Which of the following diseases usually spread through milk?

Which of the following diseases usually spread through milk?
(i) Plague
(ii) Poliomyelitis
(iii) Typhoid
(iv) Diphtheria

None of the above are spread via milk as a rule. Plague is spread by the plague virus, carried by fleas who bite infected victims and then a new person. Polio is spread strictly from human to human, it has no other vectors, which is why they were so sucessful at eliminating it. It used to spread through contaminated water, sewage contaminated as a rule- but it could be spread in undertreated pools and such. Infected persons shed the polio virus in just about all their secretions. Typhoid is also spread only human to human, there are no animal vectors. It spreads through water contaminated by sewage primarily, although humans can be carriers and spread it to others in food. Diptheria has been documented as spread in unpasteurized milkl, but people are still the only known reservoirs of the infection. It is primarily spread via airborne droplets or contact with the infected nasal secretions of an ill person. It would likely be introduced into the milk at the dairy, and as it is not pasteurized it could then infect those who drank it. But when the milk came from the cow, it was not contaminated- it still must be contaminated by an ill person. So none of the diseases are primarily spread through milk, they are all still primarily transmitted person to person, as they have no other vectors. Just different means of transmission.

Answer is Item (iii) Typhoid. S. typhi are spread by contaminated food, drink, or water. Following ingestion, the bacteria spread from the intestine via the bloodstream to the intestinal lymph nodes, liver, and spleen via the blood where they multiply.

Typhoid
Diphtheria

Diphtheria was often spread through contaminated dairy products before Pasteurisation became commonplace.

Good luck with your homework.

Tuberculosis can develop after inhaling droplets sprayed into the air from a cough or sneeze from an infected person and it can also spread through infected sputum and there is a form spread through milk from infected cows.

Never drink unpasteurised milk. If in doubt, boil it before drinking. There is a vaccination (BCG) which can give a valuable degree of protection, particularly in children.

Ask your doctor.