5 southern states have seen vaccine uptake more than triple in the past month. It's not just the Delta variant that's making people clamor for first shots.

• Five states have seen the biggest increase in first-dose uptake since July 6.
• They are Louisiana, Mississippi, Alabama, Arkansas, and Oklahoma.
• Delta fear was a big motivator, but other factors were also at play, experts told Insider.

Vaccinations in the US slowed to their lowest levels in the first week of July. Cases were down and with them, the enthusiasm of the vaccine-hesitant.

But that all changed in early July, as the Delta variant became dominant. Cases rose again, hitting the states with low vaccination rates the hardest.

Vaccine demand rose most prominently in Louisiana, Mississippi, Alabama, Arkansas, and Oklahoma, an Insider analysis found. Here's why, according to experts and state officials.

A 'traumatizing' increase in cases

Per Insider's analysis of Centers for Disease Control and Prevention data, demand for first shots between July 6 and August 19 rose by:

• 400% in Louisiana - where 39% were fully vaccinated as of August 19, per Our World in Data.
• 340% in Mississippi - 36% fully vaccinated.
• 330% in Alabama - 36% fully vaccinated.
• 230% in Arkansas - 39% fully vaccinated.
• 220% in Oklahoma - 42% fully vaccinated.

States with the highest vaccination rates saw rises in first-dose uptake, but they were less pronounced: Uptake in Vermont, which had fully vaccinated 66% of its population on July 6, rose by 58% as of August 19; in Massachusetts, which has fully vaccinated 62% of its population, it rose by 65% in the same time frame.

The rise in cases has been "traumatic," Dr. Dale Bratzler, Chief COVID Officer at Oklahoma University, told Insider.

Vaccines help protect against severe infection, hospitalization, and death from the coronavirus, including with the Delta variant.

"The pleas of sick or sadly, dying, loved ones to get vaccinated do indeed have an impact on immediate family and friends," Maureen Miller, an epidemiologist at Columbia University, told Insider.

More young people dying in this wave is also prompting people to get vaccinated, said Dr. Dawn Marcelle, a regional director for Louisiana's Department of Health, and Dr. Samuel Jones, Director of Health Services at Jackson State University, separately.

Back-to-school season

As schools restart in-person learning, some parents are also rushing to protect their kids.

"People who might not do it for themselves are considering it for the children because children under 12 are not eligible for the vaccine," Marcelle said.

The 2021/2022 academic year has just started, but tens of thousands of children are already quarantining, Forbes reported. The number of children hospitalized with COVID-19 is also at an all-time high.

Col. Rob Ator, Arkansas' vaccine coordinator, told Insider that children aged 12 to 18 made up 23% of doses delivered this past week.

Jones, of Mississippi University, also said his students sought the vaccine as they returned to campus and found activities like athletics requiring vaccination or regular testing to attend. (Hundreds of US colleges have imposed their own vaccine requirements.)

"We had a good bit of resistance in some of our most macho teams," he said. "But they're beginning to break."

And as trust in the vaccine grows, so does peer pressure: "It's becoming a popularity contest," Jones said.

Better outreach

Ator said tailoring vaccine outreach was also helping alleviate people's fears of the shot.

"As a general rule, when you talk about rural America, they don't like people telling them what to do," he said.

"The harder we push, the harder they dig in their heels and come up with their own excuses. So a lot of what we're doing is not pushing, and giving information."

Jones, Ator, and Marcelle also expressed hope that more will be reassured to get the shot when the Food and Drug Administration fully approves COVID-19 vaccines, which only have emergency-use authorization so far.

But while the experts were encouraged by the vaccine uptake, they warned of new cases and hospitalizations in the short term.

The Pfizer and Moderna vaccines "take five to six weeks to kick in," said Miller, the epidemiologist. "That is far too late for the current wave of infections."

"We will continue to see increased hospitalizations and deaths, which were completely preventable."