What are the Sinopharm and Sinovac vaccines? from buzai232's blog

What are the Sinopharm and Sinovac vaccines?

Last weekend, China reached a milestone of having administered more than one billion doses of its homegrown COVID-19 vaccines, the majority of which were developed by local companies Sinovac and Sinopharm.To get more news about sinopharm update, you can visit shine news official website.

What’s more, hundreds of millions of doses of these vaccines have been shipped to more than 80 countries worldwide.Sinopharm was given emergency approval by the World Health Organization (WHO) in May this year, and Sinovac in June.

But what do we know about these vaccines? How do they work, are they safe, and how effective are they in the real world?Both are inactivated virus vaccines. This means they’re made from viral particles produced in a lab, which are then inactivated so they can’t infect you with COVID-19. Many other vaccines use similar platforms, including injectable polio, Hepatitis A and flu vaccines.

Both companies use similar technology, and the vaccines are mixed with an adjuvant, which is a substance added to vaccines to stimulate a stronger immune response.

The vaccines contain many proteins the immune system can respond to, stimulating the production of antibodies to fight COVID-19.Side-effects common after most other COVID-19 vaccines, such as fever and fatigue, were found to be uncommon after Sinovac or Sinopharm.

Once vaccines are approved and being used in large populations, they’re continuously monitored for very rare side effects. No significant safety concerns have been identified amid Sinovac’s rollout in China, Brazil, Indonesia and Chile.

In saying that, there were very low numbers of adverse events identified overall, which would suggest substantial under-reporting.For example, there were only 49 serious adverse events reported following 35.8 million Sinovac doses administered in China.

In a population of that size, we’d expect to see a larger number of illnesses and deaths recorded in the few weeks after vaccination just by coincidence alone, even if not causally related to the vaccine.

Only 79 people reported mostly mild adverse events following 1.1 million doses of Sinopharm in China, much lower than usual rates of adverse event reporting following immunisation.

A potential side effect of particular concern is what’s called “vaccine-associated enhanced disease”. This is a very rare side effect of some other vaccines which use a similar “inactivated” technology to the Sinopharm and Sinovac vaccines.

It occurs when a vaccinated person is exposed to the virus and develops a serious inflammatory condition, and results in them getting more severe symptoms than they would have without the vaccination.

This hasn’t been reported for these vaccines to date, although WHO recommends ongoing safety monitoring to identify any cases that occur.Sinovac’s efficacy at preventing symptomatic infection was 51% in Brazil, 67% in Chile, 65% in Indonesia, and 84% in Turkey. The differences in results may be due to different variants circulating in each country at the time and differences in the populations included in the studies.

Sinopharm’s efficacy in preventing symptomatic infection was 78% in UAE, Bahrain, Egypt and Jordan combined.

As with all the COVID-19 vaccines for which data are available, efficacy against the more severe outcomes is greater. Efficacy against hospitalisation for Sinovac in Chile, Brazil and Turkey was 85%, 100% and 100%, respectively.Data published in April from a large real world study in Chile suggests Sinovac is 67% effective in preventing symptomatic COVID-19 infection. It’s effectiveness against hospitalisation was 85%, ICU admission 89%, and death 80%.

However, it’s concerning there have been increases in infections in some countries where these vaccines have been extensively used, but detailed reports are not available.For example, Seychelles has fully vaccinated 68% of its population, mostly with Sinopharm and the remainder with AstraZeneca.

Seychelles has recently experienced a surge in cases, which suggests the herd immunity threshold may not have been reached. The exact threshold for this is unknown but is influenced by variants in circulation, the number of people vaccinated, and the effectiveness of the vaccines.

Detailed epidemiological studies are required to investigate this but news reports suggest 20% of those hospitalised and 37% of new active cases are fully vaccinated.