Monday, September 14, 2015

What is Antibiotic Resistance?

The World Health Organisation (WHO) defines antibiotic resistance as the “resistance of a microorganism to an antimicrobial drug that was originally effective.” According to the Centers for Disease Control and Prevention, antibiotic resistance is “the ability of microbes to resist the effects of drugs – that is, the germs are not killed, and their growth is not stopped,” adding that infections “with resistant organisms are difficult to treat, requiring costly and sometimes toxic alternatives.” Antibiotic resistance, which is specific to bacteria, is part of a broader phenomenon known as antimicrobial resistance. This includes bacteria, parasites, viruses and even fungi.

How is it caused?

Antibiotic resistance is part of a natural process that might best be thought of in terms of selection. In the presence of antibiotics (i.e. when an infected person or animal is put on a course of antibiotics), conditions will inevitably favour those organisms that are able to frustrate, counteract, or inhibit the effective operation of the drug. This can happen in various ways, although two of most common involve either the strengthening or addition of the bacterial protective membrane, or a process known as efflux, whereby the chemicals introduced into the organism are flushed out before they can be effective. Traits such as an additional protective membrane or enhance efflux can occur as part of so-called “erroneous replication” – in effect a process of mutation.

How does it spread?

The most important way in which antibiotic resistance spreads is through the process of replication. All replicates of a resistant bacterium are likely to inherit the trait that is the source of the resistance. This means that in a host environment where antibiotics are present, conditions will favour resistant bacteria and their replicates. Treatment in a situation like this is not only likely to be more expensive, but it will also generally take longer. This in turn means that patients will often be infectious for longer, meaning that there is a greater probability that the infection will spread to others.
Another way in which antibiotic resistance spreads was described by Jerry Wright (chemical biologist at McMaster University in Ontario, Canada) in a recent interview with the Guardian: “Bacteria are very promiscuous and the most shocking thing we’ve realised over the past 60 years is just how rapidly this gene sharing occurs. They often acquire these resistance genes in packages, giving them resistance to multiple antibiotics at the same time, and that’s a major problem in hospitals.” These packages – also known as plasmids – enable bacteria to actually trade these resistance traits among themselves, and thereby to spread them rapidly.

How does it affect us?

Widespread misuse of antibiotics, in healthcare and animal husbandry, is largely responsible for the pandemic proportions of this problem, but it is also a very natural consequence of any antibiotic use at all. Predictions as to the future impact of the global spread of antibiotic resistance are dire, with the WHO itself pointing to the possibility of what it calls “the post-antibiotic era,” where “common infections and minor injuries, which have been treatable for decades, can once again kill.” Some have even suggested that simple surgical procedures might be impossible within the next two decades due to the risk of infection. Antibiotic resistance already causes close to a million deaths annually across the globe, and that number is projected to increase tenfold by the middle of the century.

What can be done?

Understanding the scale of the problem is one of the most serious challenges in the struggle against antimicrobial resistance, with the CDC calling for increased surveillance at the state level. In many parts of the world, no such monitoring programs exist at all, which also means that the potential for under-reporting is vast.

Another potent tool would be the development of new antibiotics (antibiotic development has been in decline since the late eighties), or the resurrection of old ones which might be deployed in novel ways and combinations now that scientists better understand the way they work. There have also been sustained calls for better stewardship by healthcare workers, pharmacists and others to ensure that they prescribe antibiotics more selectively and educate patients about the risks involved in not finishing a course, taking prescriptions meant for others, stockpiling antibiotics for later use, etc…
Work is also needed in terms of detection and diagnostic tools. Monitoring of this problem is still very much in its infancy in terms of coordination, efficiency and cooperation at the international level.

