Sunday, August 31, 2008

Human Tuberculosis in wildlife

I picked up this interesting item on the Wildlife Disease Digest listserve ( of today's date. They run a blog (here) that covers many topics, and this one caught my eye. It concerns a recent article in the Times of South Africa has highlighted a problem that is likely to get worse as human populations expand and wild animals become more and more crowded and pressurized by people. The headline reads Human TB Strain Jumps To Animals and the key sentence reads “The human strain of the disease has been found in springbok, mongooses, baboons, chimpanzees and, most recently, a Maltese poodle." (Note the incorrect use of the plural mongooses, with the extra "s") The full story can be found here.

Of course this article builds upon scientific reports from authors working in other regions, most notably Botswana and South Africa, where the human form of the disease, caused by Mycobacterium tuberculosis has been found in both banded mongoose and meerkats (aka suricates).

An important journal article published in the journal Emerging Infectious Diseases by Kathleen Alexander and her co-investigators that describes the situation can be found here. Simply put, the animals had probably been exposed to the human form of tuberculosis at rubbish tips, or by investigating sputum that passers by had spat on to the ground. As Tb is the world’s most important infectious disease, and appears to manifest itself even more rapidly than before when a person is infected with HIV/AIDS, the risk to the animals is hugely increased.

We have seen examples of this self-same situation in Uganda, where, I had taken students from the Western College of Veterinary Medicine in 2003. The trip was the first in what has become an annual rotation for final year students enrolled in the college, and it is called the “African Wildlife Experience.” (you can find out more about at the 2007 and 2008 students blogs here.) Our goal is to link closely with students and faculty of the Makerere University Veterinary school, specifically the Department of Wildlife and Animal Resource Management (aka WARM).

In 2003 we saw a severely emaciated warthog (seen here) at Mweya, in Queen Elizabeth National park, and Ugandan faculty member Dr. Ludwig Siefert obtained permission to immobilize it and carry out a necropsy. We all saw lesions in liver and lung that looked very much like Tb, just like these small white spots in the liver, but to date we have had no confirmation of culture results.

The connections to human and other animal activity are interesting and convoluted. The warthogs in and around the lodge and backpacker’s hostel are totally habituated and can be found rooting in the garbage at any time – witness these two photos. Not only are they habituated to humans, but they have an amazing symbiotic relationship with banded mongoose, the same species that has been diagnosed with Tb in Botswana.

As this photo shows, the mongoose will clamber all over a warthog, appearing to search for food goodies that may range from ticks to skin scraps and who-knows-what else. Warthogs will lie down and solicit attention as soon as they see a mongoose.

Most alarming has been the recent finding in the park of an elephant that had lesions resembling Tb. We are going to Uganda again in February, and will hope to learn more. I wonder if the elephant is the bottle-raised Maria, seen here near the hostel and very near a group of warthogs, that has been a more-or-less permanent resident of the area. In 2003 she tried her damndest to get into our rooms, convinced that the bananas unwisely stored there were for her. The only problem was that she could not get her 40 inch wide frame through the 30 inch wide doors. She did manage to drink the wash water that one of our students had so carefully collected.

Monday, August 18, 2008

The Plastic menace

A recent posting on the Wildlife Disease New Digest blog, which appears two or three times a week as a listserv item (here is the URL carries a series of quotes and pictures that highlight the world’s growing problem with plastics. Many brief reports on the blog carry links to full stories on many subjects. The plastic one can be seen here. It opens with a quote from The National Geographic News of Sept 2003 that carries this blunt message:- Data released by the United States Environmental Protection Agency shows that somewhere between 500 billion and a trillion plastics bags are consumed worldwide each year.

The posting goes on to quote Jared Blumenfeld, Director of San Francisco’s Department of the Environment and states that There’s harsh economics behind bag recycling: It costs $4000 to process and recycle 1ton of plastic bags, which can then be sold on the commodities market for $32.

These quotes are followed by numerous grim pictures of plastic clogging up our cities and killing untold numbers of wild creatures in many ways.

Of course the authors do their best to offer a solution, pointing out that if only one person in five in the USA were to stop using plastic bags the reduction in waste would be absolutely huge – perhaps as many as 1,330,560,000,000 bags in our life time. They list several countries where plastic bag use has been banned – most notably in Africa, Rwanda has led the way

My own take on this problem appears in The Trouble With Lions in chapter 15. I quote:
We occasionally passed through villages whose chief characteristic was masses of thorn bushes highlighted by what have been euphemistically called Natal Poppies. The real reason for the colour is the accumulation of plastic bags, mainly black, which have blown from the ground where they have been carelessly dropped and have caught in the thorns. As the bags are virtually indestructible, the number of “poppies” continues to increase; moreover they seem to multiply of their own accord, as they gradually shred, so that one large bag becomes several small strips, all caught up in the thorns. An ugly sight.
In an interesting example of parallel evolution, Natal Poppies have sprung up all over Africa, and have become a common sight wherever one goes. A more generic name might be African Wild Flowers, as we have seen them in every African country that we have visited in the last fifteen years. Eventually they either shred themselves so small that they cannot hang on to the trees, or end up becoming the major visible form of garbage lining village streets. What a pity that they lack DNA and cannot propagate into useful bags every year or so. Since that time an attempt at control of this situation has been made, by making the giving away of plastic bags illegal in South Africa, but Markus (Hofmeyr) tells me that it has not had a noticeable effect on the flower crop.
The situation has hardly improved in the ten years since we learned the cynical nickname. Vast amounts of plastic clog up systems in most countries and recent reports indicate that even in Canada people are beginning to feel the grip of the man-made monster. In Uganda it is almost impossible to make a purchase without the item being stuffed into a small black plastic bag, called a Kavera. The bags end up in roadside garbage heaps and may be sporadically picked by an antiquated dump truck that drives off with its contents dribbling on to the road. The garbage piles are burnt from time to time, sending a plume of foul-smelling, choking toxic fumes into the air. It is hard to know which is worse.

