How to prevent deadly Ebola infection
People are infectious as long as their blood and secretions contain the virus. Ebola virus has been isolated from the semen of a man infected in a laboratory 61 days after the onset of illness.
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Ebola first appeared in 1976 in two simultaneous outbreaks in Nzara, Sudan and Yambuku, Democratic Republic of Congo. The second outbreak was in a village near the Ebola River, which is named after it.
Ebolavirus is one of three genera of viruses in the family Filoviridae (filovirus), along with Marburgvirus and Cuevavirus. Ebolavirus includes five distinct species:
- Bundibugyo ebolavirus (BDBV)
- Zaire ebolavirus (EBOV)
- Reston ebolavirus (RESTV)
- Sudan ebolavirus (SUDV)
- Tai Forest ebolavirus (TAFV).
BDBV, EBOV, and SUDV have all been associated with large Ebola outbreaks in Africa, whereas RESTV and TAFV have not.
RESTV, which has been detected in the Philippines and China, can infect humans, but to date there have been no reports of human illness or death due to this species.
Transmission
Ebola is transmitted to humans through close contact with the blood, secretions, organs, or other bodily fluids of infected animals. In Africa, infection has been reported from the transport of sick or dead chimpanzees, orangutans, fruit bats, monkeys, forest antelope, and porcupines in the rainforest.
Ebola then spreads in the community through person-to-person transmission, with infection resulting from direct contact (through open wounds on the skin or mucous membranes) with the blood, secretions, organs or other body fluids of an infected person, and through indirect contact with environments contaminated with these fluids.
Funerals in which attendees have direct contact with the body of the deceased also play a role in Ebola transmission.
Men who have recovered from the disease can still transmit the virus through semen for up to 7 weeks after recovery.
Health care workers are frequently infected while treating patients with suspected or confirmed Ebola. Infection occurs through direct contact with patients when strict precautions are not taken.
Signs and symptoms
Ebola is a severe acute viral illness typically characterized by sudden high fever, extreme fatigue, muscle pain, headache, and sore throat. This is followed by vomiting, diarrhea, impaired kidney and liver function, and in some cases internal and external bleeding. Laboratory findings include leukopenia and thrombocytopenia and elevated liver enzymes.
People are infectious as long as their blood and secretions contain the virus. Ebola virus has been isolated from the semen of a man infected in a laboratory 61 days after the onset of illness.
The incubation period, that is, the time from infection with the virus to the appearance of symptoms, is 2 to 21 days.
Diagnose
Other diseases that should be ruled out before a diagnosis of Ebola can be made include: malaria, typhoid, shigellosis, cholera, leptospirosis, plague, rickettsioses, relapsing fever, meningitis, hepatitis, and other viral hemorrhagic fevers.
Ebola virus infection can be diagnosed in the laboratory using a variety of tests, including enzyme-linked immunosorbent assay (ELISA); antigen detection tests; serum neutralization tests; reverse transcription polymerase chain reaction (RT-PCR); electron microscopy; and virus isolation by cell culture.
Patient specimens pose an extremely high biological risk; testing must be conducted under maximum biosafety conditions.
Vaccines and treatment
There is currently no vaccine for Ebola. Several vaccines are being tested, but none are available for clinical use.
Severely ill patients require intensive supportive care. Patients are often dehydrated and require oral rehydration with electrolyte solutions or intravenous fluids.
There is no specific treatment for the disease. Several new drug regimens are being evaluated.
Natural host of Ebola virus
In Africa, fruit bats, especially species of the genera Hypsignathus monstrosus, Epomops franqueti and Myonycteris torquata, are considered natural hosts of Ebola virus. As a result, the geographic distribution of Ebola virus may overlap with the range of bats.
Prevention
Reducing the risk of Ebola infection in humans
In the absence of effective treatment and human vaccine, raising awareness of Ebola risk factors and personal protective measures is the only way to reduce human infection and death.
In Ebola outbreak areas, public education messages to reduce risk focus on the following elements:
- Reduce the risk of disease transmission from wild animals to humans through contact with infected fruit bats or monkeys/primates and consumption of their raw meat. Gloves and appropriate protective clothing should be worn when handling animals. Animal products (blood and meat) should be thoroughly cooked before consumption.
- Reduce the risk of disease transmission from person to person in the community due to direct contact or close contact with sick people, especially with the body fluids of sick people.
Close physical contact with Ebola patients should be avoided.
Gloves and appropriate personal protective equipment should be worn when caring for a sick person at home.
Wash your hands regularly after visiting patients in the hospital, as well as after caring for sick people at home.
-Communities affected by Ebola should inform the public about the nature of the disease and about measures to contain the outbreak, including burial of the dead. People who die from Ebola should be promptly and safely buried.
African pig farms may play a role in amplifying the scale of the outbreak due to the presence of fruit bats on these farms. Appropriate biosecurity measures should be implemented to limit the spread of infection.
For RESTV, focus on reducing the risk of pig-to-human transmission due to unsafe animal husbandry and slaughtering practices, as well as unsafe consumption of fresh blood products, raw milk or animal meat. Gloves and appropriate protective clothing should be worn when handling sick animals or animal tissues and when slaughtering animals. In areas where RESTV has been reported in pigs, all animal products (blood, meat and milk) should be thoroughly cooked before consumption.
Infection prevention in healthcare facilities
Human-to-human transmission of Ebola virus is primarily associated with direct contact with blood and body fluids. Infections have been reported among health care workers when appropriate infection control measures are not in place.
Early identification of Ebola patients is not always possible because the initial symptoms are often non-specific. Therefore, health care workers need to apply infection control measures to all patients – regardless of diagnosis – at all times and in all settings.
These measures include hand hygiene, respiratory hygiene, use of personal protective equipment (according to the risk of spillage or other contact with contaminated materials), safe injection practices, and safe burial practices.
In addition to the basic measures outlined above, health care workers caring for patients with suspected or confirmed Ebola virus infection should apply additional infection prevention measures to avoid any exposure to the patient's blood and body fluids and direct unprotected contact with the contaminated environment. When in close contact (within 1 meter) with an Ebola patient, health care workers should wear face protection (face shield or medical mask and goggles), a clean, non-sterile gown, and gloves (sterile gloves for some procedures).
Laboratory workers are also at risk. Samples from animals and people suspected of having Ebola should be transported by trained personnel and processed in a properly equipped laboratory.
According to Hanoimoi
