Coronavirus (Covid-19)Thailand

Sinovac and AstraZeneca: The 2 primary Covid-19 vaccines in Thailand

Photo via Facebook/ อนุทิน ชาญวีรกูล (Public Health Minister)

Since Thailand started its mass Covid-19 immunisation campaign in late February, the Chinese-made Sinovac vaccine and the AstraZeneca vaccine, made in partnership with the UK’s Oxford University, have been used to vaccinate residents in Thailand.

The local firm Siam Bioscience is now producing the AstraZeneca vaccine and the first Thai-made batch is expected to be rolled out next month.

Type of vaccine

AstraZeneca: A recombinant vaccine from a modified chimpanzee adenovirus.

This is a harmless, weakened adenovirus that usually causes the common cold in chimpanzees. The adenovirus vaccine vector, known as ChAdOx1, was chosen as a suitable vaccine technology for a SARS-CoV-2 vaccine as it has been shown to generate a strong immune response from one dose in other vaccines. It has been genetically changed so that it is impossible for it to grow in humans. – Australian Department of Health

Sinovac: An “inactivated” vaccine, using inactivated virus particles to produce an immune response, a traditional approach for vaccines and the same technology used to produce the flu and polio vaccines.

The World Health Organisation says the vaccine is made by inactivating or killing the virus using chemicals, heat or radiation.


Studies are still underway for both vaccines, while more studies of the AstraZeneca vaccine have been completed and reported. In Thailand, a recent study by Chulalongkorn’s Centre for Excellence in Clinical Virology of the Faculty of Medicine found both vaccines effective after both doses.

According to the university study…

  • 99.49% of Sinovac recipients developed antibody reponses 4 weeks after their second injection.
  • 97.26% of AstraZeneca recipients developed antibody responses 4 weeks after their first injection.

Thailand initially used the Sinovac vaccine for people ages 18 to 59 due to limited research for the 60 and up age group. Thai health officials recently announced that recent studies show the Sinovac is safe and effective for adults over 60 years old who are in good health.

Global travel

A dilemma for many expats living overseas, or those wanting to travel in the future, is which Covid-19 vaccine to get as some are not recoginsed by other countries.

Both Sinovac and AstraZeneca have met the World Health Organisation’s criteria for safety and efficacy. The Sinovac vaccine is awaiting final approval.

Some countries may not recognise certain vaccine passports, although international tourism is still in the early stages and proposed regulations are constantly changing.

Thailand recoginses vaccines that are either approved by the World Health Organisation or by the Thai government.

The European Union plans to reopen tourism to American travellers, but they may need to have a vaccine approved by the European Medicines Agency.

Sinovac and AstraZeneca: The 2 primary Covid-19 vaccines in Thailand | News by ThaigerSinovac and AstraZeneca: The 2 primary Covid-19 vaccines in Thailand | News by ThaigerSOURCES: WHO | Healthline

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Tanutam Thawan

Local Thai journalist speaking fluent Thai and English. Tanutam studied in Khon Kaen before attending Bangkok’s Chulalongkhorn University.


  1. Not surprisingly this military sort-of-government has chosen the most questionable vaccines.
    They probably got the best bribes from manufacturers struggling to sell their stuff !!!

  2. “Both Sinovac and AstraZeneca have met the World Health Organisation’s critieria for safety and efficacy.”


    Astra Xeneca met the required standards and was approved for emergency use on 15 February, but SINOVAC HAS NOT BEEN APPROVED BY THE WHO.

    Sinopharm has, but NOT Sinovac – totally different vaccines, produced by completely different companies.

    Sinovac has been waiting for WHO approval since 7 March, but approval has NOT been given yet.

    Un-B-frigging-lievable that you’d confuse Sinovac and Sinopharm and say that Sinovac has “met the World Health Organisation’s critieria for safety and efficacy” when it hasn’t.

