Fast, Cheap Testing for Tuberculosis? Soon It May Be Possible


Diagnosing a lung disease like tuberculosis with a urine test may seem illogical, but a group of American researchers is now a step closer to that goal.

Scientists at George Mason University have improved by at least 100 times the accuracy of testing for a sugar shed by tuberculosis bacteria, meaning that a simple dipstick urine test may soon become possible.

The researchers’ study was published last month in Science Translational Medicine.

Tuberculosis kills about 1.7 million people a year, according to the World Health Organization — more than are killed now by AIDS. While many people carry inactive bacteria, about 10 million fall ill annually and develop coughs that transmit the infection.

If they could be found and treated sooner, more would be cured and the spread would slow.

For decades, tuberculosis was diagnosed by chest X-rays, skin or blood tests, or by reading sputum samples under a microscope. But the W.H.O. has condemned skin and blood tests as inaccurate, X-rays detect only advanced damage, and microscopy requires trained pathologists.

Since 2010, detection has been revolutionized by GeneXpert machines, which take two hours to make the diagnosis. They not only find bacterial DNA in sputum but can tell if the strain is impervious to a common antibiotic, which suggests that the patient has multi-drug-resistant disease.

 

But the machines are expensive, even at discounts offered to poor countries, and it is hard for weak patients and children to hock up lung mucus. (Some clinics have sealed “cough rooms” where salt mist is blown deep into lungs to trigger coughing fits.) Urine is easier to obtain.

In tests on about 100 hospitalized Peruvians, half of whom were known to have tuberculosis, the new test proved about as accurate as GeneXpert machines, said Alessandra Luchini, a nanoparticle scientist at George Mason’s molecular biology center and co-author of the study. (The new test, however, does not measure drug resistance.)

The team hopes to adapt the new technique to clamp onto other tuberculosis-related molecules and come up “with a rapid test similar to a pregnancy test,” Dr. Luchini said.

Scientific Study of Surfer Butts Reveal Drug-Resistant Bacteria in the Oceans


Surfers are known to brave bad weather, dangerously sized waves, and even sharks, for the perfect ride. But, it seems another danger of surfing has been lying in plain sight all along: ocean waters are full of drug-resistant bacteria — and surfers are most at risk.

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In a study published this weekend in the journal Environmental International, a team of researchers from the University of Exeter found that regular surfers and bodyboarders are four times as likely as normal beach-goers to harbor bacteria with high likelihoods of antibiotic resistance. This is because surfers typically swallow ten times more seawater during a surf session than sea swimmers.

The cheekily named Beach Bums study, carried out with the help of UK charity Surfers Against Sewage compared rectal swabs from 300 participants and found that 9 percent of the surfers and bodyboarders (13 of 143) harbored drug-resistant E. coli in their systems, compared to just 3 percent of non-surfers (four of 130).

World Health Organization Anti-Microbial Resistance
The World Health Organization is concerned about drug resistance.

The World Health Organization has warned that widespread drug resistance may render antibiotics useless in the face of otherwise easily treatable bacterial infections, meaning that just as in the age before Penicillin, diseases like tuberculosis, pneumonia, blood poisoning, gonorrhea, food– and water-born illnesses as well as routine medical procedures that can lead to infection, including joint replacements and chemotherapy, could once again be fatal.

 Indeed, a 2016 report commissioned by the British government estimated that, by 2050, infections stemming from antimicrobial resistance could kill one person every three seconds.

Solutions to an impending drug resistance epidemic have largely focused on prescriptions and use, but there is an increasing focus on the role of the environment in transmitting drug-resistant bacteria strains. The Beach Bums study adds important insight into how sewage, run-off, and pollution that makes its way into the oceans spread the drug-resistant bacteria.

“We are not seeking to discourage people from spending time in the sea,” says Dr. Will Gaze of the University of Exeter Medical School, who supervised the research. “We now hope that our results will help policy-makers, beach managers, and water companies to make evidence-based decisions to improve water quality even further for the benefit of public health.”

