The following table shows certain diseases, their causative organisms and symptoms.
| Diseases | Causative organisms | Symptoms |
| I. Filariasis | A | Inflammation of lymphatic vessels |
| II. Typhoid | B | High fever, stomach pain |
| III. C | Rhinoviruses | Nasal congestion and discharge |
| IV. Ascariasis | Ascaris | D |
The correct option regarding A, B, C and D is:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A–Wuchereria, B–Salmonella typhi, C–Common cold, D–Internal bleeding, fever, anaemia
A (causative organism of filariasis) — this is Wuchereria. The filarial worms W. bancrofti and W. malayi cause a slow, chronic inflammation of the lymphatic vessels of the lower limbs (elephantiasis or filariasis).
B (causative organism of typhoid) — this is Salmonella typhi, a bacterium that enters the small intestine through contaminated food and water. Sustained high fever and stomach pain are among its symptoms.
C (disease caused by rhinoviruses) — this is the common cold. Rhinoviruses infect the nose and respiratory passage but not the lungs, causing nasal congestion and discharge.
D (symptoms of ascariasis) — these are internal bleeding, fever and anaemia. Ascaris, the common round worm, lives in the intestine; muscular pain and blockage of the intestinal passage are its other symptoms.
NCERT Extract:
Common Diseases in Humans – “… Salmonella typhi is a pathogenic bacterium which causes typhoid fever in human beings. These pathogens generally enter the small intestine through food and water contaminated with them and migrate to other organs through blood. Sustained high fever (39° to 40°C), weakness, stomach pain, constipation, headache and loss of appetite are some of the common symptoms of this disease.”
Common Diseases in Humans – “… Rhino viruses represent one such group of viruses which cause one of the most infectious human ailments – the common cold. They infect the nose and respiratory passage but not the lungs.”
Common Diseases in Humans – “… Ascaris, an intestinal parasite causes ascariasis. Symptoms of these disease include internal bleeding, muscular pain, fever, anemia and blockage of the intestinal passage. … Wuchereria (W. bancrofti and W. malayi), the filarial worms cause a slowly developing chronic inflammation of the organs in which they live for many years, usually the lymphatic vessels of the lower limbs and the disease is called elephantiasis or filariasis (Figure 7.2).”