Infection control

Infection control

Infection

The multiplication of pathogenic microorganisms is on the tissues of host which constitute infection.

Invasion and multiplication of pathogens in body tissue and they produce toxin .

Transmissible disease or communicable disease.

Illness resulting from infection.

Source of Infection

1. Endogenous source

2. Exogenous source

1. Endogenous source

Endogenous source lead to endogenous or autoinfection. The source of infection is body's own normal flora as usually non-pathogenic but occassionally that may lead to infection.

For example;

E. Coli (Escherichia coli); a normal flora of intestinal tract may cause urinary tract infection.

Streptococci viridans; a normal flora of mouth may cause infection of endocarditis.

Exogenous source of Infection

1. Human being; cases and carrier

a. Patient b. Carrier

2. Animal

3. Insects 

4. Food

5. Soil and Water

1. Human being

Cases and carrier.

2. Animal (cases and carrier)

Reservoir Host

Many pathogens are capable of causing infection in both human being and animals.

Therefore, animal may act as source of Infection which may acquired by direct contact with animal bite.

Infectious disease transmitted from animals to human directly or indirectly are called "Zoonotic disease".

Viral; Rabies, yellow fever

Bacterial; Salmonella food poisioning, Anthrax

Plague from rats.

Protozoal; toxoplasmosis from cat

Helminthic; Dog tap worm

3. Insects

Disease cause by insects called arthropod borne diseases.

Insect transmitting pathogens are called Vectors.

Blood sucking insects like; mosquito, ticks, mites, flies, live act as source of number of human and animal infection.

For example; 

Typhoid bacilli by domestic fly.

Malaria parasite in Anopheles mosquito.

4. Soil

Important source of infection parasite infection like round worm infection, hook worm infection, fungal infection.

Some pathogens can survive in soil for long period.

Spores of tetanus and gas gangrene serves source of infection.

5. Water

Water contamination with pathogenic microorganism.

Important source of infection like shigellosis (bacillary dysentery).

Water source of infection 

Cholera, polio, Hepatitis A, Hepatitis E, Bacillary dysentery, Typhoid, Amoebiasis, water borne diseases, Diarrhoeal diseases.

Water borne diseases caused by bacteria, virus, parasite, protozoa.

Guinea Wormsin; pond, swimming pool

6. Food

Contaminated food act as source of Infection.

Food borne illness such as;

Food poisioning

Gastroenteritis

Diarrhea

Dysentery (infect intestines inflammation)

Virulence factors

Adhesion

Invasion

Competition for iron and nutrients

Resistance of host community

Secretion of toxin