Texans love all things armadillo. It is the state animal and Texas has become somewhat of a haven for hunting the small creature. In Louisiana and Texas, people hunt, skin and eat armadillos. Nothing exemplifies this all-things-armadillo attitude quite like the fact that barbecued armadillo and armadillo chili are popular delicacies in Texas. During the Great Depression Texans went as far as to stock their pantries with armadillos.

Every year, a significant number of people in southern United States walk into emergency rooms presenting with lesions of unknown origin. The lesions are quite clearly as a result of leprosy, but with some patients showing no history of foreign exposure (leprosy is not endemic to the United States) how they ended up with leprosy had always been somewhat of a mystery. Leprosy is rare in the United States, with only about 150 new cases reported each year — the majority of affected people lived or worked abroad in leprosy-endemic sub-tropical regions and may have acquired their disease there.

Leprosy is not highly infectious — caused by the slow-growing bacillus, Mycobacterium leprae, and transmitted via droplets from the nose and mouth of infected and untreated patients. It can cause nerve damage, leading to muscle weakness and atrophy, and permanent disabilities when left untreated.

It was in a lab in Baton Rouge, Louisiana that the case was first confirmed. Whole-genome resequencing of the leprosy bacteria from one wild armadillo and three US patients with leprosy revealed that the infective strains were identical. Infected armadillos had been reported across the southern United States, in Alabama, Arkansas, Louisiana, Mississippi, Texas, and Mexico, with several case reports have suggested that armadillos may be a source of the bacteria. The building body of evidence that these small animals act as a reservoir for the disease.

Even though leprosy is exceptionally rare in the United States, it seems exposure to armadillos in southern states is quite common. Authors publishing in the New England Journal of Medicine show that a single predominant strain is involved in most human and armadillo infections. Transmission is relatively easy, either direct or indirect, involving fomites. Although in this case the authors suppose it occurs most frequently through long-term direct contact with an infected host as the bacteria doesn’t last for long out in the environment.

Historically, leprosy had been hard to study. Very few animal models provided an adequate host for the disease. It grows vigorously in one animal — the armadillo, a fact discovered only in the 1970s at another federal laboratory in Baton Rouge. The nine-banded armadillo, Dasypus novemcinctus, is the only species of armadillo that occurs in North America, wondering north from Central America sometime during the early Pleistocene.

There was a time, before sophisticated experimental techniques, when the bacteria for leprosy couldn’t be cultured. Research, especially research that deals with combating infectious diseases relies heavily on being able to culture the infectious agent in a controlled environment. They tried experimentally to transmit the bacteria to other animals such as mice — but failed. Not being able to produce enough bacteria to be truly useful is always a setback for research. Add that to the fact that mice don’t live very long and human leprosy can be over the course of two decades.

Armadillo leprosy closely resembles the infection in humans — the lesions in its nerves was evidence of the armadillo as a suitable model animal.

Today, it is estimated that a third of the leprosy cases that arise each year in the United States almost certainly result from contact, in one form or another, with infected armadillos. Interspecies transfer of the disease is uncommon and inefficient, but within the armadillo species transmission is efficient.

What is becoming more and more evident is a complex problem — the ever increasing, incrementally advancing scourge of certain tropical diseases towards previously virgin areas, together with the fact that doctors have never seen these sorts of exotic diseases on a regular basis means there is frequent misdiagnosis. And as an estimated 70 percent of new emerging infectious diseases were known to have animal origins, perhaps it’s time to reflect and reframe the question.

The microbe that causes leprosy is a fragile one. It does not grow in laboratory petri dishes, and survives only a week or two in moist soils. Its presence in armadillos predates the fact we use it as a disease model. Ironically, armadillos would have acquired it from humans sometime in the last 400 to 500 years — sometime after colonization of the New World. Now they’re giving it back…

Image — source, source.

Since the summer of last year, the perennial talk of epidemics and pandemics has focused on a novel coronavirus. A virus that belongs to a diverse group of that affects many animal species — from bats to humans. At the time the public health risks were unknown. How many could eventually possibly become infected or die? How does the virus spread? Is Human to human transmission possible?

