Originally posted August 3, 2014.

The last few days, more people have expressed concern over the decision to bring two aid workers who are inflicted with the Ebola virus back to the U.S. for treatment.  Around the water cooler, there are whispers about the virus spreading here on U.S. soil.  On Facebook, people offer their opinion that we shouldn’t bring the infected man and woman back into our borders for fear of an epidemic.  There are even people prophesizing that this is the beginning of the zombie apocalypse, channeling their fear into misguided humor.

It is scary.  This outbreak is the worst in history, killing a reported 729 people and infecting a couple thousand at last count, with no sings of slowing down.  The outbreak has gotten so bad in West African countries like Sierra Leone that the government has quarantined affected communities, saying they’ll send the police or military to enforce the medical segregation if necessary.  But like any medical outbreak or disaster, rumors and half-truths only perpetuate our fear and sometimes make the situation worse.

So for the sake of sharing accurate information and putting your mind at ease, here are the facts about the Ebola Virus:

About the Ebola Virus.
The Ebola virus disease (EVD) is a severe, often fatal illness in humans.  It used to be called Ebola haemorrhagic fever.

It was first discovered in 1976 when two outbreaks occurred at the same time in Sudan and the Democratic Republic of Congo. The village where the outbreak occurred in Congo was near the Ebola River, where the name for the disease comes from.

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

There are actually 5 strains of the Ebola virus.  The strain that’s causing the current outbreak is Zaire Ebolavirus, the deadliest one.

The Ebola virus doesn’t change significantly from year to year like other viruses.  That’s the case with certain flus and SARS, which make them so much harder to identify and treat – and easier to spread.

How many people have been sick and how many have died?
Since it first showed up in 1976, there have been more than 3,270 reported cases and more than2,000 deaths from Ebola, according to the World Health Organization.

In this current outbreak in Africa, roughly2,000, people have been infected and about 729  died, though the numbers are climbing daily.

What’s the survival rate?
It’s important to note that although media reports the mortality rate from Ebola cases as “up to 90%” (or a 10% survival rate,) that does not characterize the actual death toll.  Since Ebola was discovered in 1976, there has been a survival rate of roughly 30%.  The current Ebola outbreak has had a survival rate of about 40 percent, per the latest numbers from the World Health Organization.

Why is the death toll so high?
Mortality rates are so high largely because Ebola outbreaks occur in desperately poor countries and communities where there’s a lack of public health education, sanitation, and medical care.  The countries where this current outbreak took hold, Guinea, Liberia, and Sierra Leone, are among the poorest in the world, with GDP’s per capita less than Haiti.  There is almost no healthcare infrastructure for most of the people there.  Due to this, almost all the medical care for the outbreak has been provided by international Non Governmental Organizations like Doctors Without Borders, who are completely overwhelmed and lack the resources and manpower to address it.

A lack of literacy and education about disease control, cultural norms, and a mistrust of foreign aid workers have exacerbated the problem.

Where does Ebola originate?
Fruit bats of the Pteropodidae family are thought to be the natural host of the Ebola virus.  From there, it infects animals and eventually humans. Outbreaks most often start in remote West African villages near tropical rainforests.

It’s documented that humans have been infected by Ebola by handling of infected chimpanzees, gorillas, fruit bats, monkeys, and other animals found ill or dead or in the rainforest.

Where are Ebola outbreaks reported?
Since its inception in 1976, Ebola outbreaks have mostly occurred in poor Western African countries like Uganda, Gabon, the Democratic Republic of Congo (Zaire,) and Sudan.

It also has shown up in the Philippines and China though no deaths have been reported in those places.

How does it spread among humans?
Ebola spreads through human-to-human transmission by direct contact with bodily fluids.  Being exposed to blood, sweat, vomit, feces, semen, mucous, organs, or other bodily fluids can spread the infection.  Healthcare workers frequently have been infected because of their proximity to Ebola patients, especially in un-sterile field conditions in African villages without proper facilities or resources.

The virus can be transmitted by even touching the bodily fluids of an Ebola patient. If an animal or patient dies, the virus stays alive on a surface for a few days, so even touching bedding, cleaning up waste, or eating infected food or drinking infected water is a danger.  In Africa, some cultures call for burial ceremonies in which mourners have direct contact with the body of the dead person, which also play a role in the transmission of Ebola.

