Fri, 24 Mar 2000

Tuberculosis can strike anyone

By I. Christianto

JAKARTA (JP): As the world enters the third millennium, some diseases continue to evolve while others remain the same "killing machines" they have been for hundreds, even thousands, of years.

Physician and Pneumophthisiologist Muherman Harun said tuberculosis, known as the White Scourge, was an ancient disease.

"TB's been known for some six thousand years. Archaeological studies found skeletal remains which are characteristic of tuberculosis in an Egyptian mummy," he said.

Phthisis, or consumption, is a wasting disease, according to the father of medicine, Hippocrates of Greece, who named the disease, Harun said.

The symptoms of tuberculosis are high fever, a continuing cough, blood in the sputum, the deterioration of muscles, exhaustion and, eventually, diarrhea, which signals the terminal stage of the disease (as the disease moves from the lungs to the abdomen).

Harun said that from 1800 to 1865, the spread of TB was strongly influenced by poor social conditions in Europe. At that time, there was a very high number of deaths caused by TB.

"At the time, the disease was regarded as 'People's Enemy No. 1'. Particularly in the bigger cities of Europe, where industry was rapidly developing, TB took a heavy toll among the people."

He reiterated that TB was not only confined to the poor. "The disease also killed the social elite, as recorded in European literature. They included Henry VII of England (1509), Louis XIII of France (1643) and French philosopher Rousseau (1778)."

Unveiled

The first and most important milestone in the history of tuberculosis was laid by German physician Robert Koch.

On March 24, 1882, Koch revealed that tuberculosis was caused by a bacillus he named Mycobacterium tuberculosis. The bacilli can be transmitted from man-to-man, animal-to-animal and man-to- animal, and vice versa. The most important source of infection was sputum, which in cavitary lung tuberculosis can harbor hundreds of thousands bacilli.

In 1906, two French doctors, Calmette and Guerin, prepared a vaccine from attenuated tubercle bacilli obtained from cows with tuberculous. The vaccine is known as BCG (Bacillus Calmette- Guerin).

Harun said an important tool for the detection of tuberculosis was introduced by the German W.C. Roentgen (1845-1923), the inventor of the X-ray. Chest X-rays play a pivotal role in any TB control program.

"The principal tools for the diagnosis of TB comprise a microscopic examination of the sputum and an X-ray examination of the lungs, apart from a careful family history and physical examination," he said.

Prevention

The World Health Organization (WHO) reported that one-third of the world population has been infected with the TB bacillus. Those people who do not receive treatment can infect up to 15 other people per year.

Harun said Riley proved TB infection was an air-borne infection.

A person is said to have open TB if tubercle bacilli are present in the sputum, as shown by a microscopy. If the microscopy is negative, the patient is not contagious, he said.

"However, extrapulmonary TB (affecting organs other than the lungs, like cervical lymphnodes and meningeal/cerebral TB, and TB of the intestines, urinary tract and reproductive organs) does not cause infection. The same holds true for childhood or Primary TB."

Infection with tubercle bacilli usually occurs when a person with positive sputum coughs or sneezes without covering their mouth and nose. With every cough, numerous small sputum particles containing bacilli are spread into the air. The larger particles are grounded and pose no risk of infection. But the smallest of the sputum particles, called droplet nuclei, float in the air and are capable of settling themselves in the alveoli (the smallest, tiniest lung unit), transporting the bacillus to cause infection.

This implies that sputum found on the handkerchiefs, clothes, utensils and books of a TB sufferer, albeit contaminated with bacilli, are by no means sources of infection. Because it is only the floating droplet nuclei that harbor the tubercle bacillus which settle on the alveoli and cause infection.

A TB patient's food or drink obviously cannot transport bacteria into the lungs. These bacteria will pass into the gastro-intestinal tract.

Harun said that after completing treatment, TB patients may have residual lesions on their lungs, which will not disappear even if treatment is prolonged for life. A cure means that the disease is halted, and may remain so for life. A relapse can occur if a person is reinfected with TB bacilli, or if a person's immune system is compromised, allowing dormant bacilli to become active.

After completing treatment, the expectation is that there will be no relapse, he said.

"To prevent TB, one must have a healthy lifestyle: no smoking, physical exercise, healthy food, eliminating all sources of TB infection (treat sputum-positive cases)," Harun said.

He added that the BCG vaccination could not prevent infection but could prevent the fatal development of TB in children, like meningitis.