Infectious Disease

Which of the following pathogens have made a cross-species transfer to humans?

• influenza virus

• West Nile virus

• both of these

Most infectious diseases are transmitted through

• water

• soil

• people

Which of the following is an environmental change that may result in more pathogens making a cross-species transfer to humans?

• polluting water with lead

• destroying habitats

• soil erosion

Human immunodeficiency virus is considered an emerging virus because it

• had been controlled until recently

• developed from two other viruses

• was previously unknown

Toxicology is the study of the harmful effects of

• substances on organisms

• pollutants in the environment

• antibiotics on viruses

After an outbreak of an illness, scientists use epidemiology to try to find

• the origin of the disease

• how the disease spreads

• both of these

An estimate of the probability of a negative effect caused by a substance is a

• risk assessment

• response assessment

• dose-response curve

How do viruses that develop in an animal species end up affecting humans?

• cross-species transfer

• eating of infected meat

• all viruses affecting humans develop in humans

How can infectious disease spread?

• from person to person

• by drinking water that contains a pathogen

• both of these

An organism that transmits a disease-causing organism to humans is a(n)

• host

• vector

• pathogen