List Two Ways That Bacteria Can Be Harmful?


2 Answers

Oscar De La Huerte Profile
Bacteria are a form of living organism that are present in every possible environment in the world: From the depths of the ocean to the highest clouds, you'll be able to find bacteria.

Luckily, 99% of the bacteria on earth have no negative impact on human health. Despite this, there is that pesky 1% that can cause illness, and even cause death in humans.

Harmful bacteria

Harmful bacteria are known as pathogens. This type of bacteria is responsible for a number of human illnesses including:

  • Syphilis
  • Anthrax
  • Cholera
  • Tetanus
  • Pneumonia
  • Typhoid fever
One of the most common type of pathogen is the Streptococcus bacteria which is responsible for Strep-throat.

Bacteria in food-poisoning

Food-poisoning is another example of how bacteria can be harmful to human health. Bacteria that enters the body through the mouth (and on food) is one of the leading causes of bacteria-related illnesses.

There are two ways which food-borne bacteria can affect us. The first is through direct contact with the bacteria (this is the case with pathogens such as Salmonella), and the second is through the exotoxins that are excreted by bacteria (for example with Bacillius cereus genreally found on rice).

The most effective method we currently have of controlling the level of bacteria in our food is through temperature control. 

Cooking food to 72 degrees Celsius will effectively kill all bacteria. Freezing food to below -18 degrees Celsius renders all bacteria dormant, and storing food below 5 degrees Celsius slows down bacteria growth significantly (thus prolonging the life of food).

The most harmful bacteria

Whilst there are a number of bacteria-related conditions that are truly terrible, it is hard to think of one that has inspired as much fear and left its mark on human history in the same way as the Yersinia pestis bacteria.

This bacteria was responsible for the epidemic known as the 'Black Plague' or the 'Black Death' and resulted in the deaths of up to 100 million people during the 14th century. It is thought that anywhere between 30-60% of Europe's population perished as a result of this bacteria.
William Harkin Profile
William Harkin answered
If harmful bacteria get into scrapes or cuts sepsis can set in. Some animals leave bacteria on the ground, and if digested can lead to death.

Answer Question