How COVID-19 Testing Helps Against the Rapid Spread of the Delta Variant

How COVID-19 Testing Helps Against the Rapid Spread of the Delta Variant

The Delta variant is considered to be more infectious and is reported to spread more easily than early forms of COVID-19. It is also currently the predominant variant of the virus around the world, including the United States and India.

This newer strain of COVID-19 was first identified in India in December and began spreading more rapidly even outside the national borders starting from the middle of June. In the U.S., for example, the Delta variant accounts for more than 80% of new cases, according to statements from the CDC.

COVID-19 testing is essential to detect the presence of the viral genetic material or COVID-19 antibodies. While there exist several different types of testing options, the demand for at-home COVID-19 tests has seen a sharp rise in recent weeks as the Delta variant spreads across the U.S.

In this article, we will review how COVID-19 testing is supporting the research against the Delta variant and the spreading of the virus.

The Delta Variant Is More Transmissible

According to the CDC, the Delta variant of COVID-19 is more contagious than any other virus strain. It is also more transmissible than other viruses in the coronavirus family, including MERS and SARS.

The UC Davis Health official website reported that, as of July 22, nearly 80% of its patients who tested positive for COVID-19 had the Delta variant. The symptoms of this new strain appear to be the same as the original version of COVID-19. However, the Delta variant is highly contagious,  seemingly more than the other variants. Spreading at a higher rate, it is making the pandemic control even harder.

Research and news around the world confirm the higher transmission rates of the Delta variant.

The Unvaccinated Are at Greater Risk for Infection

A recent survey from the Kaiser Family Foundation reports that just over half of Americans who remain unvaccinated against COVID-19 still believe the vaccine is more dangerous than the virus itself. About 14% of the 1500 U.S. adults surveyed by this health-focused nonprofit group reported that they will “definitely not” get vaccinated. The proportion remained the same as in December 2020.

However, despite COVID-19 vaccine hesitancy, governments and researchers worldwide strongly emphasize the importance of vaccination. Unvaccinated or partially vaccinated individuals are more likely to be infected with COVID-19 and to spread the virus for a longer time than vaccinated people.

Furthermore, data from two different studies suggests that the Delta variant might cause more severe illness than previous variants in unvaccinated people. A study published in the International Journal of Pharmacology and Clinical Research, stated that the new strain can quickly enter and infect an unvaccinated person’s body.

COVID-19 Vaccines Effectiveness and Protection

Researchers at the University of Oxford published a preprint on August 19th where the results suggest that the Pfizer–BioNTech and Oxford–AstraZeneca COVID-19 vaccines are effective against the highly infectious Delta variant. In particular, their effectiveness reaches higher ranges (92% for Pfizer and 69% for AstraZeneca) only 14 days after the second dose. [1]Other research suggests similar findings, including a recent study from the New England Journal of Medicine. In other words, COVID-19 vaccines are critical to protect an individual from COVID-19, while also avoiding the risk of passing the infection on to others.

Can COVID-19 Tests (PCR/Antigen Tests) Detect the Delta Variant?

A viral test (PCR or Antigen test) checks specimens from a person’s nose or mouth to determine whether this person is currently infected with the virus that causes COVID-19. Although there is not a specific test for the Delta variant, identifying different variants requires a specific type of test referred as “genomic sequencing”.

Genomic sequencing decodes the virus’s complete set of genes and searches for new mutations, including the Delta variant. Viral tests can detect if a person is positive for COVID-19. However, they can not be used to identify what specific variant this person is infected with.

Due to the high volume of COVID-19 cases, genomic sequencing is not performed on every test. According to the Human and Health Services of Texas, genomic sequencing could be performed on some if a COVID-19 test result is positive.

COVID-19 viral tests are still currently used to diagnose a current infection with COVID-19. In particular, a polymerase chain reaction (PCR) test looks for the presence of viral RNA in a nasopharyngeal swab sample in the lab. The test is positive before antibodies form and/or while the symptoms last. 

An antigen test searches for the antigens, which are protein markers found outside the virus. Various types of sample can be used for antigen test including nasal or throat swab.[2]


Mutations always arise as viruses spread, and the Delta variant is an example. The long-term effects of these constellations of viral mutations for vaccination programs still remain a bit of a mystery. More research is needed to understand the biological basis for the behavior and spread of this new variant.

In addition to vaccinations and preventative measures, widespread COVID-19 testing plays a key role in containing and mitigating the COVID-19 pandemic. Since the beginning of the pandemic, healthcare manufacturers around the world have raced to provide effective solutions for saving lives.

Wondfo Biotech has been at the front line in the fight against COVID-19 and its new variants. This leading POCT manufacturer provides a series of COVID-19 testing solutions that are already employed in 140 countries and regions worldwide.

For example, Wondfo’s Antigen Test Kit is a quick and reliable method for the detection of COVID-19 infection. This advanced kit follows the lateral flow method and provides testing results within 15 minutes.

Visit Wondfo’s official website for more information about their reliable and accurate COVID-19 testing kits.