Though the study’s purpose is not to alarm beachgoers — or surfers — Dr. Anne Leonard, who led the research, tells Inverse that the risk for anti-drug resistance may actually be lower in the United Kingdom, which “has invested a great deal of money in improving water quality at beaches, and 98 percent of English beaches are compliant with the European Bathing Water Directive. The risk of exposure to and colonization by antibiotic resistant bacteria in seawater might be greater in other countries which have fewer resources to spend on treating wastewater to improve water quality.”

For surfers on this side of the pond, check out the free app available for Apple and iOS, Swim Guide, for updated water quality information on 7,000 beaches in Canada and the U.S.

WHO issues ethics guidance to protect rights of TB patients


New tuberculosis (TB) ethics guidance, launched today by the World Health Organization (WHO), aims to help ensure that countries implementing the End TB Strategy adhere to sound ethical standards to protect the rights of all those affected.

TB, the world’s top infectious disease killer, claims 5 000 lives each day. The heaviest burden is carried by communities which already face socio-economic challenges: migrants, refugees, prisoners, ethnic minorities, miners and others working and living in risk-prone settings, and marginalized women, children and older people.

“TB strikes some of the world’s poorest people hardest,” said Dr Margaret Chan, WHO Director-General. “WHO is determined to overcome the stigma, discrimination, and other barriers that prevent so many of these people from obtaining the services they so badly need.”

Poverty, malnutrition, poor housing and sanitation, compounded by other risk factors such as HIV, tobacco, alcohol use and diabetes, can put people at heightened risk of TB and make it harder for them to access care. More than a third (4.3 million) of people with TB go undiagnosed or unreported, some receive no care at all and others access care of questionable quality.

The new WHO ethics guidance addresses contentious issues such as, the isolation of contagious patients, the rights of TB patients in prison, discriminatory policies against migrants affected by TB, among others. It emphasizes five key ethical obligations for governments, health workers, care providers, nongovernmental organizations, researchers and other stakeholders to:

  • provide patients with the social support they need to fulfil their responsibilities
  • refrain from isolating TB patients before exhausting all options to enable treatment adherence and only under very specific conditions
  • enable “key populations” to access same standard of care offered to other citizens
  • ensure all health workers operate in a safe environment
  • rapidly share evidence from research to inform national and global TB policy updates.

From guidance to action

Protecting human rights, ethics and equity are principles which underpin WHO’s End TB Strategy. But it is not easy to apply these principles on the ground. Patients, communities, health workers, policy makers and other stakeholders frequently face conflicts and ethical dilemmas. The current multidrug-resistant TB (MDR-TB) crisis and the health security threat it poses accentuate the situation even further.

“Only when evidence-based, effective interventions are informed by a sound ethical framework, and respect for human rights, will we be successful in reaching our ambitious goals of ending the TB epidemic and achieving universal health coverage. The SDG aspiration of leaving no one behind is centred on this,” said Dr Mario Raviglione, Director, WHO Global TB Programme.

“The guidance we have released today aims to identify the ethical predicaments faced in TB care delivery, and highlights key actions that can be taken to address them,” he added.

World TB Day is an opportunity to mobilize political and social commitment for further progress in efforts to end TB. This year, World TB Day signals new momentum at the highest levels with the announcement of the first ever Global Ministerial Conference on Ending TB, which will be held in Moscow in November 2017.

“The Global Ministerial Conference will highlight the need for an accelerated multisectoral response to TB in the context of the Sustainable Development Goals,” said Dr Ren Minghui, Assistant Director-General HIV/AIDS, Tuberculosis, Malaria and Neglected Tropical Diseases. “It will emphasize that global action against antimicrobial resistance must include optimized care, surveillance and research to address MDR-TB urgently”.

The Conference will inform the UN General Assembly high-level meeting on TB which will be held in 2018.

Source:WHO

Antibiotics resistance could kill 10 million a year by 2050


A British government-commissioned review has found that resistance to antibiotics could account for 10 million deaths a year and hit global gross domestic product by 2.0 to 3.5 percent by 2050

A British government-commissioned review has found that resistance to antibiotics could account for 10 million deaths a year and hit global gross domestic product by 2.0 to 3.5 percent by 2050

London (AFP) – A British government-commissioned review has found that resistance to antibiotics could account for 10 million deaths a year and hit global gross domestic product by 2.0 to 3.5 percent by 2050.

