Oseltamivir (Tamiflu) treats influenza by inhibiting viral neuraminidase. The consequence of this inhibition on viral spread is:

• A Newly formed virions remain attached to the host cell surface (via hemagglutinin-sialic acid bonds), preventing release and spread to new cells ✓
• B Neuraminidase inhibition prevents fusion of influenza envelope with endosomal membranes, blocking viral entry
• C Inhibition of neuraminidase prevents cleavage of the viral hemagglutinin precursor needed for infectivity
• D Neuraminidase inhibition prevents uncoating of viral RNA inside the host cell nucleus

Explanation

After replication, new influenza virions bud from the host cell but remain attached via hemagglutinin binding to sialic acid residues on the host cell membrane. Viral neuraminidase cleaves these sialic acid bonds, releasing virions to infect new cells and spread mucus. Oseltamivir's neuraminidase inhibition traps virions on the cell surface, preventing release and limiting spread. Viral entry is blocked by M2 ion channel inhibitors (amantadine); hemagglutinin cleavage requires host proteases.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.