8 crucial questions surrounding COVID-19 vaccines

• Receiving the first dose of a vaccine is not enough to offer complete immunity nor will it enable the recipient to lead a normal life, so safety practices must be continued including wearing a mask, practicing social distancing, and regularly washing hands.
• No vaccine—no matter the brand—can provide 100% protection against COVID-19. Research studies show that most vaccines offer 50–95% protection against the virus, depending on the efficacy of that vaccine and the physical state of the recipient.
• Vaccine side effects differ depending on the individual. Should any recipient feel a fever coming on or pain at the injection site, they may take fever and pain relief medication. There is no need to take any medications to prevent possible side effects before receiving a vaccine.

Given that COVID-19 is still a relatively young phenomenon combined and its vaccines are very new, research and studies in the field are limited. As of June 9, 2021, Thailand has begun its vaccination drive for individuals above age 60 and those with underlying health conditions. However, there are still many people out there who are anxious and have questions about the vaccine, including whether it really offers protection, whether the vaccine itself poses a danger to health, or if it is possible to lead a normal life following a vaccination.

A1: Traditionally, vaccines are produced by taking a weakened form of a disease—which is incapable of causing an infection in the body—and injecting that substance into an individual to build their immunity against that disease. Many COVID-19 vaccines are no different in this regard as they usually involve using various strains of the virus to produce a vaccine which is then injected into the recipient to help them build immunity against the virus. The COVID-19 vaccines currently being used throughout the world have already been widely tested on animals as well as volunteers, with positive results due to increased immunity resulting in a significantly reduced risk of contracting COVID-19, or a reduced risk of severe symptoms.

Nonetheless, studies are still required to determine whether this immunity can be relied on in the long-term. Additionally, COVID-19 is a form of coronavirus that is constantly mutating, so there are questions as to whether the vaccine will remain effective in the future and whether it will be necessary to vaccinate the population annually, as is common with flu vaccines.

A2: Several companies are currently attempting to produce COVID-19 vaccinations as quickly as possible, and it is the method of production which has resulted in each vaccine being distinct from one another. A study carried out by the Research Clinic, Faculty of Medicine, Siriraj Hospital, found that the 4 most common vaccines currently in production are as follows:

1. Inactivated vaccines from China produced by SinoPharm, SinoVac Biotech, and the Wuhan Institute of Biological Products. These vaccines take a weakened form of the virus and inject it into the recipient to build their immunity against the disease. This method of vaccine production has been used for many years and is highly regarded, although production costs are often higher than for other vaccine types.
2. Adenovirus vector vaccines, such as those manufactured by CanSino from China, AstraZeneca from the UK, and Gamaleya from Russia, transfer genetic material from the COVID-19 virus into the Adenovirus.
3. mRNA vaccines like the one made by Moderna are approved by the U.S. Food and Drug Administration. This is the same type of vaccine currently being developed by doctors working at the Faculty of Medicine, Chulalongkorn University, with the vaccine already having passed stage 3 of testing. These vaccines result in strengthened immunity among adults and the elderly. There are other companies currently developing their own version, such as German companies BioNTech and Pfizer. mRNA represents a new type of vaccination and its benefits include rapid production times due to the ease with which it can be made.
4. Protein-based vaccines take protein cells found on the surface of the COVID-19 virus and use them to produce a vaccination against the disease. Companies currently developing such vaccines include Novavax from America and Sanofi (in partnership with GSK).

There are still not enough studies into the long-term efficacy of COVID-19 vaccines so answering questions like how long immunity will last and how often future vaccinations will be required must wait until more information is available.

A3: Receiving the first dose a multiple-dose vaccine is not enough to offer complete immunity nor will it enable the recipient to lead a normal life, so safety practices must be continued including wearing a mask, practicing social distancing, and regularly washing hands. Although the American Centers for Disease Control (CDC) released a statement on April 28, 2021 which said that those who had received 2 doses of the vaccine would now be able to venture outside in open spaces without the need for a mask, including meeting with friends as long as they had also had their complete course of vaccinations, the CDC still recommended that a mask be worn, social distancing be maintained where possible, and crowded locations be avoided. However, this information is not suitable for use in the context of Thailand as the vaccine used here is a different type. In addition, most of the population remains unvaccinated and therefore does not have immunity against the virus, thus placing people at continued risk of infection or transmission of the disease to others. While there is currently no information to confirm the risk levels, it has been found that even those who have received a full course of vaccinations can still potentially contract and fall ill with the virus (information as of May 20, 2021). It is vital that everybody continues to take good care of their health to reduce the number of infections and protect themselves from the risks posed by COVID-19.

