Ebola Hemorrhagic Fever: Fact Sheet

How is Ebola virus spread? continued...

Nosocomial transmission has been associated frequently with Ebola HF outbreaks. It includes both types of transmission described above, but it is used to describe the spread of disease in a health-care setting such as a clinic or hospital. In African health-care facilities, patients are often cared for without the use of a mask, gown, or gloves, and exposure to the virus has occurred when health care workers treated individuals with Ebola HF without wearing these types of protective clothing. In addition, when needles or syringes are used, they may not be of the disposable type, or may not have been sterilized, but only rinsed before re-insertion into multi-use vials of medicine. If needles or syringes become contaminated with virus and are then reused, numbers of people can become infected.

Ebola-Reston that appeared in a primate research facility in Virginia, may have been transmitted from monkey to monkey through the air in the facility. While all Ebola virus species have displayed the ability to be spread through airborne particles (aerosols) under research conditions, this type of spread has not been documented among humans in a real-world setting, such as a hospital or household.

What are the symptoms of Ebola hemorrhagic fever?

The signs and symptoms of Ebola HF are not the same for all patients. The table below outlines symptoms of the disease, according to the frequency with which they have been reported in known cases.

Researchers do not understand why some people are able to recover from Ebola HF and others are not. However, it is known that patients who die usually have not developed a significant immune response to the virus at the time of death.

How is Ebola hemorrhagic fever clinically diagnosed?

Diagnosing Ebola HF in an individual who has been infected only a few days is difficult because early symptoms, such as red and itchy eyes and a skin rash, are nonspecific to the virus and are seen in other patients with diseases that occur much more frequently. If a person has the constellation of symptoms described in the table above, and infection with Ebola virus is suspected, several laboratory tests should be done promptly. These include a blood film examination for malaria and a blood culture. If the suspected patient has bloody diarrhea, a stool culture should also be performed.