We are getting swamped with queries about Ebola after the epdemic was reported in Eastern Democratic Republic of Congo. The Ebola virus has ever disturbed Uganda when it was confirmed in Gulu in 2000 and the Ugandan government managed to control this new epidemic of the Ebola virus.
What is Ebola? How infectious is it? How fatal? How can it be prevented?
What is it?
Ebola is one of a group of viruses called filo virus, which includes Marburg. Despite intensive search, no one has yet found out where it comes from. It affects and kills monkeys but they are not the carriers. Bats have been strongly suspected but as yet no one has found the virus in bats or their parasites. There have been a number of epidemics, each to a different strain of the virus, and named after the area affected: The biggest epidemics were Yambuku, in Zaire in 1976, Nzara and Maridi in Sudan in 76 and ’79 and the latest in Congo in 1995.
One very interesting finding is that some populations have a high incidence of antibodies to Ebola, which means they have had the disease and recovered. 1 or 2% in many parts of Congo, and an amazing 15% in one group of pygmies.
The incubation period is 5 to 7 days and symptoms start very suddenly. There is high fever and severe headache for a day then sore throat, so severe they cannot swallow saliva. This is followed by diarrhoea, coughing and vomiting. Within 3 days the patient is very ill indeed, hallucinating, toxic, and usually starting to bleed. Like many other heamorrhagic fevers, they bleed from everywhere. Teeth, eyes, nose, into the skin, into the intestines. They vomit black blood and pass bloody diarrhoea. They do not “bleed to death” as some people have reported, patients die from shock, as tissue fluid pours out into lungs, intestines etc. Most people die within 5 or 6 days.
Each epidemic has been different. With no care, fatality in some epidemics has been 90% or more. In other epidemics as low as 60%. As only Rabies has a greater fatality, i.e. 100%, and as Aids is still “unknown”, as not enough time has passed to see how long treated people survive, this makes it the second or third most fatal infection.
How is it spread?
So far every Ebola epidemic-affecting humans has been spread by direct contact with infective material.
The blood, sweat, urine, faeces, saliva, sputum are all loaded with virus and are infectious. It passes from the sick person to their carers, i.e. family members, nurses, doctors, lab technicians and funeral attendees. In the first epidemic, almost all cases got it from reused needles and syringes in the hospital. In Maridi also the main place of spread was the hospital, though many were infected after taking part in burials. There are probably small unknown mini epidemics all the time, where someone gets it, dies, spreads it to the family and other close contacts then the epidemic stops as everyone in contact is immune, dead or run away.
As yet there has been no evidence of spread by insects or airborne infection or from healthy victims in the incubation period. People from Yambuku came to Kinshasa while incubating Ebola and travelled in crowded matatus, ate in restaurants and moved around crowded streets right up to the time when they fell sick 5 to 7 days later. None of those contacts has ever got Ebola. All cases have been from direct contact with sick people or samples.
Interestingly in the Sudan epidemic there were no more cases after 4 generations, and in the Zaire none past 8 generations, i.e. passing from A to B to C to D but no “E” cases. It seems to burn itself out and become non-fatal after a few passages. This may explain the 1 to 2% sero positive rate in rural Congo.
There is however one scary scenario. The Ebola Reston outbreak in Virginia USA (the only one outside Africa). A large number of monkeys in a research facility in Reston died from Ebola. The virus spread from room to room by airborne infection, just like the cold or flu. The monkeys came from the Philippines and were handled by thousands of people in Manila, Amsterdam and JFK. No human was affected. Some of the handlers developed antibodies to Ebola Reston, but none of them were sick.
So there has been an epidemic of Ebola that was spread by airborne infection killed monkeys but was not harmful to humans. Therefore there is a possibility that in the future there may develop a “doomsday” strain of Ebola that is airborne and dangerous. It hasn’t happened yet.
How to prevent Ebola.
This is mostly simple, common sense hygiene. The Nzara Maridi epidemic was stopped by giving gloves to funeral handlers. The Zaire one died out when people stopped going to the hospital. Although the top lab workers are incredibly careful wearing Space suits in very highly secure environments, the experts in the field who visit villages in Ebola epidemics to take samples and control the spread often make do with masks and gloves and disinfectant. Most cases of infection of the CDC-type experts has been from needle stick injuries. In clinics and hospitals normal “barrier” nursing is effective, though “space suits” are usually given out when possible.
Ebola is not like Aids. Aids is much more scary because people are perfectly well and yet highly infectious for years. That normal looking man or woman with the wonderful eyes who is so interested in you has a 10% chance of giving you a fatal disease.
However Ebola is very fast. Infectious people are very ill and dead within a few days. It is dramatic. Most small epidemics probably die out before anyone knows it was there. In big outbreaks experts come in from around the world and the epidemic is quickly brought under control.
The general public is very unlikely indeed to be infected. The people who are infectious are very sick, not sitting next to you in a matatu or Doctor’s waiting room. There is no need to rush out of the room if someone casually mentions that he was in Gulu last week! I repeat, there have been no recorded cases of people getting Ebola from contact with the healthy while still in the incubation period. All cases have been from direct contact with sick people or their samples.
So if you are caring for someone who is sick, wear gloves, don’t let any blood, vomit or diarrhoea spill on you and wash like lady Macbeth if anything touches you.
Medical professionals will no doubt be given a crash course in barrier care and all the equipment necessary to prevent cross infection. Uganda in 2,000 is a very different place from rural Zaire in 1976. I am confident this epidemic will be brought under control very quickly indeed, and maybe the final mystery of where it comes from will be discovered.
Let’s hope that the Doomsday virus will always be a Hollywood phenomenon, not a Ugandan reality!
It’s there. So are the experts.
It will probably be over in a few weeks.
It’s not going to spread.
Be sensible with hygiene if you are caring for someone sick.