Antibiotic Resistance in the Chobe River System

Dr Alexander and her team have established the presence of antibiotic resistant bacteria among wildlife populations in the Chobe region. As part of their ongoing research on this issue, they are now seeking to establish whether or not these resistant bacteria are to be found in the river itself and, if so, how they got there, how widespread they are and what antibiotics, exactly, they have developed resistance against. This is very much in line with the calls described above to improve global surveillance and monitoring of resistant microorganisms, and might indeed take things a step further by monitoring environmental levels of these dangerous pathogens. One of the interesting things about the mechanisms for spreading antibiotic resistance is the fact that the genetic traits that cause it may also have other consequences for the bacteria. These are thought of in terms of evolutionary costs or benefits - in effect, whether they contribute to increased or decreased fitness, whether they help or hinder the organism in its survivability. As bacteria pass on these traits through replication and by swapping plasmids, they also transfer these costs and benefits. This might indeed prove to be one of the "chinks" in their armour, and might prove useful as part of the increasingly unconventional approaches being taken to combat this looming threat in the scientific world, and gaining a better understanding of the way these processes work is therefore of the utmost importance. 

Useful Links:




Tuesday, September 8, 2015

The Myth of the "Pristine"

Recent debates in fields as diverse as conservation, ecology, atmospheric chemistry, and geology have often touched on issues related to a proposed new geological era called the Anthropocene. First coined by ecologist Eugene F. Stoermer in the 1980s, the idea has since been popularized by Paul Crutzen (atmospheric chemist), and, although it has not yet entered the official nomenclature, it has been steadily gaining currency as a description of the present state of our planet for the last decade or so. The general argument is as follows: man's influence on global natural systems is now so pervasive (from the atmosphere to the nitrogen cycle, mass extinctions, climate change, changes in the distribution of species, etc...) as to constitute a distinct geological epoch. There is no aspect of life on earth, in other words, that is not in some way affected by human activity, no matter how remote or removed it might seem. 

By implication, therefore, there are no longer any truly pristine wilderness areas on planet earth. Every nook and recess has now been conscripted by human modernity, and, resultantly, the natural has become inextricably entangled with the human. Dr Kathleen Alexander's Coupled Natural-Human Systems project takes this situation into account from the first; it is in some sense the underlying premise. The Chobe River system and all surrounding (read dependent) human and wildlife populations are assessed in precisely these terms: as interconnected and inseparable, theoretically and practically – the extent of their interconnectedness itself constituting what might be considered the primary concern of the project as a whole, particularly in areas such as disease transmission and antibiotic resistance.

As recent literature would seem to indicate, this state of affairs requires a reassessment of conservation goals - particularly in fields and activities related to the preservation and restoration of wilderness areas. An article by Kopf, Finlayson and Humphries suggests that the answer might be to abandon ideas of returning such areas to their historical "pristine" states - which are in any case not only difficult to adequately define, but often fail to take into account the manner in which these systems naturally change over time - and instead to focus on what they term "Anthropocene baselines". These are defined as "ecosystems or parts of biodiversity that cannot – or will not – be restored to historical conditions," and would take into account the “reality of the modern world: humans depend on natural resources and, in many cases, biodiversity is depleted or permanently altered - but may still be used sustainably.”

“[T]he traditional focus on the goal of wilderness protection,” as Minteer and Pine put it, “rests on a view of “pristine” nature that is simply no longer viable on a planet hurtling toward nine billion human inhabitants.” So there is no longer such a thing as “pristine” – if ever there was. Both of these essays – and a host of others – are collected as part of a broader project on American Conservation in the Anthropocene published this year as an anthology of letters and essays. Entitled “After Preservation: Saving American Nature in the Age of Humans,” it is available from the University of Chicago Press, and promises to survey an idea that has come to represent the zeitgeist international conservation efforts.

In effect this means taking stock of a “new normal”, and with an abundance of terms like “historical”, “traditional”, “modern” etc… it is perhaps not surprising that history is manifestly a part of these debates. So far, this aspect of the conversation has tended to centre around locating the start of the Anthropocene epoch. Intellectual movements like this one, which seek to radically distinguish themselves from previous currents of thought often find themselves drawn to questions of origins, and the potential for rupture inherent in the very idea of the Anthropocene has lent itself to precisely this kind of intellectual foray.

