Monday, November 10, 2014

whether ebola transmitted diseases?

 ebolasuit

 How worried should I be about Ebola?
"Ebola is less contagious than most other infectious diseases we're familiar with", This is really important because part of what makes people so afraid of Ebola is that people infected with the disease can mistake it, in its early stages, for a normal flu, and, say, board a plane. But at that point, the disease just isn't very contagious yet.



In reality, Ebola is something different. About half of the people who contract Ebola die. The others return to a normal life after a months-long recovery that can include periods of hair loss, sensory changes, weakness, fatigue, headaches, and eye and liver inflammation.

As for the blood: While Ebola can cause people to hemorrhage, about half of Ebola sufferers ever experience bleeding.

More often than not, Ebola strikes like the worst and most humiliating flu you could imagine. People get the sweats, along with body aches and pains. They run a fever. Then they start vomiting and having uncontrollable diarrhea.

These symptoms can appear anywhere between two and 21 days after exposure to the virus. Sometimes, people go into shock. Sometimes, they bleed. Again, about half of those infected with the virus die, and this usually happens fairly quickly — within a few days or a couple of weeks of getting sick."direct contact" means these fluids need to get into your broken skin (such as a wound) or on to your mucous membranes (mouth, nose, eyes, vagina).

Ebola can also live on surfaces for a few hours, and in blood outside of the body, for up to a few days. So there is a risk of getting Ebola by touching a contaminated surface. But you'd then need to put your hands in your mouth or eyes. This is believed to be a less common mode of transmission. Again, most people seem to get infected through direct contact with bodily fluids.
"The virus has been able to live in semen for up to 82 days."


Theoretically, yes. But it's unlikely. This is what would need to happen for you to get Ebola in flight:

1) You can get the Ebola virus if you have "direct contact" with the bodily fluids of a sick person, including blood, saliva, breast milk, stool, sweat, semen, tears, vomit, and urine on  plane.

2) So you could get Ebola on a plane by kissing or sharing food with someone showing symptoms of Ebola. You could get it if that symptomatic person happens to bleed or vomit on you during flight, and those viral fluids hit your mouth or eyes. You could also get it if you happen to be seated next to a sick individual, who is sweating profusely, and you touch that virulent sweat to your face. At least this last scenario is unlikely, however. One of the Ebola discoverers, Peter Piot, said, "I wouldn't be worried to sit next to someone with Ebola virus on the Tube as long as they don't vomit on you or something. This is an infection that requires very close contact."

3) You can get Ebola through sex with an Ebola patient. So you could get Ebola on a plane if you join the Mile High Club with an Ebola-infected individual. The virus has been able to live in semen up to 82 days after a patient became symptomatic, which means sexual transmission — even with someone who has survived the disease for months — is possible.

4) You can get Ebola through contact with an infected surface. Though Ebola is easily killed with disinfectants like bleach, if it isn't caught, it can live outside the body on, say, an arm rest or table. In bodily fluids, like blood, the virus can survive for several days. So if someone with infectious Ebola gets his or her diseased bodily fluids on a surface that you touch — an airplane seat, for example — and then you put your hands in your mouth and eyes, you could get Ebola on an airplane.

5) This is a very unlikely situation, but: you can get the virus by eating wild animals infected with Ebola or coming into contact with their bodily fluids - on a plane. The fruit bat is believed to be the animal reservoir for Ebola, and when it's prepared for a meal or eaten raw, people get sick. So you could get Ebola in flight by bringing some under-cooked bat meat onto the aircraft and having it for supper.

From what we know right now, the causes of the biggest Ebola outbreak in history can be boiled down to these four things:

1) The virus turned up in West Africa this year for the first time ever. Not only did this mean officials there weren't on the lookout for it — they had never seen Ebola in these countries before — but it also delayed diagnosis of the problem by about three months, and allowed the virus to circulate widely before public-health measures were introduced to stop it.

2) The three West African countries most-affected are also some of the poorest in the world. They spend less than $100 per year per person on health care. They have few health professionals, and scarce personal protective equipment to protect them. They don't have robust disease surveillance networks in place. They have poor infrastructure to carry the sick around and get samples to labs for testing. They have few labs. The literacy rates are very low, meaning public-health information campaigns have been challenging. In the case of Liberia and Sierra Leone, their economies — and people's psyches — were only just recovering from years of brutal civil war, which left the population traumatized with little public trust in officials.

3) An accident of geography sparked an Ebola outbreak in a porous border region. The outbreak started in Guéckédou, a rainforest region in southeastern Guinea. Guéckédou also happens to share a very porous border with Sierra Leone and Liberia, where people travel in and out every day to go to the market or conduct business. Right now, epidemiologists believe travelers in the area quickly spread Ebola around, so when the situation was diagnosed in March, Ebola had already gone international. Suddenly three countries were battling the virus, and had to coordinate their responses. The usual methods for containing Ebola, like contact tracing, don't work in an epidemic of this size. At this scale, responding to Ebola becomes much more challenging and the disease difficult to stop.

4) The international response was slower than the virus. It took three months for health officials to identify Ebola as the cause of the epidemic, but another five months for the World Health Organization to declare a public health emergency, and two more months to mount a humanitarian response that still isn't fully in place and might not be for a few more weeks. Meanwhile, the caseload continues to grow exponentially. We still don't fully understand why the global response was so slow, but many observers say it was an avoidable tragedy that spiraled because international organizations failed to act.

If Ebola is not that contagious, why do people wear plastic space suits to care for Ebola patients?
There are a few reasons. The first one is simple: the virus is so deadly. Depending on the strain of Ebola, it can kill between 50 and 90 percent of those infected. And there is no cure on the market. Those suits are thought to be extra protection.

Second, unlike the civilian population, health workers who wear the suits are most at-risk for catching Ebola. They come into contact with all the infectious bodily fluids — vomit, blood, and feces — of sick people, often toward the end of patients' lives when their viral load has built up and they are most infectious.
Third, though all the science we have points to the fact that transmission must happen through contact with bodily fluids, science is never certain. Until this year, Ebola has been a rare disease and the research community is still getting the full picture of its transmission. So the suits cover workers from all potential contact they may have while caring for Ebola patients.
There is some controversy over the limits of these suits, however. Some say they are too cumbersome and, without proper training in how to put them on and take them off, rendered useless.


No comments:

Post a Comment