The Review on Antimicrobial Resistance said surgeries that have become widespread and low-risk thanks to antibiotics, such as caesarean sections, could become more dangerous without urgent action.

The review announced by British Prime Minister David Cameron was led by Jim O’Neill, former chief economist at US investment bank Goldman Sachs, and included British senior public health experts.

It found the region with the highest number of deaths attributable to antimicrobial resistance would be Asia with 4.7 million, followed by Africa with 4.1 million, while there would be 390,000 in Europe and 317,000 in the United States.

For comparison, the review estimated that the second-biggest killer, cancer, would account for 8.2 million deaths a year by 2050.

“The damaging effects of antimicrobial resistance are already manifesting themselves across the world,” the report said.

“Antimicrobial-resistant infections currently claim at least 50,000 lives each year across Europe and the US alone,” it added.

The calculations were based on existing studies by the think tank Rand Europe and the consultancy KPMG.

It warned drug resistance was not “a distant and abstract risk” and called for “a major intervention to avert what threatens to be a devastating burden on the world’s healthcare systems”.

The review emphasised the economic advantage of investment in tackling the problem early.

It said that three types of bacteria — the Klebsiella pneumonia, Escherichia coli (E. coli) and Staphylococcus aureus — were already showing signs of resistance to medicine.

Treatment of HIV, malaria and tuberculosis were broader public health issues in which resistance “is a concern”, the report said.

In the United States, antibiotic-resistant infections are associated with 23,000 deaths and two million illnesses each year.

The economic costs annually are as high as $20 billion (16 billion euros) in excess direct health care costs and $35 billion (28 billion euros) in lost productivity.

First new antibiotic in 30 years discovered in major breakthrough


Teixobactin pills: found to treat many common bacterial infections such as tuberculosis
The discovery of Teixobactin could pave the way for a new generation of antibiotics because of the way it was discovered.

The first new antibiotic to be discovered in nearly 30 years has been hailed as a ‘paradigm shift’ in the fight against the growing resistance to drugs.

Teixobactin has been found to treat many common bacterial infections such as tuberculosis, septicaemia and C. diff, and could be available within five years.

But more importantly it could pave the way for a new generation of antibiotics because of the way it was discovered.

 Scientists have always believed that the soil was teeming with new and potent antibiotics because bacteria have developed novel ways to fight off other microbes.

But 99 per cent of microbes will not grow in laboratory conditions leaving researchers frustrated that they could not get to the life-saving natural drugs.

Now a team from Northeastern University in Boston, Massachusetts, have discovered a way of using an electronic chip to grow the microbes in the soil and then isolate their antibiotic chemical compounds.

They discovered that one compound, Teixobactin, is highly effective against common bacterial infections Clostridium difficile, Mycobacterium tuberculous and Staphylococcus aureus.

Professor Kim Lewis, Director of the Antimicrobial Discovery Centre said: “Apart from the immediate implementation, there is also I think a paradigm shift in our minds because we have been operating on the basis that resistance development is inevitable and that we have to focus on introducing drugs faster than resistance

“Teixobactin shows how we can adopt an alternative strategy and develop compounds to which bacteria are not resistant.”

The first antibiotic Penicillin, was discovered by Alexander Fleming in 1928 and more than 100 compounds have been found since, but no new class has been found since 1987.

The lack of new drugs coupled with over-prescribing has led to bacteria becoming increasingly resistant to modern medicines.

Dame Sally Davies, the government’s Chief Medical Officer, said antibiotic resistant was ‘as big a risk of terrorism; and warned that Britain faced returning to a 19th century world where the smallest infection or operation could kill.

The World Health Oganisation has also classified antimicrobial resistance as a “serious threat’ to every region of the world which ‘has the potential to affect anyone, of any age, in any country”

However the new discovery offers hope that many new antibiotics could be found to fight bacterial infections.

