Do COVID-19 Vaccines Protect Against the Delta Strain?

Medically Reviewed on 1/5/2022
delta variant symptoms if vaccinated
Research suggests that a full course of COVID-19 vaccines could protect you from early mutants such as the Delta strain.

Your immune system is strong and built to fight any organism that invades your body. Vaccines play a major role in the activation of the immune system and the production of antibodies by the immune system even before you get infected by any virus.

Research suggests that a full course of COVID-19 vaccines could protect you from early mutants such as the Delta strain (B.1.617.2).

  • Vaccines approved in the United States, such as the Pfizer/BioNTech jab, are effective against the Delta variant.
  • However, the most recent data stated that one dose of the COVID-19 vaccine may not be highly effective against the Delta variant.

The vaccine’s effectiveness in preventing symptomatic cases of the Delta variant is:

  • 35 percent after one dose.
  • 79 percent after two doses.
  • 80 percent (single dose) and 96 percent (two shots) for people who are hospitalized.

Studies report that a strong vaccine effect against the Delta variant does not appear until one month after the first dose.

The World Health Organization recently expressed concern that the Delta variant of COVID-19, which was discovered in India, is reducing the efficacy of the world's existing COVID-19 vaccines.

  • Most studies on COVID-19 reported that a person is more likely to end up in the hospital if they are unvaccinated and become infected with the Delta variant.
  • Researchers pointed out that single-dose recipients provided a preview of what happens to people who live on the belief of solid immunity.
  • If a single-dose recipient has become infected and recovered, their natural defenses may no longer be effective against the Delta variant. Full vaccination is required to maintain the defenses against all COVID-19-causing viruses, especially the Delta variant.
  • Vaccines are still expected to prevent serious illness caused by the Delta variant among people with healthy immune systems. Senior citizens and people with weakened immunity due to preexisting conditions may be harmed.
  • The World Health Organization reports that deaths among older adults who are fully vaccinated are increasing after being infected with the Delta variant.

The Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention recommended booster doses after evidence of a decline in vaccine effectiveness.

What is the Delta variant?

The Delta variant (B.1.617.2) is a highly contagious strain of coronavirus (SARS-CoV-2) that is responsible for COVID-19 infection. It is now emerging as the dominant strain in the United States. The Centers for Disease Control and Prevention reports that the Delta variant may account for more than 80 percent of COVID-19 cases.

  • The Delta strain emerged due to a change in the spike protein, and it has a high rate of transmission.
  • The Delta variant's high infectivity has raised concerns about the possibility of speeding up the pandemic.
  • According to some reports, the Delta strain may cause different symptoms than other variants.

The most common symptoms of the Delta strain include:

Less common symptoms include:

According to the World Health Organization, the infectious Delta variant of coronavirus has spread worldwide and is now the dominant strain. Research states that it can replicate faster, spread more easily and bind to lung cell receptors more strongly.

What should I do to stay safe against the Delta variant?

Vaccination remains the most effective means of protection and prevention against the Delta variant.

Advantages of being fully immunized include:

  • Protects you from the virus
  • Lessens the severity of the disease if infected
  • Protects people who are not yet eligible to get vaccinated (children younger than 12 years)
  • Protects those who may not be able to mount a robust immune response to vaccines (immunocompromised people)
  • Prevents the virus from replicating and potentially mutating, leading to more variants

Other common protocols include:

  • Ensure ventilation, distancing, and masking.
  • If cases are surging in your region, pay attention to the recommendations of local authorities.
  • If concerning cases increase, especially in regions where vaccination is low, continue to use masks while being indoors even if you are vaccinated.

There is still much to learn about the Delta variant such as whether it causes more severe disease in non-immunized individuals such as young, healthy people. At present, data are mixed.

Although it is uncommon, researchers are investigating how frequently breakthrough infections occur in fully vaccinated people and how fully vaccinated people can spread COVID-19 to others.

Booster vaccines are studied to see if they have to be modified in the future due to new variants, waning immunity, or both and whether certain individuals (such as the elderly or those with compromised immunity) will develop waning immunity faster than others.

Health Solutions From Our Sponsors

Medically Reviewed on 1/5/2022
References
Image Source: iStock Images

COVID Variants and the Vaccine: https://www.umms.org/coronavirus/covid-vaccine/facts/strain

Effectiveness of Covid-19 Vaccines against the B.1.617.2 (Delta) Variant: https://www.nejm.org/doi/full/10.1056/nejmoa2108891

COVID-19 vaccines protect against severe illness during Delta: https://www.cidrap.umn.edu/news-perspective/2021/09/covid-19-vaccines-protect-against-severe-illness-during-delta