re a Pu nd of Ap l p a l n i r e d u

o S J c

i

n e

n a

i

c r

e

e

s

g

i N

NJPAS

Ebola Virus Disease – An Emergent Public Health Threat of the Late 20th Century

Dozie, I.N.S.1 , Nwoke, B.E.B. 2 , Amadi, A.N. 1 , Chukwuocha, U.M.1 , Dozie, W.U.1 , Ezelote, J 1 , Lerum, N.I. 3 , Chidebelu, P.E 3 , Enweani, E.O. 3 , Faro, F.O.3 , Nwabueze, I.C. 3 . 1.Department of Public Health Technology, Federal University of Technology Owerri, Owerri. 2.Department of Animal and Environmental Biology, Imo State University Owerri, Nigeria. 3.Department of Microbiology, University of Nigeria Nsukka, Nigeria. Corresponding author: [email protected] Abstract virus disease is one of the new emerged infectious diseases of the late 20th century. It is a severe, often fatal illness in humans marked by severe bleeding (haemorrhage), organ failure and with fatality rates of between 50% and 90%. Ebola virus is native to Africa and is previously characterized by outbreaks in isolated and remote communities in the rainforest. The 2014 Ebola outbreak is reported in four West African countries namely, Guinea, , Sierra Leone and Nigeria. Ebola virus disease (EVD) is caused by members of the genus with five (5) recognized species namely , , Ivory Coast Ebolavirus, Reston Ebolavirus and , all of which belongs to the family, . The transmission of Ebola virus involve two major steps; firstly from suspected natural hosts or reservoir believed to be fruit bats to animals in the wild and secondly, from animals in the wild to humans. Human-to-human transmission occurs through direct contact (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids (vomit, faeces, urine, breast milk, semen and sweat) of infected persons. Although the clinical course of infection with an incubation period of between 2 to 21 days is well known, the specific mechanisms underlying the pathogenicity of Ebola virus have not been clearly understood. Several lines of evidence suggest that the viral glycoprotein (GP) plays a key role in the manifestation of Ebola virus infection. EVD can be diagnosed in the laboratory by reverse transcriptase polymerase chain reaction (RT-PCR) assay, antibody-capture enzyme-linked immunosorbent assay (ELISA), antigen detection tests, serum neutralization tests and virus isolation by cell culture. Currently there are no approved drugs or vaccines to treat or prevent Ebola. Treatment consists of supportive therapy to maintain electrolyte balance. However experimental vaccines and antiviral drugs are undergoing development and clinical trials. The potential treatment of Ebola Haemorrhagic fever patients with passive immune therapy (i.e. blood transfusion) from convalescent patients is being explored. Prevention of EVD consists of avoiding close contact with gravely illness patients, improvement of personal hygiene especially hand hygiene, strict barrier nursing techniques including use of personal protective equipment and safe burial of the dead.

Introduction communicable diseases (NCDs) are more Infectious or communicable diseases are prevalent in the developed economies of essential part of humanity, human civilization Europe and North America where lifestyle and and history. Infectious disease outbreaks genetics are the most prominent predisposing occur from time to time especially in the factors. Examples of NCDs are cancer, developing economies of the world including diabetes, obesity, high blood pressure, Africa where conditions encourage their cardiovascular disorders etc. prevalence and persistence (Dozie et al., An infectious disease is defined as, “an 1999). On the contrary, the non- illness due to a specific infectious agent or its