Crucially, the scientists believe that bacteria will not become resistant to Teixobactin for at least 30 years because of its multiple methods of attack.

Testing on mice has already shown that the antibiotic works well at clearing infections, without side-effects. The team is now concentrating on upscaling production so that it could be tested in humans.

“Right now we can deliver a dose that cures mice and a variety of models of infection and we can deliver 10 mg per kg so it correlates well with human usage,” added Professor Lewis.

The breakthrough was heralded by scientists who said it could prove a ‘game-changer’ in the struggle against antimicrobial resistance.

Prof Laura Piddock, Professor of Microbiology at the University of Birmingham, said: “The screening tool developed by these researchers could be a ‘game changer’ for discovering new antibiotics as it allows compounds to be isolated from soil producing micro-organisms that do not grow under normal laboratory conditions.”

Prof Mark Woolhouse, Professor of Infectious Disease Epidemiology, from the University of Edinburgh added: “Any report of a new antibiotic is auspicious, but what most excites me about the paper is the tantalising prospect that this discovery is just the tip of the iceberg.

“Most antibiotics are natural products derived from microbes in the soil. The ones we have discovered so far come from a tiny subset of the rich diversity of microbes that live there.

“Lewis et al. have found a way to look for antibiotics in other kinds of microbe, part of the so-called microbial “dark matter” that is very difficult to study.”

Dr Angelika Gründling, Reader in Molecular Microbiology, Imperial College London said the discovery , ‘raises our hopes that new antibiotics can be brought to the clinics in the not too distant future.’

“The great hope is now that many more new antibiotics can be uncovered in a similar manner.”

Public Health England also welcomed the breakthrough.

“The rise in antibiotic resistance is a threat to modern healthcare as we know it so this discovery could potentially help to bridge the ever increasing gap between infections and the medicines we have available to treat them,” said Prof Neil Woodford, Head of Public Health England’s Antimicrobial Resistance and Healthcare Associated Infections Reference Unit.

Global Burden of TB Higher Than Thought


New, intensive efforts in recent years to improve collection and reporting of data on tuberculosis (TB) are ratcheting up concern over the epidemic, revealing there are nearly half a million more cases of the disease than previously estimated, the World Health Organization (WHO) said today.

WHO’s “Global Tuberculosis Report 2014” shows that 9 million people developed TB in 2013, and 1.5 million died.

 The report also notes that the mortality rate from TB is still falling and has dropped by 45% since 1990, whereas the number of people developing TB is declining by an average of 1.5% a year. An estimated 37 million lives have been saved through effective diagnosis and treatment of TB since 2000, the WHO said.

An estimated 1.1 million (13%) of the 9 million people who developed TB in 2013 were HIV-positive, according to the WHO, with the number of TB deaths among HIV-positive people falling from 540,000 in 2004 to 360,000 in 2013.

Multidrug-Resistant TB Crisis Continues

“Following a concerted effort by countries, by WHO and by multiple partners, investment in national surveys and routine surveillance efforts has substantially increased. This is providing us with much more and better data, bringing us closer and closer to understanding the true burden of tuberculosis,” Mario Raviglione, MD, director of the Global TB Programme, WHO, said in a prepared statement.

The report notes that the global health community has made “considerable” progress responding to multidrug-resistant tuberculosis (MDR-TB), yet it remains “far from sufficient.”

The MDR-TB “crisis” continues, the WHO said. Worldwide, about 3.5% of all people who developed TB in 2013 had MDR-TB. Some countries have “severe epidemics” of MDR-TB and “alarmingly low” treatment success rates, the report notes.

Furthermore, extensively drug-resistant TB has now been reported in 100 countries.

In 2009, the World Health Assembly called for universal access to diagnosis and treatment of MDR-TB, which contributed to a sharp increase in cases detected and treated. In 2013, 136,000 MDR-TB cases were detected, up from 52,825 in 2009, and 97,000 people were started on treatment, up from 30,500 in 2009.

“Although the number of patients treated has increased three-fold since 2009, at least 39,000 patients, diagnosed with this form of TB, were not being treated last year and globally only 48% of patients were cured,” the WHO said in a statement.

