Class 12th Biology 2012 Set1 Outside Delhi Board Paper Solution
Question 18
Name the bacterium that causes typhoid. Mention two diagnostic symptoms. How is this disease transmitted to others?
Answer
The bacterium that causes typhoid is Salmonella typhii.
Two symptoms of typhoid are-
(i) Constipation
(ii) Sore throat
Typhoid is usually transmitted by water or food. People who are infected excrete live bacteria in their feces and urine. They are usually contagious for a few days before any symptoms develop, so they don't know they need to take extra precautions. If they don't wash their hands properly, the typhoid bacillus can be transferred to food or water and from there to another person. Also, it can be spread directly from person to person via contaminated fingers.
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