Sept. 18 (Bloomberg) -- Australia will begin immunizing people against swine flu in 12 days, heralding a global health campaign that will test public interest in the inoculation.

The nationwide program will start Sept. 30 after regulators approved CSL Ltd.’s pandemic vaccine, Health Minister Nicola Roxon said today. More than 4 million doses are in major cities ready for delivery to hospitals and medical clinics next week.

Speedier-than-expected delivery of the vaccine is providing health authorities a better chance of controlling the first pandemic in 41 years and raising hopes of protecting almost half the world’s population. The first challenge facing governments will be to convince the highest priority people, including pregnant women, asthmatics and health-care workers, that getting the shot is safer than risking infection.

“Australia will be one of the first countries providing vaccine to its population,” Roxon told reporters in the national capital, Canberra. The vaccine “is our best defense against the pandemic flu. While we emphasize the virus has been mild for most people, it has had severe effects on some.”

The fast-moving pandemic has spread to 177 countries in four months, yet causes little more than a fever and a cough in all but a select few. China may start vaccinating its troops at the end of the month, and the U.S. plans to start a nationwide campaign in early October. Australia’s schedule may make it the first country to start.

‘Watching Eagerly’

“The rest of the world will be watching eagerly,” said Jody Lanard, a physician and risk-communication consultant in Princeton, New Jersey.

Results of initial tests found one dose of vaccine to be effective in protecting healthy adults against the pandemic strain within 8 to 10 days. The success with a single shot, instead of the two shots that scientists previously thought would be needed, may effectively double anticipated stockpiles of the vaccine and make more shots available in developing countries, said Nancy Cox, director for the flu division of the U.S. Centers for Disease Control and Prevention.

North America, North Asia, the U.K. and the rest of Europe are racing to have a vaccine ready as the Northern Hemisphere weather turns drier and colder, which prompts people to gather indoors and fans the propagation of the virus. Australia’s flu season peaked about two months ago.

Some people question the need to get vaccinated because the new H1N1 strain so far hasn’t been severe. The virus has killed at least 3,205 people since it was discovered in late April, according to the WHO, which estimates as many as 500,000 people die every year because of seasonal flu. In New Zealand, researchers found that about 1 in 20,000 cases were fatal.

‘Real Worry’

“This is the biggest mass vaccination we have done in world history and we are doing it on data so far which shows this virus is not a lot worse than seasonal influenza,” said Peter Collignon, director of infectious diseases at the Australian National University’s medical school. “There is a real worry that the fear makes us do things out of proportion to the risk.”

“If this was causing 1 or 2 percent mortality and spreading quickly, I would be the first person up there with my arm,” Collignon said. As it is, “I will put my arm up next February or March when I have seen more data.”

Underlying conditions that can intensify the effects of flu include respiratory illnesses, especially asthma, cardiovascular disease, diabetes, a suppressed immune system, and even pregnancy. About 25 percent to 50 percent of severe cases worldwide involve healthy young and middle-aged people, according to the WHO.

A$100 Million Program

Australia ordered 21 million doses of vaccine from Melbourne-based CSL for a program that will cost at least A$100 million ($87 million), Roxon said. Health-care workers in day- to-day contact with patients and vulnerable groups who may experience complications from H1N1 will be targeted first, she said.

Health-care workers, who make up 1 percent to 2 percent of the global population, should get the vaccine first, according the Geneva-based WHO. More than half of health-care workers surveyed in Hong Kong last month said they would refuse the shot after drugmakers expedited tests. A poll shows a third of U.K. nurses would do the same.

“Nobody wants to be a guinea pig,” said Steve Hambleton, vice president of the Australian Medical Association and a general practitioner in Brisbane. “They want to be given scientific evidence to say it’s safe and effective before they volunteer to use it.”

The Atlanta-based CDC is creating video and print advertisements for buses and Web sites including YouTube, Facebook and Twitter, to teach people about the safety of the vaccine and the risks of infection.

Preliminary data indicated that the vaccines are safe, Kathleen Sebelius, U.S. health and human services secretary, told U.S. lawmakers earlier this week. The vaccines are being made by the same methods used for the production of seasonal flu vaccines administered every year.

“You can’t win by either rushing or stalling,” said Marie-Paule Kieny, director of the Initiative for Vaccine Research at the World Health Organization in Geneva. “It will be key to ensure both safety and effectiveness.”

To contact the reporters on this story: Simeon Bennett in Singapore at sbennett9@bloomberg.net; Robert Fenner in Melbourne at rfenner@bloomberg.net.

Last Updated: September 18, 2009 01:52 EDT