Apr 15, 2008 (CIDRAP News) – Japan's health ministry today said it was on the verge of approving a plan to administer prepandemic vaccine to healthcare workers, which would make it the world's first country to tap its national stockpile for this purpose.
Kishiko Yamaguchi, an official from Japan's health and welfare ministry, said the plan, which awaits approval tomorrow, would allow the vaccination of about 6,000 quarantine officials and healthcare workers by the end of the year, the Associated Press (AP) reported today.
Japan has already approved and stockpiled pandemic vaccines for 10 million people that are based on H5N1 viruses from China, Indonesia, and Vietnam, according to a report today from Reuters. The health ministry said the vaccines were made by the Research Foundation for Microbial Diseases of Osaka University and the Kitasato Institute, the report said.
In a November 2005 presentation for the World Health Organization (WHO) that summarized clinical study results for Japan's pandemic vaccine, Masato Tashiro, MD, PhD, with the National Institute of Infectious Diseases in Tokyo, revealed that the project is supported by the government, and the same formulation of the alum-adjuvanted whole-virus vaccine is produced by all of the manufacturers.
Yamaguchi told the AP that if initial tests show that the prepandemic vaccine is safe and effective, the ministry would consider vaccinating 10 million more people, including such vital workers as lawmakers, police, and other healthcare workers. Reuters reported that the second vaccination wave would also include those who maintain infrastructure networks such as gas and electricity.
International health officials have been cautious about taking steps toward vaccination in advance of a pandemic, because researchers are uncertain if vaccines that are currently in national stockpiles will offer cross-protection against a future pandemic strain. Also, it's not clear if any adverse events would arise from the use of the vaccine, which makes it difficult to weigh the usefulness of the strategy.
In a May 2007 bulletin, the WHO acknowledged that as prepandemic vaccines become available they could be used in poultry workers, healthcare workers, and whole populations. However, the WHO did not recommend that countries undertake the strategy.
Gregory Hartl, a spokesman for the WHO, told the AP that prepandemic vaccination is "a big roll of the dice" but said the WHO doesn't oppose countries using the vaccines.
The European Centre for Disease Prevention and Control in 2007 praised the development of prepandemic vaccines but said it did not support countries using them until the WHO elevates its pandemic phase to 5 or 6 (from the current phase 3), which would indicate significant human-to-human transmission is occurring.
See also:
May 10, 2007, CIDRAP News story "WHO equivocal on prepandemic use of H5N1 vaccines"
Oct 31, 2007, CIDRAP News story "The Pandemic Vaccine Puzzle: Part 5, What role for prepandemic vaccination?"
Presentation to the WHO on Japan's pandemic vaccine
May 2007 WHO pandemic influenza bulletin