Ebola
What is Ebola?
Ebola virus disease is previously known as Ebola hemorrhagic disease. It is a very severe disease with mortality up to 90%. Ebola first appeared in 1976 mainly in Nzara, Sudan, and in Yambuku, Democratic Republic of Congo. It started from the village near the Ebola River and hence it got its name Ebola.
Ebola virus comprises of 5 distinct species: Bundibugyo ebolavirus (BDBV), Zaire ebolavirus (EBOV), Reston ebolavirus (RESTV), Sudan ebolavirus (SUDV) and Taï Forest ebolavirus (TAFV). BDBV, EBOV and SUDV have been associated with the outbreaks in Africa.
What is Ebola?
Ebola virus disease is previously known as Ebola hemorrhagic disease. It is a very severe disease with mortality up to 90%. Ebola first appeared in 1976 mainly in Nzara, Sudan, and in Yambuku, Democratic Republic of Congo. It started from the village near the Ebola River and hence it got its name Ebola.
Ebola virus comprises of 5 distinct species: Bundibugyo ebolavirus (BDBV), Zaire ebolavirus (EBOV), Reston ebolavirus (RESTV), Sudan ebolavirus (SUDV) and Taï Forest ebolavirus (TAFV). BDBV, EBOV and SUDV have been associated with the outbreaks in Africa.
Where does Ebola come from?
Fruit bats of the Pteropodidae family are natural hosts of the Ebola virus. Hunters in Africa hunt down wild infected “bushmeat” which include infected chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines. When these bushmeat is not properly cooked or if the hunters get into contact with body secretions and fluids of infected animals, they can get infected. Then from there, the infected person can spread to another person by direct contact.
Fruit bats of the Pteropodidae family are natural hosts of the Ebola virus. Hunters in Africa hunt down wild infected “bushmeat” which include infected chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines. When these bushmeat is not properly cooked or if the hunters get into contact with body secretions and fluids of infected animals, they can get infected. Then from there, the infected person can spread to another person by direct contact.
Human to human transmission of Ebola Virus
Ebola virus is transmitted from human to human by contact with contaminated body fluids (blood, sexually fluid, secretions, organ and other body fluids like vomitus). It can also be transmitted indirectly via contaminated environments/ places with infected fluids. During burial ceremonies, direct contact with an infected body may also play a role in transmission of the disease.
Ebola virus DO NOT spread via respiratory air droplets unlike SARS and MERS. Men who have recovered can still transmit the Ebola virus sexually from the semen secreted up till 7 weeks post recovery from illness.
RESTV (an Ebola species) appears less capable of causing disease in humans as some workers who are in contact with infected pigs and monkeys do not develop the disease.
Ebola virus is transmitted from human to human by contact with contaminated body fluids (blood, sexually fluid, secretions, organ and other body fluids like vomitus). It can also be transmitted indirectly via contaminated environments/ places with infected fluids. During burial ceremonies, direct contact with an infected body may also play a role in transmission of the disease.
Ebola virus DO NOT spread via respiratory air droplets unlike SARS and MERS. Men who have recovered can still transmit the Ebola virus sexually from the semen secreted up till 7 weeks post recovery from illness.
RESTV (an Ebola species) appears less capable of causing disease in humans as some workers who are in contact with infected pigs and monkeys do not develop the disease.
Ebola Symptoms and Signs
From the time a person is infected to development of symptoms, this incubation period ranges from 2 to 21 days. Ebola will cause an acute viral illness starting with fever, headache, weakness, muscle pain and sore throat.
The Ebola virus attacks the immune system and in particularly the T lymphocytes just like HIV does. However Ebola destroys the T cells very aggressively.
Soon the second phase comes in, the infected person will experience vomiting and diarrhea and is now very highly infectious. Blood tests will review low platelet count, low white blood cell count and elevated liver enzyme levels.
After this stage they enter the last stage called the “cytokine storm” which will determine if they survive or they will succumb to the disease. In this phase, the immune system starts to attack every body organ and blood vessels. This results in internal and external bleeding. Organs like kidneys and liver may be damaged too. This is the peak of the infectiousness of Ebola virus.
From the time a person is infected to development of symptoms, this incubation period ranges from 2 to 21 days. Ebola will cause an acute viral illness starting with fever, headache, weakness, muscle pain and sore throat.
The Ebola virus attacks the immune system and in particularly the T lymphocytes just like HIV does. However Ebola destroys the T cells very aggressively.
Soon the second phase comes in, the infected person will experience vomiting and diarrhea and is now very highly infectious. Blood tests will review low platelet count, low white blood cell count and elevated liver enzyme levels.
After this stage they enter the last stage called the “cytokine storm” which will determine if they survive or they will succumb to the disease. In this phase, the immune system starts to attack every body organ and blood vessels. This results in internal and external bleeding. Organs like kidneys and liver may be damaged too. This is the peak of the infectiousness of Ebola virus.
Differential diagnosis
The differential diagnosis for Ebola virus include malaria, shigellosis, typhoid fever, leptospirosis, cholera, rickettsiosis, plague, meningitis, hepatitis and other viral hemorrhagic fevers. These diseases may present some similar symptoms as Ebola virus.
The differential diagnosis for Ebola virus include malaria, shigellosis, typhoid fever, leptospirosis, cholera, rickettsiosis, plague, meningitis, hepatitis and other viral hemorrhagic fevers. These diseases may present some similar symptoms as Ebola virus.