© Nigerian Journal of Pure and Applied Sciences ISSN: 0795 - 25070 Vol. 6, 2014, pp. 1-10 2 Ebola Virus Disease – An Emergent Public Health Threat of the Late 20th Century toxic product that arises through transmission which is reported to be the worst so far in of that agent or its product from an infected history underscores once again the great person, animal or reservoir to a susceptible importance of rapid travel or transportation in host, either directly or indirectly through an the epidemiology and distribution of intermediate plant or animal host, vector or the infectious diseases (Giesecke, 2002). inanimate environment”. EVD is an example of an infectious disease. , a Belgian and one of the The past forty (40) years have been scientists who discovered Ebola virus admits characterized by the emergence of new being surprised by the magnitude of the infectious diseases of public health current epidemic which is the 25th in the whole significance (Nwoke et al., 2007). Emerging of Africa. According to Piot, “All previous infections account for at least 12% of all epidemics were quite limited in time and human pathogens (Taylor et. al., 2001). place, generally affecting small villages or Emerging infectious diseases are caused by small towns and would die out after classic newly identified species or strains that may isolation and quarantine, but in this case it's have evolved from a known infection or different” spread to a new population or area undergoing ecological transformation (Lashley, 2004; Estimates by the World Health Fauci, 2005). Examples of newly emerged Organization (2014) show that over 3000 diseases are Haemorrhagic Disease people have died from the current Ebola or Marburg Viral Disease (MVD) discovered epidemic within a period of nine (9) months. in 1967 in Germany, Lassa Virus discovered in Whereas in the 38 years of Ebola history since 1969 in Nigeria, Legionnaires' disease its discovery in 1976, a total of 34 outbreaks discovered in US in 1976, Ebola Haemorragic occurred involving 2,432 human cases with Fever (now Ebola Virus Diseases, EBV) 1,563 (64%) deaths. Daily unfolding statistics described in Zaire and Sudan in 1976, shows the seriousness of the current epidemic Acquired Immune Deficiency Syndrome in West Africa and underscores the urgent (AIDS) described in homosexuals in 1981 in need to put in place appropriate measures to USA and Severe Acute Respiratory Syndrome check the spread of the virus. (SARS) described in China in 2002. A number of older and well known Definition, Origin and Timeline of Ebola diseases have also re-emerged with greater Virus Disease public health significance. A typical example Ebola virus disease is simply defined as of a re-emerged disease is drug resistant a severe, often fatal illness in humans marked tuberculosis (TB) (Lashley, 2004; Fauci, by severe bleeding (haemorrhage), organ 2005). The re-emergence of TB is associated failure and in many cases death. EVD with the advent of HIV/AIDS which is outbreaks have case fatality rates of between characterized by severe immunodeficiency. 50% and 90% (i.e. 5 to 9 persons out of 10 These outbreaks are characterized by high infected persons die of the disease) (Peters and mortality and morbidity. They cause much Khan, 1999, Sanchez, et al., 2001, CDC, 2014; pains, suffering, anxiety, panic and impede WHO, 2014). Ebola virus is native to Africa. socio-economic development and Ebola was first discovered in two transformation of nation states. simultaneous outbreaks in Zaire (now called The world once again is witnessing the Democratic Republic of Congo, DRC) and devastating effects of the Ebola virus Sudan (Bowen et al., 1977, Johnson et al., outbreak. The theater of the 2014 outbreak is 1977). The outbreak in Zaire occurred in West Africa. This outbreak originated from August/September 1976 in Yambuku located Guinea and has spread through transportation in the Equater Province in the northwest of to neigbouring countries of Liberia and Sierra Zaire. In the Equater Province is a small Leone and most unfortunately to Nigeria stream located in the forest called the Ebola (WHO, 2014). The current Ebola outbreak River. The disease discovered by Belgian Nigerian Journal of Pure & Applied Sciences Vol. 6, 2014. 