Covid-19 Vaccines: The Hope We've Been Waiting For
Updated: Mar 25, 2021
It has almost been a year since the World Health Organization made the decision to classify the coronavirus outbreak as a pandemic back in the 11th of March, 2020. Since then, there have been a total of 111 million reported cases of the infection, and 2.46 million deaths globally. Due to the devastating impact the pandemic brought to every country’s economy, the development of a vaccine was of utmost importance.
Developing a vaccine takes about 10-15 years on average, depending on the specific virus. However, not even a year into the classification of this outbreak as a pandemic, companies such as Pfizer and Moderna were already able to develop a vaccine for it. This makes it the fastest vaccine to have ever been developed, beating the previous record of the vaccine for mumps that took 4 years to make.
Quick Overview of Vaccines
There are different ways to make a vaccine. There’s the genetic approach: nucleic acid vaccines. A section of the virus’ genetic material gives instructions that help our cells produce antibodies. Before the vaccines engineered for COVID-19, no nucleic acid vaccines had been approved for human use although some were undergoing human trials.
There is also the protein sub-unit approach. The “crowns” or spike protein are used in the vaccine to help trigger a response from the immune system which helps people build up antigens.
There is the whole virus approach. A vaccine may contain a weakened, but living form of the virus that is harmless to help the immune system respond properly. Sometimes, the virus is killed or inactivated and is used in the vaccine so that the immune system learns how to fight the virus.
Finally, the virus vector approach usually contains more common or safe viruses. The common virus is used to deliver a small part of the germ of interest into the body so that it can immunize itself; a commonly used virus in this vaccine is the adenovirus which causes the common cold.
There are several companies that are manufacturing vaccines. First is the Pfizer-BioNTech vaccine. A mRNA (Messenger Ribonucleic Acid) vaccine uses the genetic material of the virus to boost immunity against it; it is diluted in 0.9 sodium chloride. Based on evidence from clinical trials on about 43,000 people with no former evidence of infection, the vaccine is 94% effective at preventing lab-confirmed Covid-19 in symptomatic patients and 97% effective at preventing Covid-19 in asymptomatic patients. The Pfizer-BioNTech vaccine can be given to those 16 years of age and older. The shots are administered in the deltoid muscle (in the shoulder); a full dose is given in 2 shots that must be provided 21 days apart from each other. A patient can have an allergic reaction within 4 hours of being vaccinated, symptoms include hives, swelling and wheezing or difficulty in breathing. Being vaccinated can also result in some soreness around the injection site, tiredness, chills, headaches and fever; fewer people experience muscle pain, joint pain, nausea and swollen lymph nodes but it is still a possibility.
Moderna’s vaccine from the US is also a mRNA type; it has no diluent. They ran several trials with 30,000 participants and their vaccine and found that it was 94.1% effective at preventing Covid-19 in people with no previous infection. This vaccine can be given to 18 year-olds and above. Shots are administered in the deltoid muscle; a full dose is 2 shots and the second shot must be given 28 days after the first. The vaccine can have some side effects such as swelling where the vaccine was injected and chills. Some more severe side effects such as fever begin after the second shot but are usually resolved within a week.
The Oxford-AstraZeneca vaccine from the UK, a virus vector vaccine that contains an adenovirus with spike proteins in it. Data from clinical trials with over 24,000 participants in the UK, Brazil and South Africa shows that the vaccine is 70.4% effective on average and 62% effective against preventing COVID-19 when administered in two standard doses. Some common side effects are chills, headaches, fatigue, joint pain, muscle aching and nausea. More uncommon side effects are dizziness, abdominal pain, decreased appetite, enlarged lymph nodes, excessive sweating and itching or rashes. There were a few rare cases in which the vaccination was associated with inflammation of the nervous system which can cause numbness, pins and needles or loss of feeling.
The Sputnik V vaccine by Gamaleya in Russia is a viral vector type. The virus in the vaccine has its genetic code removed so that it cannot replicate. Sputnik V is 91.6% effective and 100% effective at preventing serious cases of Covid-19. 15% of vaccinated people experienced weakness, muscle pain and occasional fever.
4. CanSino Vaccine
CanSino’s vaccine in China is a non replicating viral vector like the Sputnik V. It has an efficacy rate of 65.7% and 90.98% at preventing severe cases of Covid-19; the vaccine can be given to those 18 years old and up. 72% of those who received a low dose of the vaccine and 74% of those that got a high dose experienced fever, fatigue and pain at the injection site.
The Covishield vaccine by the Serum Institute of India is a weakened adenovirus modified to be similar to SARS-Cov-2. The vaccine is 70-90% effective, 70% at the half dose and 90% at the full dose. Side effects include swelling and itching at the injection site plus fatigue, chills, headaches, nausea, slight fever, muscles aching and joint pain.
Covaxin by Bharat Biotech, an inactivated whole virus type. This vaccine is at least 60% effective; it is administered in 2 doses 14 days apart. The side effects can be allergic reactions like difficulty in breathing, swelling of face and throat, fast heartbeat, rashes all over, dizziness, nausea and body aching. Swelling, itching and redness are also expected at the injection site.
Sinovac is a whole virus vaccine being manufactured by the Chinese company, Sinovac Biotech. It is 65.3 - 91.25% effective at preventing Covid-19/ In an interview of Mr. Yin of Sinovac, he stated that “Some [who took the vaccine] only showed minor fatigue or discomfort… no more than 5% [of the 1,000 participants].”
A Human Feat
Undoubtedly, the making of the COVID-19 vaccine will go down as one of the most historic medical feats humanity has achieved, being the fastest vaccine to have been developed. With that being said, it still needs further development and refining to be safe for younger children. The distribution of this vaccine will hopefully help and contribute to the country’s economy finally picking back up after the recession that it experienced during this pandemic.
Note: Please keep in mind information is subject to change over time, use this information at your own discretion
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