The delta variant is beginning to surge across the United States as it currently makes up 83% of new infections and it will steadily get worse through the summer and fall before a projected peak in October, according to new research.

The COVID-19 Scenario Modeling Hub and the Centers for Disease Control and Prevention released the new data Wednesday detailing the grim forecast.

The projections from the group show four different scenarios that can play out based on what percentage of the population gets vaccinated and how quickly Delta could spread. Current CDC data shows that 68.7% of adults in the United States have received at least one shot from a COVID-19 vaccine.

The scenario the research found to be most likely would see the Delta variant reaching a peak in the U.S. in October, with 60,000 daily cases and 850 daily deaths. A worst-case scenario is far grimmer, with 240,000 new daily cases and 4,000 new daily deaths. Both could occur if only 70% of the U.S. was vaccinated.

Different variables could change these results, mainly if more people did get vaccinated.

“If we get enough people vaccinated we can stop the delta variant in its tracks,” Justin Lessler, an epidemiologist at the University of North Carolina, told NPR.

The variant, which is more contagious than previous forms of the virus, is putting a quick dampening on efforts for the U.S. to move past the Pandemic and return to normal life, with employers once again considering delays in bringing employees back to the office and schools once again potentially considering virtual learning.

The biggest risk still remains to communities with low vaccination rates, as 99% of hospitalizations in the U.S. for COVID-19 are now among unvaccinated people.

“I strongly suspect that delta is highly prone to super spreading, if I am right it might go off like a bomb in unvaccinated communities,” said William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health.

States with the lowest vaccination rates, which according to The New York Times include Mississippi, Louisiana, Wyoming and Alabama, could be at the highest risk as a result.