Credit: AstraZeneca

Thailand sets to resume AstraZeneca vaccine roll-out as no link of blood clots weighed in

WHO has said there has been no relationship between the vaccine and the reported blood clots problem established so far, and the vaccine administering should be continued while an investigation into the reported cases is ongoing

Dr. Opas Karnkawinphong, the Disease Control Department’s Director General, said during the press briefing today that the department has learned more that blood clots development after AstraZeneca vaccine administration in some recipients in Europe is unlikely caused by the vaccine itself.

The Public Health Ministry is gathering all information relevant to the reported cases from the World Health Organization (WHO) as well as other concerned organisations and would possibly be able to conclude by next week.

If it is confirmed that the vaccine has nothing to do with the reported blood clots problem, the vaccine administration would immediately be resumed as planned.

“But we insist that Covid-19 vaccination among Thai people must be, first and foremost, safe,” said Dr. Opas.

Thailand planned to administer the AstraZeneca vaccine on Friday, with Prime Minister Gen Prayut Chan-o-cha being the first to receive the vaccine to boost public confidence. However, the plan was abruptly suspended after the ministry had received reports of blood clots development in Europe, with one latest death in Denmark.

The governments’ top medical advisors, including former Public Health Minister Dr. Piyasakol Sakolsatayadorn, now an adviser of the government’s Covid-19 vaccine administration committee, called on an immediate press conference to clarify the issue, citing the delay of AstraZeneca inoculation was needed to ensure safety.

Dr.Piyasakol said the senior advisors had consulted one another and agreed that the administration of the vaccine should be delayed in order to wait for the results of an investigation into the reported cases in Europe. This is to ensure that Covid-19 vaccination among Thai people is safest.

“If it turns out that the vaccine has nothing to do with blood clots, that would even give us confidence that we will receive the safest vaccination treatment. So, trust us that we are delivering the best to people,” said Dr. Piyasakol.

Public Health Minister and Deputy PM Anutin Charnvirakul said the minister paid heed to the senior advisors. Thailand is not in a hurry to receive Covid-19 vaccines as it has managed to put the spread of the virus under control. It’s therefore appropriate to wait for clear answers about the blood clots problem before going ahead with the vaccination plan on this vaccine, he said.

Thailand’s Covid-19 vaccine administration started on February 28 after the first batch of China’s Sinovac vaccine, 200,000 doses, as well as over 100,000 more from AstraZeneca had arrived and been certified here.

Under the government’s plan, up to 2 million doses of the Sinovac vaccine are expected by April, while 61 million doses of the AstraZeneca vaccine are expected to be produced and distributed here by the company’s endorsed Siam Bioscience.

According to the latest vaccine administration plan, the total of 63 million doses of the vaccines are set for 31.5 million people by this year. Up to 10 million people could have received the vaccines each month, starting from June, according to Dr. Opas.

So far, the Sinovac vaccine has been administered to the target groups, especially those working on the front line, in 13 provinces since February 28. Up to 44, 409 people have received the first shot of vaccines already, with seven provinces having completed their vaccination plans.

Bangkok and Samut Sakhon province, the epicenter of the outbreak this round, will complete their tasks by next week, Dr. Opas said.

Senior medical advisors of the government lined up to explain the situation on Friday.
Credit: Public Health Ministry

Blood clots concerns

WHO on Friday also stepped out to allay fears of a link between the blood clots problem and the AstraZenaca vaccine, saying the relationship between the two has not been shown so far.

According to UN News, WHO has assigned its global advisory board to investigate into the reported cases and the findings will be made public once they are available.

The BBC has reported that there have been about 30 cases in Europe that have had blood clots developing or “thrombo-embolic events” after the AstraZeneca vaccine was administered. These have prompted some countries to hold their vaccine administration plans against the vaccine as a precaution. They include Austria, Denmark, Estonia, Lithuania, Norway, Iceland, and Thailand, according to WHO.

But WHO said the plans should be continued while the investigation is ongoing.

“Blood clotting episodes are common in people “so it’s not clear if this was something that was going to happen”, or whether the vaccine was responsible”, said Dr. Margaret Harris, the WHO spokesperson.

“A causal relationship ….has not been shown. The panel had taken the position that the jab should continue to be administered, while an investigation of cases of these thrombo-embolic events is ongoing.”

Dr. Harris also cited that the European Union medical agencies’ risk assessment committee, Pharmacovigilance, had also decided that the vaccine’s benefits “continue to outweigh the risks”.

As of March 9, WHO learned that there have been over 268 million doses of vaccines delivered since the start of the pandemic, and based on data reported to WHO by national governments, no causes of death have been found or been caused by Covid-19 vaccines to date.

According to the WHO Covid-19 vaccine tracker, there are 81 vaccines in clinical development and more than 180 in the pre-clinical development phase.

WHO has approved two vaccines for emergency use against Covid-19; the Pfizer/ BioNTech vaccine (approved on December 31, 2020), and two versions of the AstraZeneca/ Oxford vaccine (approved on February 15).

The Chinese Sinovac is currently in the last stage of clinical evaluation and may be approved for use by the end of the month, the WHO spokesperson pointed.

Later on Friday, WHO also announced it had given clearance to the vaccine developed by Janssen (Johnson & Johnson) for emergency use in all countries, and for the international UN-partnered effort to roll-out vaccines equitably across the world, COVAX.

The vaccine from Janssen is the first to be listed by WHO as a single dose shot, which should facilitate vaccination logistics in all countries, the organisation said.

As of Friday, there have been over 118 million confirmed Covid-19 infection cases, including 2.62 million deaths. The highest number of cases of confirmed infection continues to be in the Americas (52. 38 millions), followed by Europe (40. 43 millions), South-East Asia (13.81 millions), Eastern Mediterranean (6.79 millions), Africa (2.92 millions), and Western Pacific (1.69 millions).

For Thailand, it has seen 26, 757 cumulative cases today, with 78 new confirmed cases, and 86 deaths.

Credit: AstraZeneca

Getting to know AstraZeneca vaccine

According to AstraZeneca, the vaccine is licensed for active immunisation to prevent Covid-19 in individuals 18 years and older.

It is currently undergoing final quality control testing, after which it will be handed over so that the local vaccination programme can begin, the company said in its press release during the arrival of the first batch here on February 24.

The vaccine can be easily stored, transported, and handled at normal refrigerated conditions of between two to eight degrees Celsius. It can be held for at least six months and administered within existing healthcare settings, the company noted.

The AstraZeneca vaccine, or formerly AZD 1222, was co-invented by the University of Oxford and its spin-off company, Vaccitech.

It uses a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees and contains the genetic material of the SARS-CoV-2 virus spike protein. After vaccination, the surface spike protein is produced, priming the immune system to attack the virus if it later infects the body, the company explained.

The company claimed that the vaccine has been shown to be safe and effective at preventing symptomatic Covid-19, when taken as two doses administered at a four to 12-week interval. It has been shown to be 100% protective against severe disease, hospitalisation and death, more than 22 days after the first dose is administered.

Now the vaccine has been granted conditional marketing authorisation or emergency use approval in more than 50 countries, with the World Health Organization Emergency Use Listing accelerating the pathway to access in up to 145 countries through the COVAX Facility.

The first batch of the vaccine, 117,600 doses, arrived in Thailand on February 24.

Graphic: How does the Oxford vaccine work
Credit: Nature/ BBC