21. Principles of Disease

How is the transmission of the amoeba Entamoeba different from the transmission of the amoebas Acanthamoeba and Naegleria?

For which of the following reasons are most animal poxviruses unable to infect humans?

a. Affected animals are not in frequent contact with humans.

b. The human immune system makes it impossible for the foreign viral particles to

reproduce effectively.

c. Attachment to human cells is unlikely.

d. Human cells lack the necessary enzymes for infection.

The initial flat, red skin lesions of poxviruses are called____.

a. macules

b. papules

c. pustules

d. pocks

Which of the following statements is true concerning variola major?

a. It carries a mortality rate of less than 1%.

b. It affects internal organs before appearing on the skin.

c. The causative virus has been totally eradicated from Earth.

d. The skin lesions it causes are smooth, waxy, tumorlike nodules on the face.

Which of the following herpesvirus infections would be potentially most serious?

a. A whitlow

b. Ocular herpes

c. Shingles

d. Cytomegalovirus in a fetus

A man experienced a laboratory accident in which he was infected with adenovirus. What signs or symptoms might he exhibit?

a. Sore throat

b. Headache

c. Pinkeye

d. All of the above

Which of the following is an inflammatory condition of the liver?

a. Fifth disease

b. PML

c. Seed warts

d. Hepatitis

Which of the following statements is false?

a. B19 virus is the primary parvovirus of humans.

b. Erythema infectiosum is caused by a parvovirus.

c. In children, parvovirus infections are accompanied by a high mortality rate.

d. Parvovirus infection in humans results in infectious reddening of the skin.

A distinguishing feature of poxvirus is _____.

a. its large size

b. a polyhedral capsid

c. the type of RNA it contains

d. the production of several types of warts

Monkeypox has been diagnosed in several humans in the Democratic Republic of the Congo. What might be recommended to prevent further risk of infection?

a. Catch the monkeys for inoculation with monkeypox vaccine.

b. Remove infected tissues from humans with chemicals, by surgery, or by freezing.

c. Reinstate smallpox vaccinations for the country's population.

d. The diagnosis must have been incorrect because humans are unaffected by

monkeypox.

Being habitually careful not to touch or rub your eyes with unwashed hands would reduce your risk of contracting_____.

a. chickenpox

b. infectious mononucleosis

c. seed warts

d. a cold

Human herpesvirus 2 _____.

a. can cause genital herpes

b. may infect a baby at birth

c. causes about 10% of cold sores

d. all of the above

Epstein-Barr virus _____.

a. can be asymptomatic

b. causes mononucleosis

c. can cause cancer

d. all of the above

The Smith family seems to get fever blisters regularly. Suggest an explanation for this observation.

What was the difference in the effects of variola major and variola minor?