Introduction
Ebola and Marburg viruses are considered among the deadliest viruses that can attack humans. These viruses are associated with the rapid deterioration of health and high mortality rates. The current treatment options for the viruses are ineffective and preventing the spread of these viruses during an outbreak remains to be the most efficient technique. This paper will describe the Ebola and Marburg viruses and highlight the transmission methods. It will then describe the symptoms of infection and the treatment options for infected individuals.
Description of the Disease
Ebola hemorrhagic fever and Marburg hemorrhagic fever are two rare viral diseases that are clinically similar. The two diseases are caused by the Ebola virus and the Marburg virus respectively. These two viruses are of the Filoviridae family and their major feature is their distinctive thread-like structure. Leroy, Gonzalez and Baize (2011) define Ebola and Marburg viruses as “a group of viruses characterized by a linear, non-segmented, single-strand negative RNA genome” (p.964). Ebola and Marburg viruses occur naturally in animals and they do not persist in human populations except during the course of an outbreak. These viruses are mostly found in fruit bats and both viruses are primarily confined to sub-Saharan Africa.
The first filovirus outbreak occurred in 1967 in the German regions of Marburg and Frankfurt, and Belgrade city in Yugoslavia (Brauburger, Hume, Mühlberger, & Olejnik, 2012). This previously unknown virus was named the Marburg virus and subsequently classified as a member of the Filoviridae family. The Ebola virus was first recognized in 1976 after an outbreak in Sudan and the DRC. MacNeil and Rollin (2012) note that in spite of the overall rarity of their occurrence, the two diseases are widely recognized due to the largely sensationalist accounts of outbreaks by the mass media.
In spite of the rarity of their occurrence, the Ebola virus and Marburg ARV are highly pathogenic. The two diseases are associated with high fatality rates that may reach up to 90% of the infected population (White & Schornberg, 2012). The high morbidity and mortality rate of Ebola and Marburg viruses has led to the two being classified among the deadliest pathogens. MacNeil and Rollin (2012) document that the devastating nature of Ebola and Marburg virus outbreaks makes them ideal candidates for bioweapons agents.
Significant research has been carried out on these viruses over the past decade. Western governments have offered extensive funding to increase understanding of the biology of these viruses and attempt to come up with a cure. While tremendous progress has been made in understanding the nature of the Ebola and Marburg viruses, there is little progress in identifying effective therapeutics. Research into the pathogenesis of Ebola and Marburg is greatly impeded by the lack of sufficient data on the disease. Most of the outbreaks take place in remote African regions that are not only difficult to access but also lack modern medical equipment that can be used for clinical monitoring and management of the disease. Gene et al. (2009) note that due to the lack of sufficient data, the majority of the currently available data on the disease pathogenesis is performed in animals.
Transmission
Ebola and Marburg are not recognized to be associated with human disease and outbreaks of these diseases occur from the transmission of the viruses from one person to the other. The transmission happens through direct contact with the body, bodily fluids or contaminated clothes of the infected person (MacNeil & Rollin, 2012). Transmission risks from an infected person are greatest when there is a high concentration of the virus in the infected person’s body (Brauburger et al., 2012). The virus concentration is highest during the late stages of the disease making this stage the deadliest for the infected person and people in contact with him/her.
Diagnosis
Ebola and Marburg virus infections have a number of typical symptoms. They include fever, diarrhea, chills, fatigue, headache, and vomiting by the patient. Gene et al. (2009) document that the clinical symptoms appear suddenly after the incubation period, which is between 2 and 21 days. It is difficult to identify the diseases in their early stages since these symptoms are also common in other tropical infections. The Ebola and Marburg symptoms worsen as the disease progresses. Gene et al. (2009) record that there is evidence of multisystem involvement as the disease progresses and the patient will experience nausea, abdominal pain, and this might eventually lead to death. MacNeil and Rollin (2012) observe that in most cases, there is a large lag between initial cases of Ebola virus or Marburg virus infection and actual detection. This contributes to the large outbreaks of the diseases since by the time the diseases are identified and outbreak response measures are taken into place, a large segment of the population has already been infected.
The presence of the Ebola and Marburg viruses is confirmed through laboratory tests. The tests involve antigen detection or the detection of lgM antibodies in the blood (Formenty et al., 2006). Early detection and confirmation of Ebola and Marburg are further hampered by the difficulty in obtaining appropriate clinical samples from individuals suspected of having the diseases. Formenty et al. (2006) note that some patients refuse to provide blood samples to be tested for the presence of the viruses.
