Almost a year after “ground zero”, the first COVID-19 fatality in Guyana on March 11, 2020, Guyana received 3000 doses of the Oxford AstraZeneca vaccine courtesy of our Caricom colleague Barbados on February 11, 2021. This, in and of itself, was a remarkable achievement since up to this time, vaccines took much longer to be created – much less to reach a backwater like Guyana. It was a reflection of the seriousness in which COVID-19 had to be taken as the pandemic took its toll across the world, especially in the developed countries and millions died. Presently, 2.65 million have perished worldwide and 207 in Guyana.
The vaccines from Barbados, which had been donated by India, were immediately inserted into our local programme that had been created by the Ministry of Health (M0H) in the preceding months as vaccination programmes in several countries with access to vaccines were unfurled. The main planks of the vaccination programme were the “cold chain” demands that necessitated the vaccines be refrigerated, stored and transported; training medical personnel to administer the shots; establishing vaccination centres and finally, the scheduling of the vaccination for different cohorts.
In Guyana, as with the rest of the world, it was decided to begin with the health workers who are in the forefront, dealing with the afflicted even before they might have been diagnosed. In a sense, these health workers were also volunteering to be guinea pigs since there was great scepticism about the vaccines. These would be followed by the elderly (over 60) and individuals with co-morbid conditions.
Presently, more than 150 vaccines are at various stages of development and about a half-dozen deployed. Most of the countries creating the vaccines have rigorous protocols before approving them for use, but because of the crisis as mentioned before, much have been truncated, and not surprisingly, creating some scepticism.
A second variable is that there are four categories of vaccines in clinical trials: WHOLE VIRUS, PROTEIN SUBUNIT, VIRAL VECTOR and NUCLEIC ACID (RNA AND DNA). Some of them try to smuggle the antigen that fight off the COVID-19 virus into the body, others use the body’s own cells to make the viral antigen. The AstraZeneca vaccine, of which we have since received 80,000 more directly from India, uses a viral vector – a harmless cold virus common to chimpanzees as a transport mechanism. The vaccine transports the surface protein of SARS-CoV-2 to human cells, which begin to churn out the spike protein and neutralise the virus.
We will soon receive 5000 doses of the Russian developed Sputnik V, which uses the same mechanism as Oxford’s AstraZeneca. The researchers, however, developed their vaccine from adenoviruses, a kind of virus that causes colds. They added the gene for the coronavirus spike protein gene to two types of adenoviruses and engineered them so they could invade cells but not replicate.
We have also received 20,000 doses of the SinoPharm vaccine from China. This uses the traditional mechanism of deploying the whole inactive virus into the body as had been done with smallpox. The main idea behind classical vaccination is to introduce into the human or animal subject a virus in a harmless form so as to trigger the immune response, or the body’s defence mechanism. This then generates antibodies that subsequently bind to the virus when it tries to infect the human or animal with the disease.
Moderna and Pfizer/BioNTech, which have not been made available in Guyana, are both a new type of vaccine made from messenger RNA. The Pfizer vaccine, however, needs to be stored at extremely low temperatures -94 degrees Fahrenheit and it consequently is not optimal for Guyana. The Moderna variant uses regular refrigeration.
In the meantime, the MoH has diligently but carefully extended the vaccination rollout to ensure the kinks are worked out. Presently, there have been no reports of any adverse effects to the vaccines administered, outside of the expected low fever due to the body producing antigens, and mild pain at the point of vaccination.
