Chennai

Contagion, a 2011 film directed by Steven Soderbergh, witnessed a massive revival in popularity because of its stunning similarities with the current pandemic’s onset. The film depicts an outbreak of a deadly virus and medical researchers’ attempts worldwide to contain it. The movie mirrored the existing corona pandemic eerily well. One of the two things in the film, which viewers deemed inaccurate, was developing the vaccine in in the movie, in a short time to be unrealistic.

Further, as the film unfurls, CDC inadvertently stumbles on a weakened strain of the virus in a monkey. Scientist Hextall (Jennifer Ehle) using an attenuated virus inoculates herself with it to circumvent the “informed consent test subject process” and visits her infected father to check if she has developed an immunity. As she fails to contract the virus from her father, the vaccine is proclaimed a success, and the vaccine miraculously zooms into mass-production.

Vaccines have easily staved off hundreds of millions of demises since 1796 when Edward Jenner inoculated a boy with cowpox to prevent smallpox. Outside Hollywood, vaccine development is a long, complicated process, costing up to $500 million and often lasting 10-15 years encompassing several years of testing and some more for obtaining authorisation from the health authorities for its delivery as a viable vaccine. But, science has proved itself to be stranger than fiction. Even before the pandemic could complete a year of its existence, COVID-19 vaccines have arrived at unimaginable breakneck speed due to the scientists’ stupendous efforts. The UK, EU, US and a few other nations have commenced administering vaccines within a year of coronavirus unleashing a devastating pandemic.

All vaccines strive to expose the body to an antigen that won’t cause disease and provoke an immune response that can block or kill the virus when a person becomes infected. At least eight types of vaccines are getting employed against the coronavirus, most important of them being attenuated viruses, DNA or RNA vaccines and viral protein-based vaccines. Altogether more than 50 teams are working on formulating vaccines against COVID worldwide.

Of them, mRNA is the recent unusual approach to vaccines. Cells make use of mRNA to make proteins. mRNA vaccines have strands of genetic material called mRNA inside a special coating. That coating protects the mRNA from enzymes in the body that would otherwise break it down. It also helps the mRNA enter the dendritic cells and macrophages in the lymph node near the vaccination site. mRNA contains the code to make a portion of the “spike protein” unique to SARS-CoV-2. The mRNA vaccine does not cause any harm to the person vaccinated as only a part of the antigenic protein is made. After the piece of the spike protein is assembled, the cell disassembles the mRNA strand and digests it using enzymes in the cell. The significance of this process is that the mRNA never enters the nucleus. Hence, it disproves the validity of anti-vaccination activists’ claim that mRNA vaccines can modify genetic material. The protein or the antigen once expressed on the cell surface stimulates the immune system to commence generating antibodies and activating T-cells to fight off SARS-CoV-2 virus, which is an indication that the immune system has been geared to protect against future infection.

Researchers have experimented with mRNA vaccines for decades; however, there were no licensed mRNA vaccines thus far. Some early-stage clinical trials carried out for influenza, Zika, rabies, and cytomegalovirus failed to yield much success due to free RNA instability in the body. Pardi, along with Karikó and Weissman, overcame the shortcomings by developing a technique of encasing mRNA in small bubbles of fat known as lipid nanoparticles (LNPs), which protected and enhanced its delivery into cells.

The first approved COVID-19 vaccines in the world with demonstrable efficacy, developed by Pfizer-BioNTech and Moderna, are based on mRNA technology. Pfizer-BioNTech was granted an Emergency Use Authorization on December 11, 2020, and Moderna on December 17, 2020.

The clinical trial data for the Pfizer and Moderna vaccines indicate they are about 95 per cent effective in preventing illness when both shots of the dual-injection immunisation are given, three weeks to a month apart. The main difference between the two vaccines being that Moderna’s vaccine can be stored for up to 30 days in a typical household refrigerator. At Imperial College in London, Robin Shattock’s team is working on a ‘self-amplifying RNA’ vaccine that will be far cheaper than the BioNTech/Pfizer vaccine ($39 for two shots) or the Moderna jab ($74 for 2 shots) and require as little as one-hundredth of the amount of vaccine. The mRNA technique means future pandemics could be halted more swiftly as the carrier is already available.

India’s first mRNA vaccine HGCO19 developed by Pune-based company Gennova has received approval from Indian Drug Regulators to initiate Phase 1 and Phase 2 clinical trials. COVID-19 vaccine trials in India are progressing well. Two of the five vaccines undergoing human clinical trials in India have reached the phase-3 stage. Bharat Biotech claims its inactivated vaccines called Covexin is the safest, with lesser adverse effects when compared to mRNA vaccines. The Serum Institute of India is testing the other Oxford-AstraZeneca vaccine Covishield. Covishield is one of the three coronavirus vaccines under consideration for emergency use authorisation in India after Pfizer’s BNT162b2 and Bharat Biotech’s Covexin. India has recorded more than 10 million COVID-19 cases and over 1,45,000 deaths from the disease so far. India is planning to begin vaccinating people against COVID-19 in January this year. The vaccination programme aims to reach 300 million people by early August.

In ‘I am legend’, a 2007 film starring Will Smith adapted from the novel of the identical name, Smith stars as Robert Neville, a US Army virologist who lives in New York City after a virus has wholly wiped out humanity. The virus was reckoned to cure cancer, but instead, on the contrary, it turns everyone infected into mutant vampire-like beings. Anti-vaccine activists worldwide are conjuring up similar scenarios over the safety of the mRNA vaccines,tried for the first time in the history of humanity.

Anti-vaccination activists claim mRNA vaccines represent genetic manipulation as it intervenes directly with the inoculated person’s genes. They contend that any damage caused by mRNA vaccination will be irreversible and patients will have to live with consequences like Down Syndrome, Klinefelter Syndrome, Turner Syndrome etc. because the genetic defect is forever. Hence, they consider mRNA to be a crime.

At the moment, the greatest miracle and the most significant medical advance in the last 100 years appear to be the mRNA vaccines. The year 2020 will be remembered as the most unprecedented year for the medical world for having made a quantum leap from traditional vaccines to the genetic vaccines. This modern miracle is a testament to human ingenuity.

— The author is director, Directorate of Vigilance & Anti-Corruption (DVAC)

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