COVID-19 Vaccines: How Are They Different?
It’s been a year since the Philippines detected its first COVID-19 case and almost a year since we’ve been on lockdown. Today, life isn’t the same as it was before and we’re still struggling to get through this pandemic. However, we’re finally close to halting the spread of the virus with the swift invention of Coronavirus vaccines.
As of December 2020, there are already more than types of 200 vaccines for COVID-19 being developed. At least 52 of these vaccines have already completed human trials. Quite a few vaccines are already getting rolled out throughout the world, and the Philippines’ turn will come sooner than you think.
The Philippine government recently announced that COVID-19 vaccinations will begin towards the end of the first quarter of 2021.
While the government hasn’t finished procuring all the necessary vaccines to cover the entire population, data on what vaccines we can expect are already final and the vaccines will be coming from different sources.
Before we dive further into the specifics of each vaccine, let’s discuss some necessary side notes first.
The different types of vaccines
Vaccines work by mimicking the cause of the disease (virus or bacteria) and triggers the creation of antibodies in the human body. This teaches the body how to defend against the particular disease without making you fall sick in the first place. Thus, your antibodies will kill the real virus or bacteria before it can harm the body.
Today, vaccines can differ in composition and how they can achieve an immune response to create antibodies.
Vaccines can be in a form of inactivated virus or bacteria, or in a form of a genetic product (like mRNA vaccines) that creates protein copies without causing disease.
| mRNA | Adenovirus |
| Genetic product that creates protein copies without causing disease. This teaches the body to create the specific antibodies without exposing the body to the actual virus or bacteria. | An inactivated, weakened, or killed copies of the whole of the virus or bacteria |
What is an Emergency Use Authorization (EUA)?
According to the FDA, the Emergency Use Authorization is an authorization granted through a risk-based procedure for assessing unregistered (under development) vaccines or drugs during public health emergencies of international concern. It aims to expedite the availability of the vaccine or drug to people affected by public health emergencies based on an essential set of available quality, safety, and efficacy performance data.
Know your vaccine
The Philippines has already secured its first batch of Coronavirus vaccines to be administered from the end of February until the end of the first quarter, and its currently in negotiations with more vaccine providers. What are those vaccines? Let’s discuss them below.
Pfizer-BioNTech
The most popular among the COVID-19 vaccines. This vaccine got its Emergency Use Authorization (EUA) on December 11’, 2020.
One of the challenges that Pfizer faces come in the form of storage. This particular mRNA vaccine requires a special storage freezer that can go way below the freezing point, which isn’t commercially available. While the Philippines has secured freezers for this said vaccine, distribution of the Pfizer Covid-19 vaccine outside major cities would pose a major challenge due to logistics and storage.
| Type | mRNA |
| How many doses | 2 doses, 21 days apart |
| Price | ₱2,739 for 2 doses |
| Efficacy | 95% |
| Storage requirement | -70 C |
Moderna
Another mRNA type of COVID-19 vaccine with an efficacy rate of 94.5%. Moderna got its FDA authorization on December 19, 2020 and is one of the most commonly used vaccines in the USA. Unlike the Pfizer vaccine, this vaccine is stable and can be stored at a temperature of a standard home or medical refrigerator.
| Type | mRNA |
| How many doses | 2 doses, 21 days apart |
| Price | ₱3,904 to ₱4,504 |
| Efficacy | 95% |
| Storage requirement | -25 C to - 15 C |
AstraZeneca-University of Oxford
AstraZeneca and the University of Oxford announced on November 23 that the initial performance of their Coronavirus vaccine showed high-level results (90% efficacy) in preventing COVID-19 transmission with no hospitalizations or severe reactions in people receiving it. Another round of tests was done a month apart for the 2nd dose of the vaccine (full dose) and it showed 62% efficacy. The combined analysis showed an average efficacy of 70%.
The AstraZeneca vaccine only requires a normal refrigerator for storage, thus making it easier to transport, handle, and administer within existing healthcare settings.
The AstraZeneca and University of Oxford’s vaccine use technology from an Oxford spinout company, Vaccitech. It deploys a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees. It contains the genetic materials of the spike protein. After vaccination, the cells produce the spike protein, stimulating the immune system to attack the SARS-CoV-2 virus.
| Type | Adenovirus based |
| How many doses | 2 doses, 28 days apart |
| Price | ₱6,10 |
| Efficacy | 70% |
| Storage requirement | 2 to 8 C |
Johnson & Johnson
Johnson & Johnson rolled out its second round of phase 3 trial on November 15, 2020. This time, it was conducted on a global scope. A total of 60,000 volunteers worldwide were expected to participate in the trial. Unlike the rest of the vaccines, Johnson and Johnson’s only requires a single dose to get maximum protection.