“The progress that has been made in combatting MDR-TB has been hard won and must be intensified. Containing and reversing the epidemic requires immediate and sustained efforts by all stakeholders,” Karin Weyer, PhD, WHO coordinator for laboratories, diagnostics, and drug resistance, said in the statement.

Increased Commitment Needed

“Improved diagnostic tools and access mean that we are detecting and treating more cases. But the gap between detecting and actually getting people started on treatment is widening and we urgently need increased commitment and funding to test and treat every case. In countries such as Estonia and Latvia, where there is universal access to rapid diagnostics and treatment, the number of MDR-TB cases has fallen significantly. This shows what can be achieved,” Dr Weyer said.

Currently, data on drug resistance are available for 144 countries, which collectively have 95% of the world’s population and TB cases. “This shows impressive progress; in the period 1994–1999, data were available for only 35 countries with 20% of the world’s population and 16% of the global TB burden,” the WHO said.

Levels of drug resistance among new cases are less than 3% in 108 (75%) of the 144 countries with drug resistance surveillance data. This includes almost all countries in the Region of the Americas, most countries in the African and Southeast Asia regions, most countries in Western Europe, and several countries in the Western Pacific Region.

Eastern European and central Asian countries have the highest levels of MDR-TB, reaching 35% of new cases and 75% of previously treated cases in some settings, the WHO said.

More than half of the global burden of MDR-TB is in three countries: India, China, and the Russian Federation.

The WHO said rapid molecular tests are now being incorporated into drug resistance surveillance programs, which are expanding to cover more drugs.

“To date, surveillance has focused primarily on resistance to rifampicin and isoniazid, the two most powerful first-line anti-TB drugs. Fluoroquinolones (FQs) and pyrazinamide (Z) are key drugs being tested as part of new TB and MDR-TB regimens. Understanding the background prevalence of resistance to these drugs is essential,” the WHO said.

In 2013, five countries started monitoring for resistance to FQs and Z (Azerbaijan, Bangladesh, Belarus, Pakistan, and South Africa), and surveillance will expand to more countries in 2015.

Preliminary results from the five countries show that resistance to rifampicin is often associated with resistance to Z. Resistance to ofloxacin (one of the FQs) is generally lower than rifampicin resistance, except in Asian countries in which FQs are extensively used, the WHO said.

Five Action Points

The agency said five priority actions are “crucial” to accelerate the response against the MDR-TB epidemic:

  • Prevent MDR-TB as a first priority.
  • Scale up rapid testing and detection of all MDR-TB cases.
  • Ensure prompt access to appropriate MDR-TB care, including adequate supplies of quality drugs and scaled-up country capacity to deliver services.
  • Prevent transmission of MDR-TB through appropriate infection control.
  • Underpin and sustain the MDR-TB response through high-level political commitment, strong leadership across multiple governmental sectors, ever-broadening partnerships, and financing for care and research.

“In addition to the serious under funding for research, US$ 8 billion a year is required for TB and MDR-TB prevention, diagnosis and treatment. Domestic and international financing needs to step up to prevent millions of unnecessary deaths,” said Katherine Floyd, WHO coordinator for TB monitoring and evaluation.

Dean Schraufnagel, MD, past president of the American Thoracic Society (ATS), stressed the need for more funding.

“While the overall mortality rate from TB has dropped by 45 percent since 1990, we note with concern the reported increase in TB deaths last year and the continued spread of [MDR-]TB. The WHO’s report also points out that 3 million people with TB are still being ‘missed,’ because they are not identified and treated for TB. The ATS reiterates its call to the international community to fully fund TB control and research and development programs,” he said in a prepared statement.

Diabetes epidemic threatens progress in tuberculosis control


A recent series published in The Lancet: Diabetes & Endocrinology suggests global efforts to control and eliminate tuberculosis could be hampered by the rapidly increasing rates of type 2 diabetes in low- and middle-income countries where tuberculosis is endemic.

