Here’s How Well COVID-19 Vaccines Work Against the Delta Variant

• COVID-19 cases are rising in the United States, and the delta variant has been identified in all 50 states.
• The delta variant is now responsible for more than 58 percent of new coronavirus infections in the United States, and there’s been an increase in hospitalizations.
• Of people hospitalized, a majority are either unvaccinated or partially vaccinated.
• Even though vaccines offer different ranges of protection, experts say getting fully vaccinated is crucial.

The United States is now dealing with the delta variant of the coronavirus, a highly contagious variant that was first identified in India in December.

As with previous variants, the delta variant has spread to many countries across the world, including, most notably, the United Kingdom, where it’s now responsible for around 99 percent of new cases.

The United States first announced that it had diagnosed a case with the delta variant in March this year. It’s now the dominating variant nationwide, making up more than half of all new infections in the country.

Confirmed infections with the delta variant have also been doubling since June. The average is more than 24,000 a day, according to data from the Centers for Disease Control and Prevention (CDC).

This rise has been attributed, in part, to the delta variant being an estimated 60 percent more transmissible than the alpha variant, according to recent research.

Additionally, areas with low vaccination rates are more likely to see a surge in infections.

Low vaccine uptake driving up infections

“The unvaccinated population is at high risk for infection. If this variant continues to move quickly, especially in areas of low vaccination rates, the U.S. could see a surge in SARS-CoV-2 infection,” said Dr. Miriam Smith, chief of infectious disease at Long Island Jewish Forest Hills Teaching Hospital in Queens, New York City.

CDC Director Dr. Rochelle Walensky issued a warning on this potential surge earlier this month.

In a press briefing, she said preliminary data suggested that 99.5 percent of the people who died from COVID-19 since January were unvaccinated.

“We know that the delta variant… is currently surging in pockets of the country with low vaccination rates,” she said.

In Missouri, which has a vaccination rate of 40.26 percent, confirmed coronavirus infections have almost doubled in the past 2 weeks.

In contrast, Vermont reported only 32 cases on July 12 and currently has one of the highest vaccination rates in the country at 67.70 percent.

This echoes findings from a U.K. study that found the delta variant twice as likely to lead to hospitalization, and both the AstraZeneca-Oxford and Pfizer-BioNTech COVID-19 vaccines being effective in reducing this risk.

“We also know that our authorized vaccines prevent severe disease, hospitalization, and death from the delta variant,” Walensky said.

Dr. Theodore Strange, the interim chair of medicine at Staten Island University Hospital in New York, said the data supports this.

“The safety and efficacy of the current vaccines are very clear. These three vaccines do work to prevent disease and the spread of disease, and they are as safe as any other vaccines that have been in use. Although some side effects have been reported, these issues are rare and treatable,” he told Healthline.