A4: Vaccines are one of the processes used to halt the spread of COVID-19. When an individual receives the vaccine—whatever brand that may be—it triggers a physical process that boosts immunity against the virus, protects against illness resulting from an infection, reduces the occurrence of severe symptoms, and decreases the likelihood of death caused by the disease. It is therefore entirely normal for people to experience side effects following a vaccine, which may be severe, such as anaphylaxis, or moderate, such as fever, aches and pains, or rash. Deaths resulting from vaccines can usually be attributed to anaphylaxis or other underlying issues that may be unrelated to the vaccine itself.

A5: The severity of the recent COVID-19 outbreak that has affected every part of the population, including children, men, women, and the elderly, combined with the limited number of vaccines available, has led to questions regarding which groups should be first on the list to receive a vaccination.

The WHO has recommended that the following 3 main groups be prioritized in nationwide vaccination drives, owing to their level of risk:

1. Medical staff: Their risk of direct contact with infected patients, as well as the essential nature of their work, means medical staff must be healthy and have strong immunity.
2. The elderly: This group has weakened immunity due to their age, which places them at risk of developing severe symptoms and even losing their lives in the event of an infection.
3. Patients with underlying health conditions: Groups with the following health conditions are at greater risk and should therefore be prioritized: the obese, diabetics, and those with high blood pressure.

Unfortunately, the most recent outbreak beginning in April, 2021 (information from May 29, 2021) has seen COVID-19 spread more widely than before. Consequently, those residing in high-risk areas or provinces, such as Bangkok, have begun to be prioritized for vaccinations. Additionally, on May 31, 2021, the government announced that the entire population should register to receive vaccinations. Nonetheless, all preventive measures must still be adhered to in order to reduce the burden placed on the public health system, including wearing masks, regularly washing hands, and social distancing, as these are also highly effective in protecting people against the virus.

A6: There are several vaccines that only require one dose to offer lifelong protection, such as the herpes zoster vaccine. However, it is currently (March 11, 2021) not known just how long a single dose of a COVID-19 vaccine will offer protection because of how new these vaccines are. Indeed, they have only been used for less than a year so far, so recipients must be monitored closely to see if their immunity remains after one year and how much that immunity decreases over time. Nevertheless, trends are beginning to emerge which show that a single dose is insufficient, as COVID-19—a member of the coronavirus family—constantly mutates and develops new strains. It is possible that a vaccine received today will not be effective against future strains of the virus, making ongoing monitoring especially important. Therefore, public health advice regarding ways to stem the spread of the virus, such as wearing a mask, regularly washing hands, and social distancing, remain essential.

A7: By the end of January, 2021, one million doses of COVID-19 vaccines had been administered worldwide. However, there are news reports of people becoming infected with COVID-19 despite having received the vaccine.

Factor 1 – It takes time between the administration of a vaccine and the buildup of immunity. Most COVID-19 vaccines currently in use require 2 doses in order to ensure the body has sufficient immunity against the virus. If a recipient contracts the virus while the body is still building immunity, or if that immunity is not yet at full strength, the individual could become infected.

Factor 2 – Vaccines do not offer 100% protection against COVID-19 regardless of the manufacturer. Research studies into vaccines undertaken by various vaccine manufacturers have revealed that COVID-19 vaccines offer 50–95% protection, depending on the vaccine and physical response of the recipient.

Factor 3 – Experts in infectious diseases have said that vaccines can offer protection against COVID-19 but that the issue of contracting the virus requires further research as existing studies have been inconclusive. Although vaccine recipients might contract the virus, its effects and symptoms will be significantly reduced compared to someone who has not received a vaccine.

Factor 4 – Vaccines are not an effective form of treatment, meaning that someone who has already contracted the virus will not have their symptoms alleviated by receiving the COVID-19 vaccine.

To conclude, people cannot be complacent in their approach to disease prevention despite already having received the COVID-19 vaccine.

1. Try to get at least 6–8 hours of sleep the night before the vaccine to ensure you wake up feeling refreshed.
2. Do your best to drink between 500cc and 1 liter of drinking water the morning of your vaccination, although not all at the same time; many people have previously misunderstood this advice and experienced bloating. Instead, periodically sip from a bottle of clean drinking water.
3. Avoid caffeinated drinks as they can cause an elevated heart rate. Caffeine ingested on the day of the vaccine could lead to palpitations.
4. Vaccine side effects differ depending on the individual. Should you feel a fever coming on or pain at the injection site, you may take fever and pain relief medication. There is no need to take any medications to prevent possible side effects before receiving a vaccine.

Finally, COVID-19 being a relatively new disease means that information associated with it is constantly being updated as new research and studies are concluded. It is advised that people carefully select news sources through which they gather their knowledge to ensure they are trustworthy and informed by experts in the field.