What are in the COVID-19 vaccines?

By Joseph B.A. Marzan

 

Infectious disease specialists in Iloilo City are “very eager” to talk to the media in boosting confidence of the public on getting themselves vaccinated against the coronavirus disease 2019 (Covid-19), according to one of their own.

The Iloilo City Government has started its information blitz on COVID-19 vaccines by publishing daily information campaigns and tapping local experts to get out the message in shoring up vaccine confidence.

This, after the city government learned that only 29% of residents showed willingness to be inoculated.

The data is based on the vaccination consent forms distributed in the barangays early this month.

Based on the 9,731 returned/filled up consent forms so far, 29% are willing to be vaccinated while 71% are hesitant. Iloilo City’s population is more than 400,000.

Dr. Ludivico Jurao, assistant administrator for Patient Care and Head of the Infection Control at the Iloilo Doctors Hospital, talked to Daily Guardian on Air last Friday to discuss Covid-19 vaccines and their safety.

He said members of the Western Visayas Chapter of the Philippine Society of Microbiology and Infectious Diseases (PSMID) are always eager to give science-based information to the public

“We in PSMID Western Visayas are always willing to give an interview so our information is based on science and not hearsay,” Jurao said.

 

TYPES OF VACCINES

Jurao explained that companies developing vaccines against Covid-19 have distinctions between them.

He explained that the more common components used for vaccines are the “messenger Ribonucleic Acid” (mRNA), a dead virus, or a “vector”.

mRNA-based vaccines send instructions to the cells to create a “harmless” piece of the spike protein, which is found on the surface of the virus that causes Covid-19.

These proteins are recognized by the human body’s immune system as a foreign object, which then develops an “immune response” by creating antibodies, which are also proteins created to go up against a specific antigen.

At the end of the process, the body has now been “trained” to develop a response to SARS-COV-2 which causes Covid-19.

mRNA vaccines are the types developed by American manufacturer Moderna, and German biotech company BioNTech in partnership with American drug company Pfizer.

The inactivated vaccine, or what Jurao calls the “dead virus”, is an inactivated version of the virus, which are not as strong as live or “weakened” vaccines.

People who are inoculated with these types of vaccines may be advised to get several doses, or what is more commonly known as “booster shots”, over time.

According to the U.S. Department of Health and Human Services, inactivated vaccines are used to protect against disease such as Hepatitis A, Flu, Polio, and Rabies.

Inactivated Covid-19 vaccines are the ones being developed by Chinese companies Sinovac and Sinopharm.

Viral vector vaccines are similar to the mRNA vaccines, but they instead use a modified version of a different, more harmless virus to deliver instructions to the cells.

Just like the mRNA vaccines, they also use cell systems to produce Covid-19 spike protein to trigger the immune system, which will then create the antibodies.

This version of the vaccine is the one being used by British-Swedish pharmaceutical company AstraZeneca for its AZD1222 vaccine, which was the variant ordered by Iloilo City and province.

 

SAFETY

Jurao said that the EUAs, which were encouraged by the World Health Organization (WHO), are proof that the Covid-19 vaccines are safe despite the virus’ novelty.

“In terms of safety and efficacy, we can say that it is needed at this stage because of the reason of the pandemic. We cannot move freely if we’re talking about a pandemic. Covid-19 is a very new virus which has caused a global pandemic that we just came to know. Even us infectious disease specialists, it is our first time encountering cases of Covid-19. Right now, the only way our lives can normalize in the new normal is through mass vaccination to prevent the spread of severe illness,” said Jurao.

He said that public hesitancy against vaccination is more likely due to the “magnified” attention being given to side effects or adverse effects appearing after vaccination.

He explained that the adverse effects of the vaccine are common and can be comparable to having food-based allergies.

“When we think about it, it’s like when people have shrimp allergies. Almost all of us eat shrimp. But there are people who have severe allergies to shrimp, so when they eat shrimp their allergies will flare up or they can go to anaphylactic shock. In the same manner, our response to the vaccine, the vaccine simulates the natural infection, so instead of getting Covid-19, we can have components of the Covid vaccine which can stimulate immunity for stronger response in case of exposure to Covid-19,” Jurao explained.

A common side effect Jurao cited was idiopathic thrombocytopenic purpura (ITP), an immune disease where the blood does not clot normally and the platelet count lowers.

He stated that in Covid-19 cases, the immune system cannot distinguish between platelets and the viral infection, which leads them to also destroy the platelets.