Diagnosis of Ebola
Ebola virus can be isolated and diagnosed by laboratory tests like:
· antibody-capture enzyme-linked immunosorbent assay (ELISA)
· serum neutralization test
· reverse transcriptase polymerase chain reaction (RT-PCR) assay
· antigen detection tests
· virus isolation by cell culture
· electron microscopy
However extracting blood sample and testing the blood is highly contagious at this stage. It should only be done under maximum containment situations and with person protective equipment.
Ebola virus can be isolated and diagnosed by laboratory tests like:
· antibody-capture enzyme-linked immunosorbent assay (ELISA)
· serum neutralization test
· reverse transcriptase polymerase chain reaction (RT-PCR) assay
· antigen detection tests
· virus isolation by cell culture
· electron microscopy
However extracting blood sample and testing the blood is highly contagious at this stage. It should only be done under maximum containment situations and with person protective equipment.
Treatment
There is currently no specific treatment for Ebola. Medical care only includes supportive care which includes intravenous hydration, procoagulants to control bleeding, pain management and correction of electrolytes. There is currently no vaccine against Ebola.
Trial drugs like Zmapp are still in experimental phase. No human trial on the medication has been conducted yet. However due to the rapid spread of the disease, more of the drug is being produced to be try on the victims of Ebola virus.
Another possibility to look at in future, is to use the antibodies in Ebola virus survivors to be injected into those infected. When this serum was used in patients during the 1995 Ebola outbreak in the Democratic Republic of Congo, it was found that 7 out of 8 survived.
There is currently no specific treatment for Ebola. Medical care only includes supportive care which includes intravenous hydration, procoagulants to control bleeding, pain management and correction of electrolytes. There is currently no vaccine against Ebola.
Trial drugs like Zmapp are still in experimental phase. No human trial on the medication has been conducted yet. However due to the rapid spread of the disease, more of the drug is being produced to be try on the victims of Ebola virus.
Another possibility to look at in future, is to use the antibodies in Ebola virus survivors to be injected into those infected. When this serum was used in patients during the 1995 Ebola outbreak in the Democratic Republic of Congo, it was found that 7 out of 8 survived.
Recovery from Ebola
Ebola virus mortality rate is as high as 90%. Ebola virus survivors may still be infectious for a while so they still need to be isolated and quarantined. Sexual fluids like semen can still be infectious up to 7 weeks post illness. Contaminated items like clothings, personal belongings and household items of quarantined should be burned.
Ebola virus mortality rate is as high as 90%. Ebola virus survivors may still be infectious for a while so they still need to be isolated and quarantined. Sexual fluids like semen can still be infectious up to 7 weeks post illness. Contaminated items like clothings, personal belongings and household items of quarantined should be burned.
Prevention and control of Ebola Virus
Should an outbreak happens in the farm, the premises should be quarantined with immediate effect. Infected animals should be culled and properly incinerated to prevent animal to human transmission.
Farmers should be taught proper protective equipment during handling of animals and also during slaughtering. They should be educated that consumption of fresh blood, raw milk and animal tissue is very unsafe.
In Africa, where Ebola outbreak is spreading, public education is very important. People should not contact or eat infected animals like bats/monkeys or apes. All bush meat eaten should be thoroughly cooked before consumption.
Close physical contact with Ebola patients should be avoided especially the body fluids of infected persons. Face protection (face shield, mask and goggles), gloves and appropriate personal protective equipment (e.g. long sleeved protective gowns) should be worn when taking care of infected patients. Regular hand washing is a must. Health care workers should also practice safe infection practices.
Laboratory blood samples taken from infected persons should be handled with care and only be done by trained professionals and in a highly secured laboratory. People who have died from Ebola should be promptly and safely buried.
Should an outbreak happens in the farm, the premises should be quarantined with immediate effect. Infected animals should be culled and properly incinerated to prevent animal to human transmission.
Farmers should be taught proper protective equipment during handling of animals and also during slaughtering. They should be educated that consumption of fresh blood, raw milk and animal tissue is very unsafe.
In Africa, where Ebola outbreak is spreading, public education is very important. People should not contact or eat infected animals like bats/monkeys or apes. All bush meat eaten should be thoroughly cooked before consumption.
Close physical contact with Ebola patients should be avoided especially the body fluids of infected persons. Face protection (face shield, mask and goggles), gloves and appropriate personal protective equipment (e.g. long sleeved protective gowns) should be worn when taking care of infected patients. Regular hand washing is a must. Health care workers should also practice safe infection practices.
Laboratory blood samples taken from infected persons should be handled with care and only be done by trained professionals and in a highly secured laboratory. People who have died from Ebola should be promptly and safely buried.
Who is a suspect case of Ebola Virus?
As suspect case is:
· A person with fever (> 38 degrees) or history of sudden onset of fever AND with positive travel history to affected area in West Africa (Liberia, Guinea, Nigeria and Sierra Leone) within 21 days
Or
· A person with fever (> 38 degrees) or history of sudden onset of fever AND has been exposed to a known or suspected case of Ebola virus patient.
Who is a confirmed case of Ebola virus?
A confirmed case of Ebola virus is one who has laboratory test confirmation of the presence of the Ebola Virus.
As suspect case is:
· A person with fever (> 38 degrees) or history of sudden onset of fever AND with positive travel history to affected area in West Africa (Liberia, Guinea, Nigeria and Sierra Leone) within 21 days
Or
· A person with fever (> 38 degrees) or history of sudden onset of fever AND has been exposed to a known or suspected case of Ebola virus patient.
Who is a confirmed case of Ebola virus?
A confirmed case of Ebola virus is one who has laboratory test confirmation of the presence of the Ebola Virus.
