MB Interactions between Microbes and Humans

What are Reservoirs?

• Reservoirs are man-made structures used for storing oil.

• Primary habitat in the natural world from which a pathogen originates

• Reservoirs are natural lakes formed by volcanic activity.

  
  

• Reservoirs are underground caves filled with water.

Reservoir are primary habitat in the natural world from which a pathogen originates. What are the living reservoirs?

• Humans: ill patients or carrier

• Humans: only ill patients

• Animals

• soil, water, and plants

Reservoir are primary habitat in the natural world from which a pathogen originates. What are the nonliving reservoirs?

• Humans: ill patients or carrier

• Humans: only ill patients

• Animals

• soil, water, and plants

A person suffering from a cold contaminates a pen, which is then picked up by a healthy person. That is indirect transmission. Alternatively, a sick person can transmit the pathogen directly by sneezing on a healthy person. This is an example of which type of reservoir?

• humans: actively ill

• humans: carriers

• animals

• soil, water, and plants

A person who is fully recovered from his hepatitis but is still shedding hepatitis A virus in his feces may use suboptimal hand-washing technique. He contaminates food, which a healthy person ingests (indirect transmission). Carriers can also transmit through direct means, as when an incubating carrier of HIV, who does not know she is infected, transmits the virus through sexual contact. This is an example of which type of reservoir?

• humans: actively ill

• humans: carriers

• animals

• soil, water, and plants

Some pathogens, such as the TB bacterium, can survive for long periods in this reservoirs. They are then directly transmitted to humans when they come in contact with the contaminated reservoir. This is an example of which type of reservoir?

• humans: actively ill

• humans: carriers

• animals

• soil, water, and plants

Answer explanation

• Microorganisms have adapted to nearly every habitat in the biosphere:

• Thrive in soil, water, air

• Surfaces in homes, offices, and other structures in the “built environment”

• Most are saprobic and cause little harm and considerable benefit

• Some are opportunists

• A few are regular pathogens

• Because humans are in regular contact with environmental sources, acquisition of pathogens from nonliving reservoirs is always a possibility

Which of the following describes Asymptomatic carriers?

• Infected but show no symptoms of disease

  
  

• Spread the infectious agent during the incubation period

• Recuperating patients without symptoms; they continue to shed viable microbes and convey the infection to other

• Individuals who shelter the infectious agent for a long period after recovery because of the latency of the infectious agent

• Medical and dental personnel who must constantly handle patient materials that are heavily contaminated with patient secretions and blood risk picking up pathogens mechanically and accidentally transferring them to other patients

Answer explanation

ex Gonorrhea, genital herpes with no lesions, human papillomavirus

Which of the following describes Incubating carriers?

• Infected but show no symptoms of disease

  
  

• Spread the infectious agent during the incubation period

• Recuperating patients without symptoms; they continue to shed viable microbes and convey the infection to other

• Individuals who shelter the infectious agent for a long period after recovery because of the latency of the infectious agent

• Medical and dental personnel who must constantly handle patient materials that are heavily contaminated with patient secretions and blood risk picking up pathogens mechanically and accidentally transferring them to other patients

Answer explanation

ex Infectious mononucleosis

Which of the following describes Convalescent carriers?

• Infected but show no symptoms of disease

  
  

• Spread the infectious agent during the incubation period

• Recuperating patients without symptoms; they continue to shed viable microbes and convey the infection to other

• Individuals who shelter the infectious agent for a long period after recovery because of the latency of the infectious agent

• Medical and dental personnel who must constantly handle patient materials that are heavily contaminated with patient secretions and blood risk picking up pathogens mechanically and accidentally transferring them to other patients

Answer explanation

ex Hepatitis A

Which of the following describes Chronic carriers?

• Infected but show no symptoms of disease

  
  

• Spread the infectious agent during the incubation period

• Recuperating patients without symptoms; they continue to shed viable microbes and convey the infection to other

• Individuals who shelter the infectious agent for a long period after recovery because of the latency of the infectious agent

• Medical and dental personnel who must constantly handle patient materials that are heavily contaminated with patient secretions and blood risk picking up pathogens mechanically and accidentally transferring them to other patients

Answer explanation

ex Tuberculosis, typhoid fever