In Arizona, the eligibility to receive a COVID-19 vaccine has expanded to allow all individuals 16 years of age and older to receive a vaccine. The vaccination rates and vaccine availability are incredibly supportive of reducing COVID-19 cases and curbing the pandemic. How were the vaccines tested? What are the available vaccines in the US? How do they work? What are the expectations after receiving your immunization?
COVID-19 vaccine development has hastened to an unprecedented speed. Vaccine development for SARS-CoV-1 and Middle East respiratory syndrome coronavirus (MERS-CoV) paved the way for the speedy development of COVID-19 vaccines. There are four phases that a vaccine must complete before receiving approval. The phases of clinical trials are as follows:
- Preclinical trials
- Phase I clinical trials
- Phase II clinical trials
- Phase III clinical trials
Preclinical trials typically use animal models to observe the safety of vaccinations. In phase I clinical trials, the objective is to test the safety and measure the immune response to determine an effective dose. Phase II clinical trials expand to a greater number of participants to get more information on the safety and immune response. And finally, phase III clinical trials are designed to determine whether the vaccines prevent infection.
COVID-19 vaccines are being developed using several different platforms such as RNA (Pfizer and Moderna) and DNA vaccines. RNA vaccines were the first vaccines for SARS-CoV-2 to be produced and are a new approach to vaccination. Once administered, your cells utilize the RNA to create the famous SARS-CoV-2 spike protein, creating an immune response. The mRNA remains in the cell cytoplasm and does not enter into the nucleus. Vector vaccines (Janssen) use a modified virus to deliver a gene to make the spike protein. The vector virus cannot replicate or cause illness.
How mRNA vaccines work
Following your vaccine dose, side effects are common. They might include soreness to the arm, lymph node enlargement in the armpit, muscle aches, chills, fever, fatigue, and headache. These symptoms tend to be more common after the second dose and are typically limited to the first two days after vaccination. Allergic reactions have been minimal, with reactions occurring at rates of 4.5 events per million doses for the mRNA vaccines. For a list of the components in the COVID-19 vaccines click here CDC website.
A COVID infection might still occur in those who are vaccinated. It is suggested to continue preventive measures such as wearing a mask and using social distancing when in public or around unvaccinated individuals. The CDC has stated that it is reasonable for fully vaccinated individuals to gather indoors in small groups or visit unvaccinated members of a single household as long as they are not at risk for severe COVID-19 without masking or distancing. The CDC also allows waiving post-exposure quarantine requirements for fully vaccinated individuals in the community if they remain asymptomatic. Individuals are considered fully immunized once two weeks have elapsed following receipt of a complete vaccination series.
Here are some sites to help you get started in finding a vaccine site or appointment:
- World Health Organization