Portal de Periódicos da CAPES

Ebola Virus Disease

2014; Pulsus Group; Volume: 25; Issue: 3 Linguagem: Inglês

10.1155/2014/527378

1918-1493

Kevin B. Laupland, Louis Valiquette,

Disaster Response and Management

E bola virus disease (Ebola hemorrhagic fever) first appeared in 1976 with two concurrent outbreaks of acute viral hemorrhagic fever involving 284 cases (151 deaths [53%]) centred in Nzara, Sudan (1), and 318 cases (280 deaths [88%]) in Yambuku (near the Ebola River), Democratic Republic of Congo (2).Since these original cases, there have been approximately 20 other outbreaks occurring through to 2013, involving nearly 2500 cases in the Democratic Republic of Congo, Sudan, Gabon, Côte d'Ivoire, Uganda and the Republic of the Congo (3).Since January 2014, a new outbreak has been identified in several West African countries (3).As of April 16, 2014, 197 cases (122 deaths [62%]) have been reported by the Ministry of Health of Guinea, of which 101 have been laboratory confirmed (56 deaths [55%]) (3).The Ministry of Health and Social Welfare of Liberia has reported 27 clinical cases with associated deaths in 13 (48%) (3).Six and 12 suspected cases occurring in the neighbouring countries of Mali and Sierra Leone have been observed, respectively, but have not been laboratory confirmed (3).The genus Ebolavirus belongs to the Filoviridae family, along with the genus Marburgvirus.There are five species of Ebola virus including Bundibugyo, Zaire, Sudan, Côte d'Ivoire (Taï Forest) and Reston ebolaviruses.The former three have been responsible for the large outbreaks that have occurred in Africa, whereas the Reston ebolavirus has been observed in animals in Asia but not as a cause of human disease (4).Fruit bats of the Pteropodidae family, including the species Hypsignathus monstrosus, Epomops franqueti and Myonycteris torquata, are believed to be the natural hosts of Ebola viruses, with humans and other mammals serving as accidental hosts (5).A range of animal accidental hosts have been documented, and Ebola virus has been implicated as one of the major causes of decline of African chimpanzee and gorilla populations in recent decades (6,7).Ebola virus is transmitted to humans through close contact with blood and bodily fluids from another infected human or animal, either by direct contact or indirectly from a contaminated environment.The incubation period for Ebola virus disease ranges from two to 21 days and is characterized by fever, headache, myalgias and gastrointestinal symptoms (3).Multisystem involvement with hypotension and respiratory, kidney and liver failure may ensue, as well as internal and external bleeding (8).In one detailed prospective assessment of 26 of 30 hospitalized patients with Ebola virus disease during the 2007-2008 Bundibugyo outbreak, the median duration of symptoms was nine days from onset to death and 10 days from onset to discharge for survivors (9).The most common self-reported symptoms were fever (73%), nausea/vomiting (73%) and diarrhea (73%), abdominal pain (60%) and conjunctivitis (33%).The most commonly clinically documented features were severe headache (95%), asthenia (86%), myalgia (76%), dysphagia (71%), anorexia (71%) and diarrhea (67%).Among the cohort of 26 cases, seven exhibited hemorrhagic features, which included melena, prolonged bleeding at injection sites, hematemesis, bleeding gums, hemoptysis, hematuria and postpartum vaginal bleeding (9).