During the summer of 2012, in Jeddah, Saudi Arabia, the unknown coronavirus was isolated from the sputum of a patient with acute pneumonia and renal failure. To date, 55 laboratory-confirmed cases have been reported to the World Health Organisation. 31 individuals with laboratory-confirmed infection have died. Directly or indirectly most cases have been linked to four countries in the middle east; Saudi Arabia, Qatar, Jordan, and the United Arab Emirates. Now known as the Middle East Respiratory Syndrome Coronavirus (MERS-CoV), the exact scale and full parameters of a disease that the world is still understanding are slowly coming to the forefront.

Roughly two months ago a 73 year old man from Abu Dhabi died in a Munich hospital. He died on the 18th day of his infection of septic shock from the coronavirus infection he was suffering from. It is this patient, who was admitted to the Klinikum Schwabing in Munich in March, that is the subject of newly published research revealing more about the virus’ clinical features. Publishing in the Lancet, the research highlights the need for a therapeutic approach and that more data and research are needed. Little comprehensive clinical data on the new virus exists. In all, cases have been documented in Arabian Peninsula, Tunisia, Morocco, France, Italy, Germany, and the UK. Although one case in France turned out to be a false positive. Across all the documented and reported cases this is only the fifth patient for whom the virus’s progression and characteristics have been described in a medical journal.

A question early on had always been, is this the next SARS? In the spring and summer of 2003, the global outbreak of severe acute respiratory syndrome (SARS) caused more than 8000 probable or confirmed cases and 774 deaths in 25 countries across five continents. A health scare of pandemic proportions. And that is the new state of fear with every new mysterious infection. The new coronavirus (MERS-CoV) is one which Dr Margaret Chan, the Director General of the WHO, described as “my greatest concern right now.

We all know that mosquitoes spread malaria. What we never quite realise is that humans also spread malaria — and quite significantly. In some places, the spread of malaria is directly linked to the mass movements of human populations. The movements of infected humans seem to increase the dispersal of parasites beyond what would be possible by mosquitoes alone.

Fifty years ago, when we first tried to eradicate malaria, it failed — and among the main culprits (along with drug resistance and unsustainable funding) was listed movements of human populations. Historically, movements of infected people from areas where malaria was still endemic to areas where the disease had been eradicated led to a resurgence of the disease. As people and populations move, they can increase their risk for acquiring the disease, or increase the risk of transmitting it.

As always wars and civil unrest tend to favour disease transmission, and malaria is no different. During the 1980s in Angola, 15 years of continuous war had displaced hundreds of thousands of people. As a direct result, malaria moved from sixth to first place as the leading cause of mortality. This, simply because the capital city Luanda underwent an unprecedented population increase — and the malaria endemicity rose along with it. In a population that wasn’t ready for it.

The relationship between malaria transmission and population movement is undoubtedly complex. Population movements that either place people at risk for malaria or cause them to pose a risk to others cannot be stopped. But it seems now they can be tracked and we can mitigate for it.

In June of 2008, the movements of approximately 15 million people in Kenya were tracked using their mobile phones. Tracked, not by governments or refugee aid organisations, but tracked by researchers from the Harvard School of Public Health. During a 12 month period, every call or text made by each individual to one of 11,920 cell towers located within the boundaries of 692 settlements was logged and recorded.

Surveillance is a term that loses more and more of its meaning with every single advance in technology. Usually we picture more nefarious intents and purposes for tracking citizens. Within that year in Kenya, starting points and destinations of all 15 million individuals were tracked — giving each person a primary settlement to call home and mapping their movements in relation to malaria prevalence. Researchers determined where each person spent most of their time based on the location of the majority of their call and text records — this was their home base.

Mapping that onto malaria prevalence for the entire country allowed researchers to estimate and infer an individual’s probability of being infected and the probability that visitors to the settlement will become infected. Researchers built up what was essentially a parasite movement network.

There was some directionality to the net movements of people and parasites between settlements. Settlements can either be characterised as “source