By Maria Medina

SAN JOSE (KPIX 5) – The battle against COVID-19 is intensifying once again as the Delta variant causes surges across the country among the unvaccinated, and more breakthrough cases are reported among those who have received their shots.

Despite the resurgence of the virus, particularly among unvaccinated populations, doctors and experts continue to reassure the public the risk of infection is much lower for those who are vaccinated.

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“Ninety-nine percent of all the cases occurring in the U.S. right now, certainly hospitalizations and deaths, are among unvaccinated people,” said Stanford School of Medicine Dr. Bonnie Maldonado.

On Wednesday, the California Department of Public Health released new numbers that show the state’s seven-day positivity rate at 3%; much higher than this time last month when it stood at 0.8%.

New cases in almost every state are up at least by 10%.

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“I was like, ‘What are the chances?’ And I got tested just in case,” said Ammon Van Orden.

The California resident is among the country’s rare breakthrough cases. Van Orden said he was vaccinated in January, and came down with cold-like symptoms this week. He tested positive for COVID-19.

“It just sucks when you’re like, ‘Well, I thought I was safe,’ and not so much,” Van Orden said.

From January to April of this year, the Centers for Disease Control and Prevention reported 10,262 in 46 states. The agency stopped tracking breakthrough cases after April. However, more and more vaccinated people have posted on social media in the last few weeks about becoming infected with the virus.

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There is a push, especially among young adults, to get vaccinated. Actress, singer and songwriter Olivia Rodrigo paid a visit to the White House Wednesday to encourage youth vaccinations.

A newly released University of California San Francisco study, which surveyed adults 18 to 25 in March, found that one in four said they would probably not or definitely not get the vaccine despite the demographic found to be more likely to spread the virus than any other age group.

“Young adults are a really important population to getting vaccinated,” said UCSF Asst. Prof. of Pediatrics Jason Nagata. “I think that a lot of the mental illness that we’ve seen at UCSF, we’ve seen a doubling of hospitalizations for suicides and eating disorders, all of that is I think probably directly related to social isolation. So I think that getting the vaccine will allow young people to socialize again more normally.”

Van Orden said he believes the vaccine helped stave off severe disease, and caused him more mild, cold-like symptoms.

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The CDC has made it clear breakthrough cases were expected as no vaccine is 100% effective.

But Van Orden is now missing his family reunion this and next week, and his two kids must also quarantine for two weeks in case they become infected with COVID-19.

He said he’s glad, however, he caught it before he could spread the virus to his relatives.

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“We had pushed this off, this family reunion for a year because of COVID last year, and I had to just tell them all I couldn’t do it this year, which is a real bummer,” said Van Orden.