Published: 2/09/2009 at 12:00 AM
Thailand has taken the unprecedented step of speeding up the manufacturing of vaccines to fight the type-A H1N1 flu pandemic. However, increasing concern over the vaccine's safety and its fast-track process could end up hurting the credibility of the much-awaited vaccine project, as well as the public's hopes of easy access to the domestic preventive tool.
The Government Pharmaceutical Organisation (GPO) earlier this year adopted the Russia-developed live-attenuated technology from the World Health Organisation as it allows a production of 30 times more vaccine doses than the inactivated technology.
The agency also plans to make the first lot of vaccines available by December, according to its original timeline.
Unfortunately, a recent report on mutation of the seed virus used for the vaccine production sent waves of concern among the experts. The incident caused them to wonder if the vaccine manufacturing process being undertaken at a pilot plant in Silpakorn University's faculty of pharmaceutical sciences in Nakhon Pathom province, should continue.
"Virus mutation and genetic changes in various spots have been detected during laboratory testing. Since the product is not heat-resistant, it may fail to protect people when it is sprayed in through the nose," said Thiravat Hemachudha, a virological expert at Chulalongkorn University's faculty of medicine.
The doctor suggested the government switch to using seed virus from China which is believed to be more stable, and renovate another vaccine plant, run by the Department of Livestock, at Pak Chong district in Nakhon Ratchasima. Its production capacity of 86 million flu vaccine doses would be sufficient for all Thai people, while the pilot plant at Nakhon Pathom has a maximum capacity of only 540,000 doses per month.
Other scientists and researchers criticised the low yield rate of the first batch of vaccine viruses. The disappointing result may have stemmed from both defects in the hen eggs imported from Germany and used for virus culture, or a lack of collaboration from partners involved in the project apart from the Public Health Ministry.
Witit Artavatkun, GPO managing director, defended the seed virus. He maintained that it had not changed or mutated into a virulent form.
"We did not see any significant genetic changes in the position that controls virulence of the seed virus," he said.
He disagreed with Dr Thiravat's recommendations. He said the seed virus from China was not certified by the WHO, and its egg-based production technology was not up-to-date. He also argued that it was impossible to convert the animal vaccine plant for the new purpose. The Department of Livestock plans to produce three animal vaccines. It could not stop its work just to allow the H1N1 project to take over.
The GPO has worked closely with both domestic and international partners. The WHO helps supervise every step of the vaccine manufacturing. The UN agency has actually granted the GPO US$4 million to develop a pilot plant from scratch.
According to the original schedule, Mahidol University's faculty of tropical medicine would be responsible for clinical trials set for early this month.
Vaccine development is considered a major scientific undertaking especially when it comes to global pandemic fears. This time the importance of making available a pandemic flu vaccine is higher than ever for both rich and poor nations.
The WHO has regarded the type A (H1N1) influenza as the most prevalent flu strain.
The virus could spread four times faster than other viruses and 40% of the fatalities are young adults in otherwise good health. Up to 30% of people in densely populated countries risk getting infected. Evidence from outbreak sites also shows the virus has rapidly established itself in the areas and become the dominant influenza strain in most parts of the world. The pandemic will persist in the coming months as the virus continues to move through susceptible populations. So far more than 2,185 people around the world have died from the virus since it emerged in April, according to the latest WHO figures. Thailand reported more than a hundred deaths from the type A (H1N1) pandemic.
Until now, the fatality rate of this influenza is still considered quite low. But history teaches us that the situation could take a turn for the worse during the next wave of the pandemic.
Since only a few countries in the world have plants for manufacturing influenza vaccine, and three companies - Glaxo-SmithKline, Sanofi-Pasteur and Novartis - account for most of the world's manufacturing capacity, the inconvenient truth is that the vaccine amount would not be nearly enough for everyone in the world.
WHO's director-general Margaret Chan said the world's production capacity would be only at 900 million doses a year compared to a global population of 6.8 billion.
Despite the hindrances, Thailand's efforts to make available domestic antiviral stockpiling and producing potentially life-saving vaccines should be applauded rather than booed.
For the first time the country will be able to successfully develop one of the key interventions for reducing local flu infections and deaths without solely relying on imported products. The government's support for the project also brings hope to the possibility of developing a sustainable system of healthcare and scientific research long neglected by previous policy-makers.
Dr Chan even said that political leadership is among the most important things in the battle against the virus.
Surely the safety and effectiveness of the vaccine cannot be compromised. At this point, both good governance and sincere effort from every stakeholder is much needed in seeking ways to overcome the obstacles and challenges of the vaccine manufacturing process. Cooperation is key to ensuring our national health security, that Thailand will be equipped with sufficient "weapons" to combat the virus and that the pandemic will not take too high a toll on the population.
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