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Spread of diseases

Solar Water Disinfection

Written by , on May 16, 2008

Water can be disinfected simply by exposing plastic water-filled bottles to the sun. The length of time needed varies with the climate from six hours to two days. The technique is recommended by the World Health Organisation and used by over two million people.  Read more »


Written by , on May 9, 2008

When populations increase and come into contact with other population, they often encounter diseases for which they have no immunity – and the results can be devastating. There are many examples. In 430 BC when the Athenians encountered the Persians in the Peloponnesian Wars, they also encountered typhoid fever which killed a quarter of the […]  Read more »