Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

Hospital Tech in Hepatitis C Outbreak Pleads Guilty

A hospital technician linked to a multistate hepatitis C outbreak pleaded guilty Wednesday to federal drug charges and will be sentenced at a later date.

David Kwiatkowski, 34, worked in 18 hospitals in seven states before being hired at Exeter Hospital in New Hampshire last year. Forty-six people in four states have been diagnosed with the same strain of hepatitis C carried by Kwiatkowski, the Associated Pressreported.

The Michigan native was accused of stealing painkiller syringes from Exeter Hospital and replacing them with saline-filled syringes contaminated with his blood.

Under a plea deal enabling him to avoid charges in other states, Kwiatkowski pleaded guilty to 14 charges of drug theft and tampering. He faces 30 to 40 years in prison, the APreported.


Florida Boy Infected with Brain-Eating Amoeba

A 12-year-old Florida boy has been infected with a rare, brain-eating amoeba found in warm freshwater, the U.S. Centers for Disease Control and Prevention says.

Zachary Reyna's family told TV station WBBHthat he was kneeboarding in a water-filled ditch near his house on Aug. 3 and slept the entire next day. This was unusual, so his family took him to the hospital, where he underwent brain surgery. He is currently in the intensive care unit at the Miami Children's Hospital.

The Naegleria fowleriamoeba enters the body through the nose and travels to the brain. An expert told CNNthat it kills 99 percent of people who get it.

This is the second such infection in the U.S. in less than a month. The other case involved 12-year-old Kali Hardig in Arkansas. She is now in rehab and listed in fair condition.

The same experimental drug used to treat Hardig was released by the CDC to treat Reyna, but it's not clear if the drug has been, or will be, given to him, CNNreported.


FDA Looking at Sleep Drugs' Impact on Driving

The impact that sleep drugs have on people's ability to drive the next morning is a new area of concern for the U.S. Food and Drug Administration.

Recent evidence appears to confirm what many people have long suspected: that the effects of sleep drugs can persist well into the next day. This is something that consumer advocates have warned about for years, The New York Timesreported.

Last month, the FDA rejected an application for a new sleep drug from Merck, in part because tests showed that some people had difficulty driving the day after taking the drug suvorexant.

The FDA says it is taking a closer look at all sleep medicines on the market and will ask manufacturers to conduct more extensive driving tests for all new sleep drugs. The agency also plans to take a closer look at any drug that causes drowsiness, The Timesreported.


NYC Meningitis Outbreak Halted by Vaccination Campaign

An aggressive vaccination campaign appears to have halted a bacterial meningitis outbreak among gay and bisexual men in New York City, according to health officials.

Twenty-two men have been infected and seven of them have died since 2010. The number of infections accelerated last fall and early this year and raised fears of a new AIDS-type epidemic, The New York Timesreported.

City health officials launched a vaccination campaign and at least 16,000 people have been vaccinated. The last case of the highly lethal disease was in mid-February, which is the longest period of time without a new case since January 2012.

"We think that because we've had no cases in six months, we have to conclude that enough of the population has been vaccinated to provide protection at least for now," said Dr. Jay Varma, the city's deputy commissioner of disease control, The Timesreported.

"Whether or not this provides protection for several years is something that we'll have to see," Varma added.


Mouse Study Finds Even Small Amounts of Added Sugar in Diet Harm Health

Eating added sugars, even at levels that are within recommended limits for humans, could be toxic, a new mouse study suggests.

Researchers gave mice an amount of extra sugar in their diet that matched the current recommendation for humans of no more than 25 percent of a person's diet, Fox Newsreported Tuesday. When compared to a control group of mice that were not fed the added sugar, the first group of mice died sooner, produced fewer babies and gained control of less territory during their 32-week life spans.

"The odd things is our mice passed their physicals. They really didn't look any different from control animals," first study author James Ruff, a doctoral graduate from the University of Utah, told Fox News.

In terms of obesity rates or fasting insulin, glucose or triglyceride levels, there were no differences between the two groups of mice, the researchers reported in Nature Communication.

Only cholesterol levels were higher in the sugar-fed mice, and female mice who were fed sugar had more trouble clearing glucose from their bloodstream, Fox Newsreported.

"One common criticism of animals studies is they look at doses irrelevant to the human condition, which makes them more difficult to translate," Ruff said in explaining the amount of sugar they gave to the one group of mice. "We wanted to pick something relevant to human health."

The researchers noted that even though the effect on health was small, most people would be concerned that the added sugars everyone eats every day might be causing harm in the long run.


New Coke Ads Defend Safety of Aspartame

A print ad from Coca-Cola defending the safety of the artificial sweetener aspartame will debut in USA Todayin the Atlanta area Wednesday, followed by the Atlanta Journal Constitutionon Thursday and the Chicago Tribunenext week.

The ad contends that diet drinks can help people manage their weight and emphasizes the scientific evidence showing that aspartame, more commonly known under the NutraSweet brand name, is safe, the Associated Pressreported.

A growing number of consumers are concerned about the safety of aspartame, despite reassurances from organizations such as the U.S. Food and Drug Administration and the American Cancer Society.

"Coke is trying to get out front and proactively defend these diet sweeteners," John Sicher, editor of the industry journal Beverage Digest, told the AP.

The move comes as sales of both regular and diet soft drinks decline in the United States. Last year, sales of Coke fell 1 percent and Diet Coke fell 3 percent. Sales of Pepsi dropped 3.4 percent and Diet Pepsi declined 6.2 percent, according to Beverage Digest.

Both Coke and Pepsi are attempting to develop a drink that uses natural, low-calorie sweeteners, the APreported.