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Shasta County's Response to Local Emergencies

Vaccine Frequently Asked Questions

We know you have many questions about the vaccines and how they affect you and your loved ones. Below is a collection of common questions. We'll continue to add to the list as we receive questions from the community.

Do you have unanswered questions?

Call 211 for frequently asked questions about coronavirus, or email


As a health department, it is our goal to ensure everyone in the county is safe and healthy. The care and safety of the public is always our top priority. As with any vaccine, Shasta County will not distribute a COVID-19 vaccine unless the U.S. Food and Drug Administration (FDA) has determined it is safe and effective. The governments' high-tech, space-age name for the vaccine development program - Operation Warp Speed - may have inadvertently increased concerns about the safety of future vaccines. However, the FDA oversees and regulates vaccine quality, safety and effectiveness. The FDA says it is committed to expediting the development of COVID-19 vaccines, but not at the expense of sound science and decision making. It will not jeopardize the public's trust in the science-based, independent review of any vaccine.

After the FDA determines a COVID-19 vaccine is safe, the Advisory Committee of Immunization Practices (ACIP) reviews the clinical trial data and provides advice and guidance to the Centers for Disease Control.

In addition to federal review, California has formed a panel of public health and immunization experts—the Scientific Safety Review Workgroup—to review the efficacy and safety data of COVID-19 vaccine candidates. Neighboring states Washington, Oregon and Nevada are joining California’s effort to conduct independent reviews to ensure the safety and efficacy of any vaccine approved by the FDA.

The vaccines will continue to be monitored even after the vaccines reach the general public. National vaccine safety monitoring systems watch for rare side effects (called adverse events) that may not have been seen in clinical trials. If the symptoms are true safety concerns, the guidelines for the vaccine will be changed. This monitoring ensures that the vaccine’s benefits continue to outweigh the risks. 

Visit the CDC for more information on the Safety of COVID-19 Vaccines and to report unusual side effects following any vaccination (see links under "Existing Safety Monitoring Systems").  

Below is a summary of the benefits of getting a COVID-19 vaccination. Click here for more benefits.

  1. Prevent serious illness:  Based on what we know about vaccines for other diseases, a COVID-19 vaccine may help keep you from getting seriously ill even if you do get COVID-19. It will also help protect people around you, particularly people at increased risk for severe illness from COVID-19.
  2. Help stop the pandemic: Scientists estimate that to control COVID-19, about 7 or 8 of every 10 people will need to be vaccinated to control the virus. Given that the U.S. population is more than 330 million people, this means that almost 250 million will need to receive the vaccination to reach this goal.
  3. Build protection safely: The risk of severe illness and death from COVID-19 far outweighs any benefits of natural immunity. COVID-19 can have serious, life-threatening complications, and there is no ways to know how COVID-19 will affect you. The vaccination will help protect you by creating an antibody response without having to experience sickness.

One might expect to have similar side effects as with other immunizations, such as fatigue, headache, body aches, soreness at the site of injection and even some fever. These are considered normal immune responses to the vaccine and are actually your body’s natural response in building immunity to this unwanted invader.

However, there’s a possibility that rare side effects (called adverse events) may emerge as millions of people are given the vaccine. Unusual side effects should be reported to one of the nation’s safety monitoring systems for the general public, military members, veterans and tribal nations. If the symptoms are true safety concerns, the guidelines for the vaccine will be changed. This monitoring ensures that the vaccine’s benefits continue to outweigh the risks.

Learn about the difference between a vaccine side effect and an adverse event

We will learn more about side effects associated with each individual vaccine as the clinical trial data is reviewed during the approval process. All agree that it’s important to be informed of the vaccine’s benefits and risks. The data will be of interest to California’s Scientific Safety Review Workgroup, as it will conduct an independent review to ensure the safety and efficacy of any vaccine approved by the FDA.

After a vaccine is authorized or approved for use, many vaccine safety monitoring systems watch for adverse events (possible side effects). This continued monitoring can pick up on adverse events that may not have been seen in clinical trials.

There's a possibility that rare side effects may emerge as millions of people are given the vaccine. The Vaccine Adverse Event Reporting System (VAERS), a national vaccine safety surveillance program, collects and analyzes adverse events associated with U.S. licensed vaccines. Anyone can submit a report to VAERS, including providers, patients and parents.

Providers: Under the Emergency Use Authorization, providers are required to report serious negative side effects to VAERS or to the vaccine’s manufacturer per its Fact Sheet.

Public: The public should report unusual side effects to one of the nation's safety monitoring systems for the general public, military members, veterans and tribal nations. Or, call VAERS toll-free number at 1-800-822-7967.

For an additional layer of safety monitoring, the CDC has introduced the V-safe app. It is a smartphone-based health checker for people who receive COVID-19 vaccines. V-safe uses text messaging and web surveys to:

The app allows the CDC and FDA to evaluate COVID-19 vaccine safety in real time and make sure vaccines are as safe as possible.

At first, COVID-19 vaccines may not be recommended for children. In early clinical trials for various COVID-19 vaccines, only non-pregnant adults participated. However, clinical trials continue to expand those recruited to participate, including children. The groups recommended to receive the vaccines could change in the future.


Public vaccination sites will be shared as they become available.

Hospitals, skilled nursing facilities and assisted living facilities were encouraged to enroll with the federal vaccination program, the COVIDReadi System. This system allows enrollees to receive and administer COVID-19 vaccines for their staff members. Clinics and pharmacies were also called upon to enroll as vaccine providers for the general public.

The first vaccines made available to Shasta County will be the two-dose vaccines. The two-dose vaccines are spaced a few weeks apart, and the second shot is required to be effective.