How soon would they be sick and infectious?
Typically, symptoms appear 8-10 days after exposure to the virus, but the incubation period can span two to 21 days.  People usually aren’t infectious until the symptoms of their sickness emerge.

What are the symptoms?
People usually start with a high fever, aches, acute weakness, headache, rashes, and sore throat.  It proceeds to vomiting, diarrhea, rash, impaired kidney and liver function, and in sometimes, both internal and external bleeding.

The problem with diagnosis is that the first symptoms also occur in ailments common to the region so before it can be confirmed as Ebola, malaria, typhoid fever, shigellosis, cholera, leptospirosis, plague, rickettsiosis, relapsing fever, meningitis, hepatitis and other viral haemorrhagic fevers have to be ruled out.

Can it be treated? 
There is no vaccine for the Ebola virus.  Several vaccines are in the testing phase but none are approved for clinical use. The only thing that can be done is to treat the symptoms Ebola causes, which include sever dehydration.

What happened with this current Ebola outbreak?
The current deadly outbreak is in Sierra Leone, Guinea, and Liberia, the first time big Ebola cases have hit those areas.

The numbers are growing daily, but as of July 28, 2014:

In Guinea – 460 cases, 339 deaths
Liberia – 329, 156 deaths
Nigeria – one case, one death
Sierra Leone – 533 cases, 233 deaths
There has been an approximate 40% survival rate.

To respond to the medical crisis, aid workers from Doctors Without Borders, containing volunteers from all over the world, entered infected areas to treat victims and help contain the disease.

Earlier in July, Patrick Sawyer, a government official in the Liberian Ministry of Finance, died at a Nigerian hospital. He was the first American to die in what health officials refer to as “the deadliest Ebola outbreak in history.”

Shortly after, Nancy Writebol, an American aid worker in Liberia, tested positive for Ebola she contracted while treating infected patients.

On July 26, Kent Brantly, medical director for Samaritan Purse’s Ebola Consolidated Case Management Center in Liberia, was infected with the virus while treating patients.

On July 29, Dr. Sheik Humarr Kahn, in charge of Ebola treatment at Kenema Government Hospital in Sierra Leone, died from complications of the disease.  The next day, The Peace Corps announced their decision to remove all volunteers from Liberia, Sierra Leone, and Guinea.

July 31, 2014 The Center for Disease Control went to Warning Level 3, advising all U.S. residents not to travel to Sierra Leone, Guinea, and Liberia unless absolutely necessary.

Where are they now?
On August 2, 2014, Dr. Kent Brantley, one of two living Americans infected with Ebola, was put aboard a specially equipped medical plane to leave Africa.  He landed at Dobbins Air Reserve Base in Georgia and then was driven by ambulance to Emory University Hospital, where he is being treated in quarantine.  The latest reports are that Dr. Brantley “seems to be improving.”

Nancy Writebol is expected to be flown back to the United States for treatment imminently.

What are the chances of spreading in the United States?
The high rate of international travel these days makes it a reality that other people inflicted with Ebola may come to the United States.  It’s important to note that Ebola does not spread through airborne transmission, so there is very little risk of respiratory infection just by being on the same plane or in the same airport as an infected person.

The CDC has set up an Ebola quarantine station at Los Angeles International airport, just as a precaution.

Is this the first time the Ebola virus has been in the U.S.?
Ebola has actually been seen in the United States before.  In 1989, macaque monkeys were imported from the Philippines and later found to be infected wit the Ebola virus.  They were quarantined in facilities in Texas and Virginia but managed to come in close contact with four humans.  The exposed people actually developed Ebola antibodies and never suffered symptoms, or had any health problems due to the virus.

What are the chances of a serious Ebola outbreak in the United States?
That is almost certain not to happen. Awareness, medical treatment, and medical technology are so far ahead of conditions in African outbreak areas that any cases are sure to isolated and safely contained. Epidemiologists would quickly track down people who exposed to the infection and make sure it can’t spread.

To cite an example, in May, the population of the Middle East was inflicted with hundreds of cases of the MERS virus.  Two infected people brought the virus to the United States but it never spread further.

Epidemiologist, doctors, and international medical professionals characterize the chance of even a small U.S. outbreak at “extremely unlikely.”