Organisms Affecting Human Health Part 4

Organisms Affecting Human Health Part 4

20. 9 some common diseases
Tuberculosis (TB)

Tuberculosis is worldwide but is most common in tropical areas. Tuberculosis takes a long time to develop but depends mainly upon the health and state of the people. Most common TB. Is of the lungs, apart from TB of intestine, bones etc.

Causative organisms

A bacillus (bacterium) mycobacterium is the cause of tuberculosis. There are several species of mycobacterium causing different types of TB. The bacterium is very resistant and can remain alive for several months under unfavorable circumstances but reproduces when circumstances become favorable. Toxins produced by the bacteria cause the disease. Te disease is spread by droplet infection (cough, sneezing, deep breath and by spitting) and unboiled milk. Over-crowding and humid and dirty conditions also promote the spread of disease.

Treatment and control
The disease can be controlled by;

1. Vaccination of BCG to the children to encourage the development of antibodies.
2. Revaccination after three to five years.
3. Use of thoroughly boiled or pasteurized milk.
4. By keeping patients in isolated or pasteurized milk.

Cholera

Cholera is mainly found in Asia and commonly spreads in humid condition. Disease begins with fever, diarrhea and vomiting, accompanied by severe abdominal pain. Severe attacks result in dehydration and death of the patient.

Causative organism

Cholera is caused by a comma-shaped bacterium called vibro cholera with a flagellum which enables it to swim in water. Vibro cholera is ono-caplulated and cannot withstand dry condition. It is water born. The disease is spread by the use of contaminated water and food (fig. 20.19).

Control over the disease

1. By the use of boiled or chlorinated water.
2. By keeping or food covered to avoid its contamination.
3. By injecting cholera vaccine which gives an active artificial immunity for six month.
4. By keeping infected persons in isolated places as the bacteria are transmitted by flies as well as by water.
5. Good sanitation is required to prevent the contamination of water.

Fig. 20.19) disease cycle of cholera

Treatment

Saline solution is continuously injected into vein of patient to maintain the body fluid balance. This does not kill the bacteria but enables the patient to overcome the effects of dehydration and allow his own body to fight the disease. Drugs (antibiotics) are also given to kill the bacteria.

Bacillary dysentery

Bacillary dysentery is a food-born disease. Symptom of the disease is severe pain in the lower abdomen. It is followed by diarrhea and fever. There is appearance of mucous and blood (in the case of severe attack) in the stools.

Causative organism

Bacillary dysentery is caused by rod-shaped (bacilli) bacteria. The bacteria are motile and are found in the faeces of patients in large numbers. The disease is spread by the use of contaminated food and from unwashed hands after using lavatory.

Control over disease

1. By protecting cooked and uncooked food from houseflies.
2. By careful washing of hands after using toilet.
3. By adopting proper methods of sanitation to prevent flies from sitting on human faeces and breed there.

Treatment

1. The patient should take rest and eat no solid food for a day or two.
2. Patient should be given plenty of water and ORS (Oral Rehydrate Salt) to prevent dehydration.

Proper medicine should be given.