In light of information regarding the mutations of the H5N1 virus, the Central Institute of Epidemiology has affirmed: “The H5N1 virus has been present for over 2 years, and of course, there must be signs of mutation. However, the A/H5N1 flu vaccine that the world and Vietnam are researching still maintains high efficacy, protecting humans against the current mutations of the H5N1 virus.”
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Professor Nguyen Thu Van, a member of the research team producing the H5N1 vaccine |
After confirming this, Professor Nguyen Thu Van, Director of Vaccine and Biological Products Company No. 1 (under the National Institute of Hygiene and Epidemiology), stated that only when a pandemic occurs, meaning that H5N1 has mutated strongly to transmit from human to human, will the current vaccine being researched lose its effectiveness.
Therefore, while this worst-case scenario has not yet happened, the development of the H5N1 vaccine remains critically necessary.
Vietnamese Vaccine: Affordable and Safe
Historically, global vaccine manufacturers have used traditional technology that involves producing on Specific Pathogen Free (SPF) chicken eggs, which do not carry specific pathogens.
This means that vaccines must be produced in completely sterile facilities. However, the investment cost to build such facilities is substantial, and the price of a SPF chicken egg is also very high.
Vietnam typically imports these “clean” eggs from other countries. However, the eggs imported through intermediaries may no longer guarantee quality, posing risks to those receiving the vaccine.
Moreover, producing vaccines on chicken eggs comes with other limitations, such as a low viral titer (the ability of the virus to replicate and produce antibodies); it takes 2 to 4 eggs to produce a single vaccine dose for humans.
Additionally, despite purification processes, a certain amount of Ovalbumin remains in the eggs, which is one of the causes of allergies and sensitivities in humans. The production time for a batch of flu vaccine on chicken eggs can take up to 4 to 6 months.
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Testing the H5N1 vaccine on monkeys in Quang Ninh |
After considering these challenges, the research team at the Central Institute of Hygiene and Epidemiology opted for a unique approach, aiming from the outset to produce the A/H5N1 flu vaccine using primary monkey kidney cells.
In a suitable environment with good cultivation practices, the viral strain can replicate many times, serving as the “raw material” for vaccine production. The H5N1 virus strain that the institute is studying was isolated from samples of patients infected with avian influenza in a northern province.
With experience in producing vaccines for Hepatitis A and Polio, along with international collaboration, the team implemented the “cell culture” method, which is regarded as the most efficient pathway for vaccine production.
As of now, no country in the world has a licensed H5N1 vaccine. Aside from the United States and Hungary, which have completed preliminary clinical trials, many countries are still in the testing phase or preparing for field trials, including Vietnam.
The estimated cost of the Vietnamese vaccine will be very low, around 30,000 VND per dose.
Regarding the capacity to meet the demand for vaccinations in Vietnam, Professor Van estimates that the institute can only produce 2 to 3 million doses per year, sufficient for about 1 million people.
Who Will Be the First to Test the Vaccine?
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The scientists of the Central Institute of Hygiene and Epidemiology continue their research on the H5N1 vaccine |
In a conversation with VietNamNet at the H5N1 vaccine research area, Professor Nguyen Thu Van happily announced: ”Vietnam has successfully produced 6 batches of H5N1 vaccine for humans. Samples from these 6 trial production batches have been thoroughly tested according to the minimum requirements of the World Health Organization (WHO) and sent to WHO laboratories for evaluation.”
Previously, scientists at the Central Institute of Hygiene and Epidemiology completed the research and production journey of the H5N1 vaccine with animal trials. Once approved by WHO, the institute will conduct clinical trials of this vaccine on a group of volunteer participants.
Professor Van stated: ”The selection of test subjects will be very strict. Since the beginning of the research and production process, those of us directly involved have volunteered to try the vaccine, but there is no guarantee we will be chosen.“
The volunteer group will consist of about 20 to 30 individuals who will not have contact with poultry for 15 days prior to the vaccine trial and will receive 2 to 3 doses over a period of 2 to 3 months. “Of course, we will select very carefully, and will announce this once we receive permission for human trials,” Professor Van communicated.
However, when asked specifically about the volunteers, Professor Van declined to disclose details. “Science is not a joke. Selecting individuals for vaccine trials cannot be taken lightly. Only when we have specific individuals will we make an announcement.”
After the H5N1 vaccine is permitted for circulation, scientists will have many more fascinating stories about the journey of the H5N1 vaccine ”made in Vietnam”.
Le Ha
