Today's post is inspired by the recently swirling news of the West African Ebola epidemic. So i dug a bit into it and decided to do an article on the whole issue. My primary (as in 99% primary :) ) sources of information were the Wikipedia articles Ebola Virus Disease and West Africa Ebola virus outbreak. The following is my condensed shorter version of the excruciatingly long Wikipedia entries.
The Ebola Virus disease was first discovered in 1976 in Zaire (now DRC). Mayinga N’Seke is documented as the index case, a fancy medical term for the first person that’s infected by an epidemic disease. She was a 22 year old nurse (who was apparently very fluent in English and was set to pursue an advanced nursing qualification in Europe) and contracted the disease whilst attending a nun (Sister Fermina) from Yambuku Mission Hospital. She died on 19 October; one of 318 other reported cases with an 88% death rate. She contracted the most dangerous of the “4 or 5” Viral strains – one that has gone through the following naming conventions- “Zaire virus Strain Mayinga” , “Zaire Ebola Virus” and is now just called Ebola Virus (EBOV).
Signs and Symptoms
The early stages (2 to 3 weeks – more commonly 8-10 days) of viral contraction are characterized by symptoms that can be mistaken for flu, malaria or cholera. They include fever, a sore throat, muscle pain and headaches. Nausea, vomiting and diarrhea follow, before the more characteristic (internal and/or external) hemorrhaging begins. Loss of appetite, chest pains, hiccups, shortness of breath and difficulty in swallowing may also be felt after infection. Bleeding will start typically 5-7 days after appearance of initial symptoms – internal bleeding presented as reddened eyes and bloody vomit, externally through wounds and openings – as the virus affects the blood’s clotting mechanisms. This blood loss and organ shut down is what causes the death, usually 7-16 days after first symptoms (typically 8-9) appear.
Transmission of the viral disease is primarily by contact with the body fluids of an infected person or animal (dead or alive) or of hospital equipment that has been used on someone with the virus. The virus stays in a survivor’s semen for close to 50 days and transmission through the air has not been documented or proven. This, coupled with the quick onset of symptoms, is why Ebola is considered a very low transmission rate disease. Dead persons are buried following documented disposal procedure because their bodies are still infectious. Animals that can be infected are primates (monkeys, gorilla’s etc.). Fruit bats have been shown not to be affected but can transfer and act as reservoirs of the virus (much like mosquitoes and malaria causing protozoa). The jump from fruit bats to humans typically follows a chain whereby fruit droppings are eaten by monkeys, which are then hunted for food, or come in contact with humans. In some parts of western Africa these bats are a delicacy and the jump may be more direct in such instances.
Diagnosis and previous epidemics
Ebola may be diagnosed by detecting for the presence of the virus in the blood, testing for its proteins or detecting the body’s antibodies. The disease has killed less than a thousand a year since 1976 when it was first discovered in the tropics of sub Saharan Africa. In August 2007 the disease killed 103 people in DRC in an epidemic which started after the funerals of 2 village chiefs and infected 217. Previously, 245 people had died just 320km from the source of the above mentioned outbreak. 149 cases which led to 37 deaths were reported over a 3 month period from 30 November 2007. December 2008 – January 2009 registered about 20 deaths from 45 reported cases. To bring this into perspective in 2012 alone malaria cases reported were totaling 207 million, 90% of which were in Africa. A child dies from malaria every minute and the same year, 460 000 didn't make it to their 5th birthday.
2014 West Africa Ebola epidemic
The current epidemic has been recorded as the worst Ebola epidemic in history. It has been traced back to a 2 year old child who died on 6 December 2013, in Guinea. It was first confirmed in March and has spread to Liberia, Nigeria, Sierra Leone and Nigeria, and by early April 157 suspected cases had been reported. As of 11 August the number had increased to 1975 reported cases and 1069 deaths. Since then , it has been designated a public health emergency of international concern, only the third in a line that includes the SWINE flu outbreak of 2009 and the 2014 resurgence of polio. This means signatories to the UN are mandated by law to follow strict epidemic control measures. Various international agencies have structured up to contain the spread of the epidemic.
Treatment and Containment
Ebola has no cure as yet. Needless to say, research has been ongoing and leads are promising. A test drug achieved 66% in the USA (1 of 3 died). In another investigation the blood of individuals who had survived the outbreak was used to cure others. Infertility treatments have achieved 90% treatment in mice tests. Due diligence is taken when doing laboratory and hospital procedure in epidemical areas and in research faculties. Hand washing is also advised in outbreak areas. Traditional burial rituals that involve contact with the corpse are discouraged. Quarantine also forces isolation and consequently reduces spread of the disease. Progress on vaccine development has also been promising.