Broadcast: September 16, 2003
I’m Bob Doughty with Sarah Long, and this is the VOA Special English program, SCIENCE IN THE NEWS.
This week -- reports about tuberculosis ... smoking ... a new birth control pill ... and, from the mouth of a lizard, a possible treatment for diabetes.
Very often, people who have tuberculosis do not take all their medicine. Maybe they get some side effect they do not like. Or they start to feel better. So they do not take their medicine for the full six months.
The result is what doctors call multi-drug resistant T-B. The bacteria that caused the lung disease become stronger. People who develop this form must often spend two years on special drugs that cost a lot more.
Mario Raviglione is director of T-B operations for the World Health Organization. He says countries that do a good job of controlling T-B with regular medicines do not have a big problem with the multi-drug resistant kind. He says Chile and Cuba are examples.
Health experts say countries with the highest rates of multi-drug resistant T-B include Estonia, Yemen, Kyrgyzstan, Latvia, Pakistan and Sudan. Right now the problem is not as great in Africa. But experts worry that it could become much greater because H-I-V is so widespread. H-I-V is the virus that causes AIDS. The virus weakens the body's defenses against disease.
The most successful treatment program for T-B is called DOTS, or Directly Observed Treatment, Short-course. A health care worker watches a patient take every dose of medicine. A six-month supply costs eleven dollars. When DOTS is followed correctly, experts say ninety-five percent of patients are cured. They say this is true even in the poorest countries.
When a person with multi-drug resistant T-B coughs, it spreads the bacteria in the air. Now other people who breath the infected air can get sick.
People infected with H-I-V are much more likely to become sick. Experts say H-I-V is the single biggest reason that a T-B infection becomes active tuberculosis. That is why health care organizations say it is important to fight both T-B and H-I-V together.
It is also important to fight smoking and tuberculosis together. Researchers in India have shown a connection between people who smoke and people who get tuberculosis. Indian, British and Canadian researchers published their study in the British medical magazine, The Lancet.
The study says smoking causes about seven-hundred-thousand deaths each year just in India. Most of the victims are men under seventy years old. The researchers say these men lost about twenty years of life because of smoking.
Besides tuberculosis, people who smoke or breathe other people's smoke may get lung cancer, heart disease and other disorders. Tobacco is also dangerous to the unborn children of women who smoke during pregnancy.
The study from India found that smokers were four times as likely to die from tuberculosis as non-smokers.
The study looked at men who died of T-B before they were seventy years old. It found that nearly eighty percent had been smokers.
The researchers say smoking can lead to tuberculosis whether a person smokes regular cigarettes or smaller, handmade ones known as bidis.
Tuberculosis can sometimes stay in a person’s lungs for a long time without making them sick. This is called latent T-B. Smoking can cause latent T-B to become active.
If tuberculosis has already damaged the lungs, experts say smoking will make that person feel even worse. If a person is being treated for T-B, smoking will also make the treatment take longer.
Doctor Richard Chaisson is a researcher at the Johns Hopkins University in Baltimore, Maryland. He says antibiotic medicines may be able to cure T-B in smokers. But smokers may continue to cough and have a hard time breathing even after their T-B is gone.
Doctor Thomas Frieden is a tuberculosis researcher in New York City. He told the New York Times newspaper that Asian women are now the number one market for the tobacco industry. Tobacco companies use posters and other public messages to urge more women to smoke.
World health officials worry that diseases caused by smoking will increase as more women start. These officials say countries should ban advertising messages for tobacco.
The researchers in India studied men, because mostly men smoke in that country. This is true in most developing countries.
But the situation is changing. A new report says young girls now smoke cigarettes almost as much as boys. The results also show that girls and boys use other tobacco products at similar rates. These include spit tobacco, bidis and water pipes. In fact, girls and boys often use these products at rates as high or higher than cigarettes.
The findings are from the Global Youth Tobacco Survey. That study involved over one million young people from more than one-hundred-fifty countries. The report came out during a conference in Helsinki, Finland, last month.
And, just last week, a study published in The Lancet said smoking killed almost five-million people in two-thousand. Researchers said most of the deaths were from heart and lung diseases.
The United States Food and Drug Administration has approved a new birth control pill. It is called Seasonale. Drugs to prevent pregnancy have traditionally been designed for a normal menstrual cycle of twenty-eight days. But women who use Seasonale will have a period of bleeding about every three months instead.
They will take pills that contain hormones for eighty-four days. Then for seven days they will take pills that contain no hormones. Their period will happen during this time.
Seasonale is expected to go on sale at the end of October. It contains progestin and estrogen. Birth control drugs commonly use these two hormones. Barr Laboratories makes the new drug.
The Food and Drug Administration says possible side effects of Seasonale are similar to those of traditional birth control drugs. These include an increased risk of heart attack and stroke.
Warnings on Seasonale say that smoking increases the possibility of serious side effects. Doctors say women who use birth control pills should not smoke. This is especially true of women older than thirty-five.
The Federal and Drug Administration says women should discuss any use of birth control drugs with their doctors.
The Gila (HE-luh) monster is a poisonous lizard. It lives in the desert of the American Southwest and in Mexico. Gila monsters eat as few as four times a year.
A chemical in the liquid produced in their mouth stops their hunger at other times. Now researchers say this chemical may also work in people, to treat diabetes.
Two companies, Amylin Pharmaceutical and Eli Lilly, have made their own version. They call the experimental drug exenatide.
People with diabetes have high levels of sugar in the blood. Their bodies lack insulin or cannot use this hormone effectively. Insulin helps the sugar, called glucose, enter cells for use as fuel.
Too much glucose in the blood damages the kidneys, eyes and nerves. It stops blood flow to the legs. And it increases the chance of heart disease and stroke.
The researchers tested exenatide on one-hundred-fifty-five patients with type two diabetes. Type two develops in adults and children when the body is not able to use the insulin it produces. The patients received two injections of exenatide every day for twenty-four weeks.
The researchers say sugar levels dropped to within target levels in forty-four percent of the patients. These people also lost more than three kilograms each. The scientists say the chemical suppressed hunger. They say it also caused the body to produce insulin in reaction to high sugar levels.
The researchers reported their work at the International Diabetes Federation Congress in Paris. If the drug passes more tests, the two companies say they could ask as early as next year for government approval.
SCIENCE IN THE NEWS was written by Karen Leggett, Jerilyn Watson and Nancy Steinbach. Our producer was Cynthia Kirk. 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.