3 scientists was named after the river, thus Ebola them. The three most important risk factors disease. The virus was isolated and associated with this outbreak were attending characterized in October, 1976 (Johnson et al., funerals of Ebola patients, contact with 1977). These initial outbreaks were spread by infected family members and provision of care close personal contact and by use of to hospitalized patients without adequate contaminated needles and syringes in personal protective measures. This was hospitals/clinics. Three hundred eighteen followed by outbreaks in Gabon and Zaire in (318) human cases were reported in the Zaire 2001 and 2003 which had case fatality rates of outbreak out of which 280 (88%) died. The between 75% to 89%. In 2004, another Sudan outbreak occurred in Nzara, Maridi and outbreak occurred in Yambio county of south surrounding areas and killed 151 (53%) Sudan and killed 7 (41%) of 17 reported cases. persons out of 284 reported cases. Similarly between 2007 and 2008, a new According to WHO (2014), a single case strain of Ebola virus called the Bundibugyo of Ebola was reported in Zaire in Tandala virus emerged and infected 149 (25%) people village in 1977, and the individual died in Bundibugyo District of western Uganda. In (100%). Furthermore, in 1979, 34 people in 2008, 6 people working in a pig farm Sudan got infected and 22 (65%) were killed. developed antibodies against another strain of The outbreak had occurred in the same areas as Ebola (). In same 2008, DRC the 1976 outbreak namely Nzara, Maridi in (formerly Zaire) witnessed another outbreak Sudan. in the Mweka and Luebo Health zones of In 1994, Ebola outbreak occurred in Kasai Province and killed 15 (47%) out of 32 Mekouka, Gabon, and other gold-mining infected cases. camps located deep in the rainforest. Of the 52 Between 2009 and 2013, there were few people infected, 31 (60%) died of the disease. cases reported in Uganda and DRC. This was a Also in 1994, a scientist who performed an crucial period in Ebola timeline as rapid autopsy on a wild chimpanzee in Ivory Coast diagnostic testing for Ebola was provided by was infected with Ebola virus and survived the new CDC Viral Haemorrhagic Fever after supportive treatment in Switzerland. Laboratory installed at the Uganda Viral In 1995, a major outbreak occurred in Research Institute (UVRI) (WHO, 2014). Kikwit Zaire killing 250 out of 315 infected The 2014 outbreak in West African people. The case fatality rate was 81% which countries is reported to have begun in Guinea was much higher than the original outbreak in in December 2013. The outbreak has spread to 1976. It is reported that the virus spread Liberia, Sierra Leone and Nigeria. WHO through an infected individual working in the declared it the most severe and deadliest Ebola forest areas who passed it on to neigbours, outbreak till date. Ebola outbreak 2014 was family members and healthcare workers. officially notified as a public health Between 1996 and 1997, two Ebola emergency on August 8, 2014. As at end of outbreaks occurred in Gabon. The first September 2014, an estimated 3000 people occurred in Mayibout area and was traced to have died of the epidemic (WHO, 2014). consumption of dead chimpanzee. Nineteen people who were involved in cutting the Classification and Geographical animal become ill and other cases occurred Distribution of Ebola Virus among family members. Of the 37 people Ebola virus disease (EVD) is caused by affected, 21 (57%) died. The second outbreak members of the genus Ebolavirus which occurred in Booue area of Gabon. 45 (74%) belongs to the family, Filoviridae. Filovirus deaths were obtained out of 60 people are pleomorphic, negative-sense RNA viruses infected. whose genome organization is most similar to Between 2000 and 2003, Uganda the Paramyxoviridae. Previously, the genera witnessed the first outbreak in the districts of Ebolavirus and were classified Gulu, Masindi, and Mbarara. The virus as species of the now obsolete Filovirus genus. infected 425 people and killed 224 (53%) of However, in 1998 the International 4 Ebola Virus Disease – An Emergent Public Health Threat of the Late 20th Century