Diseases can be attributed to diabetes, leading to more than 1 million cases a year, with more than 40% in China and India alone. Researchers warn that if diabetes rates continue to rise, the present downward trajectory of TB cases could have an 8% less reduction or more by 2035.

“These findings highlight the growing impact of diabetes on TB control in regions of the world where both diseases are prevalent,” Knut Lönroth, PhD, of the Global TB Programme at WHO in Geneva, said in a press release. “TB control is being undermined by the growing number of people with diabetes, which is expected to reach an astounding 592 million worldwide by 2035.”

According to the first paper in the series, during the past 3 years, a 52% increase in diabetes prevalence in the 22 highest TB burden countries could be associated with a 5% increase in diabetes-associated TB cases from 2010 to 2013.

“People with diabetes have a three times greater risk of contracting TB than people without diabetes, are four times more likely to relapse following treatment for TB, and are at twice the risk of dying during treatment than those without diabetes. These figures suggest we need to improve care for these patients at multiple levels,”Reinout van Crevel, PhD, series co-author and infectious disease specialist at Radboud University Medical Center in the Netherlands, said in the release.

However, according to the third paper, improving care for diabetes — using improved case definition, glucose control in patients with diabetes, and chemoprophylaxis in people with latent TB infection — could reduce TB cases by 15% or more by 2035.

“If we are to achieve the ambitious post-2015 global TB target to reduce TB incidence by 90% by 2035, increased efforts to diagnose and treat both TB and diabetes, especially in countries with a high burden of both diseases, will be crucial,” Lönroth said.

An editorial accompanying the series indicates that without adequate resources to combat diabetes, progress in reducing TB and other communicable diseases cannot be made.

“Importantly, the intersection between communicable diseases and [non-communicable diseases] should be used as a driver to strengthen health systems, to ensure that they can provide access to care with financial risk protection for all disorders, not just a select few,” researchers wrote. “Illness, death and disability do not recognize the divide between communicable and [non-communicable diseases], and nor should our delivery of health care.”

Seals and sea lions likely spread tuberculosis to humans .


Scientists who study tuberculosis have long debated its origins. New research shows that tuberculosis likely spread from humans in Africa to seals and sea lions that brought the disease to South America and transmitted it to Native people there before Europeans landed on the continent.
New research shows that tuberculosis likely spread from humans in Africa to seals and sea lions that brought the disease to South America.
Tuberculosis is one of the most persistent and deadliest infectious diseases in the world, killing one to two million people each year.
Scientists who study tuberculosis have long debated its origins. New research shows that tuberculosis likely spread from humans in Africa to seals and sea lions that brought the disease to South America and transmitted it to Native people there before Europeans landed on the continent.

The paper, “Pre-Columbian Mycobacterial Genomes Reveal Seals as a Source of New World Human Tuberculosis,” was published in Nature.

“We found that the tuberculosis strains were most closely related to strains in pinnipeds, which are seals and sea lions,” said researcher Anne Stone, Arizona State University School of Human Evolution and Social Change professor. Stone and Johannes Krause of the University of Tubingen in Germany are co-principal investigators on the project. Research teams from the Wellcome Trust Sanger Institute in the United Kingdom and the Swiss Institute for Tropical and Public Health were collaborators on the study.

“What we found was really surprising. The ancient strains are distinct from any known human-adapted tuberculosis strain,” Stone added.

Modern strains of tuberculosis currently circulating are most closely related to those found in Europe, and there was a complete replacement of the older strains when European disease reached the Americas during the age of exploration. Researchers found that genomes from humans in Peru dating from about 1,000 year ago provide unequivocal evidence that a member of the tuberculosis strain caused disease in South America before Europeans arrived, so the question among the scientists was, “What types of tuberculosis strains were present before contact?”

“The age of exploration is a time when people are moving really long distances around the world and coming into contact with others. It’s a time when a lot of disease spread,” Stone said. “This opens up a lot of new questions. It fits the bioarcheological evidence that shows the oldest evidence for tuberculosis in South America.”

“The connection to seals and sea lions is important to explain how a mammalian-adapted pathogen that evolved in Africa around 6,000 years ago could have reached Peru 5,000 years later,” Krause said.