An even newer posting on the Wildlife Disease New Digest blog concerns the effects of plastics in quite a different way. A report here suggests that the a breakdown chemical of plastics causes a fatal condition in lobsters called shell disease. Hans Laufer, the lead scientists on the study thinks that alkyphenols derived from hard plastics may be interfering with the ability of lobsters to develop tough shells.

It is difficult to see our way out of this one. A lot of people need to take a lot of action, or else our grandchildren – and their grandchildren - are going to inherit a world that we would not even recognize.

Uganda, Queen Elizabeth National park, Students

On Saturday Jo and I attended a lovely wedding near Brandon, Manitoba. It was special because the bride, Jeniifer Currah, aka Nif, had been with us in Uganda in 2003 and we have remained friends ever since. One of my favorite photos of her was taken in Queen Elizabeth National Park and shows her, cell phone glued to her right ear,chatting with her family back home in Canada while friend and class mate Jessica Paterson looks on and nibbles on a banana.

The photo was taken during a break from work, and after we had visited the village of Kasenyi, which you can just see in the background. We had been there after working on Uganda kob as part of a small research program into the status of brucellosis in the park, and it was at the village fish landing that we were mobbed by small children who wanted not only yo meet us, but to have our empty water bottles. It was Jessica who took this picture of a gaggle of kids around me and my camera as we shared a laugh about them appearing in video camera screen, where they had been watching themselves.

After she graduated Nif headed for Australia, where one of her uncles farms, and there she met and fell in love with Paul Wyman. They came to Canada for the wedding, which was held in the pretty prairie town of Minnedosa, only a few kilometres from the family farm, and the party was held in a Quonset on the farm.

Now we are further south, visiting our grandchildren in Minnesota and Sioux Falls. Back home next week.

Friday, August 8, 2008

Wildlife Disease Association, book marketing, Tsaatan, Mongolia

More book signings yesterday. Red Deer Alberta and now Lloydminster on the Alberta / Saskatchewan border, although I am about 1 km from the border itself in a shopping mall. Most annoying, the mall has no wireless Internet. Now that’s weird, at least it is in 2008, so I will have to wait until I get home to actually get this on to the page.

Apart from book gigs I have been reading the proceedings from the Wildlife Disease conference, just to see again what has been going on. One of the highlights of these gatherings, every year, is the full day devoted to student papers. Not only are the students highly motivated, because they are in competition mode for cash prizes and prestige, but because they show us oldies what is going on at the cutting edge of our discipline.

For instance there were several papers about reindeer, a favourite species of mine, and one I have worked on in Finland and Mongolia. Dr. Sophia Papageorgiou, a doctoral student at UC Davis has spent two work seasons in the high mountains of Mongolia, among the Tsaatan people and their reindeer, of whom you can read more here at the Itgel Foundation web site.

These pictures show the close relationship between the people and their animals. Sophia was studying one of the diseases that she is working with for her thesis. We had not met before, but I knew that she was there, and she knew that I too had been there. In my case it was three years of field seasons trying to see what is going on disease-wise with these fascinating animals. They are ridden, used as transport animals, milked and much loved.

Wednesday, August 6, 2008

Wildlife Disease Association, book marketing, The Trouble With Lions, Polar bear, bison

Writing from the forecourt of the Coles bookstore in the Edmonton City Centre Mall, where I am surrounded by copies of The Trouble With Lions and the big 2’ x 3’ poster that the U of Alberta Press made up for me. I’ve never tried this sort of selling before, but I’ve discovered that selling books can only really be done by the author getting out there.

This has been best exemplified over the last 3 days in Edmonton. I have been here attending the annual meeting of the Wildlife Disease Association, with its great website (here) the world’s premier group of like-minded scientists who concern themselves with wildlife in general and the diseases that affect them in particular.

The major themes of this year’s conference have been the overarching concern with global warming, and the more specific field of northern wildlife. Neither was any surprise, first because global warming is having a huge impact as animals move ever more northwards as the climate gets warmer and the habitat changes, allowing species to push at the edges. When I say species, most of us will think of things like white-tailed deer or moose, but as students of disease systems we have to remember that microscopic worms that can kill their hosts can also move into warmer climes because they can overwinter when conditions allow it.

The “poster child” species that has grabbed the attention of the media is the polar bear, and there is no doubt that they are charismatic, dangerous and already in trouble as the polar regions are warming faster than any other on earth. Over a period of about 12 years, starting in the early 1980’s I made several trips to the north, sometimes twice a year, to work on polar bears and wood bison. One publication from those days is about the development of a new drug for polar bear capture. You can find an abstract here but I'll have to put the pictures in when I get home. Home and now able to get at pics. Here's a favourite polar bear picture.

I'll also have to add pictures of our bison work, but a couple of abstracts of the original work are here, the first about the capture, the second about reproductive studies (pregnancy diagnosis). And here are some bison pictures.

With both species I was of course working with teams of biologists who were studying a range of issues centred on the ecology of the animals.

Who knows, one of these days I will put together a book about those trips, but right now it lies in 2nd place on the mental Rolodex of work as I have begun the research on my next big project, which I am calling, for now at least, The Virus and the Vaccine: How Cattle Plague Changed World History.