Coronavirus vaccine: Challenges to overcome. In this article we will learn the complexities and challenges to overcome to produce a vaccine of Coronavirus amidst COVID-19 pandemic.
In December 2019, a new strain of corona virus(nCoV) causing severe respiratory illnesses identified in Wuhan, China. This was the beginning of this pandemic. This coronavirus (nCoV) has a much larger global spread than severe acute respiratory syndrome (SARS 2003) and the Middle East Respiratory Syndrome (MERS 2012). These earlier hCoVs were confirmed to have originated from bats and nCoV2019 is also suspected to.
- Do you have any idea what was the fastest vaccine ever developed? It was vaccine of mumps. It took four years to develop.
- Reports and analysis of cases indicates that coronaviruses do not tend to trigger long-lasting immunity.Researchers from Oxford University recently studied on a blood sample taken from recovered Covid-19 patients and found that levels of IgG antibodies which is responsible for longer-lasting immunity, became weak after few months.
- The genetic stability of the virus matters too. Some viruses like influenza, mutate so rapidly that vaccine developers have to release new formulations every year. Similarly, the rapid evolution of HIV is the reason we are still unable to develop a vaccine for the disease.
- The SARS-CoV-2 coronavirus seems fairly stable, but it is acquiring mutations too, slowly but it is, like all other viruses. Scientists have spotted some genetical changes in the virus’s protein “spikes”. If the mutation rate of the spike proteins becomes high, the antibodies produced by a vaccine will not be effective and might not combine with the virus to prevent infection.
Types of vaccines
- Live vaccines: Live vaccines are produced from weakened or attenuated form of the germ that causes a disease.
- Examples: measles, mumps, rubella, smallpox and chickenpox
- Inactivated vaccines: Inactivated vaccines are produced from a killed or inactive version of the germ that causes a disease.
- Examples: Flu, hepatitis A and rabies
Now let’s know – How are the Vaccines produced ?
Step 1:Characteristics of the virus are determined and potential vaccines are analyzed repeatedly to check whether it is safe and can trigger the right parts of the body’s immunity, without any damage or serious side-effects.
Step 2: Pre-clinical animal testing of potential vaccines is done validating the right biological model for the virus.This testing is done under strict lab guidelines and generally takes five to six months.
Step 3: If a vaccine is found to be safe and effective, it will need to pass the necessary regulatory approvals.
Step 4: If the vaccines successfully pass pre-clinical testing, it is further used by other institutions with the capacity to run human trials. The human trial consistsfour phases.
- Phase one involves introduction of the vaccine into human population
- Phase two is the observation stage of immunogenic and toxicity results
- Phase three deals with the monitoring toxicity results in large scale
- Phase four is the data collection stage on adverse effects and long-term immunity
Step 5: The vaccine also passes through trials of many cost-effective ways for commercial production before the final vaccine is made available for the patients around the world.
Major challenges to overcome for corona virus vaccine
- Ensuring vaccine safety: Several vaccines for COVID-19 have been tested in animals but most of the didn’t prevent infection though it improved the animal’s immunity. Some vaccines also caused lung damage. Still A COVID-19 vaccine is needed to be tested in human models for its safety.
- Long-term protection: Infection and re-infection with the same virus is being tested but as it is mentioned earlier the antibodies are falling weak after few months.
- Protection of older people: Older people are at higher risk of severe COVID-19. But clinical challenge is the older people usually don’t respond to vaccines as well as younger people.
Now the most vital question: Is the virus here to stay with us?
The answer is yes, definitely it will stay with us for longer until a vaccine is produced. The virus seems very hard to conquer with a vaccine that lasts for years.
Some scientists are also hopeful that there is a possibility that coronavirus infection might end up with mild infection and people will get a minor cold related symptoms thereafter.
Scientists are still at sea about the destiny of the virus and pandemic and scientists and pharmaceutical companies from different countries are burning the candle at both ends to formulate the vaccine of COVID-19.The time will answer whether the corona virus will disappear or become less virulent or become more deadly. We do not know.