Ebola Outbreak in Uganda

There has been another outbreak of the deadly and highly infectious Ebola virus in western Uganda, in the district of Kibale. A report of July 29 about it appeared in the online Guardian newspaper

Ebola was first reported in 1976 in Congo and is named for the river where it was recognized, according to the Atlanta-based US Centers for Disease Control and Prevention 

As a CDC fact-sheet states states It “is a severe, often-fatal disease in humans and nonhuman primates (monkeys, gorillas, and chimpanzees”

It manifests itself as a haemorrhagic fever, is highly infectious and kills quickly. It is "characterized by fever, headache, joint and muscle aches, sore throat, and weakness, followed by diarrhoea, vomiting, and stomach pain. A rash, red eyes, hiccups and internal and external bleeding may be seen in some patients".

A chimp family in Kibale NP. Photo by one of 70 students, not sure who.

Those gorillas and chimpanzees, both of which have strong social groups, live closely together all year long. This undoubtedly helps the rapid dispersal of the virus, which is spread by close contact, not just with a victim, but also on communal food sources and other surfaces. So much so that Dr. Jane Goodall told me that one of her primate researching colleagues in the Congo basin had had her work utterly wiped out, not once, but twice, when entire families of habituated gorillas in her study died from the disease.

Of course grieving human family members also make close contact with their sick or deceased loved ones and hospital workers are very much at risk as there is no vaccine and no specific treatment.

Black and White Colobus monkeys

There are several things to think about, and perhaps the most important source of the outbreak has been skimmed over by either the newspaper or the investigators on site. In the July 29 report a brief mention is made of “contact” with monkeys. I’m sure there is more to it than that. About 8 years ago a case occurred in the most northwesterly part of Uganda when a man died of Ebola. He had been skinning out a black and white colobus monkey he had killed for consumption.

Red colobus in Kibale NP

However, it is by no means just great apes that can be involved.

There is a very strong and growing use of bushmeat in the area.  Traditionally Ugandans were averse to bushmeat, and in particular they did not eat primates. But over the last 15 or 20 years or so a large number of refugees have fled the events in the DRC and brought with them their hunting and bushmeat culture.  Of course relationships with locals have developed and so the consumption of bushmeat has risen steadily. 

For a really comprehensive review of the possible role of wildlife in Ebola epidemiology I would recommend an on-line article by a team from the Wildlife Conservation Society in the Emerging Health Threats Journal.

Canadian & Ugandan students on a forest trail

I made numerous trips to Kibale and other areas of Western Uganda between 2002 and 2009 when I took final year vet students there for one-month wildlife conservation externships. Our first field work took place in Kibale National Park

My students and I had what, in retrospect, were some very close calls. For one thing some of us handled monkeys. But primates may not be the only zoonotic source of the virus. 

There is a body of evidence that suggests that Egyptian fruit bats and even some other species may be carriers. They too are a major source of bushmeat and also certainly carry Marburg virus, which is very closely related to Ebola. So closely in fact that they are almost indistinguishable except by very detailed examination. The produce virtually the same symptoms and sufferers almost always die.

There is a fascinating cave in the Maramagambo forest in Queen Elizabeth NP that used to be part of the tourist circuit and we visited is several times. In this clip you can see some of us getting very close to the mouth of the cave in an attempt to see the resident python. He had surely found a perfect spot to hang out, practically a case of free lunches. The background noise is not a technical glitch. It is the sound of the chittering conversations of thousands of bats.

The cave is the roosting site for those thousand of bats.We all got quite close to them and lots of close-up photos were taken.

In the mid-2008 Dutch authorities confirmed that an unfortunate woman tourist who had had direct contact with a bat in the cave died of Marburg infection after she got back to Holland. 

In a report from the Center for Infectious Disease Research and Policy it was stated that three miners died of the same infection after bat contact in a different cave in another area of the country. 

Bats don't just roost in caves. Hundreds of them use the trees in the Makerere University grounds in Kampala and as the fast-falling dusk of the tropical evening approaches thousands of them can be seen swooping across the sky as they head out for their nightly feed.