Medication and Treatment
At the present, there is no cure for Ebola and Marburg virus infections and treatments seek to treat the symptoms of the infections. Gene et al. (2009) assert that in the absence of licensed vaccines and approved drug therapy to treat filovirus infections, supportive care is the primary means of dealing with patients. Supportive care includes administering drugs to treat the symptoms of the infections. This approach has shown some success in treating Ebola and Marburg infections.
Treatment options also seek to increase the immune response of the patient. This is based on the understanding that filovirus compromises the ability of the patient to produce the T cells required to fight infections (Gene et al. 2009). Patients are therefore provided with the immune-boosting medication. Blood transfusions might also be necessary for the event that a patient has lost significant amounts of blood.
There has been an intense focus on the research and development of a filovirus vaccine. While no vaccine has been licensed yet, significant progress has been made and it is predicted that scientists will soon develop a vaccine for the filoviruses. MacNeil and Rollin (2009) confirm that due to the concentrated focus on the development of vaccines over the past decade, there are numerous promising products in development. However, a cure would be more efficient since it would be unrealistic to successfully vaccinate all people who live in the endemic regions.
Prevention
Considering the high mortality rate of filovirus infection patients, the most effective way of dealing with Ebola and Marburg is to prevent it from occurring. Efforts should be taken to avoid interaction between humans and zoonotic sources of the virus. The introduction of the Marburg virus in humans is associated with people venturing into caves or mines where the carrier bats are found. Programs should be started to advise people against entering caves that might expose them to this virus. Hunting for and processing bush meat can introduce the Ebola virus to a human host (Yokouide et al., 2010). Education outreach programs aimed at discouraging these activities can help limit the introduction of the Ebola virus into human populations.
Preventing virus transmission during outbreaks is integral to containing the diseases (Yokouide et al., 2010). Outbreak response units take into consideration the three distinct contact modalities, which are transmission between family members, contact with dead bodies, and transmission in health care settings. From this knowledge, the response includes close observation of all contact of sic individuals, taking steps to ensure that bodies of deceased individuals are buried safely, and installing infected patients in isolation wards.
Recent Outbreak
Leroy et al. (2011) acknowledge that the disease burden of Ebola and Marburg viruses is extremely small considering that only a few outbreaks resulting in 1671 deaths had occurred by the year 2012. However, in spite of the rarity of filovirus outbreaks, research indicates that they are becoming a prevalent public health problem in sub-Saharan Africa (Yokouide et al., 2010). Over the past decade, there has been an outbreak in the Democratic Republic of Congo and Uganda. The most recent outbreak of the Ebola Virus occurred in the West African countries of Guinea and Liberia. The first case was confirmed in February and by 20 April 2014; the outbreak had spread with over 200 people being infected. The Centers for Disease Control and Prevention (2014) reports that in Guinea, there are 136 confirmed deaths in this ongoing epidemic.
References
Brauburger, K., Hume, A., Mühlberger, E., & Olejnik, J. (2012). Forty-five years of Marburg virus research. Viruses, 4(10), 1878-1927.
Centers for Disease Control and Prevention. (2014). The outbreak of Ebola in Guinea and Liberia. Web.
Formenty, P., Leroy, M., Epelboin, A., Libama, F., Lenzi, M., Sudeck, H., & Yaba, P. (2006). Detection of Ebola Virus in Oral Fluid Specimens during Outbreaks of Ebola Virus Hemorrhagic Fever in the Republic of Congo. Clinical Infectious Diseases, 42(11), 1521-1526.
Gene, O., Biggins, J., Melanson, V., Wahl-Jensen, V., Geisbert, T., & Hensley, L. (2009). Drug targets in infections with Ebola and Marburg viruses. Infectious Disorders Drug Targets, 9(2), 191-200.
Leroy, E., Gonzalez, J-P., & Baize, S. (2011). Ebola and Marburg hemorrhagic fever viruses: major scientific advances, but a relatively minor public health threat for Africa. Clinical Microbiology & Infection, 17(7), 964-976.
MacNeil, A., & Rollin, P. (2012). Ebola and Marburg Hemorrhagic Fevers: Neglected Tropical Diseases? PLoS Neglected Tropical Diseases, 6 (6), 1-7.
White, J., & Schornberg, K. (2012). A new player in the puzzle of filovirus entry. Nature Reviews Microbiology, 10(5), 317-322.
Yokouide, A., Mamadou, K., Formenty, P., Libama, F., Boumandouki, P., Woodfill, C., Sow, I., Duale, S., Alemu, W., & Yada, A. (2010). Lessons learned during active epidemiological surveillance of Ebola and Marburg viral hemorrhagic fever epidemics in Africa. East African Journal of Public Health, 7(1), 32-38.