The highly contagious Delta variant of the coronavirus is now the third-most common in California, posing a danger to people who have not received a dose of their COVID vaccines.

As of now, the Delta variant accounts for 14.5 percent of California COVID cases, which is a 4.7 percent increase in May when it was the fourth-most identified COVID strain in California, Los Angeles Times reported.

Health experts noted that the Delta variant shows a greater chance of infection for unvaccinated people if exposed to this virus strain. Vaccinated people are well protected against infection and illness from the Delta variant.

The full vaccine of Pfizer-BioNTech offers 88 percent effective protection against symptomatic disease caused by the variant. Pfizer-BioNTech is also 96 percent protective against hospitalization.

Los Angeles County Public Health Director Barbara Ferrer said that fully vaccinated people infected with the Delta variant experienced relatively mild illness. Ferrer further noted that the new virus strain is a pandemic of unvaccinated people.

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The Delta Variant

The Delta variant has been first detected in India and has been identified in at least 92 countries. It is also considered the fittest variant yet of the coronavirus that caused COVID-19 with its enhanced ability to prey on areas with low vaccination rates, The Guardian reported.

According to research conducted in the United Kingdom, the variant accounts for 99 percent of new COVID cases. It also shows it is about 60 percent more transmissible than the Alpha variant, which was the first dominating strain.

Dr. Stephen Griffin, a virologist and associate professor at the University of Leeds school of medicine, said people need a much higher coverage to protect against a more transmissible variant.

Scientists have yet to explain why the Delta strain has a significant transmission advantage. But Professor Catherine Noakes, a UK's Scientific Advisory Group member for Emergencies, cited three possible reasons.

The cited reasons were that the people it infects have a higher viral load, which would allow them to emit more particles.

The second one was that people need to be exposed to less of the virus to become infected. Lastly, a relatively short exposure time to an infected person is enough to spread the disease.

Meanwhile, the World Health Organization (WHO) urged fully vaccinated people to continue wearing masks, maintain social distancing, and practice other safety measures.

The COVID Strain in California

The Los Angeles County's public health director urged the public to practice safety measures when attending events indoors or working.

Ferrer said that sensible public health precautions are recommended at all worksites and mega-events, NBC Los Angeles reported. 

State regulations for work sites mandate unvaccinated workers to wear masks indoors, while employers are required to offer them N95-grade face masks. Employees are also required to keep a log of workers' vaccination status.

Ferrer noted the lagging rates among Latino and Black communities when compared to white and Asian counterparts. The Latino and Black communities still have the highest current rate of infections, hospitalizations, and deaths.

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