AstraZeneca: What you need to know

James Kon

The Brunei Darussalam Medicines Control Authority (BDMCA) has verified the safety and efficacy of the Oxford-AstraZeneca vaccine, following a stringent scientific assessment process by the National COVID-19 Vaccine Technical Committee.

The authorisation for use in the country has been granted under the Special Approval during Public Health Emergency or Pandemic situation.

In addition to Brunei Darussalam, the AstraZeneca vaccine has also received approval for use by at least 93 other countries including Australia, the United Kingdom, the European Union and Malaysia.

The effectiveness of the AstraZeneca vaccine was studied in a number of international randomised control Phase 3 trials. Based on the findings of these trials, the efficacy of the AstraZeneca vaccine in preventing symptomatic COVID-19 disease, after two doses, ranges from 70 to 90 per cent – more effective than the average flu vaccine.

The reassurance of the effectiveness in the use of AstraZeneca vaccine was made by Ministry of Health (MoH) in response to public concerns of the vaccine, and was published in the recent frequently asked questions (FAQs) pertaining to the opt-in programme for the Oxford-AstraZeneca COVID-19 vaccine.

The ministry also shared that following the temporary hold of the AstraZeneca vaccine announced on April 6, the MoH conducted a review on the safety data and reports of extremely rare events of clotting associated with low platelets (thrombotic thrombocytopenia) in other countries. The review identified no increased risk in older individuals, and a small increase in risk in younger individuals.

Overall, regardless of age, the risk is considered to be extremely low, and in common with other international regulatory authorities such as the World Health Organization (WHO) and the European Medicines Agency (EMA), the benefits of the vaccine outweigh the risks.

The MoH consequently resumed the use of the vaccine in the national vaccination programme with two conditions: routine use of the vaccine would be offered to individuals aged 60 years and above; and the AstraZeneca vaccine can be offered to individuals below the age of 60 where the patient is aware of the risk and has consented to receive the
AstraZeneca vaccine.

Thrombotic thrombocytopenia refers to a condition of abnormal clotting that is associated with a low platelet count. The risk of clotting events following administration of the AstraZeneca vaccine is slightly higher in younger individuals (compared to not receiving the vaccine). It is however important to note that vaccines, like all medicines, can have side effects. The administration of vaccines is based on a risk-versus-benefit analysis.

While there is a slightly elevated risk of clotting events following the AstraZeneca vaccine, this is still significantly lower than the risk of clotting events following other common medical interventions such as the administration of heparin or the combined oral contraceptive pill, or the risk of clotting from natural events such as pregnancy. In fact, COVID-19 itself has a significantly higher risk of clotting events.

The symptoms of thrombotic thrombocytopenia may vary. This is a treatable condition and early detection of symptoms are more likely to lead to successful outcomes.

Individuals who have received the AstraZeneca vaccine within the last 14 days and subsequently develop any of the following symptoms of shortness of breath, chest pain, leg swelling, persistent abdominal pain, severe or persistent headaches, blurred vision and skin bruising (petechia) beyond the site of vaccination should seek prompt medical attention.

In addition, the ministry also highlighted that the vaccine has been assessed to be safe for use. However, you may experience common side effects, similar to other vaccines. These include pain at the injection site, mild fever, muscle or joint pain. Most side effects are mild and usually get better within a few days. If you encounter these side effects, you may take one to two tablets of paracetamol every six hours as needed. You should see a doctor if the symptoms get worse, or if the fever persists for more than two days.

Under the opt-in programme for the Oxford-Astrazeneca COVID-19 Vaccine, the AstraZeneca vaccine will be made available free of charge to all citizens, permanent residents, and foreign long-term residents in the country from May 6–29. This is made available on a voluntary basis and offered to all individuals above 18 on a-first-come-first-served basis until May 29 or until all available doses have been utilised.

Individuals who wish to receive the AstraZeneca vaccine can either reserve their appointment slots at the dedicated vaccination site via the BruHealth app, or walk-in to the vaccination site on the day of vaccination.

Individuals who reserved an appointment slot via the BruHealth app, and those above 60 will be given priority. To prevent overcrowding, individuals below 60 who choose to walk-in are advised to attend the vaccination site after 10am.

This opt-in programme will run alongside to the prioritisation phases outlined in the National COVID-19 Vaccination Strategy and allow individuals aged between 18 to 59 wishing to receive the vaccine earlier than they otherwise would be able to, the opportunity to do so with the AstraZeneca vaccine.

Meanwhile, persons who are chronically ill are at higher risk from COVID-19. Therefore, they are strongly recommended to receive the vaccine for personal protection as well as
protecting loved ones.

Vaccination with other brands for the general population is expected to commence in the fourth quarter this year and as such, individuals who do not opt in to receive the AstraZeneca vaccine will have to wait their turn following the prioritisation phases outlined in the National COVID-19 Vaccination Strategy.

Those who are not recommended to be vaccinated with AstraZeneca are pregnant women, severely immuno-compromised persons, and children under 18. Individuals who are severely immuno-compromised include those with a recent organ transplant, on cancer treatment or immunotherapy, or have poorly controlled HIV infection.

Persons who have had a previous allergic reaction to a previous dose of AstraZeneca vaccine or have a history of anaphylaxis to vaccines should not take the vaccine. If you are unsure whether or not the AstraZeneca vaccine is suitable for you, you should consult with your doctor to consider other suitable alternatives.