Comparison of CoronaVac Covid vaccines with others


IN THE previous article I looked at the comparison of Johnson and Johnson COVID-19 vaccine with Pfizer and Moderna.
In this article, I am looking at the Chinese-made COVID-19 vaccine, specifically CoronaVac. Sinovac, a Beijing-based biopharmaceutical company, is the producer of CoronaVac. As opposed to Pfizer and Moderna, which are mRNA-made, CoronaVac is made out of inactivated (killed) viral particles that expose human bodies’ immune system to the virus without risking a serious disease response.
However, like Pfizer and Moderna, CoronaVac also requires a person to take two doses at four weeks’ interval to develop the immunity against COVID-19. Like others, it is also given to people aged 18 years and above, although trials are still ongoing in children.
As someone once said, CoronaVac has similar advantages as Johnson and Johnson COVID-19 vaccine in that it can be stored in a standard refrigerator at two to eight degrees Celsius as opposed to Pfizer and Moderna vaccines, which require -70C and -20C storage, respectively.
The two to eight degrees Celsius storage works out well for developing countries, which would need to make adjustments to accommodate vaccines requiring special freezers of between -20C and -70C storage capacity.
At the moment, it is not easy to state exactly how effective CoronaVac is following the mixed results received in the recent past. At one point, when the vaccine was undergoing phase three trials in Turkey and Indonesia, the interim data showed that the vaccine was 91.25 percent and 65.3 percent effective, respectively.
However, later in January 2021, Brazilian researchers reported 50.4 percent effectiveness against preventing people from contracting COVID-19 contrary to the 78 percent earlier reported. Like in many other vaccines, this vaccine was also halted in November 2020 when one of the volunteers died.
Following some investigations, the trial resumed later as it was reported that the death of that volunteer was not linked to this vaccine. A 55-year-old woman took the vaccine on March 2, 2021 and died four days later.
Again, her death was not linked to CoronaVac as her autopsy report indicated that she had serious chronic diseases.
Among some of the main concerns is how effective these vaccines are against the coronavirus variant strains, which were detected in Britain, Brazil and South Africa, which seem to be more infectious than the earlier version of the coronavirus. Although the mRNA made vaccines (Pfizer and Moderna) seem to have scored a higher efficacy to prevent disease during their trials in 2020, researchers argue that this was before the COVID-19 variants were reported.
Like other COVID-19 vaccines, the possible side-effects include, but not limited to, pain or swelling at the injection site, headache, fatigue, nausea, diarrhoea, cough, chills, loss of appetite, abdominal pain, nasal congestion, fever, vomiting, spasms, dizziness, and drowsiness, etc.
CoronaVac vaccine received approval in July 2020 for emergency use in China. Many Asian countries, among them Malaysia, Philippines, Indonesia, Singapore and China, have been rolling out their mass vaccination using this vaccine.
Zimbabwe is among African countries that have begun using this vaccine for its mass vaccine roll-out. South Africa might be the next African country to go for CoronaVac once it is approved for emergency use as Sinovac is committed to supply five million doses to that country. Algeria is another African country that was reported to be expecting the first batch of CoronaVac in January 2021.
It is also reported that Brazil and Chile have already secured deals to procure the same vaccine. Turkey, the United Arab Emirates and Bahrain are among the Middle East nations that have also approved the emergency use of CoronaVac.
CoronaVac availability?
At the moment, there seems to be a limit on how much this vaccine can be produced. The Sinovac company intends to manufacture 300 million doses in one year.
This implies that these doses can only cater for 150 million people in a year, which is not even sufficient to meet the Chinese population demand.
Whichever the case, China has other firms that have also embarked on the production of the COVID-19 vaccine to meet the country’s demand.
Despite the high demand for COVID-19 vaccines, many African countries are likely to benefit from the Chinese-made vaccines as its leadership has pledged to set aside US$2 billion for the African continent.
As it goes here all the time, good luck to all of us.

The author is an Australia Awards scholar in master of public health, Monash University.

Facebook Feed