Mail and Guardian, 4 October 2002, HIV And Lemons: Sour But Safe, Tom Learmont
A scientist has proved that lemon juice kills the HIV virus on contact.
After investigating traditional contraceptive techniques, an eminent Australian-based scientist has proved that lemon juice diluted five to one with water kills HIV and sperm within seconds.
Roger Short's findings will be made public in a scientific paper read at The Ninth International Symposium on Spermatology at the University of the Western Cape next week.
Symposium convener Professor Gerhard van der Horst is excited by the discovery of a cheap, universally available, non-technical way to block HIV transmission, and describes Short's paper as "a milestone".
A woman whose husband insists on "nyama to nyama" can protect herself against HIV transmission with a small sponge and watered-down lemon juice, perhaps leaving him none the wiser. Men may also anoint themselves with the acidic juice to prevent transmission.
The abstract of the paper says: "Historically, lemon juice on a sponge, or half a lemon placed over the cervix, was widely used as an effective contraceptive. We have shown that 20% lemon juice (final concentration) in human semen irreversibly immobilises 100% of sperm in less than 30 seconds. A similar concentration also rapidly inactivates HIV. Thus intra-vaginal lemon juice might provide a cheap, readily available and extremely effective way of stopping the sexual transmission of HIV, whilst also providing contraception."
The paper refers to additional strategies, including circumcision for men, which more than halves the risk of HIV infection. The virus appears to enter the penis via specific HIV-receptive Langerhans cells on the inner surface of the foreskin. The vagina has its own Langerhans cells that are also the main entry point for HIV in women.
Thickening the vaginal epithelium by oestrogen administration could provide cheap, safe and effective HIV protection for women, but drug firms are not interested, says Short.
Based at the University of Melbourne, Short is also professor-at-large at Cornell University in the United States, and a visiting fellow of Green College, Oxford. His career began in England at Cambridge in 1956. He was co-editor and principal author of the eight-volume Reproduction in Mammals published by Cambridge University Press from 1972 onward, which was translated into six languages.
The lemon juice breakthrough is not the first scientific bombshell he has lobbed. He was part of the Cambridge University team that crossed a camel with a llama in Dubai. He also co-authored a physiological study presenting strong evidence that the elephant was an aquatic mammal in an earlier evolutionary phase. He has published more than 300 scientific papers and, with Dr Malcolm Potts, wrote a bestseller aimed at the layman: Ever Since Adam and Eve: The Evolution of Human Sexuality (1999).
After researching circadian rhythms in mammals, Short took out US and European Union patents on the use of the chemical messenger melatonin to counteract the adverse effects of air and space travel. Melatonin has been tested aboard the Russian space station Mir, and is recommended to all Nasa astronauts. The patents are licensed to US drug giant Eli Lilly at present, through the Australian company Circadian Technologies.
Short's interest in the transmission of HIV infection arose naturally from his research activities of the past 20 years, which focused on contraception, the evolution of human reproduction and the causes of the Earth's overpopulation.