Rodents and Vectors
Introduction
Animals can act as source or reservoir hosts of pathogens.
They may harbor pathogens without showing symptoms (asymptomatic).
Diseases transmitted from animals to humans are called zoonoses.
Example:
o Rats (rodents) are the primary reservoir of Yersinia pestis (causes plague)
Vectors
Vectors are animals or insects that transmit pathogens to humans.
Examples of vectors:
o Mosquitoes
o Ticks
o Rodents
o Dogs
o Cats
Rodents
Rodents include:
o Domestic rats
o Wild rats (Rattus rattus)
Commonly found in:
o Sewers
o Drains
o Houses
They spread many human diseases such as:
o Plague
o Typhus
o Typhoid
Types of Vectors
1. Biological Vector
Pathogen develops and multiplies inside the vector.
Example:
o Female Anopheles mosquito → vector of malarial parasite.
2. Mechanical Vector
, Pathogen does not multiply in the vector.
It is carried externally and transferred from one place to another.
Example:
o Housefly carries bacteria from feces or contaminated material to food.
Major Diseases Transmitted by Animals and Vectors
Viral diseases
Rabies
Yellow fever
Japanese encephalitis
Chikungunya fever
Dengue
Rickettsial diseases
Scrub typhus
Murine typhus
Bacterial diseases
Brucellosis
Leptospirosis
Plague
Human salmonellosis
Parasitic diseases
Taeniasis
Hydatid disease
Leishmaniasis
Malaria
Plague
Plague is a zoonotic disease mainly transmitted by rodents and flea vectors.
It is caused by the bacterium Yersinia pestis (earlier called Pasteurella pestis).
The bacteria normally infect rodents.
Sources and Modes of Transmission
Primary host: Rodents (rats, wild rodents).
Vector: Rat flea Xenopsylla cheopis.
Introduction
Animals can act as source or reservoir hosts of pathogens.
They may harbor pathogens without showing symptoms (asymptomatic).
Diseases transmitted from animals to humans are called zoonoses.
Example:
o Rats (rodents) are the primary reservoir of Yersinia pestis (causes plague)
Vectors
Vectors are animals or insects that transmit pathogens to humans.
Examples of vectors:
o Mosquitoes
o Ticks
o Rodents
o Dogs
o Cats
Rodents
Rodents include:
o Domestic rats
o Wild rats (Rattus rattus)
Commonly found in:
o Sewers
o Drains
o Houses
They spread many human diseases such as:
o Plague
o Typhus
o Typhoid
Types of Vectors
1. Biological Vector
Pathogen develops and multiplies inside the vector.
Example:
o Female Anopheles mosquito → vector of malarial parasite.
2. Mechanical Vector
, Pathogen does not multiply in the vector.
It is carried externally and transferred from one place to another.
Example:
o Housefly carries bacteria from feces or contaminated material to food.
Major Diseases Transmitted by Animals and Vectors
Viral diseases
Rabies
Yellow fever
Japanese encephalitis
Chikungunya fever
Dengue
Rickettsial diseases
Scrub typhus
Murine typhus
Bacterial diseases
Brucellosis
Leptospirosis
Plague
Human salmonellosis
Parasitic diseases
Taeniasis
Hydatid disease
Leishmaniasis
Malaria
Plague
Plague is a zoonotic disease mainly transmitted by rodents and flea vectors.
It is caused by the bacterium Yersinia pestis (earlier called Pasteurella pestis).
The bacteria normally infect rodents.
Sources and Modes of Transmission
Primary host: Rodents (rats, wild rodents).
Vector: Rat flea Xenopsylla cheopis.
