The emails, which come from a Yahoo email address, claim that the 19-year-old correspondent has found a herbal root that has successfully helped the sick recover from AIDS, and that hospitals have confirmed that patients are no longer HIV positive. The email continues, asking for help in bringing the cure to English-speaking markets.

However, Sophos warns computer users that this is a ruse to steal personal details, and that the fraudsters behind the scam campaign can use such information to steal money from bank accounts and commit identity fraud.

"People who receive this email may believe they are helping the world fight AIDS, as well as potentially make themselves some money from the proceeds of any distribution of a successful cure. However, the scammers are just using another method to try to dupe computer users into divulging sensitive information," said Carole Theriault, senior security consultant for Sophos. "It's particularly sick of the hackers to exploit human illness in their search for innocent computer users to fleece."

This email con-trick is the latest of many 419 scams. These scams are named after the relevant section of the Nigerian penal code where many of the scams originated and are unsolicited emails where the author offers a large amount of money. Once a victim has been drawn in, requests are made from the fraudster for private information which may lead to requests for money, stolen identities, and financial theft.

Other examples of 419 email scams include a message claiming to come from a persecuted widow of the late Nigerian head of state, an associate of the massacred Nepalese royal family, and even an African astronaut stranded on the Mir spacestation.