SYDNEY, Australia -- Australians love to bet, and if the recent fortunes of the listed biotechnology companies Biota Ltd. and Virax Ltd. are any guide, the national pastime has found another outlet -- on the stock exchange.

The share price of Australian flu-cure company Biota Ltd. soared last week following the announcement that the FDA had approved a flu diagnostic kit using Biota's technology. Although investors had known for some time that the Flu Ola kit was being developed by BioStar Inc., of Boulder, Colo., and that FDA approval was likely, Biota's share price still jumped by 14 percent to A$6.35 (US$3.90) Thursday. By the close of business that day, the share price had fallen to A$5.95 -- still a strong increase of A$0.55 for the day -- and by the end of Monday's trading had fallen another A$0.10 to A$5.85.

BioStar, a subsidiary of Thermo BioAnalysis Corp., has combined its diagnostic technology with the anti-flu technology developed by Biota and now licensed to Glaxo Wellcome plc, of London.

The drug developed by Biota and Glaxo, known as Releza, is now awaiting commercial approval by the FDA.

Another stock to skyrocket recently was Virax, following an announcement by the company in mid-November that it had successfully protected four test monkeys against HIV infection with a treatment that used aspects of its technology.

The stock price swung wildly during November, rising to A$1.85, then dropping to A$1 before increasing again to A$1.50. At the close of business on Monday, the price was A$1.35, with no net price movement for the day.

There has also been a query raised about the company's original reports and whether the treatment is useful against SIV (related to HIV and causing AIDS in monkeys) or HIV. A spokeswoman for Virax commented that monkeys can be infected with HIV, although they do not develop AIDS from the infection, and that the treatment cleared the monkeys of HIV. She noted the company announcements had repeatedly stressed that the test results from four monkeys were not statistically significant. *