What Is the Gamma Variant?

What to know about this COVID-19 mutation, also known as the P.1 variant

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

Since the start of the COVID-19 pandemic, multiple variants of the virus have developed. One of these variants is P.1, which was discovered in four travelers from Brazil as they were screened at an airport in Japan in January 2021.

COVID-19 variant

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Where Gamma Has Spread

The P.1 variant, also known as the Gamma variant, has now spread to at least 68 countries worldwide, including the United States. It is the dominant strain of COVID-19 in Brazil.

Spread in the United States

The Gamma variant was initially found in the United States in January 2021 in Minnesota.

As of June 15, 2021, The Gamma variant was responsible for more than 8% of new COVID-19 cases in the United States. The Gamma variant has been found in at least 31 states.

Why Do Viruses Mutate?

It is common for all viruses to mutate. When a virus enters the body, it begins to make copies of itself.

Sometimes during this process, mistakes (mutations) are made in the copies, which can make it easier for the virus to invade the cell. When this same mutation continues to further copy itself, a variant of the virus forms.

Is Gamma More Contagious?

The Gamma variant is thought to be more contagious than the original COVID-19 virus based on data from Brazil, but details on the increased risk of transmission have not been reported.

The infectiousness of a virus is measured by a reproduction number—called R0—which measures the number of people an infected person will give the virus to. For example, if the R0 is 1, an infected person is likely to give it to one other person, and an R0 of 5 means an infected person is going to transmit it to five other people. We do not yet know the R0 for the P.1 variant.  

Preventing Transmission

Precautions to prevent the transmission of the Gamma variant are the same as for the original COVID-19 virus and should continue to be followed. Precautions if you're unvaccinated include:

  • Stay 6 feet apart from others who don’t live in your household
  • Wear a mask that covers your mouth and nose
  • Practice good hand hygiene by washing hands often or using hand sanitizer 

If you are fully vaccinated, the CDC has released new guidelines that say you can go without a mask and physical distancing in places where it isn't required by federal, state, or local regulations. Continue regular hand washing.

Risk of Reinfection

It is possible that the Gamma variant can cause reinfection.

Data from Brazil confirmed that it’s possible to be infected with the original strain of COVID-19 and then become reinfected with the Gamma variant. However, further studies are needed to continue to investigate and help determine the risk of reinfection.

Is Gamma More Severe?

Data on the severity of COVID-19 infection from the Gamma variant is limited. However, what is currently available in a study from Brazil does not suggest an increase in disease severity from the P.1 strain.

Recent studies did uncover that specific monoclonal antibody treatments may be less effective for treating cases of COVID-19 caused by the Gamma variant.

Will Vaccines Work Against Gamma?

The World Health Organization (WHO) has reported that the Gamma variant may cause a mild decrease in the effectiveness of vaccines, while some vaccines not in use in the United States are showing effectiveness against this strain. Studies are still ongoing, with more data to come.

Are Kids More at Risk for Gamma?

Currently, there is little data available about the risk of Gamma in children. However, there is no current evidence suggesting this virus causes an increased risk of infection or more severe disease in children.

A Word From Verywell

Experts are worried about the spread of the P.1 variant of COVID-19 around the world and in the United States.

Following precautions as outlined by the CDC and getting a vaccine when it is available to you, as long as it safe for you to do so, is important to help decrease the spread of this and other variants of COVID-19.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Science brief: emerging SARS-CoV-2 variants.

  2. World Health Organization. Weekly epidemiological update on COVID-19—15 June 2021.

  3. Centers for Disease Control and Prevention. First identified cases of SARS-CoV-2 variant P.1 in the United States - Minnesota, January 2021.

  4. Centers for Disease Control and Prevention. COVID-19 tracker.

  5. Cleveland Clinic. What does it mean that the coronavirus is mutating?

  6. Centers for Disease Control and Prevention. SARS-COV-2 variant classifications and definitions.

  7. Centers for Disease Control and Prevention. How to protect yourself & others.

  8. Centers for Disease Control and Prevention. When you’ve been fully vaccinated.

  9. Sabino EC, Buss LF, Carvalho MPS, et al. Resurgence of COVID-19 in Manaus, Brazil, despite high seroprevalenceLancet. 2021;397(10273):452-455. doi:10.1016/S0140-6736(21)00183-5

  10. Faria NR, Mellan TA, Whittaker C, et al. Genomics and epidemiology of a novel SARS-CoV-2 lineage in Manaus, BrazilmedRxiv. Published online March 3, 2021:2021.02.26.21252554. doi:10.1101/2021.02.26.21252554

  11. World Health Organization. Weekly epidemiological update on COVID-19 - 13 April 2021.

By Julie Scott, MSN, ANP-BC, AOCNP
Julie is an Adult Nurse Practitioner with oncology certification and a healthcare freelance writer with an interest in educating patients and the healthcare community.