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In this case study, students will have the opportunity to model the spread of tuberculosis and development of antibiotic resistance in a hypothetical prison environment. After reading a brief handout and viewing a short video, students play a simulation game by first identifying a group of prison inmates represented by index cards. The placement of the cards will influence how drug resistance spreads from one inmate to another. Using a dice roll to mimic random probability of infection and antibiotic misuse, students then track the development of resistance to four specific antibiotics, determined by selection of playing card suit. Opportunity for release or transfer on inmates from one facility to another introduces a further level of complexity, allowing students to study resistance spread. This activity was originally designed for a section of an upper-division biology course about antibiotic resistance, but it would also be appropriate for lower-division undergraduate and high school biology courses discussing antibiotic use.

A single genetic mutation causes resistance to DDT and pyrethroids (an insecticide class used in mosquito nets), new research concludes. With the continuing rise of resistance, the research is key as scientists say that this knowledge could help improve malaria control strategies. The researchers used a wide range of methods to narrow down how the resistance works, finding a single mutation in the GSTe2 gene, which makes insects break down DDT so it's no longer toxic. They have also shown that this gene makes insects resistant to pyrethroids raising the concern that GSTe2 gene could protect mosquitoes against the major insecticides used in public health.

Department of Defense researchers disclosed Thursday in a report placed online by the journal Antimicrobial Agents and Chemotherapy that a 49-year-old woman who sought medical care at a military-associated clinic in Pennsylvania last month, with what seemed to be a urinary tract infection, was carrying a strain of E. coli resistant to a wide range of drugs. That turned out to be because the organism carried 15 different genes conferring antibiotic resistance, clustered on two "mobile elements" that can move easily among bacteria. One element included the new, dreaded gene mcr-1.

When scientists first made contact with an isolated village of Yanomami hunter-gatherers in the remote mountains of the Amazon jungle of Venezuela in 2009, they marveled at the chance to study the health of people who had never been exposed to Western medicine or diets. But much to their surprise, these Yanomami's gut bacteria have already evolved a diverse array of antibiotic-resistance genes, according to a new study, even though these mountain people had never ingested antibiotics or animals raised with drugs. The find suggests that microbes have long evolved the capability to fight toxins, including antibiotics, and that preventing drug resistance may be harder than scientists thought.

This case study presents the story of Phil, an undergraduate majoring in biology, whose Russian cousin Dimitri has contracted tuberculosis (TB) from inmates at the prison where he works.  Phil learns that his cousin's failure to complete his antibiotic regimen likely contributed to the evolution of antibiotic-resistant TB in his body.  Phil consults with his friend Stacy, and together they try to understand Dimitri's condition by applying what they are learning in their genetics lab experiment about the role of random mutation in bacterial evolution (including the development of antibiotic resistance) through Luria- Delbrück fluctuation analysis. The same analysis includes calculation of the mutation rate, which Phil realizes is sufficient to cause MRSA and other antibiotic-resistant infections. This case study was originally developed for concurrent use in freshman/sophomore-level genetics, elementary statistics, and precalculus. However, it is also very appropriate for courses in introductory biology, evolutionary biology, and biostatistics. The teaching notes discuss various ways to run the case depending on the mathematics and biology background of students.

Using bacteriophages to deliver a specific CRISPR/Cas system into antibiotic-resistant bacteria can sensitize the microbes to the drugs, according to a study published this week (May 18) in PNAS.

7:23 video Are we entering the post-antibiotic era? Antibiotic-resistant bacteria are on the rise, with millions of infections reported every year and thousands of deaths. How does antibiotic resistance work? How did we get here? And what can we do in the future to make sure that papercuts don't spell a death sentence?

This interrupted case study for the flipped classroom applies evolutionary genetics research to human health. Students learn about a naturally occurring, but rare, allele of the CCR5 gene, CCR5-Δ32, which provides resistance to HIV. They use data from primary literature sources to predict and interpret worldwide patterns of CCR5-Δ32 frequency distribution. They then discuss how these allele frequency patterns may have been driven by selection imposed by various diseases or by other evolutionary mechanisms. Next, they test published data using Hardy-Weinberg equilibrium to examine if CCR5-Δ32 also provides genetic resistance to West Nile virus. Finally, they complete a jigsaw discussion of Nature News articles that report on how CCR5 research is being used to develop therapies to treat HIV. Originally written for the evolution portion of a yearlong biology series for undergraduate majors, the case is also appropriate for some non-majors biology courses or, with added complexity, upper-level evolution, genetics, or cell biology courses.

