What is Leptospirosis?

Mild Leptospirosis - the patient experiences muscle pains, chills and possibly a headache. 90% of cases are of this type. Severe Leptospirosis - can be life-threatening.

There is a risk of organ failure and internal hemorrhaging. This occurs when the bacterium infects the kidneys, liver and other major organs. Experts are not sure why some patients develop the severe form - people who are already very ill, such as those with pneumonia, young children under five, and elderly individuals are more likely to suffer from severe Leptospirosis.

Where does Leptospirosis occur? As mentioned above, leptospirosis is more common in the tropics, but may also occur in the poor parts of large cities in developing nations that are not in tropical areas. When cases do occur, they tend to be sporadic.

Leptospirosis exists globally, but is more common in tropical and subtropical parts of the world. The bacterium thrives in hot and humid environments. The following areas and/or countries/continents are known to have the highest incidences of leptospirosis: Africa, India, China, Central America, Brazil, Caribbean, South East Asia, and Southern Russia.

Cases of infection are also reported in the following tourist hotspots: New Zealand, Australia, Hawaii, and Barbados. After flooding, large outbreaks of leptospirosis may occur. According to WHO (World Health Organization), approximately 10 million people are thought to come down with leptospirosis annually.

Death rates are hard to calculate, because they tend to occur in parts of the world with very basic public health services which do not routinely report many causes of deaths. Climate change, including more cases of flooding around the world, probably means that leptospirosis incidence globally will increase. WHO believes the leptospirosis death rate may be between 5% to 25% of infected patients.

This does not mean that an infected person with access to proper healthcare has a similar risk of dying. In 1995, leptospirosis ceased being a notifiable disease in the USA, so nobody really knows what the true incidence numbers there might be. In 2009, in England, according to health authorities, there were 33 reported cases, of which 14 were acquired while the patients were abroad.

In 2009 in France there were 209 cases.