I read about the Dutch woman through the wonderful ListServ of Promed and at once alerted my colleagues in Uganda. One of them, Dr. JB Nizeyi, was the chief in-country veterinarian for the Mountain Gorilla Veterinary Project and very much involved in our teaching. I understand that the cave in QEP has been closed to tourist ever since.

Bushmeat and the bushmeat trade is an emotional issue. I discussed it at some length in my book The Trouble With Lions. I feel that as Africa’s human population continues to increase the trade will expand. In some countries (Uganda, Kenya) the human population doubles about every 20 years. People get hungry. They kill wildlife for food and for revenge when their crops are destroyed or their cattle eaten by large predators. Of course that gets us into a whole other debate, about which I have posted before, but all of it is related.

Bushmeat smuggling from Africa

Linkhttp://www.silive.com/news/advance/index.ssf?/base/news/1252497614318590.xml&coll=1, http://www.nj.com/news/index.ssf/2009/05/seizure_of_bushmeat_from_lugga.html

In The Trouble With Lions I wrote about an unusual case of bushmeat smuggling in the USA. An immigrant woman from Liberia had been prosecuted for smuggling monkey parts. At her pretrial deposition in the Brooklyn federal court in Brooklyn she stated that she ate the bushmeat for religious purposes and

‘because monkey from the wildlife is a very smart animal’.

The case has moved along and a report by Frank Donnelly in the Staten Island Advance of Sept 9th states that the woman, named Mamie Manneh (or Jefferson) has pleaded guilty to smuggling illegal monkey parts. This happened after her church minister debunked her claim of bushmeat's religious significance. She will be sentenced on Nov 13th in Brooklyn Federal court.

One of the issues raised by the prosecution was the potential of disease spread from bushmeat. The prosecution veterinary expert mentioned Ebola, measles, tuberculosis, monkeypox and retroviruses similar to HIV but added that she was ‘she was unaware of any documented cases of such diseases being spread through consumer bushmeat.” It maybe that she was referring to such diseases occurring in the USA, but it is important to recognize that several of these diseases are known to have crossed into humans from bushmeat in other countries. The classic is the spread of HIV to humans from chimpanzees and sooty mangabeys on at least seven occasions in the last 100 years. Then there is the more recent finding of a gorilla derived form of HIV occurring in a human, which I recounted in this blog on August 4th under the title Gorillas and AIDS.

In a somewhat related case a Ugandan man was caught red-handed with bushmeat and fruit when his luggage was screened at Newark Liberty International Airport. Reporter Christopher N. Dela Cruz, writing in New Jersey Real-Time News, which is associated with the Star Ledger related that parts of antelope and cane rat were found along with fruit and other illegal commodities.

Lest anyone think that bushmeat smuggling is unusual, local authorities in Newark relate that this was the sixth seizure of bushmeat since October last year, totaling over 41 pounds. Last year, similar seizures weighed in at 88 pounds. Once again, and entirely appropriately, disease transmission to people from bushmeat was raised by federal authorities.

One of the slightly odd things about this report was that a picture accompanying the report showed a uniquely North American species, the pronghorn antelope. It seems possible that the newspaper lacked a picture of the most common antelope species in Uganda, the Uganda kob, (pictured here) which is often a target for poachers in Queen Elizabeth National Park and elsewhere.

In this case the man, whose name was not given, was fined $300 and released.

Bushmeat in Madagascar and Asia

Linkhttp://news.bbc.co.uk/earth/hi/earth_news/newsid_8210000/8210355.stm,
http://www.wildlifetrust.org/news/releases/flyingfoxes.shtml, http://www.scientificamerican.com/blog/60-second-science/post.cfm?id=worlds-largest-bat-being-hunted-int-2009-08-31, http://wdin.blogspot.com/

Two seemingly unrelated stories, one from the BBC and the other from the Wildlife Disease News Digest that came to me via their listserv once more showcase the subject of the bushmeat trade. The bottom line? Hunting is an old, old tradition and hungry people need to eat and will hunt the wild animals around them.

The first story comes from Madagascar and is headlined Lemurs butchered in Madagascar. Reporter Jody Bourton relates how the recent unrest and loss of law and order and “suspension of conservation aid” has led to wide-spread hunting and consumption of these already threatened or endangered animals. She sates

“The dead lemurs are sold to restaurant owners seeking to serve new delicacies.”