Discover natural selection as a mechanism of evolution with the Amoeba Sisters. This video also uncovers the relationship of natural selection and antibiotic resistance in bacteria.

ROME (Thomson Reuters Foundation) - If drug-resistant infections in people and animals are allowed to spread unchecked, some 28 million people will fall into poverty by 2050, and a century of progress in health will be reversed, the World Bank said on Monday. By 2050, annual global GDP would fall by at least 1.1 percent, although the loss could be as much as 3.8 percent - the equivalent of the 2008 financial crisis - the Bank said in a report released ahead of a high-level meeting on the issue at the United Nations in New York this week.

The threat of antibiotic resistance has become so dire that the United Nations General Assembly is holding a meeting to discuss it this month in New York City. Although WHO has been sounding the alarm on antibiotic resistance for years, this month's high-level U.N. meeting represents only the fourth time in the international body's history that its General Assembly-a global deliberative body that primarily grapples with issues like war and economics-has held a meeting to tackle a health topic.

"We risk being in a post-antibiotic world," said Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention, referring to the urinary tract infection of a 49-year-old Pennsylvania woman who had not traveled within the prior five months. Frieden, speaking at a National Press Club luncheon in Washington, D.C., said the bacteria was resistant to colistin, an antibiotic that is reserved for use against "nightmare bacteria."

Existing mouse models of lethal Ebola virus infection do not reproduce hallmark symptoms of Ebola hemorrhagic fever, neither delayed blood coagulation and disseminated intravascular coagulation, nor death from shock, thus restricting pathogenesis studies to non-human primates. Here we show that mice from the Collaborative Cross exhibit distinct disease phenotypes following mouse-adapted Ebola virus infection. Phenotypes range from complete resistance to lethal disease to severe hemorrhagic fever characterized by prolonged coagulation times and 100% mortality. Inflammatory signaling was associated with vascular permeability and endothelial activation, and resistance to lethal infection arose by induction of lymphocyte differentiation and cellular adhesion, likely mediated by the susceptibility allele Tek. These data indicate that genetic background determines susceptibility to Ebola hemorrhagic fever.

Malaria has long been a problem in Mali. But in 2006, the situation got worse: a malaria-carrying mosquito species named Anopheles coluzzii became increasingly resistant to common insecticides. Scientists searched for an explanation in its genes. Somehow, the species had acquired mutations that were previously only found in another species, Anopheles gambiae - despite the fact that these two species didn't usually mate with each other, and that their hybrids tended to die without producing offspring of their own, the mutations were identical.

If the lab technique works in the field, it could offer a new way of stopping the biting insects from spreading malaria to humans, they say. The scientists put a new "resistance" gene into the mosquito's own DNA, using a gene editing method called Crispr. And when the GM mosquitoes mated - their offspring inherited the same resistance, PNAS journal reports. In theory, if these mosquitoes bite people, they should not be able to pass on the parasite that causes malaria.

In 2012, the World Health Organisation classified colistin, the most widely used polymyxin, as being critically important for human health. But that didn't stop farmers around the world, especially in China, from using large quantities of colistin to fatten up pigs and chickens. Now Yi-Yun Liu at the South China Agricultural University in Guangzhou and colleagues have discovered the first known resistance gene for colistin that is able to move freely from one bacterium to another.

Discover natural selection as a mechanism of evolution with the Amoeba Sisters. This video also uncovers the relationship of natural selection and antibiotic resistance in bacteria.

In a creative stroke inspired by Hollywood wizardry, scientists from Harvard Medical School and Technion-Israel Institute of Technology have designed a simple way to observe how bacteria move as they become impervious to drugs. The experiments, described in the Sept. 9 issue of Science, are thought to provide the first large-scale glimpse of the maneuvers of bacteria as they encounter increasingly higher doses of antibiotics and adapt to survive - and thrive - in them.

Unprecedented multiple and extreme-level resistance is generated in mosquitoes found in the rice fields of Tiassalé in southern Côte d'Ivoire. A new study highlights the combination of stringently-replicated whole genome transcription profiling, in vivo transgenic gene expression and in vitro metabolism assays to identify and validate genes from the P450 detoxification enzyme superfamily which are highly expressed in the adult females from the area.

4:34 video Right now, you are inhabited by trillions of microorganisms. Many of these bacteria are harmless (or even helpful!), but there are a few strains of 'super bacteria' that are pretty nasty -- and they're growing resistant to our antibiotics. Why is this happening? Kevin Wu details the evolution of this problem that presents a big challenge for the future of medicine.