PATHOLOGY MCQ
LYMPHO RETICULAR SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Only allergens create lifetime immunity.
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Viruses change quickly and frequently.
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Viruses do not create immune responses.
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Allergens mutate frequently.
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Detailed explanation-1: -Another study6 in Qatar suggests that if the virus doesn’t change, infection-based immunity against reinfection can last up to three years. But that immunity can fade faster if the virus mutates. The authors studied data from unvaccinated people who were infected with a pre-Omicron variant.
Detailed explanation-2: -The major advantage to passive immunity is that protection is immediate, whereas active immunity takes time (usually several weeks) to develop. However, passive immunity lasts only for a few weeks or months. Only active immunity is long-lasting.
Detailed explanation-3: -In many cases, acquired immunity is lifelong, as with measles or rubella. In other instances, it can be short-lived, lasting not more than a few months. The persistence of acquired immunity is related not only to the level of circulating antibody but also to sensitized T cells (cell-mediated immunity).