Less attention has been devoted to the idea of “pristine” wilderness, or the manner in which it is a product of a specific moment in human history. The word pristine itself has undergone a series of shifts in meaning in the past few hundred years. In the original Latin, pristinus, (and also the Middle French pristin) it meant simply “former” – referring to any previous state. In the 16th century, in English, it was endowed with an additional sense of the primitive and undeveloped – coinciding, perhaps, with Britain’s first stirrings towards the outside world. Pristine in the sense in which we understand it today, that is of the unsullied, the unspoilt, the spotless, actually dates from as recently as the late 1890’s, that is at the tail-end of global exploration and European territorial expansion, the height of the British Empire and the rise of the first truly global economy.

These changes in significance chart a rather different epochal progression. When Lady Anne Boleyn used the word in a letter in the year 1534 (“Restored to his pristine fredome”), it referred simply to a previous, original condition, not to something in any way new or untouched, and certainly not primitive or undeveloped. By 1899, when the word appeared in the Westminster Gazette, it carried with it a sense of the unspoilt – in this case, of unspoilt architectural beauty, and also a little of the political upheavals of the time (“This indignant Tory thinks that what would be pristinely beautiful as Dollis Hill would be newly ugly as Gladstone Park”). A pristine wilderness in the 16th century was therefore a very different thing from what it came to mean in the 20th, and the epistemic violence of this shift should not be underestimated. The key change – one best perhaps illustrated by the history of the Masai people – was one from a previous condition, in effect the journey back in time experienced and described by the explorers of antiquity encountering wild landscapes and less technologically sophisticated cultures, to an idea of pristine that completely excluded a permanent human presence. A pristine wilderness today – and strangely enough, from the late 19th century onwards – is a wilderness devoid of permanent human habitation.

In the early 1890’s, Italian forces landed in present-day Eritrea and commenced battle with their Somalian adversaries. They brought with them Indian cattle and in so doing triggered one of the worst epizootics in human history. The rinderpest outbreak of the final years of the 19th century would eventually kill millions of people and even greater numbers of cattle and wildlife. It would eventually reach as far south as the Cape of Good Hope, leaving a vast swathe a death and suffering in its wake. In fact, so devastating were the consequences of this disease for the Masai people that contemporary estimates indicated a two-thirds decrease in overall population.

As a result, the Masai herdsmen and their cattle all but disappeared from the Serengeti plains, leaving subsequent European visitors with the impression the area was just about uninhabited. A 1955 report by the Royal National Parks Department concluded that the Serengeti was “a glimpse into Africa as it was before the white man ever crossed its shores”, a statement which couldn’t be further from the truth, given the fact that the emptiness of the landscape resulted directly of European adventurism on the horn of Africa half a century before. Ignorant of this fact, Tanzania’s colonial administrators set about protecting this status quo with the establishment of several national parks, including the world renowned Serengeti National Park – an area devoid of Masai herdsmen to this day. The conflation of the separate ideas of previous conditions and the absence of humanity is quite clear in this case, and the full violence of the term “pristine” could hardly be better exemplified.

This sad history also illustrates the difficulty inherent in adequately defining the parameters of an historical benchmark. Snapshots are never sufficient in terms of incorporating natural processes of ecological change, and fall even further from the mark in terms of man’s historical impact on the world’s ecosystems. Little wonder, then, that the term “pristine” has fallen out of favour. The full historical impact of the term is perhaps yet to be fully addressed, but its absence from future ecological debates is nonetheless something to be celebrated.

The Chobe Region has something in common with the Masai Mara and the Serengeti in that it has also been inhabited by humans for millennia now. The term “pristine” makes absolutely no sense here – the system has been a coupled natural-human one for a very, very long time – so long that any gesture further back, any attempt to restore a previous condition would be patently absurd. Man’s impact on the region’s ecosystems, though, has changed dramatically, particularly over the course of the last century. Assessing the nature of these changes is imperative in terms of defining the kind of “Anthropocene baseline” described above – and this is about much more than simply counting and finding substitutes for regionally extinct species (of which there are, unfortunately, quite a few).

