Microorganisms are tiny entities that are invisible to naked eyes and hence are microscopic. They are omnipresent, surviving in extreme climatic conditions. Other than hereditary and genetic factors, almost all other diseases are caused due to the action of microorganisms. Microorganisms are pathogens that carry the disease-causing agents and transmit diseases from one person to another through various media. They are inherently adapted and born with the innate ability to multiply within the host cells.
They are known to cause deadly diseases which in most cases are irreversible and stay for life, disabling infected individuals from carrying out normal functionality daily. Some of the diseases caused by microorganisms are listed below:
- HIV/AIDS
- Typhoid
- Cholera
- Meningitis
- Syphilis
- Chicken Pox
- Malaria
- Tuberculosis
- Ebola
- Influenza
- Bacterial Pneumonia to name a few
Few microbes require a vector to be able to transmit diseases. For instance, mosquitoes carrying Dengue transmit the disease to the host. The pathogen enters into the bloodstream and disrupts normal functioning, furthermore, causes a sudden drop in blood pressure which could be fatal.
Microbes enter the body via contaminated air, water, food or even a small wound on your skin. The Streptococcus bacteria usually enters through an open wound causing infection of the throat etc. In some cases, the bacteria can advance to the flesh and tissues of the host and hence are called flesh-eating bacteria.
Pathogenic diseases are infectious and can be communicated to other hosts in most cases. Upon entry into the body of the host, they use up the nutrients of the host and invade their immune system. As remedial measures, many vaccines and antibiotics are developed as a result.
See Also: Diseases Communicable Non-Communicable
Microbes such as fungi are known to cause plant diseases and various other skin diseases such as ringworm, Tinea corporis. Some diseases can be communicated from animals to humans such as rabies, Q fever. This disease of the plants and animals cause a reduction in the yield of crop production and loss of wildlife. Microbes enter the body through the food we eat and cause food poisoning by releasing toxic substances in the system, to avoid this, food is preserved in several ways(heating, pasteurizing etc).
Classification Of Microorganisms
Harmful microorganisms can be grouped based on how they cause harm.
- Pathogens or disease-causing microorganisms is the first category which can further be sub-divided into pathogens that have the potential to attack humans directly( Vibriocholerae, Mycobacterium tuberculosis) and the second sub-group is the zoonotic microbes, which are the entities such as animals or insects that carry pathogens (Malaria carried by mosquito Anopheles and Rabies by infected dog bite)
- The opportunistic pathogens form the second category. These pathogens can affect humans only if a person falls sick due to a chronic disease, a cut, bleeding, immuno-compromised patients etc.(Example – Pseudomonas aeruginosa)
- The third category of pathogens attacks indirectly by secretion of toxic substances causing harmful effects to humans. ( Example – Clostridium tetani)
Microorganisms can also be classified as fungi, bacteria, viruses, protozoa etc.
Not all microbes are harmful, some are very beneficial to humankind. Few precautionary measures need to be administered against harmful microbes by monitoring and controlling microbial activity.
Questions For You
Q.1. Can you list two plant diseases caused by fungi?
A.1. Downy mildew caused by the entities of phylum Oomycota, Blister rust caused by the genus Cronartium
Q.2. Can you think of any two antibiotic-resistant bacteria?
A.2. Staphylococcus aureus, Burkholderia cepacia
Explore more about microbes and related topics by registering at BYJU’S.
Check out the video given below to know more about microorganisms
Further Reading
- What are the 4 types of diseases?
- Why Apple and cashew are not called true fruits?
- Can microorganisms be harmful?