This may not be so much a story of hunger as of novelty.This picture shown in Jody’s report, taken by local non-government organisation Fanamby and released by Conservation International shows a basket of smoked lemurs available for sale.

Bourton concludes that

"The problem of illegal killing of lemurs in Madagascar will only be solved when authorities act and are empowered. Also, the big donor agencies, the United States and Europe need to reinstate funding for conservation activities there immediately, or the advances of the past 25 years will forever be lost."

The other story comes from Asia and concerns a different type of bushmeat. In this case it is the world’s largest bat, the so-called large flying fox that is being hunted. The story by John Platt is headlined World's largest bat being hunted into extinction

The study that Platt refers to was headed up by Dr. Jonathan H. Epstein of the Wildlife Trust in New York City. It was published in the August 25 online edition of the Journal of Applied Ecology.
In his report Epstein stated that in Malaysia alone, 22,000 bats are legally hunted every year, and an unknown number are also illegally killed.
He went further to say that

“this level of hunting is unsustainable
for the number of bats in the country and will decimate this ecologically important species."



The only real way to gauge the size of these animals is to look at the pictures (© 2009 Wildlife Trust) that appear on Dr. Epstein’s report. Keen observers will note that the man handling the bat is wearing protective clothing as well as a mask. I am sure that the garments are worn to protect not only the bat from human diseases, but vice versa. We do know that some really nasty viruses can be transmitted to people by Egyptian Fruit Bats in Africa. Check out Ebola and Marburg as a starter. I have not seen any similar reports about disease transmission from bats to humans in Asia, but who knows?

In this case the disappearance of the bats will have much wider implications than just one species. Epstein stated that the bats

"eat fruit and nectar and in doing so they drop seeds around and pollinate trees. So they are critical to the propagation of rainforest plants."


Marburg Virus and Fruit Bats

Linkhttp://www.reuters.com/article/healthNews/idUSL1166433320080711, http://www.sciencedaily.com/releases/2009/08/090801185900.htm, http://news.bbc.co.uk/2/hi/africa/6958015.stm

Just over a year ago, on July 11th 2008, there was a report on the important ListServ Promed Ahead and some other news outlets that told the terrifying story of a Dutch tourist who had died in Holland after being in contact with fruit bats in Uganda. She had visited the Maragambo Forest in Queen Elizabeth National Park, like thousands of others before her. These thousands included me, my wife and at least fifty of my students. We had gone there because there is a cave there that is home to thousands,
if not tens of thousands of Egyptian Fruit bats (Rousettus aegyptiacus) and it is mesmerizing to watch them flit in and out of the roost, never mind to see them clinging to the rock in their serried ranks.

There was an added bonus of attraction at the cave. A pair of African Fish Eagles had taken up residence just outside the entrance – grub to go as it were. Furthermore there was a resident python. In fact the last group of students had seen two pythons. So it is probable that a little biology 101 had been taking place. No exercise need for their packed lunches!



As you can imagine, the park authorities have closed the cave to tourists. The last thing they need is another catastrophe.

The Dutch doctors who cared for the dying patient and identified the cause of her death could not be absolutely certain where the virus came from, but the evidence has now mounted and seems conclusive.

The first suggestion of the link between fruit bats and Marburg, which is closely related to the better known Ebola virus, seems to have been made in 2007, as this BBC report shows.

Then came the recent (Aug 2nd 2009) report in ScienceDaily titled
'Ebola Cousin' Marburg Virus Isolated From African Fruit Bats. To quote:- “A paper published in the open-access science journal PLoS Pathogens provides new insight into the identity of the natural host of this deadly disease.”

As the authors of the PLoS article state, this brings the identification of the natural host of Ebola one step closer, as fruit bats are also strongly suspected in this disease. The first indication of this may have been in a 2005 paper in the prestigious journal Nature that can be found here.

There is one more important part of this chain. Fruit bats are a major source of bushmeat in the forests of central Africa. They are also pretty easy to catch when they return to their roosts during the day.

How many human forest dwellers have died of one of these deadly diseases and not even been noticed?