Committee on Taxonomy of Viruses (ICTV) which have led to research towards viral changed the Filo virus genus to Filo viridae shedding in the saliva of bats (Gonzalez et al., family with two specific genera; Ebola-like 2007). It is notable that transmission between viruses and Marburg-like viruses. In 2000, natural reservoirs and humans is rare. another proposal was made to change the “like Ebola is introduced into human virus” to “virus” resulting in the names used population through close contact with the today Ebola virus and blood, secretions, organs or other bodily fluids (Feldman et al., 2004). of infected animals such as chimpanzees, The genus Ebola virus contains five (5) gorillas, monkeys, antelope etc. Human-to- recognized species namely: Zaire Ebola virus, human transmission occurs through direct Sudan Ebola virus, Ivory Coast Ebola virus, contact (through broken skin or mucous Reston Ebola virus and Bundibugyo Ebola membranes) with the blood, secretions, organs virus (Feldman et al., 2004). The patterns of or other bodily fluids (vomit, faeces, urine, outbreak seem to suggest that each filo virus breast milk, semen and sweat) of infected may have a distinct geographical range. For persons. instance, Ivory Coast Ebola virus has been Infection can also occur indirectly if reported only in West Africa, while Sudan broken skin or mucous membrane of a healthy Ebola virus appears to occur in East Africa person comes in contact with environments (Sudan and Uganda). The Zaire Ebola virus is contaminated with an Ebola person's reported mainly from Central African in infectious fluids such as soiled clothing, bed countries like Gabon, Republic of Congo and lining, or used needles. Burial ceremonies in DRC (formerly called Zaire). Bundibugyo which mourners or mortuary attendants have Ebola virus was reported from an outbreak in direct contact with the body of the deceased Uganda. Reston Ebola virus has its origins in person (i.e. corpse) can also play a role in the the Philippines. The Zaire strain is reported to transmission of Ebola virus. Persons who have be the most pathogenic strain (Feldman et al., died of Ebola must be handled using strong 1994; Sanchez et al., 1996). protective clothing and gloves and must be buried immediately. Reservoir of Ebola virus Exchange of body fluids appears to be Very little is known about the natural necessary before infection can occur. It is history of Ebola virus. Several animal notable that transmission among humans is reservoirs and arthropod vectors have been almost exclusively among caregiver family studied without successful identification of members or healthcare workers tending to the the reservoir of infection. However, evidence very ill (CDC, 2014). Many healthcare including the finding of high quantity of Ebola workers have been exposed to the virus while virus in fruit bats without showing overt caring for Ebola patients. This happens illness suggests that they can be reservoir of because they may not have worn personal infection (Swanepoel et al., 1996). protection equipment or were not properly applying infection control measure. Transmission of Ebola virus There is no documented evidence that The transmission of Ebola virus involve the virus can be transmitted by air. Evidence two major steps; firstly from suspected natural from Kikwit, DRC which has the custom of hosts or reservoir (fruit bats) to animals in the children not touching ill adults showed that wild and secondly, from animals in the wild to children who lived in small one room huts with humans. It is believed that terrestrial parents who died from Ebola did not become mammals like gorillas, chimpanzees, duikers, infected (CDC, 2014). This strongly supports antelopes etc get infected when they eat fruits the view that direct contact with sick patients and pulp dropped by fruit bats which are the is a means of transmission while air is not a suspected reservoirs of the virus. This chain of means of transmission. However, the potential events forms a possible means of transmission transmission of Filoviruses as aerosols under from natural host to animal populations, laboratory conditions have resulted in their Nigerian Journal of Pure & Applied Sciences Vol. 6, 2014. 5 classification as Category A biological usually include diffuse bleeding, and weapons (Leffel and Reed, 2004). hypotensive shock accounts for many Ebola virus fatalities (Colebunders & Borchert, Ebola Virus disease progression 2000; Sanchez et al., 2001). Although the clinical course of infection Several lines of evidence suggest that is well known, the specific mechanisms the viral glycoproteins (GP) play a key role in underlying the pathogenicity of Ebola virus the manifestation of Ebola virus infection have not been clearly understood. According (Sullivan et al., 2003). The transmembrane to Sullivan et al., (2003) this is due, partly to form of GP targets the Ebola virus to cells that the difficulty in obtaining samples and are relevant to its pathogenesis. Specifically, studying the disease in the relatively remote GP allows the virus to introduce its contents areas in which outbreaks occur. In addition a into monocytes and/or macrophages, where high degree of biohazard containment is cell damage or exposure to viral particles may required for laboratory studies and clinical cause the release of cytokines (Stroher et al., analysis. Isolation of the viral cDNAs and the 2001) associated with inflammation and fever, development of expressive systems have and into endothelial cells, which damages allowed the study of Ebola virus gene products vascular integrity (Yang et al., 2000). Thus under less restrictive conditions and facilitated sGP may alter the immune response by an understanding of the mechanisms inhibiting neutrophil activation, while the underlying virally induced cell damage. transmembrane GP may contribute to the The incubation period (i.e. from time of haemorrhagic fever symptoms by targeting infection to onset of clinical symptoms) is 2 to virus to cells of the reticuloendothelial 