Broadcast: December 2, 2003
This is Science in the News, from VOA Special English. I'm Bob Doughty.
And I'm Sarah Long. This week -- advice about food safety ... and, a report on climate change and the quality of wine.
Also -- a study of the health value of drinking hot cocoa ... and, experts look for ways to get people to take their medicine.
More than six-hundred people in the eastern United States recently became sick with the liver disease hepatitis A. They all ate at the same restaurant in Pennsylvania. They all got sick from uncooked green onions imported from Mexico.
The Pennsylvania health department said last week that three people had died. More than nine-thousand people received injections of immunoglobulin as a preventive measure.
The virus that causes hepatitis A is spread through infected body waste. Most people suffer only a few effects such as high body temperature and yellowish colored skin. These generally go away after a few weeks. People with weak defense systems, though, can die.
Experts say people should cook all foods well to prevent hepatitis and other infections. People should also wash their hands before they touch food. This includes farm workers.
Keep food preparation surfaces clean. Wash fruits and vegetables. But keep in mind that diseases like hepatitis A can also spread if food is kept in ice made from water that contains the organism.
Another common cause of food-related sickness is the bacteria E. coli. It also is passed from one person to another through infected body waste.
Most people infected by E. coli suffer stomach pains. They also may have diarrhea. Young children and older people can die from E. coli infections. Experts say to drink only milk that has been heated through pasteurization to kill bacteria. And cook all meats long enough and at a high enough temperature to kill harmful bacteria.
There are different temperatures for different foods. Ground beef, for example, should be cooked to at least seventy-one degrees Celsius. Turkey and chicken should reach eighty-two degrees Celsius.
Listeria is another dangerous bacteria spread in food. Listeria is found naturally in soil and water. Vegetables can become contaminated from the soil or from animal waste used as fertilizer. Unpasteurized milk and cheese may also contain the bacteria.
People infected by listeria develop a high body temperature, muscle aches and diarrhea. Again, food safety experts say people should cook foods to avoid infection. And they should wash their hands and cooking tools after they touch uncooked foods. Also, make sure the liquid from uncooked meat does not touch other foods.
Other dangerous bacteria include salmonella and campylobacter. These are spread by foods that are not cooked enough. Victims have a high fever, diarrhea and stomach pain. Salmonella infection can kill if it spreads through the bloodstream untreated.
The United States government has a Web site with information about food safety. The address is w-w-w dot foodsafety -- all one word -- dot g-o-v. Again, w-w-w dot foodsafety dot g-o-v.
Scientists say they have shown a link between climate change and the quality of wine. They found that wine quality improved as temperatures rose during the past fifty years. But they say some wine producing areas could have problems if temperatures continue to rise.
Gregory Jones of Southern Oregon University presented the findings at a meeting of the Geological Society of America. The yearly meeting took place in Seattle, Washington, in the Pacific Northwest. The publication Climatic Change is planning to report the findings.
Professor Jones worked on the study with researchers from Utah State University and the University of Colorado. They studied twenty-seven areas where farmers grow the grapes used to produce top wines.
The researchers examined temperature records from nineteen-fifty to the present. They found that average temperatures rose by about one-point-three degrees Celsius. The researchers also used a system developed by Sotheby’s auction house to rate wine quality. They found that wine quality has improved during the past half-century. They said the effects were strongest in areas with cool climates.
Next, the researchers estimated how climate changes might influence the same twenty-seven areas in the future. They used a computer program, a long-term climate model, to complete this part of the study. They expect temperatures in the wine producing areas to rise another two degrees during the next fifty years.
If the weather is too hot or too cold, then grapes do not reach their full flavor. So the researchers say cool areas should continue to see improvements in wine quality. But they say higher temperatures could hurt wine production in areas that are already warm.
What do winemakers think of these findings? One expert in California told a reporter from Wine Spectator that this is all just theory. Another says progress in grape growing and winemaking has, and will continue to have, the greatest effect on the increase in wine quality.
In cold weather, many people like to drink hot cocoa -- chocolate mixed with water or milk. Now a study finds that hot cocoa contains more antioxidants than wine or tea. Antioxidants have been shown to help prevent cancer, heart disease and other conditions.
The body produces compounds that cause oxidation. Atoms and molecules called free radicals are involved. Oxidation damages cells and tissue. Experts say this damage causes many of the health problems common in older people. Antioxidants reduce or prevent oxidation.
In recent years, other studies have shown the health value of drinking red wine and tea. Both are known to be high in antioxidants.
Chang Yong Lee of Cornell University in the United States led the new study. He is a professor of food chemistry. Professor Lee and his team compared the antioxidant levels of hot cocoa to those of tea and red wine.
They tested one serving of hot water containing two tablespoons of pure cocoa powder. They also tested a cup of green tea, a cup of black tea and a glass of California red wine.
Cocoa is a fine powder made from the seeds of the cacao tree. Most of the world’s cacao beans come from the west coast of Africa.
The Cornell team found that, per serving, cocoa had the highest antioxidant levels. It had almost two times more than the red wine. It had two to three times more than the green tea. And it had four to five times more than the black tea.
The findings appear in the Journal of Agricultural and Food Chemistry, published by the American Chemical Society. A South Korean development agency provided part of the money for the study.
Professor Lee says we know that antioxidants in foods are important for good health. But there's a problem. He says nobody knows exactly how much we need each day.
The World Health Organization says medical progress against disease will have no effect unless people take their medicine.
This is common sense. But the W-H-O says only about half of people in developed countries continue their treatments for serious medical conditions. Such adherence rates are even lower in developing countries.
To improve the situation, the W-H-O is leading an international effort, the Adherence to Long-Term Therapies project.
The W-H-O says health care providers need training to judge a patient's ability to understand and continue with treatments. Providers need to give advice about how people can follow their treatments. And they need to examine the patient's progress at every chance.
The report says patients need to be supported, not blamed. It says another way to improve adherence is to get the support of the patient's family and community. In fact, the W-H-O says improving adherence to existing treatments may have better results than providing new ones.
SCIENCE IN THE NEWS was written by George Grow and Cynthia Kirk, who was also our producer. This is Bob Doughty.
And this is Sarah Long. Join us again next week for more news about science, in Special English, on the Voice of America.