19. You are comparing two strains of the dengue fever virus found in India- one

Question

19. You are comparing two strains of the dengue fever virus found in India- one originated from the Americas and one originated in Thailand. If there is higher genetic variation in the Thailand strain of the virus than in the American strain, what does this indicate about when dengue fever first entered the human population in these regions? A) Dengue fever entered the human population in Thailand earlier than in the Americas. B) Dengue fever entered the human population in the Americas earlier than in Thailand. C) Dengue fever entered the human population at the same time in Thailand and the Americas. D) We cannot tell from this information when dengue fever entered the human population in either area

Explanation / Answer

A virus undergoes genetic variation majorly through changing surface proteins. It does so to bypass the immune system of the host. As the host starts producing antibodies against the surface proteins of the virus to evade the infection from the body by the action of antibody mediated phagocytosis or complement activation. In such a situation the virus starts evolving by genetic variability. Thus the virus with more genetic variation would have entered the population before the other because that virus had to undergo more changes in more time to evade the immune system of the host.

A is correct answer.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.