Ebola hemorrhagic fever, also know as Ebola HF, is not a common disease. However, this disease is severe and often fatal in humans and also primates such as monkeys, gorillas, and chimpanzees. Ever since it’s initial recognition in 1976, there have been four reported sporadic outbreaks in humans around the world. “The first two, in Zaire and in western Sudan, were large outbreaks that resulted in more than 550 cases and 340 deaths. The third outbreak, in Sudan, was smaller, with 34 cases and 22 deaths” (2).
The most recent outbreak was reported only eight years ago in Kikwit, a surrounding area of Bandundu Province, and 316 deaths were reported. In most of these cases the outbreaks were reported in health-care settings, a situation known as amplification, and were caused by poor nursing techniques and usage of unsanitary hospital supplies. This highly infectious disease is caused by the infection by the Ebola virus itself. This Ebola virus, named after a river in the Democratic Republic of the Congo, is one of two members of a family of RNA viruses known as Filoviridae (http://web.uct. ac. za/microbiology/ebola/ebomurph. gif).
Even though the exact origin of the virus is unknown, evidence tells researchers that the virus is animal borne and is usually maintained in an animal host. Evidence also informs researchers that the animal host is native to Africa. Because the origin of the virus is unknown, the carrier state of the virus is also unknown. Therefore the process in which a human is infected with Ebola virus is also undetermined.
An infected human patient can transmit the virus in several ways, by direct contact with blood or bodily secretions of an infected patient, and by contact with objects such as needles used to treat an infected patient. A transfer of the virus from the host to healthy patients is a process known as nosocomial transmission, and occurs frequently through out the period of the outbreak itself. The symptoms of the Ebola hemorrhagic fever are very grotesque and show up soon after the person is infected. Within two to twenty one days, the infected person will have a sudden increase in body temperature, joint and muscle pain, sore throat, weakness, followed by diarrhea, vomiting, and stomach pain.
A rash will then appear, followed by red eyes and internal and external bleeding. Even though the symptoms seem unbearable, some infected patients actually survived this fever. Researchers are unable to explain why some patients live while others die rather quickly. Their hypothesis states, “It is known that patients who die usually have not developed a significant immune response to the virus at the time of their death” (3).
In order for this Ebola hemorrhagic fever to be diagnosed through laboratory tests, the infected patient first has to have all of the above symptoms. It is difficult for researchers to test patients with symptoms such as rash or red eyes because these symptoms are also common with much more frequent illnesses. The VP40-antibodies test has been clinically proven to help with the detection of the Ebola virus. Since diagnostic facilities are limited in Africa, monoclonal antibodies (mAbs) to the Ebola virus were produced from mice that were immune to viral particles.
“Nine stable hybridoma cell lines were obtained producing specific mAbs directed against the viral structure protein, VP40, and these mAbs were characterized by enzyme- linked immunosorbant, immunoblot, and immunofluorescence assays” (4). The enzyme- linked immunosorbent assay detects VP40 of all known species of the Ebola virus, detects viral material in spiked human serum, and also has the ability to become very useful in obtaining accurate diagnosis, at the same time limiting the risk of laboratory infections or outbreaks.
In conclusion, researchers are determining more and more diagnostic tools to help prevent more outbreaks of the Ebola Hemorrhagic Fever. Even though there are still many challenges these researchers have to face in coming up with additional tools to assist in early diagnosis, there are many other tools already in use today. One researcher stated, “One of my goals is to monitor suspected areas to determine the incidence of the disease. More extensive knowledge of the natural reservoir of Ebola virus and how the virus is spread must be acquired to prevent future outbreaks effectively” (3).
1. http://web. uct. ac. za/microbiology/ebola/ebomurph. gif. Access Excellence. 2. http://www. astdhpphe. org/infect/ebola. html. 3. http://www. cdc. gov/ncidod/dvrd/spb/mnpages/dispages/ebola. htm. Ebola Hemorrhagic Fever. Special Pathogens Branch- Diseases: 6 August 2003. 4. Lucht, Andreas, et al. Development, Characterization and use of monoclonal VP40-antibodies for the Detection of Ebola Virus. Journal of Virological Methods: 3 April 2003. 5. Rollin, P. E. , et al. Detection of Ebola-like viruses by Immunofluorcence. Lancet 336, 1591.