes more violent in its later stages with further symptoms such as:

• Bruising of the skin
• Sore eyes
• Anaemia
• Nose bleeds
• Jaundice.

Most people will recover completely with treatment, but there are cases where the illness causes serious damage to internal organs and can lead to death. Weil's disease is commonly treated by antibiotics. Recovery from the condition (once the serious stages are passed) can take from 6 to 12 weeks.

Anyone experiencing fever after exposure to high risk water should contact their GP immediately. Always tell your doctor you suspect Weil's disease to avoid misdiagnosis. If you think you have flu and then develop the later symptoms after exposure to water at risk of contamination, go directly to a hospital and tell them you suspect Weil's disease.

Who is at risk from Weil's Disease?

The rats that spread the disease commonly live near water and places where there is easy access to food such as farms and stables. Those at high risk include sewage workers, abattoir workers, farm workers, miners and those who have an increased contact with water such as cavers and water sports enthusiasts. The Leptospira bacteria does not live long in dry conditions but can survive in fresh water for up to a month (in salt water the bacteria only survives for a few hours). If you work (or play) with water that has a high risk of rat infestation take great care not to ingest the water or let any wounds come into contact with it.

Protecting yourself from Leptospira bacteria infection

The most effective way to protect yourself from Weil's disease is to avoid contact with infected water. However, there are steps you can take to lower your risk of infection if you have to come into contact with water in lakes, streams, rivers or sewage works/pipework:

• Wear splash-proof clothing and gloves - those who have to enter the water need to wear oversuits and gloves
• If you have cuts or grazes, cover them in a waterproof dressing and do not allow them to be submerged in the water
• never swallow water unsuitable for drinking
• Do not immerse your head
• As soon as you are out of the water, take a shower in clean water as soon as possible
• Wash all equipment and clothing in clean water
• Clothing that can withstand bleaching should be disinfected to kill the bacteria
• Always use clean fresh water to clean wounds as soon as possible
• If you have to enter water at a high risk of infection it is possible to take Doxycycline as a preventative measure.

It is always prudent to remember that any water course can be infected with any number of harmful organisms, so use your common sense and don't take risks that can lead to exposure.