HSC 4500 Lecture Notes - Lecture 5: Sexually Transmitted Infection, Hiv, Waterborne Diseases
Vehicle-Borne Infections
- Vehicles: contaminated, nonmoving objects
o Can include fomites, unsanitary food, impure water, or infectious bodily fluids.
- Endoscopy: procedure for viewing the inside of a body cavity or organ by using an
instrument such as a flexible tube.
- Fomite: an inanimate object that carries infectious disease agents.
o Ex. Hospital-acquired infections: unsanitary linen contaminated with medical
wastes.
- Foodborne diseases are those caused by ingestion of contaminated food
o Salmonella
- Waterborne infection are those caused by the presence of infectious disease agents that
contaminate the water supply and in which water is the vehicle of infection.
o Ex. Bacterial infections, parasitic infections caused by enteric protozoal parasites,
and viral infections caused by horoviruses.
▪ Enteric protozoal parasites: pathogenic single-celled microorganisms that
can live in the intestinal tract.
Airborne Infections
- Another type of indirect transmission involves the spread of droplet nuclei that are
present in the air.
- May be present in closed and poorly ventilated locations.
Vector-Borne infections
- Vector: an animate, living insect or animal that is involved with the transmission of
disease agents.
o Ex. Arthopods (lice, tics, flies) that bite their victims and feed on the latter’s
blood.
Examples of Significant Infectious Diseases
- Infectious diseases are often grouped into categories that are defined according to the
method by which the disease is spread.
o Sexually transmitted diseases
o Food-borne diseases
o Waterborne diseases
▪ Bacterial conditions
▪ Parasitic diseases
o Vector-borne disease
o Vaccine-preventable diseases
o Zoonotic diseases
o Bioterrorism-related diseases
Sexually Transmitted Diseases
- Sexually transmitted diseases (STDs): infectious diseases and related conditions that can
be spread by sexual contact.
- Human immunodeficiency virus infections
- The term HIV/AIDS covers persons who are infected with HIV but who may not have
been diagnosed with AIDS.
- The infectious agent of HIV is a type of virus called retrovirus.
