I love viruses.
They fascinate me and I also think they are beautiful. Most have astonishing symmetry.
But Ebola? That s**t is scary. Ebola is one of the most lethal diseases on this planet. Depending on the strain, Ebola can kill up to 90% of infected people.
The world is having an Ebola outbreak. Right. This. Very. Minute. For the first time, Ebola is striking in West Africa. Previously the virus was limited to central Africa where it is endemic and causes outbreaks every 2-3 years.
At least 80 people have died out of a suspected 125 infections. The outbreak started in Guinea and has since spread to Sierra Leone, Liberia and Mali. While this number is small compared to outbreaks of other diseases, it is concerning because this is the first time an Ebola outbreak has spread between countries. Previous outbreaks were limited to the initial site of infection.
Theoretically Ebola should be easy to contain- it is only passed on through direct contact with bodily fluids of someone who is infected. It is not as easily transmitted as the flu, which can travel in air droplets and cause infection when it is breathed in.
But Guinea was completely unprepared for a disease that has never been seen in the country before. It took a month to diagnose the initial outbreak. Guinea’s public health system was already taxed with a measles outbreak and is struggling to deal with this new outbreak. Some of the infected are health care workers who didn’t know what they were working with until it was too late.
Humans are not the natural host of Ebola. African wild fruit bats are believed to be the natural reservoir for Ebola, although it is also easily found in chimpanzees, gorillas, porcupines and antelope.
Ebola is a filovirus. Rather then forming symmetrical virions, they form extended snake-like, filamentous virions. The virions house little genetic material; only 7 genes are expressed by Ebola.
Infections start with a sore throat, red eyes and maybe a rash. This is followed by fever, muscle pain, severe headache, vomiting, diarrhea, rash, kidney and liver failure, and in the worst cases, internal and external bleeding. Death occurs between 2 and 21 days after being infected.
As mentioned above, Ebola is spread through contact with bodily fluids; family members, health care workers and those preparing bodies for burial are the most at risk. Survivors remain infectious for a while. For example, the virus can be found in the semen of recovered male patients for up to 7 weeks post recovery.
There is no known cure or vaccine for Ebola.
The good news.
Currently, it is unlikely that Ebola will cause a pandemic (a world-wide epidemic). The virus strikes humans quickly and brutally; infected people are usually too sick to travel long distances (i.e. get on a plane). Because it kills people so quickly, there is less chance for spreading the disease. Once diagnosed, isolation and quarantine procedures can break the cycle of infection efficiently. Although a vaccine is still years away, the US and other countries are invested in finding a treatment.
If you are interested in learning more about Ebola and similar viruses, try reading the The Hot Zone by Richard Preston. It is a good, albeit scary, book.