YSN-ASM Science Café
Looking Beyond COVID-19 Vaccination

Around 500,000 doses of the COVID-19 vaccine were administered in the first phase of the vaccination programme in Malaysia (at the time of broadcast). The next phase will prioritise the elderly, people with comorbidities as well as those with disabilities.  Dr Aizati Athirah moderated this Science Café session on looking beyond the COVID-19 vaccination. She was joined by Dr Leow Chiuan Yee from Universiti Sains Malaysia and Dr Irene Looi from Hospital Seberang Jaya, Pulau Pinang.

Dr Leow began the session by introducing viewers to the types of vaccines available to treat COVID-19. There are five vaccines that are used worldwide to treat COVID-19:

• Pfizer-BioNTech: This is a messenger RNA or mRNA vaccine, which instructs the body’s cells to produce a protein that triggers an immune response. A COVID-19 mRNA vaccine teaches our cells to produce a ‘spike protein’ which is found on the surface of the coronavirus. The body’s immune system then recognises this protein and develops an antibody to protect against it. Unlike traditional vaccines, this type contains only synthetic components, not a live virus. Pfizer-BioNTech boasts an efficacy of 95% and must be administered in two doses.
• Oxford-AstraZeneca: It uses a modified virus to deliver a small portion of the virus’ genetic code to the body’s cells, teaching them to produce the spike protein found in the coronavirus and build an immune response to it. This vaccine must also be administered in two doses and has an efficacy rate of 62% to 90%.
• Sinovac: The Sinovac vaccine is an inactivated vaccine, which means it uses killed virus particles to trigger the body’s immune response to a virus. Suitable for those with weak immune systems, Sinovac’s vaccine has an efficacy of 50.4% to 91.25%.
• CanSino Biologics: Chinese pharmaceutical company CanSino Biologics co-developed this vaccine with the Beijing Institute of Biotechnology and the Academy of Military Medical Sciences. It is currently in use in China, Mexico and Pakistan. The CanSinoBIO vaccine is also a viral vector vaccine and the only vaccine among the five listed in the handbook that can be administered in one shot (besides the newly approved Johnson & Johnson Janssen vaccine). It has a 65.7% efficacy rate.
• Johnson & Johnson: Known as the Janssen Ad26.CoV2.S vaccine, this single-dose viral vector vaccine recently received conditional approval for emergency useby the Malaysian government, and doses will be secured for the country through COVAX. The Janssen vaccine has been tested and declared safe to use by the European Medicines Agency and the US Food And Drug Administration. According to this report by the World Health Organisation, this vaccine was found to have a 85.4% efficacy rate against hospitalisation and severe symptoms of COVID-19 approximately 28 days after inoculation.
• Sputnik V: A viral vector vaccine by Russia’s Gamaleya Research Institute, the Sputnik V shot is administered in two doses around 21 days apart. It boasts an efficacy of 91.6% and is being used in Russia, South Korea, Brazil, Argentina and Belarus.

(Source)

Dr Aizati continued the session with a few questions. First, on the topic of herd immunity: Dr Leow explained that up to 80% of the population needs to be vaccinated for it to achieved herd immunity. The remaining 20% would comprise those who are not encouraged to take the vaccine due to limited trials and information on the effects of the vaccine on these people, such as young children under 18 years of age, pregnant women, those who are going through cancer treatment or those experiencing hypersensitivity to drugs.

Second, Dr Aizati asked whether it is advisable to take two different vaccines at once. Dr Leow said that because clinical trials have always involved just one type of vaccine, not much data is formed regarding the effects of combining vaccines. Therefore, there is not much information on the efficacy as well as the safety of combining vaccine types.

Third, Dr Aizati asked about the efficacy of the current vaccines against mutated variants of the SARS-CoV-2 virus. Dr Leow presented a diagram that depicts the efficacy of the vaccines against different variants. The vaccine demonstrates high efficacy towards the wild type (original variant) and seems to have less efficacy  on newer variants that have developed in different regions. Going in-depth, Dr Leow showed the efficacy of the vaccine types against specific variants. Against the original variant, a relatively high efficacy was recorded: Pfizer (95%), Moderna (94%), J&J (72% in US trials), AstraZeneca (60-90%) and Sinovac (50%). These vaccines exhibited similar efficacies agains the UK Variant, but all exhibited reduced antibody levels or efficacy against the South African Variant. Meanwhile, only Pfizer and AstraZeneca maintained their efficacies against the Brazilian Variant while others faltered (or in the case of Moderna, insufficient data). As such, Dr Leow insisted for us to get vaccinated as soon as possible to prevent complications and curb the spread of the virus, which is a reason why it can mutate into different variants.