21 days with an average period of 5 to 9 days. network and the lining of blood vessels. Infected people can transmit the virus as long as their blood and secretions contain the virus. Diagnosis People who are gravely ill are highly EVD is clinically indistinguishable from infectious and contact with their blood and other haemorragic fever especially Marburg secretions/bodily fluids result in infections haemorrahgic fever. Furthermore, EVD can be (CDC, 2014). It is notable that infected people confused with many other infectious diseases are NOT CONTAGIOUS until they are prevalent in sub-Saharan Africa such as acutely ill. Only when ill does the viral load malaria, typhoid fever, shigellosis, cholera, express itself first in blood and then in other leptospirosis, plague, relapsing fever, bodily fluids (including vomit, faeces, urine, meningitis, hepatitis (WHO, 2014). Non- breast milk, semen and sweat). infectious conditions that can be confused Infection initially presents nonspecific with EVD include leukemia, hemolytic flu-like symptoms such as fever, myalgia and uremic syndrome, snakeenvenomation, malaise. As infection progresses, patients clotting factor deficiencies/platelet disorders. exhibit severe bleeding and coagulation In the laboratory, EVD can be diagnosed abnormalities, including gastrointestinal by reverse transcriptase polymerase chain bleeding, rash, and a range of hematological reaction (RT-PCR) assay, antibody-capture irregularities, such as lymphopenia and enzyme-linked immunosorbent assay neutrophilia (Sullivan et al., 2003). Cytokines (ELISA), antigen detection tests, serum are released when reticuloendothelial cells neutralization tests and virus isolation by cell encounter virus, which contribute to culture. These tests can be performed in field exaggerated inflammatory response that are or mobile hospitals and laboratories. not protective. Damage to the liver, combined with massive viremia, leads to disseminated Epidemiology intravascular coagulopathy. The virus Ebola is undoubtedly zoonotic i.e. eventually infects microvascular endothelial transmission is from animals to man and the cells and compromises vascular integrity. The disease appears to be more severe in primary terminal stages of Ebola virus infection than secondary cases. Outbreaks of Ebola 6 Ebola Virus Disease – An Emergent Public Health Threat of the Late 20th Century have mainly been restricted to Africa Wyers et al., 1999). It is noteworthy that live (Colebunders and Borchet, 2000). Previous attenuated viruses and recombinant proteins outbreaks have occurred mostly in remote have been used successfully in a variety of locations in the rainforest. Besides quarantine vaccines, but the safety and immunogenicity measures to contain these outbreaks, lack of of gene-based vaccines have proven access roads and poor transportation helped in increasingly attractive (Sullivan et al., 2003). localizing or containing these outbreaks. The However, these investigational products index cases in these outbreaks are usually are in the earliest stages of product people who live in the forest or whose development and have not yet been fully occupations take them to the forest. The tested for safety or effectiveness. Small secondary cases are often family members and amounts of some of these experimental healthcare workers who contracted the products have been manufactured for clinical infection by close personal contact and by use trials. It is the expectation of the US Food and of contaminated needles and syringes. Drug Administration (FDA) that these Nosocomial (i.e. hospital associated investigational products will one day serve to infection) spread is common, particularly improve clinical outcomes for Ebola patients. affecting nurses and doctors (CDC, 2004). The potential treatment of Ebola Transmission by sexual intercourse has been Haemorrhagic fever patients with passive described from one case to his wife, 83 days immune therapy (i.e. blood transfusion) from after initial infection. It is notable that both convalescent patients have been reported males and females and people of all age (Mupapa et al., 1999). Of the 8 patients in categories are equally susceptible to infection. Kikwit, DRC who met Ebola haemorrhagic fever case definition and tansfused with blood Treatment of EVD, Vaccine and Antiviral donated by 5 convalescent patients, only one Therapy Development patient (12.5%) died. This number is Currently there are no approved drugs or significantly lower than the overall case vaccines to treat or prevent Ebola. The US fatality (80%) for Ebola haemorrhagic fever Centre for Disease Control (CDC) epidemic in Kikwit. The reason for this low recommends supportive therapy for patients case fatality remains to be explained. as the primary treatment for Ebola. This includes balancing the patient's fluids and Prevention and Control electrolytes, maintaining their oxygen status The prevention of EVD presents a and blood pressure and treating them for any significant challenge. The ideal thing would complicating infections. The hallmark of be to eliminate the suspected reservoir of treatment of Ebola is supportive care and infection (i.e. fruit bats). Also the rapid rigorous infection control (CDC, 2014; WHO, progression of Ebola virus infection has 2014). further complicated the control of this disease, It is noteworthy that there are affording little opportunity to develop experimental Ebola vaccines and antiviral acquired immunity. What is fundamental in therapy under development. This is due to an prevention is to understand the nature of the understanding of the mechanisms underlying disease, how it is transmitted and how to Ebola virus-induced cytopathic effects. prevent it from spreading further. Several animal models have been developed While initial cases of EVD are to study the pathogenesis of Ebola virus contracted by handling infected animals or infection and to assess the efficacy of various carcasses, individuals should reduce contact vaccine approaches. Guinea pigs and with high-risk animals (i.e. fruit bats, nonhuman primates represent the primary monkeys, apes, gorillas, antelopes etc). animal models for vaccine development Animal products (blood and meat) including because the progression and pathogenesis bush meat must be thoroughly cooked before most closely resemble those of the human consumption. disease (Xu et al., 1998, Connolly et al., 1999, Close physical contact with Ebola Nigerian Journal of Pure & Applied Sciences Vol. 6, 2014. 