Learn more about the CDC-Funded AZ HEROES Study and the AZ HEROES Kids Study

The Arizona Healthcare, Emergency Response, and Other Essential workers Surveillance (AZ HEROES) Study is a two-year research project funded by the Centers for Disease Control and Prevention. The study will help us understand how long immunity to COVID-19 lasts, and whether individuals experience repeat infections. The AZ HEROES research team plans to enroll 4,000 health care workers, first responders, frontline workers and other essential workers as participants across Arizona. Half of the study participants will have been previously infected by COVID-19.

Study Objectives

1) To assess the incidence of asymptomatic and symptomatic re-infection in frontline workers in Arizona (healthcare personnel, first responders and other frontline and/or essential workers.)

2) To identify patterns of COVID-19 immunity over time in previously and newly infected individuals who test positive for COVID-19 antibodies.

3) To evaluate the effectiveness of COVID-19 vaccines in preventing SARS-CoV-2 infection and COVID-19 illness.


COVID-19 is caused by infection with the SARS-CoV-2 virus.  It is highly contagious and transmitted primarily through respiratory droplets. Those infected can experience serious illness and death, although some people will have no symptoms at all even though they can still transmit disease.  Health care workers, first responders, frontline workers and other essential workers are all at increased risk for COVID-19, given their exposure to the public and/or coworkers through work.  We need to learn more about COVID-19 risks in each of these groups.  We also need to determine how long immunity to COVID-19 lasts, or in other words, when a person can become infected again after repeat exposure toSARS-CoV-2, and how severe repeat infection will be.  This information is critical to being able to protect our workforce and to our understanding of this pandemic disease.


We are not currently enrolling participants. This CDC-funded study will help researchers learn more about SARS-CoV-2 infection in children and teenagers and how well the COVID-19 vaccine protects from infection.

Study Objectives

The purpose of this pediatric study is to learn the following:

  • Children’s risk for infection with COVID-19 and what affects their risk for infection
  • How well the COVID-19 vaccine protects children from SARS-CoV-2 infection and illness