Question

Write short notes on:

1. Amoebiasis
2. Malaria
3. Guinea worm disease
4. Cancer

Answer 1

1. Amoebiasis:

• Amoebiasis disease is also called as Amoebic dysentery.
• This is caused by a protozoan called Entamoeba histolytic.

Symptoms:

• In this disease, the pathogen in its trophozoite stage enters in the intestinal wall and secretes tissue decomposing enzymes which cause disintegration of cells.
• This results in small mucus-filled ulcers in the affected area.
• The ulcers bursts in the lumen of the intestine and release mucus which comes out along with the faces.
• The patient does not suffer from fever, however, he develops diarrhoea with abdominal cramps throughout the day.
• Some times blood also comes out along with stool. Patients become very weak.
• Mode of Infection: It spreads through food, water and flies.
• Prevention: For prevention from this disease we, boiled water, we must not consume uncovered food.
• Treatment: For the treatment of this disease Amitine, Fusegilin, metronidazole medicine are available.

2. Malaria Fever:

• This disease is caused by various species of Plasmodium which are as follows:
  1. Plasmodium vivax: Most common
  2. Plasmodium falciparum: Most dangerous
  3. Plasmodium malaria
  4. Plasmodium ovule
• The transmission of the disease is through biting of female Anopheles mosquito.
• Life Cycle of Plasmodium:
• The life cycle of Malaria parasite is digenetic. It is divided into three phases:

Schizogony Asexual  ⇒ Human liver cells & RBC.

Gamogony 3 Sexual ⇒ Begins in Man and completes in female Anopheles.

Sporogony ⇒ Asexual; Stomach of female Anopheles.

The Schizozogony is further divided into four phases:

• Preerythrocytic phase: Human Liver Cells.
• Exoerythrocytic phase: Human Liver Cells.
• Erythrocytic phase: Human RBC.
• Postertythrocytic phase: Human liver cells.
• Infective Stage: The infective stage in Man is sporozoite.
• Through biting of female Anopheles mosquito, sporozoite of Plasmodium enters in the blood and multiplies in the liver cells and red blood corpuscles.
• Haemozine is produced which results in Shivering, Chills and Fever.
• The parasite in its gametocyte phase enters in the mosquito when a mosquito bites an infected person.
• Further maturation of the parasite occurs in female Anopheles.
• Male & Female gametocyte through the process of gametogenesis produces male and female gametes.
• The gametes fuse and to form a zygote. The zygote divides and forms new sporozoites that migrate to the salivary gland of the mosquito.
• When the mosquito bites a person, the sporozoites enter his body. For the treatment of this disease medicines containing antimony compounds are used.

Symptoms:

Release of haemozoin along with merozoites causes malaria symptoms or paroxysm viz.,

• Rigour stage: Patient experience chill and shivering.
• Fibril stage: Body temperature rises to 104-106°F.
• Defervescent stage: Profuse sweating. It occurs 6hrs. after rigour stage.

Medicines:

• Quinine is the oldest known medicine for the treatment of malaria fever. It is obtained from the bark of the Cinchona tree. This tree is found in Peru, Shri Lanka. Java, India etc.
• Other useful medicines are Nivaquin, Resochin, Camaquin, Chloroquine, Paludrin, Plasmaquin, Daraprim, Mapacrine etc. Sulfadoxine & Pyrimethanine are the new & most effective medicines. Nowadays a single dose of sulfadoxine 750 mg. & Pyrimethamine 37.5 mg. is given.

Prevention:

• According to National malaria eradication programme (NMEP), malaria control involves three methods viz. destruction of mosquitoes, prevention from infection & treatment of patients.
• Destruction of mosquito larvae using fishes is called as biological control of malaria.
• Stickle back, Gambusia, Minnows, Trout, Channa etc. are some Larvicidal fishes.
• Allethrin is the most recent mosquitocidal chemical. 3.6% of allethrin is used in various trademarks like All out, Goodnight, Jet etc. Other common insecticides are Pyrethrum, BHC, DUT, Nephella etc. –

3. Dracunculiasis:

• This disease is caused by a worm called Dracunculus. This pathogen is also called as Guinea Worm or Naru worm. In humans, this worm resides beneath the layer of subcutaneous tissues of arms, legs and shoulder skin.

Symptoms:

• In the effort to release the embryo, the bearing female tries to move out of the skin. The area of skin from where it attempts to move out suffers from itching and inflammation.
• The poisonous substances released by the female worm forms small ulcer or blister through which the posterior portion of the female worm comes out to release young ones. Local inflammation, swelling and pain are associated with this process. Blisters get cured in a few days.

Treatment:

• For the treatment, the worm is removed through surgery. In villages, the worm is removed with the help of a wooden stick.
• Villages do it very carefully by wrapping and pulling the worms which are peeping out of the skin on the wooden stick. In this process, there are many chances of breaking of the worm inside the body.

4. Cancer:

• It is a complex disease which may occur in any body part.
• Cell division in the human body is a normal feature but as and when the regulatory process of the division gets disturbs, the cells start to divide in an uncontrolled manner. i.e. cancer is a stage when “cell gets mad”.
• This results in the formation of a cellular lump which is called as Tumour.
• Lung cancer is the most common in human beings.
• In women, mammary cancer is most common.