Respuesta :
Immunological memory accounts for the ancient observation that someone who had recovered from the plague could safely care for those newly diseased.
Significance of plague disease
The plague is a contagious sickness that affects both animals and people. Bacteria named Yersinia pestis causes it.
- This bacteria is prevalent in rats and their fleas around the world, including in the United States.
Sunlight and drying are both effective in killing Y. pestis.
- Even yet, when discharged into the air, the bacteria may live for up to an hour, however, this might vary depending on the environment.
- Pneumonic plague is one of several types of plague. These types may occur independently or in combination, depending on the circumstances:
- When Yersinia pestis attacks the lungs, it causes pneumonic plague. This disease can spread from person to person via the air.
Transmission can occur if a person breathes in aerosolized germs, as could occur in a bioterrorist strike.
- Pneumonic plague can also be disseminated by inhaling Y. pestis suspended in respiratory droplets from a person (or animal) infected with the disease.
- In order to become infected in this manner, you must generally come into direct and personal touch with the sick person or animal.
- If a person with bubonic or septicemic plague goes untreated, the germs can migrate to the lungs and cause pneumonic plague.
The most frequent type of plague is bubonic plague.
- This happens when an infected flea bites someone or when materials contaminated with Y. pestis enter through a skin breach.
- Patients have enlarged, sensitive lymph nodes (known as buboes), as well as fever, headache, chills, and weakness.
Hence, the correct answer is option D
Learn more about plague here,
https://brainly.com/question/23399204
# SPJ4