(CNN) Dr. Thomas Weiser will never forget the look in the eyes of the first gunshot victim he ever treated. The patient was a teenage boy with a wound to the chest.

"He was a gang member, and there were social circumstances that certainly played a role in his ending up in the emergency room," said Weiser, who at the time was a medical student at the University of New Mexico. He now is a trauma surgeon at Stanford University Medical Center.

"It was, as a medical student, incredibly powerful," Weiser said of treating the boy. "He had a very devastating injury but actually survived and walked out of the hospital, which is phenomenal."

The majority of gun deaths are suicides , Weiser said, but there's not much data on the gun-related injuries that send patients such as that teenager to the hospital. In an average week, about 1,565 patients across the country are treated in an emergency department for a firearm-related injury.

A new study sheds light on just how much gun-related injuries cost the United States, from the health care system to victims' families.

The study, published in the American Journal of Public Health on Tuesday, showed that between 2006 and 2014, the costs and financial burden of firearm injuries reached a total of $6.61 billion -- and that was just for initial hospitalizations.

"When we began our study into the costs of treatments for firearm injuries, we knew in advance that costs would be high. I was actually surprised that they were not higher," said Weiser, senior author of the study and an associate professor of surgery at Stanford University.

"The costs of hospitalizations for firearm injuries increased slightly from 2006 to 2014, but not dramatically. The real story is that we spend over $700 million a year paying for these hospitalizations," he said. "That does not include follow-up costs, costs of readmissions or disability or home medications or loss of work."

In other words, more research is needed to determine the true long-term cost of gun violence, but for the price tag of initial hospitalizations, the study offers an idea.

How much do gunshot wounds cost us?

The study included nationwide data on hospital patients with firearm-related injuries between 2006 and 2014. The data came from the Healthcare Cost and Utilization Project , which includes the largest collection of longitudinal hospital care data in the US.

The researchers analyzed the data with a close eye on hospital costs for the patient's initial injury, which does not include costs of readmission or rehabilitation.

"However, lots of people suffering firearm injuries never make it to the hospital, so they do not show up in hospital cost data sets," Weiser said. "We are really looking here at patients that survived long enough to be admitted, so people who died or were never admitted to the hospital are not captured by this database."

The researchers found that a total of 267,265 patients were admitted for firearm-related injuries from 2006 through 2014, and the cost of initial hospitalizations for their injuries averaged $734.6 million per year.

Medicaid paid the largest proportion, about one-third, of those costs, and self-paying patients paid one-quarter while Medicare, private insurance and alternative forms of insurance, such as charity care, covered the rest.

"I think it is important to put dollar costs to the medical care needed for patients injured by firearms," Weiser said. "Once we start to recognize the actual costs in dollars, we might stimulate a more frank discussion around how to make policies that can reduce injuries and deaths. The technology exists to make guns safer, but it has to be supported by policies that promote it."

The researchers also found that 43% of all initial hospital admissions for firearm-related injuries were in the South. The West and Midwest each had 20% of the injuries, and the Northeast had 16%.

"Gun injuries now still do not come close to the high of gun violence that was seen in the late 1980s and early 1990s. So overall, we are in a better place with respect to our history, but when we look at any other comparable country, we are a huge outlier," Weiser said. "No other developed country that is not at war experiences the rate or volume of gun deaths like we do."

'It meets the definition of a disease'

The gun-related homicide rate in the United States is about 25 times higher than that in other high-income countries around the world, said Dr. Jonathan Fielding, professor of health policy and management, and pediatrics at the University of California, Los Angeles' Fielding School of Public Health, and the David Geffen School of Medicine at UCLA.

Although Fielding was not involved in the new study, he said, "I think the study is well-done, and it shows that the government does have an enormous percentage of firearm costs for initial hospitalization."

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Fielding added that he thinks the public health community and gun owners in America can find common ground when it comes to preventing firearm-related injuries and deaths.

"I don't think anybody wants homicides or suicides with guns, so you know, making sure that there are appropriate background checks is important. I know that's the subject of some controversy currently on the national level, but I think it's important," he said.

"If you look at Virginia Tech or Sandy Hook or the Emanuel African Methodist Episcopal Church in Charleston, they've been linked back to the shooters' mental health. I think there's an agreement that mental health programs or referral to those programs will be a way to reduce gun violence," he said. "I also think that we have to be very careful about who has access to guns, so making sure that they are stored in places that are not accessible to children or easy to steal. I would hope there would be agreement about that."

Many experts have also called for more data on rates of firearm-related injuries and deaths.

More research is needed to determine long-term costs and financial burdens of firearm injuries, as well as to identify ways to prevent and better treat injuries, said Dr. Stephen Hargarten, a gun violence researcher, professor and chairman of emergency medicine at the Medical College of Wisconsin. He was not involved in the new study.

Hargarten said that examining the costs and financial burdens of firearm injuries is no different than quantifying the burdens of other illnesses or injuries that the medical community often treats.

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"It meets the definition of a disease. A disease is caused by an agent. In the case of the flu, it's caused by a virus," Hargarten said. For gun violence, the agent of the disease is the kinetic energy of a bullet that causes damage to tissue and organs, he added.

"The bullet enters the body, and the energy, as it dissipates, tissues stretch and lacerate, bones fracture. The bullet and its kinetic energy causes acute injury," Hargarten said.

"We advocate for research funding support so we can seek better ways to prevent these injuries and to improve the treatment of these injuries that impact long-term disabilities," he said. "We're always wanting to see that happen just like we would do for any other disease burden that frequents our emergency departments."