There is a lag of a few weeks between the time of receiving the vaccine to the time the body produces a robust immune response. For some vaccines, minimal immunity may begin approximately 2 weeks after the first dose, but maximum immunity may not be achieved for 2 to 4 weeks after the second dose. Depending on the dosing regimen and schedule, it may take as long as 6 to 8 weeks to get the full benefits of the vaccine. Therefore, it is possible that a person could be infected by COVID-19 just before or just after vaccination and then get sick because the vaccine did not have enough time to provide full protection.

Yes. The CDC recommends that you get vaccinated even if you have already had COVID-19, because you can catch it more than once. While you may have some short-term antibody protection after recovering from COVID-19, we don't know how long this protection will last. Since people who have had COVID-19 are assumed to have some level of immunity, they may be directed to wait for 90 days before getting the vaccine.

Vaccinations benefit both the person being vaccinated and the community at large. A community is sufficiently vaccinated when it reaches herd immunity. Herd immunity is a term used to describe when enough people have protection—either from previous infection or vaccination—that it is unlikely a virus or bacteria can spread within the community even if some people don’t have any protection themselves.

The percentage of people who need to have protection to achieve herd immunity varies by disease. Experts don’t yet know what percentage of people would need to get vaccinated to achieve herd immunity to COVID-19. However, the World Health Organization and Johns Hopkins Center have suggested at least a 70% vaccine coverage rate to reach population immunity through vaccination.

Respiratory infections can be particularly difficult to block completely with vaccines. It would be a mistake to assume vaccination alone can suppress a pandemic.

There is not enough information currently available to say when CDC will stop recommending that people wear masks and avoid close contact with others to prevent the spread COVID-19. Experts need to understand more about the protection that COVID-19 vaccines provide before making that decision. Other factors, including how many people get vaccinated and how the virus is spreading in communities, will also affect this decision.

Cost to the individual will not be an obstacle to getting vaccinated against COVID-19. Vaccine doses purchased with taxpayer dollars will be given to the public at no cost—regardless of insurance status.

Providers, however, can charge for administering the vaccine, which insurance would cover. Providers can get this fee reimbursed by the patient’s public or private insurance company or, for uninsured patients, by the Health Resources and Services Administration’s Provider Relief Fund.

Public Health strongly recommends the COVID-19 vaccine to help protect yourself, your family and your community from COVID-19 infections. However, choosing to accept or decline the vaccine is a personal choice.

Planning & Development

An Emergency Use Authorization (EUA) is an authority granted to the Food and Drug Administration (FDA) to allow the use of unapproved medical products, or unapproved uses of approved medical products, to diagnose, treat or prevent serious or life-threatening diseases during a public health emergency, such as COVID-19 (watch video).

The FDA evaluates an EUA request for a medical product and reviews the scientific evidence to determine whether it meets legal standards.

All vaccines aim to expose the body to an antigen that won’t cause disease but will provoke an immune response that can block or kill the virus if a person becomes infected. At least eight types are being tried against the coronavirus, and they rely on different viruses or viral parts.

Traditional vaccine development is sequential, with one step not starting until the previous step was complete. However, due to the urgency of the pandemic, the government’s vaccine process was accelerated by Operation Warp Speed. The accelerated vaccine development has multiple activities (development, trials and manufacturing) work in parallel and the activities overlap on the timeline. This method shaved months off the schedule for delivery of vaccines.  

To compare the typical process with the accelerated process, visit Operation Warp Speed.

For more general information, visit How Vaccines Are Developed.

It will take time for the vaccine to be available to everyone. But the goal is for everyone who wants a vaccine to be able to get a vaccine.

Since it will take several months to produce enough vaccinations for the U.S. population, the COVID-19 Vaccination Program will require a phased approach. The California Department of Public Health is working with the Centers for Disease Control to roll out the COVID-19 Vaccination Program in California. The program’s phases are still being determined at this time. The Shasta County Public Health Department will keep the community posted as each phase is determined.

Allocation is directed by federal, state and county guidance.

The federal Advisory Committee on Immunization Practices (ACIP) within the Centers for Disease Control and Prevention (CDC) provides advice and guidance on vaccine-preventable diseases.

On the state level, California refers to the ACIP’s ethical vaccine recommendations. Accordingly, California health officials appointed more than 65 advocacy, labor and business organizations to a new Community Vaccine Advisory Committee to ensure that the vaccine is distributed equitably. The committee remains mindful of our most vulnerable populations, as not to undermine efforts in controlling this pandemic.

To address the efficacy and safety of COVID-19 vaccine candidates, California formed a panel of public health and immunization experts—the Scientific Safety Review Workgroup. Neighboring states Washington, Oregon and Nevada are joining California’s effort to conduct independent reviews of any vaccine approved by the FDA.

Building on the state’s workgroup, California gathered experts from various fields—immunization, geriatrics, ethics, epidemiology, health equity and pharmacy practices—to form the COVID-19 Drafting Guidelines Workgroup. This workgroup developed California-specific guidance for the prioritization and allocation of a COVID-19 vaccine. The guidance is based on the framework for equitable allocation by National Academies of Sciences, Engineering, and Medicine (NASEM), and the Centers for Disease Control and Prevention (CDC). The state’s distribution plan will guide counties, which will oversee on-the-ground coordination.

Locally, Shasta County is closely monitoring the progress of the vaccine and developing guidelines for distribution depending on the number of doses we receive over the coming weeks and months. The Health and Human Services Agency created a task force of stakeholders to determine how the national and state recommendations will be applied to our vaccination plans.  

The California Department of Public Health is working with local health departments to plan for and distribute COVID-19 vaccines. Some types of vaccines require ultra-cold freezers and are delivered in large quantities. Shasta County Public Health has acquired an ultra-cold freezer and is also working with other North State providers that can properly maintain and administer COVID-19 vaccine as well as meet additional federal and state requirements.