In the study, researchers collected genetic samples from throughout the world and tested those for tuberculosis DNA while utilizing advances in technology during the past five years that enable more accurate genome capture from ancient samples. Of 76 DNA samples from New World pre- and post-contact sites, three from Peru around 750 to 1350 AD had tuberculosis DNA that could be used. The researchers then focused on these three samples and used array-based capture to obtain and map the complete genome.

These were compared against a larger dataset of modern genomes and animal strains. Research results showed the clear relationship to animal lineages, specifically seals and sea lions.

“Our results show unequivocal evidence of human infection caused by pinnipeds (sea lions and seals) in pre-Columbian South America. Within the past 2,500 years, the marine animals likely contracted the disease from an African host species and carried it across the ocean to coastal people in South America,” Stone said.

Africa has the most diversity among tuberculosis strains, implying that the pathogen likely originated from the continent and spread. After tuberculosis was established in South America, it may have moved north and infected people in North America before European settlers brought new strains in.

“We hypothesize that when the more virulent European strains came, they quickly replaced the pinniped strains,” Stone said.

“It was a surprise for all of us to find that tuberculosis, formerly believed to have spread around the world with ancient human migration events, is in fact a relatively young disease,” said Kelly Harkins, one of the study’s first authors and recent doctoral graduate from ASU’s Center for Bioarchaeological Research.

“A compelling prospect for future research will be to determine the relationship of these older forms to those currently circulating, and those isolated from other ancient remains,”said Kirsten Bos, postdoctoral fellow at the University of Tuebingen and another first author on the study.

Study implications include a greater understanding of the speed and process of adaptation when a disease changes hosts. This is especially of interest when considering diseases that are transmitted between species — MERS, SARS and HIV — and how these are spread, Stone added.

“Tuberculosis is a disease that is on the rise again worldwide. This study and further research will help us understand how the disease is transmitted and how the disease may evolve,” said Jane Buikstra, a collaborator on the study who identified tuberculosis in most of the cases utilized in the research. Buikstra is an ASU Regents’ Professor and Director of the Center for Bioarchaeological Research.


Story Source:

The above story is based on materials provided by Arizona State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kirsten I. Bos, Kelly M. Harkins, Alexander Herbig, Mireia Coscolla, Nico Weber, Iñaki Comas, Stephen A. Forrest, Josephine M. Bryant, Simon R. Harris, Verena J. Schuenemann, Tessa J. Campbell, Kerrtu Majander, Alicia K. Wilbur, Ricardo A. Guichon, Dawnie L. Wolfe Steadman, Della Collins Cook, Stefan Niemann, Marcel A. Behr, Martin Zumarraga, Ricardo Bastida, Daniel Huson, Kay Nieselt, Douglas Young, Julian Parkhill, Jane E. Buikstra, Sebastien Gagneux, Anne C. Stone, Johannes Krause. Pre-Columbian mycobacterial genomes reveal seals as a source of New World human tuberculosis. Nature, 2014; DOI:10.1038/nature13591

Rifamycin-Containing Regimens May Be Preferable in Latent Tuberculosis.


Although numerous regimens are effective for preventing active tuberculosis in patients with latent disease, those containing rifamycin are shorter and may be preferable for some patients, researchers say.

“Reassuringly, particularly in the light of past drug shortages, our analysis suggests that several currently recommended regimens are efficacious, including different lengths of isoniazid monotherapy and rifamycin-containing regimens,” said Dr. Helen R. Stagg from University College London.

“This therefore shifts clinical decision-making in the choice of regimens to adverse event profiles, interactions with concomitant medications, factors influencing patient adherence, and regimen cost,” she told Reuters Health by email.

Dr. Stagg and colleagues undertook a network meta-analysis of 53 trials to assess the benefits and harms of 15 regimens aimed at preventing active tuberculosis in patients with latent infection.

The regimens included isoniazid (INH) only, rifampicin (RMP), RMP-INH, RMP-INH-pyrazinamide (PZA), RMP-PZA, INH-rifapentine (RPT), and INH-rifabutin (RFB).