Dr Irene joined the session soon after. Dr Aizati engaged with Dr Irene with a question regarding who constitutes those categorised as those with co-morbidities who will be the focus of the second phase of the National Vaccination Programme. Dr Irene stated that high risk patients include those with low immunity, have chronic diseases (stroke, heart problems, diabetes) and  those undergoing kidney or cancer treatments. These are the very candidates that are crucial to take the vaccine as soon as possible.

Dr Irene cited an example of thalassemia patients expressing concern over taking the COVID-19 vaccine. Dr Irene clarified that thalassemia is not a contraindication for the vaccine and is such safe to be taken. Next, Dr Irene addressed the concern of cancer patients taking the COVID-19 vaccine. Patients may check with their oncology practitioners whether it is safe to take the vaccine whether they are cleared to take it. Dr Irene also dispelled the worry expressed by stroke patients on taking the vaccine as long as the patient is diligent in taking their regular medicines. In essence, having a chronic disease is not a contraindication.

If this is the case, then who are considered unfit to take the COVID-19 vaccine? According to Dr Irene, those who have experienced allergies when taking other vaccines. This can be detected by taking a walk down memory lane and checking what effects have they experienced when taking vaccination in their childhood. A more recent check can be done by those who have taken hepatitis B or flu vaccines. Those who have experience adverse side effects from the above vaccinations will need to take extra precaution when taking the COVID-19 vaccine.

Dr Aizati posed a question regarding possible drug-vaccine interactions, which Dr Irene stated there are no known interactions associated with COVID-19 vaccine. What needs to be taken into account is any previous adverse reactions experienced from other vaccines.

What about pregnant or breastfeeding women? Dr Irene stated that clinical trials did not involve pregnant or breastfeeding women in the trials, therefore there is insufficient data on the effects of the vaccine on this group of the population. Dr Irene cited a story she experienced relating to pregnant nurses working in the industry. The nurses involved expressed concern for their safety against COVD-19 having worked in a high exposure environment therefore insisted that they would also like to get vaccinated. As such, in view of the highly encouraged practice of getting the vaccine as soon as possible coupled with their high risk environment, the nurses may take the vaccine.

Dr Irene went on to elaborate on the side effects that may be experienced by vaccinated people. Common side effects include tiredness, pain or swelling at the injection site, fever or chills and headaches. Dr Irene notes that side effects experienced during the second injection would be more pronounced. Having said that, Dr Irene said that these are transient and will go away soon. Any lingering side effect or pains can be addressed with NSAIDs such as Panadol or by consulting your general practitioners. Dr Irene also encouraged people to keep close contact with their GPs regarding the side effects they experienced as doctors typically have an Adverse Drug Reaction (ADR) form to report on drug reactions from patients. She also reminded everyone to update the side effect reporting via MySejahtera, which is available after taking the vaccine.

Dr Aizati engaged with Dr Leow to ask whether someone who has contracted and recovered from COVID-19 still needs to take the vaccine. Dr Leow explained that depending on the viral load experienced by the patient, the antibodies will last around 3-6 months. Using a graph that demonstrates the antibody level with days, he explained that after the first dose, antibody levels will spike for a certain period of time, followed by a reduction over time, down to a minimum level. This is a risky period for patients. The second dose should be administered within the specific time frame to induce another spike that is better and stronger to trigger memory cells that will attack the virus. Dr Yee states that after infection and/or upon completion of the initial two doses, patients are advised to take the vaccine again after six months to maintain the protection against infection.

Dr Aizati asked both guest speakers on whether someone can contract COVID-19 after completing the vaccination. Dr Irene states that it is still possible to get COVID-19 even after completing the vaccination. She stressed that even with vaccination, all SOPs still applies and are encouraged: washing your hands frequently, physical distancing, etc. Aside from that, having the vaccine also reduces the possibility of transmission of the disease to you when exposed to the virus, as well as to reduce the severity of the disease’s effects.