The Coupled Natural-Human Systems Project will go some way toward defining these interactions and affects. The Chobe River system itself is at the heart of this endeavour of course – as it is at the heart of the system as a whole as well as being a (if not the) major interface between the human and the natural in this part of the world. The spread of antibiotic resistance within this system and a broad analysis of water quality variations over time are both a part of this process. Both of these sets of data will contribute towards a fuller understanding of what the Chobe’s Anthropocene benchmark should actually look like for the simple reason that they both shed more light on the effects of man’s actions on the environment around him – most crucially in terms of what man is putting into it, unintentionally or not. The end of the “pristine” need not herald the end of the wild, and nor does it mean the abandonment of sustainably managed ecosystems or the formulation of forward-thinking environmental policy. This is the philosophy of Virginia Tech’s Alexander Lab.

Friday, August 21, 2015

Water Sampling and the health of the Chobe River System:

The Chobe River system is as complex and diverse as it is beautiful, and understanding the manner in which adjacent human populations affect this crucial regional artery is of the utmost importance for conservation, community health and sustainability. As part of Dr Kathleen Alexander's ongoing Coupled Human-Natural Systems project (conducted through a partnership between CARACAL and Virginia Tech and funded by the NSF), the Chobe River is regularly sampled by her team. These are some images captured during this week's sampling, during which the team collected data at 28 points along the river. 

A number of issues are at play here. Perhaps most crucial is the role played by antibiotic resistance. Dr Alexander recently published a paper on this issue (we posted a link to it here), and this has since been the subject of a number of articles (most recently on SciDev.Net and AChangingWorld ). The current water quality analysis follows on from the previous study by tracking antibiotic resistance in E-coli present in the river system, and samples are taken at each of the sample sites specifically to test for the presence of resistant colonies.

Of course this cannot be assessed in isolation - we also need to understand the manner in which the river flows and a whole host of other variables which might affect the presence and abundance of these bacteria in the water-column, including the presence of sediments, river-traffic, effluent drainage points, seasonal variation in water-levels, annual flood-surges, variations in temperature, and many more. 

In effect, then, this study is about much more than just antibiotic resistance. This, certainly, is one of the most important research outcomes, but this study also aims to measure the overall health of the Chobe River System and -by extension - all the people and ecosystems dependent upon it. 

Friday, July 31, 2015

National Science Foundation Article on Water Quality and Health:

Dr Kathleen Alexander's Coupled Natural Human Systems research program (conducted through a partnership between CARACAL and Virginia Tech, and funded by the National Science Foundation) features this week on the NSF's home page! The NSF is an independent US federal agency "created by Congress in 1950 to promote the progress of science; to advance the national health, prosperity, and welfare..." It is perhaps the most prestigious research organisation in the world, and has an annual operating budget of $7.3Bn! Click on the link below to read the NSF's full article on Dr Alexander's program, which is working on the interconnectedness of human and natural systems and the manner in which wildlife species provide clues as to the spread of antibiotic resistance in Africa and around the world:

Monday, February 23, 2015

Help Ethel the aardvark! | Kathleen Alexander's Fundraiser on CrowdRise

Help Ethel the aardvark! |  Fundraiser on CrowdRise


In January 2015, Ethel, the aardvark, was attacked by domestic dogs in the Chobe Enclave, Botswana. The community and the Department of Wildlife and National Parks rescued Ethel and brought her to CARACAL (our NGO in Botswana) for care. Unfortunately Ethel had suffered significant injuries from the attack and was transported down to Maun to undergo surgery for a broken leg. After a month of recovering from surgery she has returned to us here at CARACAL, however, she is still in poor health. While we can provide expert veterinary care for Ethel at CARACAL, we do not have the funds that are required for her treatment, care and future life with us. Ethel's veterinary bills from her surgery were expensive and the costs of her ongoing care and treatment are escalating. When Ethel recovers she will require a custom built nocturnal enclosure at CARACAL where she will become an important ambassador for her species.

