Microbial Diseases in Humans:
1. Bacterial Diseases:
o Causative Agents: Bacterial diseases are caused by various bacteria. Some common
examples include:
Salmonella: Causes food poisoning and is transmitted through contaminated
food and water.
Streptococcus pyogenes: Responsible for strep throat and skin infections.
Escherichia coli (E. coli): Associated with gastrointestinal infections.
Mycobacterium tuberculosis: Causes tuberculosis (TB).
o Mode of Transmission: Bacteria can be transmitted through direct contact (e.g.,
person-to-person), contaminated food and water, or even via sexual contact1.
2. Viral Diseases:
o Causative Agents: Viruses cause a wide range of diseases. Examples include:
Influenza virus: Causes the flu.
Human immunodeficiency virus (HIV): Responsible for AIDS.
Herpes simplex virus: Causes cold sores and genital herpes.
o Mode of Transmission: Viruses can spread through respiratory droplets, blood,
sexual contact, or contaminated surfaces.
3. Fungal Diseases:
o Causative Agents: Fungi cause fungal infections. Examples include:
Candida albicans: Causes yeast infections.
Trichophyton: Responsible for ringworm.
o Mode of Transmission: Fungi can be transmitted through direct contact,
contaminated soil, or contaminated objects.
Microbial Diseases in Animals:
1. Zoonotic Diseases:
o These are diseases that can be transmitted from animals to humans. Examples
include:
Rabies: Transmitted through bites from infected animals (usually dogs or
bats).
Anthrax: Can be transmitted from livestock to humans.
Avian influenza (bird flu): Spreads from birds to humans.
o Mode of Transmission: Contact with infected animals, their secretions, or
contaminated environments.
Microbial Diseases in Plants:
1. Plant Pathogens:
o Causative Agents: Plant diseases are caused by various pathogens, including:
Fungi: Responsible for diseases like powdery mildew and rust.
Bacteria: Cause diseases like fire blight in fruit trees.
Viruses: Lead to diseases like mosaic virus in tobacco plants.
o Mode of Transmission: Plant pathogens can spread through contaminated soil,
seeds, or insect vectors.
