The WHO has said it could be the end of the year before a vaccine for the H1N1 influenza is properly licensed.
However, countries are being allowed to use emergency provisions to get the medication out faster if they decide the need is there.
Experts say the vaccine will be marketable in the next couple of months, but will need to undergo tests.
“The regulatory authority will certainly want to have a better handle on safety in the clinical trials, the dosing in clinical trials, and these clinical trials will take some time.” said aWHO vaccine expert in Geneva.
Meanwhile, more than 400 schools will be closed for five days in the Thai capital Bangkok, to allow for thorough disinfection.
There have been more than 4000 reported cases of H1N1 in the country, and 24 confirmed deaths.
The Thai government has also placed an order for two million doses of a vaccine, with delivery expected in December.