Ebola Virus Disease(EVD)
Ebola Virus Disease (EVD) also known as Ebola hemorrhagic fever(EHF) is one of the viral hemorrhagic fevers which affects a person’s blood system
It is a severe, often fatal illness in humans and non-human primates (monkeys, gorillas, and chimpanzees)
It is caused by infection with a virus which is transmitted to people from wild animals and spreads in the human population.
EVD is fatal up to 90% of the cases who are infected.
EVD outbreaks(sudden occurrence of disease) are known to occur primarily in villages of Central and West Africa, near tropical rainforests.
The largest outbreak is the ongoing 2014 West Africa Ebola Outbreak, which has affected Guinea, Liberia, Sierra Leone and Nigeria. As of August 2014, more than 1,750 cases have been suspected.
Severely infected patients require intensive supportive care. No specific treatment or vaccine is available for this disease
History
EVD was first originated in Sudan and the Democratic Republic of Congo. The disease typically occurs in outbreaks in tropical regions of Sub Saharan Africa. Fewer than 1000 people have been infected every year from 1976 till 2013. Ebola virus was first found in 1976 during the outbreak of Ebola hemorrhagic fever in Zaire and Sudan. The name of the disease originates from one of those first recorded outbreaks in 1976 in the Democratic Republic of the Congo (then Zaire), which situated on the Ebola River.
Symptoms
Fever
Headache
Weakness
Joint and muscle pain
Diarrhoea
Vomiting
Pain in stomach
Loss of appetite
This disease further progresses to the bleeding phase which causes external bleeding from eyes, nose ears as well as bleeding inside the body.
Symptoms may appear anywhere from 2 to 21 days after exposure to virus though 8-10 days is most common after exposure to Ebola virus.
Causes
EVD is caused by four of five viruses in the genus Ebola virus, family Filoviridae, order Mononegavirales. The four disease-causing viruses in humans are as follows
Bundibugyo Ebola virus (BDBV)
Zaire Ebola virus/Ebola virus (EBOV)
Sudan Ebola virus (SUDV)
Taï Forest Ebola virus (TAFV)
BDBV,EBOV,SUDV are most dangerous viruses as well responsible for causing large number of outbreaks in Africa.
The fifth virus called Reston Ebola virus (RESTV) is known to cause disease in non human primates (monkeys, gorillas, and chimpanzees)
Transmission
A. Primary Source of Infection-The virus is transmitted from animal to human in which the person gets infected with a virus of the family Filoviridae, genus Ebolavirus. The virus is zoonotic (animal-borne) with bats being the most likely reservoir of infection.
B. Secondary Source of Infection-The virus can be transmitted from human through-
Direct contact the body fluids such as blood, sweat, saliva, semen or other body discharges of an infected person
Exposure to objects like needles that have been contaminated with an infected person
The dead body of the infected person can also be a source of infection.
Facts about Transmission
Ebola can't be transmitted through the air.
It can't be transmitted through water.
It can't be transmitted through food.
This clearly states that it is not a food-borne, waterborne and an air-borne disease.
Risk of Exposure
During the outbreak, those at higher risk of infection are-
a) Health workers
b) Family and others who are in close contact of infected individuals
c) Mourners who come in direct contact with the bodies of the deceased in burial ceremonies
d) Travellers who visit disease-prone areas.
Diagnosis
It is difficult to diagnose the disease in the early stages of infection as the early symptoms are non-specific to Ebola virus infection. However, it can be diagnosed through several lab tests such as-
Antibody-capture enzyme-linked immunosorbent assay (ELISA)
Antigen detection tests
Polymerase Chain Reaction(PCR)
Virus isolation by cell culture.
Electron microscopy
Treatments
No vaccine for Ebola Virus Disease is available. Efforts are going on to develop a vaccine. There is no specific treatment for this disease. However, The standard treatment for Ebola virus Disease includes an intensive supportive therapy. This consists of:
balancing the patient’s fluids and electrolytes
maintaining their oxygen status and blood pressure
treating them for any other infections
It is very important that the treatment of Ebola HF is timely since it is difficult to diagnose the diseases in the early stages of infection. The early symptoms such as headache and fever are nonspecific and can be easily misunderstood for any other disease. The prevention of this diseases is a challenging task because it is still not certain as to how people are infected with Ebola HF.
Emergency Care Set Up in India
WHO has declared that the outbreak of Ebola disease virus (EVD) in west Africa was the “most complex outbreak which has lead to public health emergency”. A global health emergency, the government has opened a 24 hour 'Emergency Helpline Operation Centre' which provides the most advanced tracking and surveillance system. Ram Manohar Lohia Hospital and All India Institute Of Medical Sciences in New Delhi have been identified for management and treatment of individuals with EVD. The helpline numbers are (011)-23061469, 3205 and 1302.
Preventions
The primary preventive measures comprise of isolation precautions and barrier nursing techniques.
Isolation
Quarantine, a state of enforced isolation, is effective in decreasing the spread of disease and illness especially in the case of communicable diseases wherein the infected individuals are restricted to come in contact with those who are healthy.Generally, the duration of quarantine period is the length of disease's incubation period(period between the infection and appearance of symptoms) which is 2-21 days in case of Ebola virus disease.
2. Barrier nursing techniques include:
Wear protective clothing (such as masks, gloves, gowns, and goggles)
Use of infection-control measures (such as complete equipment sterilization and routine use of disinfectant)
Fumigate your environment and disinfect your surroundings. The virus cannot survive disinfectants, heat, sunlight, detergents and soaps.
Dead bodies can transmit Ebola. Don't touch them without a protective gear or better avoid them altogether.
Wash your hands with soap or use sanitizer.
References
WHO
CDC
CDC