BIO 208 Chapter 2 InQuisitive Questions

What are factors that lead to increasing rates of mosquito-borne tropical diseases?

- global warming - tropical deforestation - urban sprawl

When an organism is newly discovered, often researchers will investigate several different traits to determine if this new organism is capable of causing disease. Which traits would be particularly useful to researchers wanting to describe the virulence of a newly discovered microbe?

- lethal dose 50% (LD50) - infectious dose 50% (ID50)

Most infections go through a similar course of several stages that are characterized in this figure. During which phases is the number of microbes present increasing faster than the immune response to those microbes?

- prodromal phase - illness phase

A child spends time in the woods and encounters a raccoon. She is bit and is sent to the doctor's office for rabies vaccinations. Which words would be the most appropriate for a medical student to use in describing the situation?

- reservoir - zoonotic disease

pneumonia is an ________1______ infection that appears quickly and is _____2____ resolved. Occasionally, pneumonia is a ____3____ infection with an initial infection site in the lungs. From the lungs, ______4_____ travel to another area. From there, the infection travels through the bloodstream, causing the infection to become a ______5_____ infection.

1. acute 2. rapidly 3. focal 4. organisms 5. disseminated

the eukaryotes, bacteria, and archaea that live in and on the human body are called normal microbiota. When they were originally discovered, scientists thought that the relationship between these organisms was ______________ because they thought that the organisms _____________ from living on the host but did not help the host. In recent years, researchers have determined that most of our resident microbes derive and give ____________ to the host. This makes the relationship between host and microbe one of ___________. ________, on the other hand, are microbes that cause __________.

1. commensalism 2. benefited 3. benefit 4. mutualism 5. Pathogens 6. disease

epidemiologists study the movement of diseases in a population. They describe ______1_____ diseases that are constantly in a(n) ____2_____. These diseases are generally seen at a ___3____ rate. When several cases appear over a short time, a(n) ___4_____ is declared; if it spreads and affects people through the ____5_____, it's called a _____6______.

1. endemic 2. community 3. low 4. epidemic 5. world 6. pandemic

Many different host factors can influence a person's susceptibility or resistance to infectious disease. Some factors are associated with increased susceptibility, whereas other factors are associated with decreased susceptibility. Organize the following factors, indicating those that increase and those that decrease host susceptibility to infectious disease.

Increase: - smoking & alcoholism - being very young or very old Decrease: - proper nutrition - good hygiene

infection in which symptoms develop rapidly

acute infection

Any microbe that is capable of causing disease in a human host has the same initial encounters with the host's system. Place these events in order, starting with the first contact between host and microbe.

attachment, immune avoidance, obtaining nutrients

infection in which symptom develop slowly and are resolved over months

chronic infection

transmission of disease through direct interaction between two people

direct contact

condition where the human host has been damaged

disease

Insects like fleas and lice that both harm a host and benefit from living on a host are described as ___________ .

ectoparasites

How do scientists describe a disease that is always present in a community?

endemic

Properly cooking food will often break the _______ cycle of disease transmission.

fecal-oral

Over the past 50 years, many researchers and farmers have been selectively breeding cattle to be more resistant to diseases. Based on your knowledge of host-pathogen interactions, animals that are more resistant to disease have __________.

fewer adhesin receptors

Salmonella enterica serovar Typhimurium has a very low LD50 in mice but is generally not lethal in humans. Salmonella enterica serovar Typhi causes typhoid fever in humans and has a very low LD50 in humans, but it doesn't kill mice. This phenomenon can be explained by the fact that the two serovars have different ___________.

host ranges

Which of the following terms describes an infection caused by exposure to medical care?

iatrogenic

When a host's white blood cells attack infecting pathogens, they will often damage nearby tissues and cause symptoms. What do physicians and researchers call the process that causes this damage?

immunopathogenesis

Often the signs and symptoms of an infectious disease, including some sequelae, are caused by the host's immune system killing microbes and nearby host tissues in an array of consequences called __________ (the answer is a single term).

immunopathology

the entry and growth of an organism in and on a host

infection

If a person has had chicken pox in the past, his or her immune system will remove most of the virus. However, a few viral particles will invade nervous tissue, where they will remain hidden for years. If the person is stressed, host-pathogen interaction can become imbalanced, and shingles will develop in skin that is in contact with the infected nerves. This is a classic example of a(n) _________ infection.

latent

infection that persists after an acute illness; organisms are present, but disease is not

latent infection

Normal microbiota live in or on a host and both benefit from their host and provide benefits to that host. How would biologists describe this relationship?

mutualism

pathogen entering a host body by bite or injection

parental route

an organism's ability to cause disease

pathogenicity

animal, plant, or environment that can harbor a pathogen

reservoir

Influenza is a deadly disease because the damage influenza causes in lungs predisposes patients to developing other infections, such as bacterial pneumonia. We describe the bacterial pneumonia as a(n) __________ infection.

secondary infection

When there is an outbreak of an infectious disease, such as SARS or Ebola virus, airports will often screen potential passengers and not allow individuals with a fever to board an international flight. They are looking for ___________ of infection.

signs

True or false: For any organism, the infectious dose 50% (ID50) is ALWAYS lower than the lethal dose 50% (LD50).

true

Which of the following terms describes a living carrier of an infectious organism.

vector

a living carrier of a pathogen

vector

inanimate source of infection

vehicle

measure of the severity of a disease caused by a pathogen

virulence