(A) Ganciclovir
(B) Tamiflu
(C) Interferon gamma
(D) Neutralizing antibody
Neutralizing antibodies selectively propagate escape variants from mixed influenza populations by inhibiting wild-type viruses. This article explains Q.71 with the correct answer and all options for virology exam prep.
Correct Answer
The correct answer is (D) Neutralizing antibody.
Antibodies against the parental strain neutralize common viruses in mixed populations, allowing rare antigenic variants to replicate selectively. This in vitro escape mutant selection mimics natural evolution, identifying potential vaccine escape strains.
Option Breakdowns
(A) Ganciclovir
Ganciclovir inhibits herpesvirus DNA polymerase, ineffective against RNA viruses like influenza.
No selective pressure on influenza variants.
(B) Tamiflu
Tamiflu (oseltamivir) blocks influenza neuraminidase, preventing all strains from releasing progeny equally.
Inhibits propagation non-selectively.
(C) Interferon gamma
IFN-γ is an antiviral cytokine inducing broad host resistance, not variant-specific selection.
Blocks all influenza replication indiscriminately.
(D) Neutralizing antibody
Specific antibodies bind hemagglutinin of dominant strains, permitting only antibody-escape variants to propagate.
Standard method for antigenic cartography and vaccine strain prediction.
| Option | Mechanism | Selective Propagation? | Matches Q.71? |
|---|---|---|---|
| (A) Ganciclovir | DNA pol inhibition | No (wrong virus) | No |
| (B) Tamiflu | NA inhibition | No (all strains) | No |
| (C) IFN-γ | Host antiviral state | No (broad block) | No |
| (D) Neutralizing Ab | Antigenic escape | Yes (variants only) | Yes |
