Because the natural reservoir (animal or insect host) of the Ebola virus has not been identified, the mechanism by which the virus initially infects a human is unknown. Scientists believe that the hosts are most likely fruit bats. Humans are infected when they come into close contact with the blood, body fluids, secretions, or organs of an infected animal.
Human-to-human transmission occurs in several ways, through direct contact, which occurs through the mucous membranes (eg, the eyes, nose, mouth) or through broken skin (eg, cuts, abrasions). The virus can be transmitted from one human to another through any of these modes of transmission:
- Infected blood, body fluids, or secretions (including but not limited to urine, saliva, sweat, mucous, feces, vomit, semen, and breast milk)
- Infected organs/tissues
- Contaminated objects (eg,needles), surfaces, or materials (eg, bedding, clothing) containing infected blood, fluids, or secretions