7 patients should be avoided. Appropriate cremation which is the application of high personal protective equipment (PPE) temperature to reduce bodies to basic including gloves, impermeable gowns, chemical components (ashes) is ideal for safe boots/covered shoes, masks and goggles (to disposal of bodies of persons or animals who protect against splashes) must be worn when die during outbreaks of highly infectious taking care of ill patients at home or in the diseases such as Ebola virus. This is to hospital (WHO, 2014). Strict infection- minimize further transmission. It is notable control measures must be applied including that in 2013 the State Government regular hand washing with soap especially introduced its Voluntary Cremation Law after visiting patients in hospital, or after under which a person may signify interest to taking care of patients at home and be cremated at death or a deceased's family sterilization of equipment used in member who must attain the age of 18 years hospitals/clinics. Suspected cases should be can decide to have the corpse cremated. reported immediately to health authorities for It is noteworthy too that the virus is immediate quarantine while confirmed cases easily killed by heating at 600 C for 30 minutes, should be isolated. It is recommended that ultraviolet (UV) and gamma radiation, isolated persons should be kept alone in single formalin (1%), lipid solvents, hypochlorite or isolation rooms. Access to these areas should phenolic disinfectants and bleach. It is be restricted and equipment for treatment believed that exposure to sunlight, contact dedicated to isolated patients. Occasionally with soap as well as use of washing machine access may be given to individuals who are even for clothing saturated with infected body necessary for the patient's wellbeing and care, fluids will kill virus. such as a child's parent. WHO advises families or communities Ebola Virus Disease (EVB) in Nigeria- not to care for individuals who may present Current Status with symptoms of Ebola virus disease in their It is now history that Nigeria is homes. Such families or communities should witnessing her first Ebola disease outbreak. seek treatment in a hospital or treatment center The disease was imported into Nigeria by staffed by doctors and nurses qualified and Patrick Sawyer, a Liberian-American who equipped to treat Ebola victims. If they chose flew into the country on July 20, 2014. He was otherwise, WHO strongly advises them to treated at the First Consultant Medical Center, notify local public health authorities and Lagos where he died and infected the doctors receive appropriate training, equipment and nurses who cared for him. The cities (gloves and personal protective equipment, currently affected by EVD or its scare are PPE) for treatment, instructions on proper Lagos, Port Harcourt and Enugu. removal and disposal of PPE, and information Statistics by the Federal Ministry of on how to prevent further infection and Health show that the total number of Ebola transmission of disease to oneself, other Virus Disease cases so far reported in Nigeria family members, or the community. Hospitals is nineteen (19). The number of deaths is seven and other health facilities that have hosted (7), while the number of those successfully Ebola cases should be decontaminated managed and discharged stand at twelve (12). periodically. Decontamination should include It is noteworthy that all 19 cases include the surfaces and equipment and management of index case (Patrick Sawyer), the primary soiled linen and of waste (WHO, 2014). contacts of the index case who are mostly Furthermore, people who died of Ebola medical personnel and the secondary contacts should be promptly and safely buried. It is who are mainly spouses of the primary recommended that the deceased be handled contacts. It is significant that all cases under and buried by trained case management surveillance in Nigeria especially in the cities professionals (such as environmental health of Lagos, Port Harcourt and Enugu have all officers) who are equipped to properly bury been released following completion of the 21- the dead. Furthermore, it is recommended that day incubation period and non developed 8 Ebola Virus Disease – An Emergent Public Health Threat of the Late 20th Century active disease. 2014 outbreak was inability of affected local Notwithstanding this cheering communities to respond quickly with barrier development, the Federal Government is nursing techniques and strict infection control working relentlessly with all stakeholders, measures since the clinics in these local particularly the World Health Organization settings maybe ill-equipped to manage such and the Lagos State Government to maintain outbreaks. surveillance and strengthen containment Fifthly, the level of awareness about the activities by setting up isolation and treatment importance of hygiene, especially hand wards as well as the public enlightenment hygiene and environmental sanitation is very campaigns. high even among the local and uneducated people in villages and communities. Challenges about EVD Prevention and Optimism for Containment/Control Proactive Measures against EVD Many challenges exist about EVD. One Some proactive measures in the of these challenges include circulating false containment of EVD will include sustained information about prevention of EVD. In massive enlightenment campaign including Nigeria for instance, it is widely rumoured that staying informed as an individual and keep eating bitter kola or drinking salt water or others informed