What is ebola virus

Ebola virus disease (EVD), formerly known as Ebola hemorrhagic fever, is a severe, often fatal illness in humans.

EVD outbreaks have a case fatality rate of up to 90%.

EVD outbreaks occur primarily in remote villages in Central and West Africa, near tropical rainforests.

The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.

Fruit bats of the Pteropodidae family are considered to be the natural host of the Ebola virus.

Ebola is however NOT AN AIRBORNE VIRUS

EXTREMELY deadly:

About 90% of people that catch Ebola will die from it.

It’s one of the deadliest diseases in the world, killing in just a few weeks.

EBOLA VIRUS ANTIBODIES IN FRUIT BATS, BANGLADESH

To determine geographic range for Ebola virus:

276 bats in Bangladesh

Five (3.5%) bats were positive for antibodies against Ebola Zaire and

Reston viruses

These bats might be a reservoir for Ebola or

Ebola-like viruses, and extend the range of

filoviruses to mainland Asia.

Filoviruses are zoonotic pathogens that cause episodic, lethal, hemorrhagic outbreaks among humans and nonhuman primates and case-fatality rates up to 80%

Despite their role in human disease, natural reservoirs of filoviruses have remained elusive for decades. Reports suggest that bats (Order Chiroptera) are the primary natural hosts, including Old World insectivorous bats (genera Rhinolophus and Miniopterus) and frugivorous bats (familyPteropodidae).

Fruit bats of the genus Rousettus have been implicated as a reservoir of filoviruses in Africa (4–7) and REBOV in the Philippines (8).

We screened bats of several species from Bangladesh for Ebola virus infection to determine whether the geographic range of this virus extends to southern Asia.

Fifteen (11%) of 141 R. lescehnaulti, 6 (8%) of 75 Cynopterus spp., and 4 (7%) of 56 M. lyra bats were potentially positive after initial screening.

throat, urine/urogenital, and fecal swab specimens were also collected which were placed in 750 µL of NucliSENS lysis buffer. All samples were collected in cryovials, placed in liquid

nitrogen in the field, and maintained at −80°C until testing.

50–800 µL of blood were collected from brachial or cephalic veins of each bat, and diluted it 1:4 with phosphate-buffered saline in the field before serum was separated, as described

Conclusion:Our study provides evidence of Ebola virus infection in wildlife from mainland Asia and corroborates the observation that filoviruses are harbored across a much larger geographic range then assumed. Preferential reactivity to ZEBOV suggests exposure to an Ebola virus that is distinct from REBOV, the only filovirus currently found in Asia.

We consider the likelihood of cross-reactivity with MARV as low because there is only a 35% aa identity between nucleoprotein genes of REBOV/ZEBOV and MARV. However, we cannot rule out co-infection with multiple filoviruses.

Genus Ebolavirus is 1 of 3 members of the Filoviridae family (filovirus), along with genus Marburgvirus and genus

Cuevavirus. Genus Ebolavirus comprises 5 distinct species:

Bundibugyo ebolavirus (BDBV)

Zaire ebolavirus (EBOV)

Reston ebolavirus (RESTV)

Sudan ebolavirus (SUDV)

Taï Forest ebolavirus (TAFV).

BDBV, EBOV, and SUDV have been associated with large EVD outbreaks in Africa, whereas RESTV and TAFV have not. The RESTV species, found in Philippines and the People’s Republic of China, can infect humans, but no illness or death in humans from this species has been reported to date.

Transmission:Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals.

In Africa, infection has been documented through the handling of infected chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead or in the rainforest.

Ebola then spreads in the community through human-to-human transmission, with infection resulting from direct contact (through broken skin or mucous membranes) with the blood, secretions, organs or other bodily fluids of infected people, and indirect contact with environments contaminated with such fluids.

Burial ceremonies in which mourners have direct contact with the body of the deceased person can also play a role in the transmission of Ebola.

Men who have recovered from the disease can still transmit the virus through their semen for up to 7 weeks after recovery from illness.

Signs and symptoms

EVD is a severe acute viral illness often characterized by the sudden onset of fever, intense weakness, muscle pain, headache and sore throat.

This is followed by vomiting, diarrhea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding. Laboratory findings include low white blood cell and platelet counts and elevated liver enzymes.

People are infectious as long as their blood and secretions contain the virus. Ebola virus was isolated from semen 61 days after onset of illness in a man who was infected in a laboratory.

The incubation period, that is, the time interval from infection with the virus to onset of symptoms, is 2 to 21 days.

Diagnosis• Other diseases that should be ruled out before a diagnosis of EVD can

be made include: malaria, typhoid fever, shigellosis, cholera, leptospirosis, plague, rickettsiosis, relapsing fever, meningitis, hepatitis and other viral hemorrhagic fevers.Ebola virus infections can be diagnosed definitively in a laboratory through several types of tests:

antibody-capture enzyme-linked immunosorbent assay (ELISA)

antigen detection tests

serum neutralization test

reverse transcriptase polymerase chain reaction (RT-PCR) assay

electron microscopy

virus isolation by cell culture

Vaccine and treatment

No licensed vaccine for EVD is available. Several vaccines are being tested, but none are available for clinical use.

Severely ill patients require intensive supportive care. Patients are frequently dehydrated and require oral rehydration with solutions containing electrolytes or intravenous fluids.

No specific treatment is available. New drug therapies are being evaluated.

Natural host of Ebola virus

In Africa, fruit bats, particularly species of the genera Hypsignathus monstrosus, Epomops

franqueti and Myonycteris torquata, are considered possible natural hosts for Ebola

virus. As a result, the geographic distribution of Ebolaviruses may overlap with the range of

the fruit bats.

Ebola virus in animals

RESTV has caused severe EVD outbreaks in macaque monkeys (Macaca fascicularis) farmed in Philippines and detected in monkeys imported into the USA in 1989, 1990 and 1996, and in monkeys imported to Italy from Philippines in 1992.

Since 2008, RESTV viruses have been detected during several outbreaks of a deadly disease in pigs in People’s Republic of China and Philippines. Asymptomatic infection in pigs has been reported and experimental inoculations have shown that RESTV cannot cause disease in pigs.

Prevention and Control

Controlling Reston ebola virus in domestic animals

No animal vaccine against RESTV is available. Routine cleaning and disinfection of pig or monkey farms (with sodium hypochlorite or other detergents) should be effective in inactivating the virus.

If an outbreak is suspected, the premises should be quarantined immediately. Culling of infected animals, with close supervision of burial or incineration of carcasses, may be necessary to reduce the risk of animal-to-human transmission. Restricting or banning the movement of animals from infected farms to other areas can reduce the spread of the disease.

As RESTV outbreaks in pigs and monkeys have preceded human infections, the establishment of an active animal health surveillance system to detect new cases is essential in providing early warning for veterinary and human public health authorities.

Reducing the risk of Ebola infection in peopleIn the absence of effective treatment and a human vaccine, raising awareness of the risk factors for Ebola infection and the protective measures individuals can take is the only way to reduce human infection and death.Reducing the risk of wildlife-to-human transmission from contact with infected fruit bats or monkeys/apes 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 in the community arising from direct or close contact with infected patients, particularly with their bodily fluids.

Close physical contact with Ebola patients should be avoided.

Gloves and appropriate personal protective equipment should be worn when taking care of ill patients at home.

Regular hand washing is required after visiting patients in hospital, as well as after taking care of patients at home.

Communities affected by Ebola should inform the population about the nature of the disease and about outbreak containment measures, including burial of the dead.

People who have died from Ebola should be promptly and safely buried.