As the search for coronavirus treatment continues around the world, researchers are also working hard to develop vaccines that could prevent people from acquiring it. The questions many people ask is how close they are before they get a solution and whether it is possible to expect it soon.

Currently, 19 vaccines are undergoing tests in human clinical trials in various countries. Though some tests are in the second and third phases, people will still have to wait for many months before they know whether any of these vaccines will protect against coronavirus.

Scientists are also exploring an additional 130 vaccines, but they have not qualified for human clinical trials yet.

Types of Coronavirus Vaccines

For now, four types of vaccines are undergoing human clinical trials. They all have various means of triggering an individual’s immune system in response to the coronavirus and prevent future infection. The vaccines include:


These are vaccines that require a copy of coronavirus genetic material to develop the vaccine. They function by mimicking the natural infection of COVID-19 and trigger an individual’s immune system to create a response.

Viral vector

These vaccines do not contain the virus but slightly different weakened or dead genetic material from the virus. The human immune system can react to produce protection against the genetic material, which prevents an actual infection.

Protein subunit

These vaccines contain proteins retrieved from the coronavirus. When injected directly into the body, researchers believe they can create an immune reaction. These types of vaccines are currently in use for conditions such as hepatitis B, HPV, and shingles.

Weak or inactivated

When researchers use these vaccines, they inject a weak or inactivated form of the COVID-19 to cause the immune system to create antibodies against it. The antibodies act by recognizing the virus infection and then trigger a quick response against it.

What is the Period Required to Develop a Vaccine?

Developing a usable vaccine requires about 10 to 15 years and sometimes even longer. The reason is that vaccines pass through several research procedures and tests to ensure they are safe and perfect.

These stages involved are:

Exploratory stage

Scientists identify foundations associated with the virus or bacteria known as antigens that might create an immune response.

Preclinical stage

Researchers test the potential vaccine in cells and then in animals to determine if they can produce an immune response. Many vaccines fail to go past this stage since they do not trigger an immune response.

Clinical research stage

After passing the preclinical stage, the vaccines get submitted to an Investigational New Drug (IND) in the FDA. Once the FDA approves the submission, the drug passes through three phases of clinical trials on humans. These include:

  • Phase 1 clinical trial: It involves around 20 to 100 healthy adults for several months to observe its functions.
  • Phase 2 clinical trial: this test requires a larger group of people, where some may be at risk of acquiring the disease. This phase may require several months up to two years.
  • Phase 3 clinical trial: this test requires thousands of people to determine the vaccines’ safety for about one to four years.

Approval and licensing 

After the third clinical trial, the manufacturer submits a Biologics License Application (BLA) to the FDA for evaluating the safety and effectiveness of a vaccine and whether to approve it.

Post-license monitoring

The FDA further monitors and reviews the vaccines for purity and safety, including programs to submit problems encountered while in use.

In summary, as we wait for the research of the coronavirus vaccine, let’s remain optimistic that researchers will find its cure before the prolonged period of vaccine research elapses.