The first shipment of Covid-19 vaccines is expected to arrive in Malaysia at the end of this month.
While there are those who can’t wait, there are those with many questions, and fears.
Is the vaccine safe? Has it been properly tested? After all, it was produced in just nine months compared to normal vaccines that may take up to 15 years to be developed.
How about side effects? People have collapsed after getting the vaccine, some have died, even.
And there has been all that talk about mRNA which somehow transforms your genes and changes you and your progeny for life.
Have no fear, says Universiti Malaya virologist Prof Dr Sazaly Abu Bakar.
Like the self-destruct messages in the James Bond movies, the synthetic messenger RNA (mRNA) in the new Covid-19 vaccine will self-destruct once it has done its job and is not likely to cause havoc to the body.
He said the mRNA was fragile and would degrade soon after it enters the body to instruct cells to produce the spike protein of the SARS-CoV-2 virus which trigger an immune response to the virus.
“It’s like the self-destroying code in James Bond’s movies,” he said.
After the mRNA self-destructs, it cannot instruct the cells to produce spike protein of the virus anymore and with no instructions, the body stops producing the spike protein to trigger immune response.
“However, the immune system has a memory of the spike protein and is ready to fight the SARS-CoV-2 virus if it enters the body,” he said.
According to Pfizer’s website, the mRNA in the US-German Pfizer-BioNTech vaccine will instruct the cells to generate the spike protein to spur an immune response.
The immune response will then generate antibodies specific to the SARS-CoV-2 spike protein.
“No, you will not turn into a Frankenstein monster,” said Dr Sazaly, laughing off such fears by netizens.
“When the (initial) spike protein is generated, it lasts from a few minutes to a few hours and then gets gobbled up by the body’s antigen presenting cells – cells that eat up foreign material,” he said, adding that the spike protein was just a small component of the SARS-CoV-2 virus, just like the human finger on our body.
As for the speed in which the vaccine has been produced, the US Center for Disease Control (CDC) has said the mRNA technology had been researched for decades before it was used for Covid-19 vaccine production.
“mRNA vaccines have been studied before for flu, Zika, rabies, and cytomegalovirus (CMV). As soon as the necessary information about the virus that causes Covid-19 was available, scientists began designing the mRNA instructions for cells to build the unique spike protein into an mRNA vaccine,” said the CDC.
Future mRNA vaccine technology may allow for one vaccine to provide protection for multiple diseases, thus decreasing the number of shots needed for protection against common vaccine-preventable diseases, it said.
It could even be used to prevent or treat cancer.
Dr Sazaly also said some may also be concerned about live vaccines being used but mRNA vaccines are not live vaccines and do not use an infectious element, hence, they do not carry the risk of causing the disease in the person vaccinated.
The mRNA will also not get into the nucleus of the cell (the DNA) to alter the genes but will remain in the cytoplasm, a thick solution that fills each cell and is enclosed by the cell membrane.
The speed at which the vaccine was produced was also no surprise. The US announced the “Operation Warp Speed” on May 15 last year for medical products to be developed quickly as many of its citizens died from the disease.
As of today, close to 500,000 US citizens have died of Covid-19.
Massive amounts of funds were poured into the research from the US government and US private sector. There was none of the usual waiting for grants, infrastructure and volunteers.
Governments, public health agencies, international organisations and the private sector all pitched in.
If there are questions, it would be about the two-month follow-up requirement in the Phase 3 trial and continuous monitoring which is imposed on all vaccine and drug clinical trials.
“What scientists are worried about is an acute event – one that occurs immediately after vaccination – within minutes or hours.
“So far, the safety profile looks good and the risk is no different from other vaccination risks. The long-term effects are being monitored, though. If there’s anything unusual, it will be reported,” he said.
A wait for the long-tern effects would be ideal but we don’t live in an ideal world. Pressures for the vaccine to be released fast was immense, especially in the US, UK and Europe where hundreds of thousands have died.
“We need to balance the risks and benefit, with what is going on around us and the safety and efficacy data we have at hand,” said public health professor Dr Lokman Hakim Sulaiman.
Due to the urgency, all Covid-19 vaccines are currently registered under “emergency use.”
“Full registration can only be given after a long-term efficacy data is available but can we wait for another two years?” he asked.
The Pfizer-BioNTech vaccine Phase III clinical trial involving 43,661 volunteers was completed in the US, with interim results showing efficacy of 95% at preventing symptomatic Covid-19.
If it’s any assurance, the Bloomberg Covid-19 vaccine tracker revealed that as of Feb 10, 138 million Covid-19 vaccine doses had been given across 73 countries; 44.4 million doses in the US alone.
And so far, so good. There have been side effects, but the numbers are minimal.
The CDC website said side effects within seven days of Pfizer-BioNTech vaccination were fever, chills, tiredness, and headache, especially after the second dose. They are mostly mild to moderate.
“Although a few people in the clinical trials went to the hospital or died, data suggest that people who got the Pfizer-BioNTech vaccine were less likely to have these more serious outcomes.”
Yes, there are concerns over other more serious side effects but these are rare.
Among the rare adverse events that have occurred include anaphylaxis, a severe allergic reaction, in the case of the Pfizer-BioNTech vaccine.
Bell’s palsy, a condition which causes half of one’s face to droop, was reported from Moderna’s 30,000 trial participants (three from the vaccine group, and one from placebo) and another four from Pfizer’s 43,000-plus participants (all from vaccine group).
This is not enough to directly link the vaccine to Bell’s but those vaccinated should be monitored for such possible reactions.
In Norway, 33 people died after vaccination, all over age 75. So, the vaccine may not be advisable to the very old and frail.
There is one more fear – of antibody-drug enhancement (ADE). This is when other antibodies appear besides Covid-19 antibodies after a vaccination. These new antibodies do not protect against the virus but could potentially make a future Covid-19 re-infection worse.
So far, though, of the millions of people who have taken the vaccine, there have been little issues.
With the promising data, and more vaccines coming in, we may be on the road to recovery.
And Frankenstein will continue to remain the stuff of movies. - FMT
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