Chapter 13, Problem 10MCQ

Summary Introduction

Introduction:

Viruses are tiny organisms, which invade healthy cell and acquire infections or diseases. They usually infect the particular type of cell (influenza viruses affect only upper respiratory cells). The viral infections are communicable diseases which are transmitted from one to another. Viruses destroy the antiviral protein, such as cytotoxic T lymphocytes (CTLs) to suppress the immune system.

Onset of viral infection shows the disease symptoms at early or latent period. However, some viruses do not show any symptoms but it cause serious disease which may lead to fatal.