  3. Un-B-frigging-lievable that nothing is said on efficiency against variants, sinovac has only 10 % efficiency on some of the variant that are in thailand, in 3 month, the headlines will be, “thai get infected by covid indian variant despite having a sinovac shot !” and all the effort will have been for nothing, why no one address that problem

  4. “Astra Xeneca met the required standards and was approved for emergency use on 15 February, but SINOVAC HAS NOT BEEN APPROVED BY THE WHO.

    Sinopharm has, but NOT Sinovac – totally different vaccines, produced by completely different companies.

    Sinovac has been waiting for WHO approval since 7 March, but approval has NOT been given yet.

    Un-B-frigging-lievable that you’d confuse Sinovac and Sinopharm and say that Sinovac has “met the World Health Organisation’s critieria for safety and efficacy” when it hasn’t.”

    Totally agree

  5. Astra Zeneca is full of problems, In Canada we are moving away from it. Too many side effects like blood clots. As for Sinovac, it is also a shitty vaccine. Thai government is probably being bribed by the Chinese and they are misinforming the Thai people. Pfyzer and Moderna are the way to go.

  6. “Boycott Sinovac people of Thailand.”

    The feeling I get is that it’s being deliberately “used up” on those least likely to object – prison inmates, Klong Toey and other slums, “front line” personnel, and tourist “sandboxes” … maybe even farangs ?.

    “Wait till private hospitals have the Astra and moderna lots of rich Thais in Krung Thep will pay for it £200 a go I reckon”

    Actually less than £75 / $100 for both doses of Moderna, while the AZ’s free as long as it can finally be produced. I think that given the chance a lot of the tourist industry would pay for it for their employees as well, to get things going quickly, and if they had 20 million doses rather than just 6 million they’d all be sold in quick time.

    Job jobbed, problem solved, but it’s not going to happen.

  7. “… the headlines will be, “thai get infected by covid indian variant despite having a sinovac shot !” and all the effort will have been for nothing, why no one address that problem”.

    I raised it elsewhere, @murika, as it’s already happening in the Seychelles but with Sinopharm which is a better vaccine (the one approved by the WHO, unlike Sinovac).

    37% of the new / active cases, and 20% of the cases serious enough to be hospitalised there, have had BOTH doses.

    I was told I was imagining it, although it’s from the Health Minister and on all the major news sites this week (France 24, DW, Al Jazeera, Reuters, CNN, BBC, Aus, etc, etc) but apparently no-one else noticed.

  8. There are medical personal and government ministers in China who are using any and every excuse NOT to be jabbed with the Sinovac doses… you would need to be INSANE to consider getting that one after multiple reports, this one in the WSJ for example, 67% effectiveness really isn’t gonna cut it especially for heavily populated areas

  9. Leaked documents from provincial and municipal governments in China reveal a slew of previously unreported severe adverse events related to COVID-19 vaccines made and administered in China. Tellingly, one of the documents listing the reactions came with an admonishment to not share that news with the public, according to a report in The Epoch Times.

    The revelation came just days before the World Health Organization (WHO)’s planned April 26 review of the Sinovac COVID-19 vaccine for emergency use.

    One document noted that “suspected group vaccination adverse reactions (include) death, and severe disability of the recipients.” That appeared in the “Notice of Further Strengthening the Safety Management of COVID-19 Vaccination,” issued April 6 by the Leadership Team for Epidemic Response within the Hebei provincial government.

    That document was marked, “extra urgent, and non-disclosure to the public.” It required agencies to “strengthen the monitoring and handling of the adverse reactions that would have a major negative impact on society,” The Epoch Times reported, showing a Chinese-language photo of the report.

    A second report documented rashes, fever, nausea, diarrhea, chest tightness and shortness of breath resulting from Chinese COVID-19 vaccinations. It was entitled “Statistical Table of Adverse Reactions of COVID-19 Vaccines,” and listed adverse events from Laishui Community Health Service Center of Laishui County at Baoding City, also in Hebei province. It was issued April 8.

