DEAR DR. DONOHUE: What can you tell me about tuberculosis? When I was 12, I was exposed to it and got the germ. I had to take pills for a year. I am 50 now and feel I have nothing to worry about. But now someone tells me I am still at risk, so I keep my past quiet. I never cough like my uncle who had it did. – B.B.

Tuberculosis has been a scourge to humankind for thousands of years. In the 19th century, it was responsible for one-quarter of all adult deaths in Europe. Not until 1946, with the discovery of the antibiotic streptomycin, was there effective treatment for it. Before then, all countries had sanitariums, where TB patients took the rest cure without much improvement in their illness. Now we have many effective antibiotics that can kill the TB germ, but, even now, more than 2 billion people are infected with it.

The TB germs spread mainly in droplets coming from the mouth of an actively infected patient who coughs, sneezes or even just talks. People nearby inhale the germs, which settle in the lungs. From the lungs they can spread to kidneys, bones, lymph nodes and the coverings of the brain.

You were infected with the TB germ. You never had the illness tuberculosis. You were treated with an antibiotic that kills the germ. You probably would not have come down with active TB even 38 years ago, but the germ could have lived on in your lung and become active again later in life. Your treatment has eliminated that possibility. The risk of you getting TB or spreading it is as close to zero as anything in life can be. You don’t have to keep your past experience a secret.

The big problem with TB today is the emergence of TB strains that are resistant to many of the anti-TB drugs. We still have medicines that can eradicate these strains, but we are at a point where a strain might arise that is resistant to all drugs. Careful tracking of infections and careful monitoring of compliance with treatment can lessen the chances for an epidemic of resistant TB.

DEAR DR. DONOHUE: Growing up and also as an adult, I and my family never drank water unless we were thirsty. In fact, at the place where I worked, there was no water fountain.

Now we are told to drink eight glasses of water every day, whether we are thirsty or not. When I do this, I am always going to the bathroom. I have always been very healthy. Now, in my 80s, I am tired of getting up at night. That does not happen if I drink as I did when I was a child. Please advise. – K.H.

I have good news for you, K.H., and you can have uninterrupted sleep once again. You don’t need to drink eight glasses of water a day. That’s an idea based on erroneous information. We get fluid from all the liquids we drink, including caffeine-containing beverages. Solid foods have much liquid in them. Some fruits, for example, are mostly water – watermelon, oranges, grapefruits and grapes.

Go back to your childhood days. Drink when you’re thirsty.

I had a high-school teacher who flooded himself with water to remove “toxins” from his body. He didn’t pass a water fountain without drinking unbelievable volumes. The class pastime was betting on how many minutes short of a regular class period he would last until he had to bolt for the restroom.

DEAR DR. DONOHUE: Would you discuss ultrasound? Is it dangerous? Can you get too much of it? – B.M.

ANSWER: Ultrasound takes pictures of the body’s interior with sound waves. They bounce off the different tissues and are reflected to a sensor, where images are produced. These are the same kind of waves we generate by speaking. We don’t hear ultrasound waves because they’re above the range of human hearing.

No damage is done to any part of the body from ultrasound. It is not dangerous. You can’t get an overdose of it.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from

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