Since the beginning of the Covid-19 pandemic, the world has been looking for the viable alternative to fight infection and eradicate the deadly disease that claimed millions of lives in more than a year.
Taking physical distance and masks helped, but it was not palliative enough.
The challenge of science is to reduce infections and fight this coronavirus through vaccines, which several countries have already started to administer and the Dominican Republic still does not have a specific start date, although the government confirmed on Monday, February 15. . it will announce the vaccination plan.
As of December 2020, more than 200 vaccine candidates were in development, 7 of which are already circulating in the world, although they are used in an emergency.
The Dominican Republic will receive vaccines from Pfizer, AstraZeneca and Sinovac, President Luis Abinader announced on Thursday. How effective are these vaccinations?
Pfizer-BioNTech
The BNT162b2 vaccine from Pfizer and BioNTech is 95% effective, the highest rate of more than 30 vaccines in the world.
Clinical trials have now completed Phase 3 and it is recommended for use in people 16 years of age or older. However, its use is not recommended in people who have reacted with allergies to polyethylene glycol (PEG) and polysorbate.
Although two doses are required 21 days apart, the second injection should not be given if the patient has had a severe or immediate allergic reaction to the first dose.
It must be refrigerated to -70ºC and can be frozen for five days.
Its use has been approved by the United States, United Kingdom, European Union, World Health Organization and other countries.
Chills, fatigue and headaches are some of the side effects that occur within 7 days of vaccination.
The Dominican government signed a mid-term agreement with this pharmaceutical company to guarantee 7.9 million doses of the BNT162b2 vaccine.
The agreement was signed by the Minister of Health, Dr. Plutarco Arias, representing the Dominican Republic.
Prior to this agreement, President Luis Abinader reported on Friday, Jan. 8, that they expected to receive about 25,000 doses of the vaccine manufactured by the pharmaceutical company Pfizer during that month, but this delivery has not been made.
Pfizer and other pharmaceutical companies have been delayed in delivering vaccines to contracted countries.
Modern (United States)
With 94.1% efficacy and phase 3 clinical trials completed, the vaccine developed by the pharmaceutical company Moderna is the second with the highest efficacy of the vaccines announced in the world, as well as the second approved by the European Medicines Agency (EMA).
This vaccine should be stored for 30 days, but can be kept refrigerated at -20 degrees Celsius for up to six months.
For effective use, two applications must be submitted with a difference of 28 days between each. However, in late January, the pharmaceutical company announced that the effectiveness to generate antibodies against the South African version is lower than for the original virus, so they are working on a new vaccine that may be added to the current treatment of the two doses. .
The United States, Canada, the United Kingdom, Israel, Switzerland and the countries that are part of the European Union are some of those already using Moderna’s vaccine, developed in collaboration with the National Institutes of Health in the United States and authorized by the World Health Organization. Health.
Additionally, the U.S. Food and Drug Administration (FDA) has approved Moderna’s covid-19 vaccine for emergency use in that country.
Sputnik V.
The Russian Sputnik V vaccine, developed by the Gamaleya Research Institute of Russia, is one of three vaccines in the world with an efficacy of more than 90%.
Like those produced by Johnson & Johnson and AstraZeneca, Sputnik V is a viral vector, as opposed to using a different adenovirus in each dose.
According to Gamaleya’s study, the efficacy against Covid-19 of this vaccine, named after the first Soviet space satellite, is 91.6%, after demonstrating high immunogenicity and safety in phase III clinical studies.
Contrary to what AstraZeneca experts believe, the research center assures that the effectiveness of the vaccine for the elderly was 91.8% and was not statistically different from that of the group of people aged 18 to 60 years.
This vaccine requires two doses three weeks apart.
“To ensure long-lasting immunity, Russian scientists have developed the new idea of using two different types of adenoviral vectors (rAd26 and rAd5) for the first and second dose of the vaccine, enhancing the immunizing effect,” explains . the vaccine website page.
As for storage, it must be refrigerated to -20 degrees Celsius.
Sputnik V is registered in about 15 countries, including Russia, Venezuela, Argentina, Bolivia, Belarus, Serbia, and Algeria.
Oxford AstraZeneca
The Dominican Republic and the Anglo-Swedish company AstraZeneca have signed a contract to acquire 10 million doses of the Covid-19 vaccine.
The technology used in AstraZeneca vaccines is a viral vector, that is, a harmless virus is made to contain the gene for the SARS-CoV-2 peak protein, which prepares the immune system to produce the SARS-CoV-2. virus. then infects the body.
