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Coronavirus Guide

Information for health professionals and the public in the Las Vegas Valley
This page is no longer being updated. Please refer to the Home Page for the latest information.

About this Page

Welcome to the COVID-19 Vaccine Information Page

This guide is written at a 4th- to 5th-grade reading level.

It will be easy to read for people with low English reading abilities.

It presents scientific ideas in a way that is easy to understand.

Why get the vaccine?

Why should I get the vaccine?

  • It helps protect you from getting sick with COVID-19.
  • It helps protect the people around you from getting sick.
  • You can stay safe from lung, heart, and other bad outcomes from getting sick with COVID-19.
  • You will be immune longer than if you had COVID-19.
  • You will help end the pandemic sooner.


Watch the video below for more on why you should get vaccinated:


How well do the vaccines work?

  • The Moderna and Pfizer vaccines are 94% to 95% effective.
    • This means 94 or 95 out of 100 people who get the vaccine will not get very sick if they come in contact with the coronavirus.
  • A vaccine protects you from being very ill. You might still get COVID-19, but you will have fewer symptoms and get better faster.


Why do I need two shots?

  • Both Pfizer and Moderna vaccines have two doses. This helps your body create a strong immune response to the coronavirus.
  • After one dose you are only 50% protected from illness. After two doses you are 95% protected.


Should I get a third shot/booster?

  • Yes. Research shows the vaccines begin to lose their protective strength after 6 months.
  • Everyone 18 years and older should get a booster dose of either mRNA vaccine 5 months after their 2nd dose of either mRNA vaccine, or after their Janssen/J&J vaccine.
  • Teens aged 12-17 should get a booster shot of Pfizer-NBioTech 5 months after their 2nd dose of Pfizer-NBioTech.

How do the vaccines work?

imae of 4 vials labeled coronavirus vaccine on a table next to a syringe. The Pfizer logo is on the wall behind the vials.


What is in the vaccines?

  • The vaccines don’t have any coronavirus in them.
  • They have mRNA, which stands for messenger RNA.
  • The other ingredients are lipids, salts, sugar, acids, and acid stabilizers.
  • Lipids help the mRNA stay together and enter your cells.
  • The salt and acid ingredients help the vaccine match your own body's acid levels.
  • Sugar helps the mRNA keep its shape when the vaccine freezes.
  • For more complex information you can read the fact sheets.


How do the vaccines work?

  • The part of both the Pfizer and Moderna vaccine that makes them work is mRNA.
  • The messages from mRNA tell your immune system how to work. It teaches your cells to make spike protein. This protein is on the virus that causes COVID-19.
  • Your immune cells fight off the spike protein and they remember how to do it.
  • If you catch the virus after getting the vaccine your immune system stops it.
  • This is what protects you from getting very sick in the future.
  • The vaccines are frozen to stop the mRNA from breaking down during travel and storage.


The video below explains how mRNA vaccines work:

How safe are the vaccines?

How safe are the vaccines?

  • Both vaccines are safe and approved by the Food & Drug Administration.
    • Researchers worked very fast to make the vaccines.
    • They completed all the usual tests needed for vaccines.
    • They also gave the vaccines to tens of thousands of people.
    • That is why we are confident they are safe and that they work.
  • A very small number of people have bad reactions to vaccines.
    • If you have had an allergic reaction to a vaccine before, speak to your doctor or pharmacist about safety.
    • If you are pregnant or breastfeeding, speak to your doctor before getting the vaccine.
    • Only the bad reactions get reported. This makes it seem like the vaccine is more dangerous than it is. 
    • Thousands of people have had the vaccine without a bad reaction.
    • Getting vaccinated is much less risky than getting COVID-19.
  • mRNA vaccines do not change your genes.
    • Your body destroys the mRNA from the vaccine within a few hours.
    • It does not stay in your body and can't change your DNA.


Watch the video below to learn more about vaccine testing:


Does the vaccine have side effects?

  • Most vaccines can cause mild side effects.
  • For the first dose of the COVID-19 vaccine, you might have some redness and swelling at the spot they gave you the shot.
    • Your arm might also feel sore a few hours later and last for about a day.
  • The second dose of the vaccine might make you feel like you have a cold.
    • This goes away in about a day and you can take over-the-counter medicine to help relieve symptoms.
    • You might experience:
      • Fever
      • Headache
      • Fatigue
      • Muscle pain
      • Joint pain
      • Chills
      • Upset stomach
    • A severe allergic reaction is very rare.
      • An allergic reaction would happen a few minutes to an hour after getting the vaccine.
      • Call 9-1-1 if you experience the following symptoms:
        • Difficulty breathing
        • Swelling of your face and throat
        • A fast heartbeat
        • A bad rash all over your body
        • Dizziness and weakness
    • If you have side effects from the vaccine, you can report them.
      • You can use v-safe, a smartphone app from the Centers for Disease Control and Prevention (CDC).
        • The app collects information about side effects and reminds you to take your second dose.
      • You can also report side effects to the FDA/CDC Vaccine Adverse Event Reporting System (VAERS).
  • Getting a headache or fever or feeling tired and achy for a day or 2 is actually a good thing! These are signs that the vaccine is working.

When & Where to Get the Vaccine

When can I get a vaccine?

  • Vaccines are currently being given to all eligible Nevadans.

Where can I get a vaccine?

image of gloved hands using a syringe to pull vaccine from out of a vial

What about the Johnson & Johnson vaccine?

What are the risks?

  • Most people who get the J&J vaccine will have only mild side effects.
  • Go to a doctor right away if you had the vaccine in the past 3 weeks and have any of these symptoms:
    • severe headache

    • backache

    • new neurologic symptoms

    • severe abdominal pain

    • shortness of breath

    • leg swelling

    • tiny red spots on the skin (petechiae)

    • new or easy bruising


How does it work?

  • A virus that does not cause COVID-19 enters your cells
  • Information stored in the virus tells your cells to make a very small part of the COVID-19 virus called a spike protein.
  • The spike protein is attacked by your immune cells.
  • Your immune cells learn and remember how to fight off the virus that causes COVID-19.


How well does it work?

  • 66.3% of people who got the vaccine were protected from getting sick with COVID-19 after 2 weeks.

  • 100% of those who did get sick did not have to go to the hospital.

  • The Janssen/J&J vaccine is less effective than the mRNA vaccines.


J&J Vaccine Pause

On April 13, 2021 the CDC and FDA paused giving J&J vaccines. They allowed their use again starting April 25th, 2021.

  • The pause was because 6 people out of 7 million developed blood clots after taking the vaccine.

    • Clots are solid clumps of cells that block blood flow in the body.

    • It is still not known if the vaccine caused the clots.

    • All people who had clots were female and 18 to 48 years old.

    • The reaction happened between 6 and 13 days after getting the J&J vaccine.

  • The CDC and FDA determined the benefits of giving the vaccine were much more important than the risk of blood clots.


To read more about the Johnson & Johnson vaccine, visit the CDC website here:

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