Which statement about viruses is true?

Which statement about viruses is true?

• A. Most viruses infect lab animals but most do not cause clinical disease
• B. All viruses cause clinical disease
• C. Viruses are larger than bacteria
• D. Viruses can be treated with antibiotics

Answer: (A)

In virology, it’s important to distinguish infection from disease and to recognize the limits of antibiotics. The statement that most viruses infect lab animals but most do not cause clinical disease reflects how research uses animal models to study viral infection, but many infections in those animals are subclinical or controlled by the host immune system, so illness doesn’t always occur. This shows that infection does not automatically equal disease. The other ideas don’t fit: not all viruses cause clinical disease, viruses are much smaller than bacteria, and antibiotics do not treat viral infections.

In virology, it’s important to distinguish infection from disease and to recognize the limits of antibiotics. The statement that most viruses infect lab animals but most do not cause clinical disease reflects how research uses animal models to study viral infection, but many infections in those animals are subclinical or controlled by the host immune system, so illness doesn’t always occur. This shows that infection does not automatically equal disease. The other ideas don’t fit: not all viruses cause clinical disease, viruses are much smaller than bacteria, and antibiotics do not treat viral infections.