Ebola virus disease Key facts:
- Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a rare but severe, often fatal illness in humans.
- The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.
- The average EVD case fatality rate is around 50%. Case fatality rates have varied from 25% to 90% in past outbreaks.
- Community engagement is key to successfully controlling outbreaks.
- Good outbreak control relies on applying a package of interventions, namely case management, infection prevention and control practices, surveillance and contact tracing, a good laboratory service, safe and dignified burials and social mobilisation.
- Vaccines to protect against Ebola are under development and have been used to help control the spread of Ebola outbreaks in Guinea and in the Democratic Republic of the Congo (DRC).
- Early supportive care with rehydration, symptomatic treatment improves survival. There is no licensed treatment proven to neutralize the virus but a range of blood, immunological and drug therapies are under development.
- Pregnant and breastfeeding women with Ebola should be offered early supportive care. Likewise vaccine prevention and experimental treatment should be offered under the same conditions as for non-pregnant population.
Ebola virus disease (EVD) is a viral haemorrhagic fever of humans and other primates caused by ebola viruses. Signs and symptoms typically start between two days and three weeks after contracting the virus with a fever, sore throat, muscular pain, and headaches. Then, vomiting, diarrhea and rash usually follow, along side decreased function of the liver and kidneys. At this point , some people begin to bleed both internally and externally. The disease features a high risk of death, killing between 25 and 90 per cent of these infected, with a mean of about 50 per cent.
The disease was first identified in 1976 in two simultaneous outbreaks, one in Nzara, and therefore the other in Yambuku, a village near the Ebola River from which the disease takes its name. EVD outbreaks occur intermittently in tropical regions of Sub-Saharan Africa . Between 1976 and 2013, the planet Health Organization reports a complete of 24 outbreaks involving 1,716 cases.
The largest outbreak so far was the epidemic in West Africa , which occurred from December 2013 to January 2016 with 28,616 cases and 11,310 deaths. it had been declared not an emergency on 29 March 2016.
DR Congo reported a fresh Ebola outbreak in its northwest on June 01, 2020, the newest health emergency for a rustic already fighting a plague of the deadly fever within the east also as a surging number of coronavirus infections.
Ebola Virus Disease Tansmission
It is thought that fruit bats of the Pteropodidae family are natural Ebola virus hosts. Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals like fruit bats, chimpanzees, gorillas, monkeys, forest antelope or porcupines found ill or dead or within the rainforest.
Ebola then spreads through human-to-human transmission via direct contact (through broken skin or mucous membranes) with:
- Blood or body fluids of an individual who is sick with or has died from Ebola.
- Objects that are contaminated with body fluids (like blood, feces, vomit) from an individual sick with Ebola or the body of an individual who died from Ebola
Health-care workers have frequently been infected while treating patients with suspected or confirmed EVD. this happens through close contact with patients when infection control precautions aren’t strictly practiced.
Burial ceremonies that involve direct contact with the body of the deceased also can contribute within the transmission of Ebola.
People remain infectious as long as their blood contains the virus.
Pregnant women who get acute Ebola and get over the disease should carry the virus in breastmilk, or in pregnancy related fluids and tissues. This poses a risk of transmission to the baby they carry, and to others. Women who become pregnant after surviving Ebola disease aren’t in danger of carrying the virus.
If a breastfeeding woman who is recovering from Ebola wishes to continue breastfeeding, she should be supported to try to to so. Her breast milk must be tested for Ebola before she will start.
Ebola Virus Disease Symptoms
The incubation period, that is, the time interval from infection with the virus to onset of symptoms, is from 2 to 21 days. A person infected with Ebola cannot spread the disease until they develop symptoms.
Symptoms of Ebola virus disease can be sudden and include:
- Muscle pain
- Sore throat
This is followed by:
- Symptoms of impaired kidney and liver function
- In some cases, both internal and external bleeding (for example, oozing from the gums, or blood in the stools).
- Laboratory findings include low white blood cell and platelet counts and elevated liver enzymes.
Ebola Virus Disease Treatment
According to Who, Supportive care – rehydration with oral or intravenous fluids – and treatment of specific symptoms improves survival. There is as yet no proven treatment available for EVD. However, a range of potential treatments including blood products, immune therapies and drug therapies are currently being evaluated.
In the ongoing 2018-2019 Ebola outbreak in DRC, the first-ever multi-drug randomized control trial is being conducted to evaluate the effectiveness and safety of drugs used in the treatment of Ebola patients under an ethical framework developed in consultation with experts in the field and the DRC.
Pregnant and breastfeeding women with Ebola should be offered early supportive care, like general population. Likewise experimental treatment should be offered under the same conditions as for non-pregnant population.
Ebola Virus Disease Vaccines
According to Who, An experimental Ebola vaccine proved highly protective against EVD in a major trial in Guinea in 2015. The vaccine, called rVSV-ZEBOV, was studied in a trial involving 11 841 people. Among the 5837 people who received the vaccine, no Ebola cases were recorded 10 days or more after vaccination. In comparison, there were 23 cases 10 days or more after vaccination among those who did not receive the vaccine.
The rVSV-ZEBOV vaccine is being used in the ongoing 2018-2019 Ebola outbreak in DRC. Pregnant and breastfeeding women should have access to the vaccine under the same conditions as for the general population.
Initial data indicates that the vaccine is highly effective.
WHO’s Strategic Advisory Group of Experts has stated the need to assess additional Ebola vaccines.
Ebola Virus Disease Prevention and control
Good outbreak control relies on applying a package of interventions, including case management, surveillance and contact tracing, a good laboratory service, safe burials and social mobilisation. Community engagement is key to successfully controlling outbreaks. Raising awareness of risk factors for Ebola infection and protective measures (including vaccination) that individuals can take is an effective way to reduce human transmission. Risk reduction messaging should focus on several factors:
- Reducing the risk of wildlife-to-human transmission from contact with infected fruit bats, monkeys, apes, forest antelope or porcupines and the consumption of their raw meat. Animals should be handled with gloves and other appropriate protective clothing. Animal products (blood and meat) should be thoroughly cooked before consumption.
- Reducing the risk of human-to-human transmission from direct or close contact with people with Ebola symptoms, particularly with their bodily fluids. Gloves and appropriate personal protective equipment should be worn when taking care of ill patients. Regular hand washing is required after visiting patients in hospital, as well as after taking care of patients at home.
- Outbreak containment measures, including safe and dignified burial of the dead, identifying people who may have been in contact with someone infected with Ebola and monitoring their health for 21 days, the importance of separating the healthy from the sick to prevent further spread, and the importance of good hygiene and maintaining a clean environment.
- Reducing the risk of possible sexual transmission, based on further analysis of ongoing research and consideration by the WHO Advisory Group on the Ebola Virus Disease Response, WHO recommends that male survivors of EVD practice safer sex and hygiene for 12 months from onset of symptoms or until their semen tests negative twice for Ebola virus. Contact with body fluids should be avoided and washing with soap and water is recommended. WHO does not recommend isolation of male or female convalescent patients whose blood has been tested negative for Ebola virus.
- Reducing the risk of transmission from pregnancy related fluids and tissue, Pregnant women who have survived Eboa disease need community support to enable them to attend frequent antenatal care (ANC) visits, to handle any pregnancy complications and meet their need for sexual and reproductive care and delivery in a safe way. This should be planned together with the Ebola and Obstetric health care expertise. Pregnant women should always be respected in the sexual and reproductive health choices they make.