Health Headlines - August 22

New Chewing Gum Fights Cavities

Chewing gum that contains "friendly" lactobacillus bacteria that help prevent tooth decay has been developed by the German chemical company BASF and could be introduced to the market in 2007, The Herald in the U.K. reported.

The strain of lactobacillus in the gum fights streptococcus mutans bacteria that cause tooth decay by sticking the surface of teeth and producing a powerful acid that breaks down enamel.

The lactobacillus anti-caries in the gum forces streptococcus mutans to clump together. That prevents the bacteria from sticking to teeth and makes it easy to rinse them out of the mouth, The Herald reported.

Tests showed that the chewing gum could reduce the amount of harmful bacteria in the mouth by 50 times, according to an article in Chemistry & Industry magazine.

It's believed that BASF is also developing other related bacteria products, including toothpaste, mouthwashes, and deodorant, The Herald reported.

British Man Killed by Rabbit Flu

A 29-year-old Suffolk farmer is believed to be Britain's first victim of rabbit flu and his mother is warning others about the potentially deadly disease, BBC News reported.

"People should just be aware that there is this dreadful thing around and potentially it's lethal," warned Joan Freeman.

The victim, John Freeman, became infected in early August after he picked up a rabbit on his farm. He became ill and died four days later.

Health officials said Freeman died from septicemia after becoming infected with Pasteurella multocida bacteria, which causes pasteurellosis (rabbit flu).

This bacteria is common among many domestic animals, including dogs and cats, a Health Protection Agency spokesman told BBC News. But he said he wasn't aware of any other cases of fatal rabbit-to-human transmission of the bacteria.

Each year a few people are infected with the bacteria, usually from dogs or cats, and deaths are rare, the spokesman said.

HIV Flicks Switch to Disarm Immune Cells

When the body's immune system sends T cells to attack HIV -- the virus that causes AIDS -- the virus disarms the T cells by flicking a molecular switch on the cells, according to a U.S. study in the journal Nature.

In laboratory tests, the researchers found a way to jam this switch and restore T cell function. The findings may lead to more effective treatments for HIV/AIDS, BBC News reported.

There are already drugs available that can do this, but they may not be specific enough and could cause serious side effects, said the study authors. More research needs to be done, they said.

"One has to proceed with real caution because if you turn back on an immune system regulatory switch that the body has decided to turn off, you could trigger serious immunological problems," lead scientist Bruce Walker, a Howard Hughes Medical Institute researcher at Massachusetts General Hospital, told BBC News.

For this study, the scientists analyzed blood samples from 71 people who'd recently been infected with HIV but had not yet started antiretroviral therapy. The researchers also studied blood samples taken from four HIV-positive patients before and after they started treatment.

Discovery May Lead to Lyme Disease Vaccine

A newly-identified immune system trigger for fighting Lyme disease could help in the development of a new vaccine to prevent the tick-borne disorder, say researchers at California's La Jolla Institute for Allergy and Immunology.

The international study found that Borrelia burgdorferi, the bacteria that causes Lyme disease, contains a glycolipid that triggers an immune response from the body's natural killer T cells.

This is one of the few glycolipids that naturally induces an immune response from T cells, the researchers said. Their findings were published Sunday in the online edition of the journal Nature Immunology.

Lyme disease, which is transmitted to people through the bite of an infected tick, can cause fever, headache, fatigue, and skin rashes. Left untreated, the infection can spread to the joints, heart, and nervous system, causing serious health problems.

Jury Selection Slated in First Prempro Trial

Jury selection is to begin Monday in the first trial of 4,500 lawsuits filed in the United States alleging that the hormone replacement therapy (HRT) drug Prempro causes breast cancer and other health problems.

This federal court case against drug maker Wyeth involves Linda Reeves, who says she developed breast cancer after taking Prempro for eight years, the Associated Press reported.

According to Reeves' lawyers, there's evidence that Wyeth willfully ignored known dangers of the drug, including an increased risk for breast cancer. The drugmaker says it didn't ignore the risks and that Prempro's label warned about the risk of breast cancer.

In 2002, a Women's Health Initiative study concluded that women who took Prempro -- a widely prescribed combination of estrogen-progestin -- had an increased risk of breast cancer, coronary heart disease, and stroke.

Indonesia Downplays Likelihood of Bird Flu Cluster

Even though at least three Indonesians in the same area of West Java have been infected with the H5N1 bird flu virus, officials are downplaying the likelihood of a bird flu cluster case, Agence France Presse reported.

All three confirmed cases were from Cikelet, a group of villages in the Garut district. Two of the three patients died. While three other people from the area also died after exhibiting symptoms of bird flu, they were buried before they could be tested for H5N1.

A cluster case refers to human-to-human transmission of the bird flu virus, rather than infection through contact with sick birds. It's believed that cluster cases increase the risk of the H5N1 virus mutating into a form that's easily spread among people.

Despite the multiple cases in this one area, Indonesian officials say they don't yet have enough evidence to label it a cluster case.

"We cannot yet classify it as a cluster because the distance between one patient with the others was too far for them to have had contact," I Nyoman Kandun, director of the health ministry's communicable disease control center, told AFP.

Indonesia has reported 46 bird flu deaths, the most of any country in the world. Health experts have criticized Indonesia for failing to take prompt action to curb the spread of the bird flu virus by conducting mass slaughters of poultry.