Why Do We Fall ill?

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6 Infectious Diseases II

Diseases Caused by Bacteria

1. Tuberculosis (T.B.)

  • Tuberculosis was first discovered by German scientist Robert Koch in 1882.
  • T.B. is an infectious disease which is communicated from one person to another either directly or indirectly.


Following symptoms are observed in the patient:

  • Feeling of sickness and weakness.
  • Loss of appetite and weight.
  • Typical fever pattern and night sweats


  • Vigorous public health measures are the best method of prevention.
  • It is essential to avoid over-crowded places to prevent the disease.
  • Provision of good ventilation and better nutrition also helps to reduce the incidence of the disease.
  • Immunisation with BCG or Bacillus-Calmette-Guerin vaccination prevents tuberculosis.


  • The tuberculosis can be cured by the following Isoniazid, Rifampicin, Pyrazinamide, Ethambutol and Streptomycin

2. Cholera

  • Cholera is an acutely infectious and fatal disease
  • It is more common during overcrowded fairs, festivals and after floods.
  • Sometimes cholera occurs in epidemic
  • It is caused by the bacteria called bacterium vibrio cholera.
  • It is usually transmitted by flies, contaminated water and food.


  • Watery diarrhea (i.e., rice-water like stools). It is generally painless.
  • Vomiting is effortless without nausea.
  • Loss of several litres of fluid from patient’s body within hours resulting in dehydration, muscle cramps and weight loss.
  • Great loss of mineral salts and body fluid. This leads to kidney failure.
  • Eyes of patient become shrunken.


  • Persons should be immunised by standard cholera vaccine. One dose of immunisation lasts for about six months.
  • It is essential to carry boiled water and cooked food in the cholera prone areas.
  • Proper care should be taken in personal hygiene and good sanitation in the community.


  • To prevent dehydration, therapy with Oral Rehydration Solution (ORS) should be done immediately.
  • ORS solution contains around 3.5 g sodium chloride, 2.5 g sodium bicarbonate, 1.5 g potassium chloride, 20 g glucose, 40 g sucrose in one litre water. Taking small sips of ORS solution at intervals prevents dehydration of the patient.
  • Immediate medical advice is required

3. Typhoid

  • Typhoid is the most common communicable disease in India.
  • Typhoid fever is common in humans between the age 1 to 15 years.
  • It is caused by a rod-shaped and motile bacterium, called Salmonella typhi.


Symptoms of typhoid are the following:

  • Headache and typhoid fever which rises maximum during the afternoon. The temperature increases each day during the first week.
  • High fever during the second week. The fever gradually declines during 3rd and 4th
  • In a nutshell typhoid symptoms include continuous fever often with delirium (disorder of the mind), slow pulse, tender and distended abdomen, diarrhea with water-green stools and eruption of rosy spot (rash) on the body of the patient.


  • Ensure proper sanitation and disposal of faecal matter to prevent the infection.
  • TAB- vaccination provides immunity for 3 years. (TAB vaccine contains killed typhoid bacilli and paratyphoid organisms-salmonella paratyphi A and B).
  • Oral vaccine named Typhoral also prevents typhoid.

4. Diarrhoea

  • Diarrhoeal disease forms a group of intestinal infection, including food poisoning.
  • Other symptoms of this disease include decreased appetite, vomiting and nausea.


  • Frequent loose motions and vomiting which leads to dehydration.
  • Dehydration (loss of water from the body tissue). This makes the patient dangerously ill in a very short time. Most of the infant deaths due to diarrhea can be prevented by ensuring that dehydration does not take place through stools and vomiting.
  • In cases of dehydration, the patient becomes irritable, eyes appear sunken, nose is pinched and the tongue and the inner side of cheeks appear dry.
  • Sudden weight loss, weak pulse, deep breathing and fever or fits.


  • Eatables must be covered to prevent their contamination.
  • Fruits and vegetables must be washed properly before use.
  • Proper personal hygiene is essential. Hands should be washed with soap and water before eating any food.
  • Stale food should not be consumed.
  • It is also important to maintain community hygiene


  • It is necessary to ensure complete bed rest till the illness is fully controlled.
  • Anti-microbial drugs and anti-diarrohea agents should be used to treat diarrhoea.
  • In case of frequent vomiting, liberal amount of fluids loaded with electrolytes, should be provided orally to the patients.
  • Pulp of boiled unripe banana along with required amount of salt, turmeric powder and lime is helpful in controlling the diarrhoea.
  • Husk of isabgol seed (plantago ovata) with water or curd provides good relief to patients.
  • Saline drip may also be given intravenously to maintain fluid and electrolytes in the body. Alternatively oral rehydration solution (ORS) may be periodically given to the patient.
  • Dilute soups and dals, rice-water and butter-milk can also be given to the child in order to compensate for the loss of water.

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