Their Phase III ensemble trial demonstrated 66% effectiveness in preventing moderate-to-severe COVID-19 infections after 28 days from vaccination. Preventing severe conditions, however, showed a 100% efficacy after 49 days from vaccination.
The Johnson & Johnson’s vaccine uses the company’s AdVac technology platform which was used to develop their approved vaccines for Ebola, Zika, RSV, and their HIV investigational vaccine candidates. It’s a traditional vaccine that uses an inactivated common cold virus, similar to what the AstraZeneca-University of Oxford program utilizes.
| Type | Adenovirus based |
| How many doses | 1 |
| Price | No data available yet |
| Efficacy | 72% |
| Storage requirement | 2 - 8 C |
Sinovac Biotech
A China-based vaccine that is reported to have a 50.38% efficacy in late-stage clinical trials in Brazil. However, Sinovac Biotech’s clinical trials demonstrated dramatically varying efficacy rates. In Indonesia, it showed an efficacy rate of 65% for a trial that had only 1,620 participants. Meanwhile, in Turkey, it managed to garner an efficacy rate of 91.25% during its December 2020 trial. In its most recent trial in Brazil conducted early this year, it reported a 78% efficacy rate in mild cases while 100% against severe and moderate infections.
| Type | Adenovirus based |
| How many doses | 2 |
| Price | ₱1,300 |
| Efficacy | 50% to 78% |
| Storage requirement | 2 - 8 C |
Efficacy vs effectivity
Vaccine development is a long, complex process that usually lasts for 10-15 years and can involve a combination of public and private cooperation. However, the case for the current pandemic called for the immediate creation of vaccines that are safe to use by the public. Due to this, while the vaccines created are indeed safe and have already proven to prevent transmission of the COVID-19 virus, data on the real-world effectiveness of the vaccines aren’t available yet. Thus, in the context of the Coronavirus vaccines, the word efficacy was used to represent its performance.
Efficacy is defined as the performance of an intervention under ideal and controlled circumstances – the performance of the vaccines during the trials. Effectiveness on the other hand is the performance of the vaccine under real-world conditions – which most of the vaccines don’t have yet.
What are the possible side effects of vaccination?
After vaccination, it’s normal to feel pain, itchiness, redness, or swelling at the injection site which may last a few hours. Fever, the feeling of weakness or fatigue, dizziness, headache, nausea, or diarrhea are also common too. While these side effects are normal, you should consult a doctor if they become unmanageable or intolerable.
Who will get the vaccines first?
According to the DOH, the priority for the COVID-19 vaccination are our frontline health workers, senior citizens, indigent population, and uniformed personnel are the priority groups to be vaccinated.
They will be prioritized since they’re either highly exposed to the pandemic or possess a higher risk of being fatality if infected.
Can I purchase the vaccine from private clinics or pharmacies?
At the current state of the country and the availability of the vaccines, only the government is duly authorized to procure and administer vaccines. The FDA hasn’t issued an authorization for market distribution yet, thus COVID-19 vaccines are not yet allowed to be sold to the public.
Is the vaccine free?
As per the most recent announcement, the vaccine is only free to the priority groups such as the frontliners and senior citizens. However, the government is still in continuous negotiations with vaccine manufacturers to secure n adequate vaccine supply for all Filipinos, including those not in the priority groups. Until then, we’ll have to wait for further announcements.
When will the COVID-19 vaccine be available?
The government is currently in the advanced stages of negotiations with various vaccine manufacturers. We expect the first vaccine supply to arrive in the first quarter of 2021.
Why should you take the vaccine even though its efficacy is not 100%?
While the vaccines have varying efficacy, they all prevent severe infection from COVID-19 by 99%. Not only will this drastically cut down the hospitalization and mortality rate of the vaccine, but it will also lessen the load on the healthcare system. At the end of the day, the vaccines will render the virus incapable of taking our lives and our healthcare system will not be overwhelmed with hospitalizations due to COVID-19 – and that’s a win! So, whenever the vaccine gets rolled out, take whatever you can, they’re all proven effective to save your life by 100%.
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