We are hoping to raise $10,000 to cover these costs, but the more funds we can raise, the better we can build Ethel’s new home. With a larger enclosure we can accommodate other rescued nocturnal animals (such as the two bush babies living with us) and create a homely environment for Ethel and her friends.

Sunday, February 22, 2015

Project identifies widespread occurrence of leptospirosis in wildlife in Botswana - causing a disease of global importance

Leptospirosis is an enormous public health threat that affects predominately the poor. CARACAL and Virginia Tech are working hard to understand this problem. Dr. Alexander has been leading a program of study on this important disease and together with her post doctoral student, Dr. Sarah Jobbins, they have made important discoveries. Not only have they identified the presence of this pathogen in Botswana, but the widespread occurrence of infection among wildlife. Many questions remain - does this pathogen affect any other species? How does leptospirosis move across the landscape? Although leptospirosis has not been reported in Botswana in humans - does this disease impact people and we just miss it because there are so many other disease that present with fever? We are working hard to find out!

Friday, October 3, 2014

Our work in Northern Botswana is focused on understanding the interaction between the environment, humans, and animals including wildlife and the implications this has to infectious disease transmission dynamics. Our previous work on diarrheal disease identified critical relationships between the environment and human and animal health.

We have launched a new and exciting component of our research. With community project partners, we are looking at how sanitation can influence diarrheal disease. In particular, how fly densities might be influenced by environmental drivers and how, in turn, flies might influence human health.

The Conservation, Food, and Health Foundation ( is providing critical support to this important work.

Joseph Berger, (CC)

Our Wild World | VoiceAmerica™

Our Wild World | VoiceAmerica™

Dr. Alexander interviews with VoiceAmerica to discuss the Ebola outbreak in West Africa.

Friday, March 14, 2014

Alexander and Sanderson highlight critical elements of predator management in complex systems.

Monday, January 27, 2014

With Allee effects, life for the social carnivore is complicated - Online First - Springer

With Allee effects, life for the social carnivore is complicated - Online First - Springer

From small to large, social carnivores are under complex pressures. Our work on carnivores highlights the important interaction between infectious disease and group living species and Allee Effects. We must seek to engage complexity as it will determine the success of our management approaches for system health. Dr Sanderson and Dr. Jobbins (Post Doctoral Research Associates in Dr. Alexander's Lab) work together with Dr Alexander to try and understand the dynamics of infectious disease at the environmental- human-animal interface.

Assessing elephants in the region for infectious disease.
Understanding infectious disease dynamics accross a spectrum of animals both domestic and wildlife is central to our program. Information gleaned is integrated with our active research directed at understanding human behavior and its influence on animal behavior.

Our recent publication (see above) on carnivores and Allee Effects, highlights the importance of understanding the complexities across human, animal, and environmental systems.

Thursday, September 26, 2013

Here are a few of the 70 students in CARACALs  Kazungula Primary weekly Conservation Club. We teach them to respect and protect the environment with lessons, crafts, games, interactive activities, and countless bad jokes.  I tried to get a picture with one of them, and this is what happens. I adore my students! -Erica

Wednesday, September 18, 2013

Science Daily - Researchers Help People in Remote Africa Respond to Diarrheal Disease

Our new publication provides information on diarrheal disease which might provide important insight into this persistent public health threat in Africa.

Kathleen Alexander, associate professor of wildlife, and Mpho Ramotadima, community extension officer at the Center for African Resource: Animals, Communities and Land Use (CARACAL), check water quality at a public faucet in a Botswana village. Alexander conducts research through CARACAL, a nonprofit nongovernment organization she co-founded in Botswana. (Credit: Virginia Tech)

Wednesday, September 11, 2013

Mpho Ramatadima and Cysco Charlie play a key role in our research program. Here with Dr. Alexander - Mpho is contributing to our knowledge of how aggression over human waste can increase health threats to wildlife and also continues to monitor ecological aspects of our study banded mongoose troops in addition to his work with local communities. Cysco uses his unique skill base in animal tracking to identify where and why animals move across the landscape. This information is key to identifying how humans and animals are linked across the landscape and how our impacts can change the health of the system.