The drugmaker reported an effectiveness of more than 70%. However, according to the data presented by the EMA, an efficacy of approximately 60% has been demonstrated in clinical studies.
The Covid-19 AstraZeneca vaccine is not currently recommended for use in children; In adults over 55 years old, WHO experts recently expressed suspicion about its efficacy in the elderly and the South African variant of the virus.
The AstraZeneca app has been co-developed with the University of Oxford and is licensed in nearly 50 countries, including the United Kingdom, India, Morocco, the European Union and several countries in Latin America.
Before storage, the vaccine must be refrigerated for at least six months at a temperature between 2 and 8 degrees Celsius.
Sinopharm
The technology of this vaccine consists of inactivated virus. The SARS-CoV-2 virus is rendered inert by a process that preserves the structure of the virus and cannot later reproduce, but generates an immune response in the body.
The vaccine, developed by the Chinese state drug Sinopharm and the Beijing Institute of Biological Products, has completed the final phase of clinical trials and has an efficacy rate of 79%. The lab has applied for regulatory approval for the injection, bringing it closer to China’s first vaccine approved for use by the general public.
Its use is permitted in China and some other countries, such as Hungary, Serbia, UAE, Bahrain, Seychelles, Egypt, Laos, and Morocco. The required doses are two, three-week intervals.
Like AstraZeneca, storage is 2 to 8 degrees Celsius.
Johnson & Johnson
Johnson & Johnson is a company known in the country for the baby care products they distribute, but they are also manufacturers of medical devices and pharmaceuticals, one of the most recent being a vaccine against Covid-19.
The technology used is a viral vector, the same as AstraZeneca and Sputnik V.
According to journalistic reports, the vaccine showed an efficacy of 66% with a rate of 85% when it comes to preventing severe pictures of the disease.
But the analysis of the data showed that the tests were more effective in the United States (72%) than in South Africa (57%), where a different strain of the virus predominates.
The company asked the FDA for permission to use this vaccine, to which the company announced that it will issue its advice in late February after reviewing data from clinical trials.
Some of the advantages of this drug are that it is a single dose and does not need to be stored in special freezers. In addition, it can remain frozen at -20 degrees Celsius for two years and refrigerated between 2 and 8 degrees Celsius for three months.
CoronaVac
CoronaVac is a COVID-19 vaccine developed by the Chinese pharmaceutical company Sinovac Biotech, a developer specializing in vaccines for hepatitis A and B, seasonal flu, swine flu and avian flu.
The efficacy of this vaccination is about 50% in preventing infections and 80% in hospital admission, according to Sinovac. These data are the result of clinical studies and tests conducted in Brazil and Indonesia during Phase 3.
Coronavac became the second coronavirus vaccine to be approved by China in early February and used in Indonesia, Brazil and Turkey.
According to France24, the CoronaVac needs two doses to be effective and requires standard refrigeration between 2 and 8 degrees Celsius.
On Thursday afternoon, President Luis Abinader announced the purchase of 768,000 new vaccines from Sinovac.
The president has not specified how much they will cost the Dominican Republic.
Unknown efficacy
Other vaccines in development include CureVac (Germany / USA) from messenger RNA and Novavax, developed in the United States with recombinant peak protein, but the efficacy of both is unknown.
Although the US pharmaceutical company Novavax reported in late January that they achieved 89.6% effectiveness during their clinical studies for the variant of the virus found in the UK.
Likewise, there is the vaccination Sanofi / GSK (France and United Kingdom) developed with recombinant protein. In early February, it was reported that after a disappointing phase 2 study, companies are testing a different antigen formulation and are now targeting production later this year.
Knowing more
Other vaccines
In addition to the above, there are other vaccines such as those from the Indian company Bharat Biotech, developed and authorized in their country of origin, whose phase 3 clinical trials have not yet been completed. These are the drugs Covishield and Covaxin.
MRNA technology
The two most effective vaccines according to the competent organizations and entities have in common that their development takes place with messenger RNA (mRNA) technology.
This form consists of the drug that teaches our cells to produce a protein that triggers an immune response in our body.
On their website, the Centers for Disease Control and Prevention (CDC) explain that this immune response, which produces antibodies, protects us from infection when the real virus enters our bodies.
It should be noted that these vaccines cannot cause COVID-19 and do not contain the live virus that causes COVID-19. Likewise, they do not affect or interact with our DNA in any way.