    A third document detailed the 47-day (and counting) quarantine of an individual who was fully vaccinated yet continued to test positive for the virus. Called the “Request for Consultation with Provincial Experts on a Resident Surnamed Sui,” the document was issued March 3 by the office of the Baoding municipal Leadership Team for Response to the Epidemic.

    As it details, Sui, a resident of the Lianchi District of the city of Baoding, received two doses of a Chinese-made COVID-19 vaccine in December 2020, then traveled to Germany. Upon return, he was quarantined at a centralized quarantine site. During quarantine, Sui took five comprehensive tests, including CT, blood serum, nucleic acid and routine blood tests. IgM antibodies, which denote a recent infection, were found in the blood serum tests each time. At the time of the report, per China policy, Sui was still quarantined and waiting for a negative test.

    According to The Epoch Times, Chinese experts consulting on Sui’s case suggest that the positive results for IgM may be a side effect of the vaccination. The reason, they said, is that some individuals may test positive for half a year. Others given the same vaccine may test negative. The difference depends upon their physical condition.

    Given Sui’s case, other adverse events in municipal and provincial reports within China, and reports throughout the world regarding adverse events, the safety of the Sinovac and Sinopharm vaccines is concerning.

    Earlier in the year, Tao Lina. M.D., a Shanghai vaccine expert, posted the physician manual for the vaccine, listing 73 adverse events associated with the Chinese vaccine. He called it the “most unsafe vaccine in the world.” He retracted his statements a few days later.

    China’s COVID-19 vaccines have been distributed to at least 50 nations, and the list is growing. As they roll out, various countries are compiling their own lists of mostly minor side effects. For example, CNN Philippines reported that the most common adverse events associated with Sinovac’s COVID-19 vaccine are elevated blood pressure, headache, injection site pain, dizziness and rash. Egypt reported similarly minor side effects. Pakistan likewise reported no adverse side effects.

    Since the Sinovac COVID-19 vaccine rollout, the vaccine also has been plagued by disparate efficacy claims. As Reuters reported, Brazil claimed the Sinovac vaccine is 50.7% effective, just over the 50% mark required by the World Health Organization and well below the 78% efficacy rate touted when the vaccine was announced in China last January.

    A real-world study from Chile announced by the Ministry of Health in a news conference April 16, boosts efficacy rates to 67% in terms of preventing symptomatic infection, 85% at preventing hospitalizations, 89% at preventing admission to the intensive care unit and 80% at preventing death. That report, however, did not specifically assess the vaccine against any of the emerging variants.

    The Global Times (the English edition of People’s Daily – the official publication of the Chinese Communist Party’s Central Committee), in late April claimed an adverse event rate of 1.06% among the more than 519,000 people inoculated by December 1, 2020. That was far lower than the 13% and 19% rates reported in Phase II trials.

    Gao Fu, director of China’s Center for Disease Control and Prevention, admitted the low efficacy rates of China’s vaccines in a surprising statement at China’s National Vaccine and Health Conference April 10. Consequently, he said, “It’s now under consideration whether we should use different vaccines from different technical lines for the immunization process.” A few days later, he walked back his comments, saying they were misunderstood and actually applied to vaccines globally.

    So far, China has administered 216.08 million COVID-19 vaccines, according to data released by the National Health Commission April 24, 2021.

  10. 1 comment from BETTER known and better respected news media stating about the 67% effectiveness of the sinovac jab and one large copy and paste from biospace . com about the 73 adverse effects in both China and Chile and yet the Thaiger deems to find them breaking some sort of rules and doesn’t publish??

  11. Indonesia tracked 128,290 health workers in Jakarta from January to March and found that the Sinovac vaccine protected 98% of them from death and 96% from hospitalization as soon as seven days after the second dose.