Saturday, September 7, 2013

Water quality work continued this field season with both graduate students and undergraduates working on the project. Here Tyler, a PhD graduate student,  and Greg, a Virginia Tech undergraduate, work on the Chobe River during the biweekly sampling of the water and sediment. This long-term study is designed to provide unique insight into the impacts and interactions of human medicated environmental modification and related water quality changes. Keep up the good work guys!!!
Our summer was busy!!! Hundreds of children arrived at the biodiversity center to learn about animals and the research CARACAL and Virignia Tech are conducting. The core component of any meaningful research is the inclusion of education and outreach. Here, Dr. Alexander presents to a school group excited to see the Center.

Saturday, July 27, 2013

Banded mongoose offer a unique model to evaluate the impact of human activity on the environment. In our study site, mongoose live closely with humans and are also impacted by their activities both in the form of behavioral change but also disease. Understanding the nature and consequences of these impacts will allow us to better understand how humans are linked to the environment and the feedback that occurs to both humans and animals.

Wednesday, May 15, 2013

Program research paper profiled on the home page of NSF

Jobbins, Sanderson, and Alexander have recently published a paper identifying the presence of a  public health threat in Botswana previously unidentified - read more at

Sarah Jobbin's (left) tests samples in the Botswana field laboratory. Human waste in these systems (below, left)  can be ubiquitous and can  influence contact between humans and wildlife and disease transmission in these systems.

Wednesday, May 8, 2013

CARACAL UNTAMED - Alexander Laboratory reaching out to assist Botswana

CARACAL UNTAMED - fundraising event and party night!

This amazing event and all the supporting materials were prepared by Claire Sanderson, a post doctoral associate on the NSF project! Way to go Claire!!! We need more people with your heart!

check out our event video 

Saturday, May 4, 2013

 Our program attempts to integrate research with outreach and education. Waste is an important threat to humans and animals in the system. Our educational program incorporates research results into action. Here, children in our conservation and education program participate in a trash pick up day! They had a wonderful time and also contribute to a culture of change where ecosystem function and service is identified and valued. We need to work to sustain those services and the health of the ecosystem, and ultimately the health of the  humans and animals that depend on and are affected by the ecosystem.

Dr. Alexander collects data and water samples from public taps serving the community in Northern Botswana. Water quality changes occur not only in river but at collection points. Waste and water around the tap attracts both domestic and wild animals to the area. Increased interaction between humans - wildlife - and waste has the potential to greatly transform the landscape change pathogen transmission potential and risk. As humans change the environment, these change come back to influence the health of animals and humans. Our recent work identified that the highest level of drug resistance in banded mongoose (above) occurred  in the Chobe National Park. Under this program, we are attempting to identify landscape features that promote exchange of microorganisms and the spread of antibiotic resistance. Where are the linkages between humans and their natural environment?

Wednesday, May 1, 2013

Wild Animals Found Resistant to Antibiotics- project publication

Wild Animals Found Resistant to Antibiotics
A journalist assesses the work of our team and the implications to human and animal health. You can download this paper at

Friday, April 19, 2013

 At the an environmental fair, CARACAL staff use the animal collection to provide hands-on experiences of nature for the community in the study area. Even the elderly joined in and experienced the un-experienced!

Stefanie, a CARACAL staff member, climbs into the fun!

Kennedy, A CARACAL staff member, encourages everyone to try and touch a snake - no mean feat in Africa!!!

Experiencing nature and learning about its wonders in a safe environment provides the opportunity for communities to develop an appreciation of resources value that is identified at a personal level - a key to developing improved stewardship.