The usual process, according to Jurao, is that patients who develop ITP should be immediately hospitalized for treatment and observation by hematologists.

“Any viral infection can cause ITP, and maybe there are similarities, [between] the proteins in the platelets and in the makeup of Covid-19. Our immunity cannot distinguish between our platelets and Covid-19, so in a way, therefore, we have cases of ITP, which lowers our platelets because the body destroys the platelets themselves, so there would be bleeding. It is part of the reaction to the vaccines in general and not just Covid-19. In an ordinary infection, when patients have ITP, they are immediately hospitalized and observed by our hematologists, and sometimes we even do transfusion to correct the sudden decrease in platelets,” he said.

 

HERD IMMUNITY 

As to those who argue that herd immunity can be achieved by contracting Covid-19, Jurao said reinfection had already been proven, citing a case from their own hospital and other incidents.

“As we have learned, there have been many cases of reinfection of the previous Covid-19. Like here at the Doctors Hospital, we have had one employee who was exposed after two months and developed Covid-19 again. There was also news of a Filipina coming from [overseas] who developed Covid-19 despite already being immunized,” he stated.

He added that all verified information that they had been receiving about Covid-19 has been leading to the thought that protection against the disease was not permanent and it will only last between 9 to 10 months.

“Apparently, this is the information given to us in the medical community, that there is no lifelong immunity even after a Covid-19 infection. Natural infections provide only short-lived immunity, so that is data we are still collating as of now, so we can know how often the vaccination process should be, because in the current vaccine, they are saying that there is still protection between 9 to 10 months,” he said.

He argued, however, that vaccination is still necessary to prevent the development of Covid-19 inside the body or its severity.

“We have to specify that infections and diseases are different. For example, if I get immunized, I can still get an infection of Covid-19. It means that Covid-19 can enter through my nose, my mouth, then it can be carried to the home, I talk to people, but I won’t get sick. The vaccine is to prevent the disease, so at least if you are in the vulnerable population, you will not get sick to the point that you might die, or get intubated, or get severity,” he explained.

 

MYTHS DEBUNKED

Jurao also dispelled the notion that vaccines alter the deoxyribonucleic acid (DNA), which contains the genetic information of humans.

He explained that the materials in the vaccines will also be destroyed by the immune system once they are done “instructing the body”.

“It will not definitely alter [DNA]. The technology they used, mRNA, for example, codes the spikes. We have seen Covid-19, it is round and it has spikes on the outside. The mRNA inserted codes spikes of the virus, and our body has a simple immunity rule, which is what is non-cell should be destroyed. So the virus or bacteria entering our bodies, it will be destroyed by our immune system,” he said.

Another Covid-19 vaccine myth Jurao debunked is infertility among the recipients, saying that Covid-19 had been observed to lower sperm count among men who have died from the disease, therefore immunization will actually help protect against this effect.

“The infection of Covid-19 has been proven to cause the reduction of the number of sperm cells, because this was observed from autopsy reports of those who died from Covid-19. What we should do therefore is to immunize so we don’t get infected by Covid-19, or if we do get infected very mildly and not severely, our sperm production won’t be affected,” he said.

He encouraged the public to get vaccinated, since there are no advised contra-indications even as he cited the prioritization of vulnerable persons, like senior citizens, in the immunization process.

“Our limitation on the vaccines is that on the Phase 1 to Phase 3 of the trial normally, healthy individuals without comorbidities. But in this state of a pandemic, our option there is to have guidelines, like in the Philippine Pediatric Society, the Philippine Society of Immunology, and Philippine Vaccinology Society, apparently, there aren’t any contra-indications in age groups, even elderly individuals are prioritized in immunization,” he said.

He said that the only persons known to be warned against undergoing vaccination are pregnant women, especially those who are in their first trimester, mainly due to the novelty of Covid-19, and the lack of data on the vaccines’ effectivity when it came to them.

“Unfortunately, the Philippine Society of Obstetrics and Gynecology is giving a caution especially during the first three months of pregnancy, because this is where the organs and organ systems of a child are developing. Therefore, we cannot assure the effects of the vaccine. So, we have opted to defer vaccinations especially to pregnant women on the first three months of pregnancy. If we don’t have a lot of data, then we have to play safe as well because this is a new vaccine and a new disease to us,” he stated.

As of this writing, only three vaccines have been given Emergency Use Authorization (EUA) by our Food and Drug Administration (FDA): the Pfizer-BioNTech BNT162b2, AZD1222, and Sinovac’s CoronaVac.