    So you might have more chance of catching Covid than you would with other vaccines but it’s not going to kill you or make you seriously ill, seems ok to me.

  12. In case there is still any doubt, the WHO has NOT said that Sinovac has “met the World Health Organisation’s criteria for safety and efficacy.”

    They DID say on 30 April that approval was “pending” and if approved an announcement would be made by 14 May. It is now 19 May.

  13. “… seems ok to me.”

    You’re evidently either very easily satisfied, very naive, or very stupid, or you have some other agenda, @London AI.

    Your cherry-picked stat is meaningless as it gives no information about age (although obviously as “health workers” all were under 65 and most were probably young), health (although probably more healthy than average) or any other factors and there was no control group.

    If you picked a similar-sized group of unvaccinated migrant workers from Samut Sakhon infected with Covid, for example, you could claim that after drinking tap water 100% were protected from death and 100% from hospitalization – it would be true, but it would be crap.



    I wouldn’t go so far as to suggest that Sinovac is “going to kill you or make you seriously ill”, but YOUR STAT OF 2% DEAD AND 4% HOSPITALISED IN TWO MONTHS DOES JUST THAT.

  14. Actually, the article DID NOT confuse Sinovac and Sinopharm as many commenters above seem to suggest. The article clearly states that Sinovac meets the WHO *criteria* for safety and efficacy but has not received final approval. The WHO wouldn’t be considering it for final approval if it didn’t meet the criteria.

    In the WHO’s own words (CoronaVac is another name for Sinovac):
    “We are very confident that 2 doses of CoronaVac are efficacious in preventing PCR confirmed COVID19 in adults (18-59 years)”
    “We are moderately confident that the risk of serious adverse events following one or two doses of CoronaVac in adults (18-59 years) is low”

    So the question is not whether it meets the criteria the WHO laid out, only whether the WHO will approve the specific existing studies confirming it or request more data.

  15. “The WHO wouldn’t be considering it for final approval if it didn’t meet the criteria.”

    Links are not allowed here, @Larry, but that’s completely untrue.

    The reality is that the WHO wouldn’t be considering it for final approval if THE EVIDENCE THEY WERE GIVEN didn’t meet the criteria.

    The two are completely different.

    While your cherry-picked quotes are what the WHO said, you’ve completely ignored the final page of your own link which make it unavoidably clear that the WHO are NOT happy with the “Quality of Evidence” shown them.

    Of the six criteria required, the evidence for one has a “high level of confidence”, three a “moderate level of confidence” and two a “low level of confidence”.

    So the question is absolutely “whether it meets the criteria the WHO laid out” since the WHO has a “low level of confidence” that in two of the six required areas it does, despite the evidence presented.

    It doesn’t get much lower than a “low level of confidence”.

  16. @Simon thanks for your response. I’m not sure who is cherry picking since you have said pretty much exactly what I wrote. As I wrote, the existing evidence meets the WHO criteria, but the WHO still needs to review that evidence and decide whether they are confident enough in it as-is, or will request more data before final approval.

    Furthermore, it is also worth pointing out that the “low levels of confidence” you mentioned wasn’t in “six required areas”. The word “required” doesn’t appear. It uses the words “key areas to inform policy recommendations”. The low level of confidence were in specific populations (older populations in one case, and people with specific comorbidities in the other). As such, the WHO may very well approve it for most people and withhold approval for those populations. Few of the vaccines have been approved for children for exactly this reason. They only approve in cases where the studies have a sizable enough number of those people. It doesn’t mean that there was anything wrong with those studies for the general population.

    What the evidence says (it meets the criteria in adults) and what level of confidence we have in that evidence across all populations are two different things. I only wrote that the Thaiger article was not misleading in saying that the evidence meets the safety and efficacy criteria in adults but the WHO is still reviewing the evidence for specific final approval. (I.e. The Thaiger didn’t confuse Sinovac and Sinopharm.)

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