Thailand found one confirmed case of vaccine-induced thrombosis and thrombocytopenia (VITT) caused by the AstraZeneca shot, after more than 15 million doses have been administered, the Ministry of Public Health said on Wednesday.
There was also one confirmed case of heart inflammation linked to the Pfizer jab, they said.
“There was only one confirmed VITT case and the person has recovered,” said Dr Chakkarat Pittayawong-anont, the director of the epidemiology division at the Department of Disease Control (DDC). “The patient was the only person that fits four to five of the diagnostic criteria.”
“There are other suspected VITT cases but they do not fit four to five of the categories,” he said.
Chakkarat said the confirmed case and suspected ones consisted of two males and three females age between 26-76. Of the four probable cases, one has recovered and three have died, he said. All five cases happened after their first dose.
Combined thrombosis and thrombocytopenia include both blood clots as well as low levels of blood platelets. Studies on the precise statistics are ongoing, but scientists agree that getting any vaccine available is much safer than not getting any protection from the pandemic.
Out of 15.43 million AstraZeneca doses that were administered as of September 5:
- 5.14 million were given to people aged between 21-40 which resulted in three probable VITT cases
- 5.74 million were between 41-60 which resulted in one probable VITT case
- 4.55 million were between 61-80 which resulted in one probable VITT case.
The overall incidence of probably and confirmed symptoms were “accounted for 0.03 per 100,000 doses that have been vaccinated,” Chakkarat said.
“The symptoms happened the fastest at three days after vaccination and longest was 15 days after vaccination,” Chakkarat said.
“The majority of the five VITT cases happened to young people which was similar to VITT cases abroad where Europe, Canada and Australia have reported around 0.73 per 100,000 people that have received the first dose of AstraZeneca vaccine,” he said.
The probability of VITT was higher in the United Kingdom with one case out of 100,000 doses for people age 50 and above and two cases out of 100,000 doses for people aged less than 50, he said.
“This means that the chance of VITT cases happening in Thailand is very low,” he said.
“When compared to the benefits from being vaccinated against Covid, where around two hundred people are dying from it every day, to the number of probable VITT cases, we still recommended people to get vaccinated with AstraZeneca because the benefits are higher,” he said.
VITT symptoms include severe headache, weak arms and legs, distorted mouth or face, chest pain, difficulty in breathing, swollen and painful feet, severe stomach ache or petichial haemorrhage (small red dots under the skin that is no larger than one centimetre) four to 30 days after being vaccinated by AstraZeneca.
“There will be no fever and if you found these red dots after being vaccinated, you should seek medical attention to find out what they are related to and do not forget to bring your vaccination document,” he said.
International attention has focused on a possible link between the condition and the vaccine against Covid-19 produced by Anglo-Swedish company AstraZeneca.
A Danish study in April found the risk of thrombosis approximately doubled following the AstraZeneca vaccination for patients in their 40s, but said the results on thrombocytopenia could have been just reflecting the increased surveillance.
Other studies have found background levels of thrombosis with thrombocytopenia to be high even in the absence of vaccination. All medical opinions concur that foregoing vaccination increases the risk of dying from Covid much more than any risk from getting the jab.
For the heart inflammation case related to Pfizer, the patient was an overweight 13-year-old male which had the symptoms two days after being vaccinated by the mRNA vaccine.
“The patient suffered from severe chest pain…and he had recovered because he was treated in time and based on overseas studies, such side effects from Pfizer usually happened to young males which is something that we are keeping an eye on,” Chakkarat said.
“People who used to have suffered from heart inflammation or heart failure before should tell the doctor before being vaccinated with Pfizer or Moderna as they are both mRNA vaccines,” he said.
Thailand has ordered 61 million AstraZeneca doses and 30 million Pfizer doses that are expected to arrive within 2021 and the latter are the only vaccine that is being given to minors age between 12 and 18 so far.