The RFB-INH regimens ranked highest in efficacy, but regimens using RMP for three to four months or RMP-INH for three to four months were also particularly efficacious, the researchers report in the Annals of Internal Medicine, online August 12.

INH regimens of varying lengths had overlapping credible intervals, but efficacy was highest for those lasting 12 months or longer.

Hepatotoxicity appeared to be lower with RMP alone, RMP-INH, and RPT-INH than with INH alone, whereas regimens containing PZA had higher toxicity than six months of INH or 12 weeks of RPT-INH.

RMP-PZA regimens had the highest risk for gastrointestinal adverse effects, and RMP regimens had the highest risk for central nervous system adverse effects.

“Comparison of different latent tuberculosis treatment regimens showed that therapies containing rifamycin for 3 months or more were efficacious at preventing active tuberculosis, potentially more so than isoniazid alone,” the researchers conclude. “Regimens containing rifamycin may be effective alternatives to isoniazid monotherapy.”

“There is clearly a need for shorter, less toxic regimens for latent tuberculosis treatment,” Dr. Stagg said. “More clinical trials are required to provide the evidence for such regimens. Additionally, better evidence is needed for treatment of latent infections in individuals exposed to people with drug-resistant tuberculosis.”

“Finally,” she added, “there is currently very little knowledge on good predictors for progression from latent tuberculosis infection to active disease — these will be a vital tool for future tuberculosis control, when incorporated into cheap, easy-to-use, clinical tests.”

TB vaccine ‘could help prevent MS’


MRI brain scan showing multiple sclerosis lesions


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An anti-tuberculosis vaccine could prevent multiple sclerosis, early research suggests.

A small-scale study by researchers at the Sapienza University of Rome has raised hopes that the disease can be warded off when early symptoms appear.

More research is needed before the BCG vaccine can be trialled on MS patients.

The MS Society said the chance to take a safe and effective preventative treatment after a first MS-like attack would be a huge step forward.

MS is a disease affecting nerves in the brain and spinal cord, causing problems with muscle movement, balance and vision.

Early signs include numbness, vision difficulties or problems with balance.

BCG vaccine

  • Bacillus Calmette-Guerin (BCG) is a live vaccine made up of a weakened strain of Mycobacterium bovisa bacterium that causes tuberculosis (TB) in cattle
  • The bacteria are altered so that they do not cause a TB infection, but stimulate the body’s immune system to make it resistant to the disease
  • The vaccine has existed for 80 years and is one of the most widely used of all current vaccines, reaching more than 80% of newborns and infants in countries where it is part of the national childhood immunisation programme

About half of people with a first episode of symptoms go on to develop MS within two years, while 10% have no more problems.

In the study, published in the journalNeurology, Italian researchers gave 33 people who had early signs of MS an injection of BCG vaccine.

The other 40 individuals in the study were given a placebo.

After five years, 30% of those who received the placebo had not developed MS, compared with 58% of those vaccinated.

“These results are promising, but much more research needs to be done to learn more about the safety and long-term effects of this live vaccine,” said study leader Dr Giovanni Ristori.

“Doctors should not start using this vaccine to treat MS or clinically isolated syndrome.”

Dr Susan Kohlhaas, head of biomedical research at the MS Society, said it was a small but interesting study.

“It’s really encouraging to see positive results from this small trial, but they’ll need validating in larger and longer-term studies before we know if the BCG vaccination can reduce the risk of someone developing MS.

“Ultimately, the chance to take a safe and effective preventative treatment after a first MS-like attack would be a huge step forward.”

The findings add weight to a theory that exposure to infections early in life might reduce the risk of diseases such as MS by stimulating the body’s immune system.

Dr Dennis Bourdette, of Oregon Health and Science University in Portland, US, said the research suggested “BCG could prove to be a ‘safe, inexpensive, and handy’ treatment for MS”.

He wrote in an accompanying editorial in Neurology: “The theory is that exposure to certain infections early in life might reduce the risk of these diseases by inducing the body to develop a protective immunity.”