too. The degree of panic bathing with salt can prevent Ebola disease. occasioned by the epidemic can be stemmed Indeed, undocumented reports showed that down with adequate information about EVD. many people drank salt water or bathed with Necessary precautionary measures should be salt water or ate bitter cola as a preventive taken by reporting suspected cases for strategy. It is known that such practices such as quarantine, isolation and treatment. drinking salt water can aggravate a diseased Unnecessary travels especially to countries condition as hypertension. currently experiencing outbreaks must be Like every epidemic, scientists are avoided. It is absolutely important to wash optimistic that the 2014 EVD outbreak will be hands regularly with soap and water or use of contained. This is especially now that affected hand sanitizers. Information must be made governments and indeed the international available to everyone, since everybody is community have adopted proactive measures susceptible to infection with virus. Where ever towards its containment such as massive the virus is present, it represents danger to all. enlightenment campaigns, setting up of The directives issued the Ministry of Health or isolation centers for treatment of the sick and any other agency involved in keeping updates quarantine of suspected cases for strict on EVD must be adhered to. observation etc. Secondly, the pattern of infection World Health Organization (WHO) and especially means of transmission is fairly Response to EVB known to put in place appropriate preventive WHO provides technical advice to measures. Of significance is the fact that, there countries and communities to prepare and is no evidence that the virus can be transmitted respond to Ebola outbreaks such as: disease by air (i.e. it is not an air-borne infection) surveillance and information sharing across (CDC, 2014). regions, technical assistance to investigate and Thirdly, the infective virus as a natural contain outbreaks, advice on prevention and agent will continue to lose its power of treatment options, deployment of experts and pathogenicity (i.e. attenuation) as it is distribution of health supplies (such as transmitted from one person to another. This is personal protection equipment) to countries partly the reason index cases have more severe upon request, communications to raise infections than primary and secondary awareness of the nature of the disease and contacts. protective health measures to control Fourthly, a major suspected factor that transmission of the virus, activation of resulted in quick spread of the virus in the regional and global networks of experts to Nigerian Journal of Pure & Applied Sciences Vol. 6, 2014. 9 provide technical assistance, if requested and Dozie, I.N.S., Iwuagwu, F.O., Nwoke, B.E.B. mitigate potential international health effects (1999). HIV/AIDS epidemic and its and disruptions of travel and trade. speculated African origin: A re- appraisal. Negro Educ. Rev. L (3-4): 79- Conclusion 87. West Africa is experiencing her first Ebola virus disease outbreak on a devastating Fauci, A.S. (2005). "Emerging and scale. The fatality rate within a period of 8 reemerging infectious diseases: the months of the outbreak is over 50% which is perpetual challenge". Academic quite significant and underscores the Medicine 80 (12): 1079–85. declaration of the outbreak as a Public Health Emergency by the World Health Organization. Feldman, H., Nichol, S.T., Klenk, H.D., The Nigeria Ebola disease was imported into Peters, C.J., and Sanchez, A. (1994). the country on July 20, 2014 by the Liberian- Characterization of filoviruses based on American, Patrick Sawyer. The death toll is 7 differences in structure and antigenicity out of 19 confirmed cases giving an ofn the virion glycoprotein. Virology, approximate case fatality rate of 37%. The 199: 469-473. modes of transmission are fairly well known to implement effective preventive measures. It Feldman, H., Geisbert, T.W., Jahrling, P.B., is notable that the Federal Government of Klenk, H.D., Netesov, S.V., Peters, C.J., Nigeria and international agencies and Sanchez, A., Swanepoel, R., and governments are sparing no efforts to contain Volchkov, V.E. (2004). In Virus the disease in West Africa. In the absence of an Taxonomy. Viiith Report of the approved antiviral drug for treatment and International Committee on Taxonomy vaccine for prevention, the sustenance of of Virus, pp 645-653. preventive information on EVD and education Elsevier/Academic Press, London. of the citizenry remains key to the control of EVD in West Africa. Giesecke, J. (2002). Modern Infective Disease Epidemiology. Arnold publications, References London. Bowen, E.T., Lloyd. D., Harris, W.J., Platt, G.S., Baskerville, A., and Vella, E.E. Gonzalez, J.P., Pourrut, X., Leroy, E. (2007). (1977). Viral haemorrhagic fever in Ebolavirus and other filoviruses. Curr. southern Sudan and northern Zaire. Top. Microbiol. Immunol. 315: 363-387. Preliminary studies on the etiological agent. Lancet : 571-573 Johnson, K.M., Lange, J.V., Webb, P.A., and Murphy F.A. (1977). Isolation and CDC (2014). Ebola Haemorrhagic Fever: partial characterization of a new virus Chronology of Ebola Haemorrahagic causing acute haemorrhagic fever in fever outbreaks. CDC Fact Sheet. Zaire, Lancet : 569-571. (Unpublished). Colebunders, R., and Borchert, M. (2000). Lashley, F.R. (2004). Emerging infectious Ebola haemorrhagic fever – a review. J. diseases: vulnerabilities, contributing Infect. 40: 16-20. factors and approaches. Expt. Rev. Anti- infect. Ther. 2(2): 299-316. Connolly, B.M., Steele, K.E., Davis, K.J., Geisbert, T.W., Kell, W.M., Jaax, N.K. Leffel, E.R. and Reed, D.S. (2004). Marburg and Jahrling, P.B. (1999). Pathogenesis and Ebola viruses as aerosol threats. of experimental Ebola virus infection in Biosecurity and Bioterrorism: guinea pigs. J. Infect. Dis. 179: S203- Biodefense strategy, Practice and S217. Science, 2(3): 186-191. 10 Ebola Virus Disease – An Emergent Public Health Threat of the Late 20th Century

Mupapa, K., Massamba, M., Kibadi, K., Stroher, U., West, E., Bugany, H., Klenk, Kuvula, K., Bwaka, A., Kipasa, M., and H.D., Schittler, J., and Feldman, H. Colebunders, B. (1999). Treatment of (2001). Infection and activation of Ebola Haemorrahgic fever with blood monocytes by Marburg and Ebola transfusions from convalescent patients. viruses. J. Virol. 75: 11025-11033. J. Infect. Dis. 179 (supplement 1): S18- S23. Sullivan, N., Yang, z., and Nabel, G.J. (2003). Ebola virus pathogenesis: implications Nwoke, B.E.B.; Nwoke, E.A.; Ukaga, C.N.; for vaccines and therapies. J. Virol. 77 Anosike, J.C.; Dozie, I.N.S.; Ajero, (18): 9733-9737. C.M.U. The impact of changing human environment and climate change on Swanepoel, R.L., Leman, P.A., Burt, F.J., emerging and re-emerging parasitic Zachariades, N.A., Braack, L.E., diseases. Nig. J. Parasitol. 28 (2): 135- Ksiazek, T.G., Rollin, P.E., Zaki, S.R. 145 (2007). and Peters, C.J. (1996). Experimental inoculation of plants and animals with Peters, C.J. and Khan, A.S. (1999). Filovirus Ebola virus. Emerg. Infect. Dis. 2(4): diseases. Curr. Top. Microbiol. 321-325. Immunol. 235: 85-95. Taylor, L. (2001). Risk factors for human Sanchez, A., Trappier, S.G., Mahy, BW.J., disease emergence Phil. Trans. Roy. Peters, C.J. and Nichol, S.T. (1996). The Soc. B, 356(1411):983-9. virion glycoproteins of Ebola viruses are encoded in two reading frames and are Wyers, M., Formenty, P., Cherel, Y., Guigand, expressed through transcriptional L., Fernandez, B., Boesch, C., and Le editing. Proc. Natl. Acad. Sci. USA 93: Guenno B. (1999). Histopathological 3602-3607. and immunohistochemical studies of lesions associated with Ebola virus in a Sanchez, A., Ksiazek, T.G., Rollin, P.E., naturally infected chimpanzee. J. Infect. Miranda, M.E.G., Trappier, S.G., Khan, Dis. 179: S54-S59. A.S., Peters, C.J. and Nichol, S.T. (1999). Detection and Molecular Xu, L., Sanchez, A., Yang, Z., Zaki, S.R., Characterization of Ebola viruses Nabel, E.G., Nichol, S.T. and Nabel, causing disease in human and G.J. (1998). Immunization for Ebola nonhuman primates. J. Infect. Dis. 179: virus infection. Nat. Med. 4: 37-42. S164-S169. Yang, Z.H., Duckers, H.J., Sullivan, N.J., Sanchez, A.A., Khan, A.S., Zaki, S.R., Nabel, Sanchez, A., Nabel, E.G. and Nabel, G.J. J.B., Ksiazek, T.G. and Peters, C.J. (2000). Identification of the Ebola virus (2001). Filoviridae: Marburg and Ebola glycoprotein as the main viral viruses, p. 1279-1304. In D.M. Knipe determinant of vascular cell cytotoxicity and P.M. Howley (ed.), Fields Virology. and injury. Nat. Med. 6: 886-889. Lippincott, Williams & Wilkins, Philadelphia, PA. WHO (2014). Ebola viral disease. WHO Fact Sheet No.103. (Unpublished).