Bovine TB disguised by liver flukebovine tuberculosis (btb) could be spreading across Britain because the most widely used test for the disease is ineffective
when cattle are infected with a common liver parasite. The liver fluke Fasciola hepatica was known already to affect the standard skin test for btb,
but it was unclear whether the fluke stopped the disease developing or merely hid the symptoms.
A study published today in Nature Communications suggests that the latter is more likely, and that the effect is significant.
Researchers tested milk from dairy herds across England and Wales for antibodies against F. hepatica, an indication of infection,
If they assumed that a fluke infection inhibited btb detection, they achieved a closer match between the model and actual btb detection rates.
which is crucial to a genuine result in both the skin test and the second most common test for btb,
the interferon-Ã Â release assay (IGRA) blood test. Diana Williams an infectious disease specialist at the University of Liverpool, UK,
and an author of the paper, says the result helps explain why btb is still endemic across England and Wales."
questions whether the liver fluke hides infections.""Cattle carcasses are inspected in abattoirs and we would see evidence of TB in the slaughtered animals
because the fluke alters their immune response. A 2007 study supports this interpretation, showing that animals with preexisting tuberculosis had reduced sensitivity to the skin test
when they were infected with liver fluke2. The United states, Canada and Australia have eradicated btb, but Britain and Ireland have struggled to control it.
The disease costs the UK government around £100 million (US$158 million) a year. Control relies on testing cattle for btb before they are moved between farms;
and new infection sites crop up long distances from existing hotspots. Eradicating liver fluke could increase the sensitivity of the skin test
and allow better control of infected cattle, but this poses its own difficulties. Farmers can keep cattle away from damp fields that are home to the fluke s snail host,
In 2010 the European union (EU) banned most flukocide drugs because they leave toxic residues in milk.
The milk from cows that receive the remaining two allowed drugs is undrinkable for three days after treatment.
"The unreliability allows disease to remain undetected, and badgers are blamed when infected cows are found later,
Although more experiments are needed to confirm the precise interaction between flukes and the skin test, Dirk Werling,
an immunologist  at the Royal Veterinary College in Hatfield says there could be implications beyond cattle.
and btb causes 10%of human tuberculosis deaths in Africa.""We know that a similar immune mechanism exists in humans,
Liver fluke could also explain epidemiological mysteries, such as why btb has gained never a foothold in northwest England."
"If this can make people look more at epidemiology than politics, that would be marvellous
"Weed resistance is a game changer for agriculture in the same way that drug resistance has been a game changer for the health-care industry,
(although not the most toxic) in the defoliant Agent orange, used during the Vietnam war. Researchers are also wary of engaging in a continuing arms race with nature."
Malaria surge fearedthe war to bring malaria to heel has made slow but steady progress during the past decade,
But health officials fear that the spread of insecticide-resistant mosquitoes could bring about a resurgence of the disease.
says David Brandling-Bennett, the senior adviser for infectious diseases at the Bill & Melinda Gates Foundation in Seattle, Washington,
Such failures could reverse the recent drop in malaria mortality credited to insecticide spraying in the home and coating of bed nets,
the organization predicts, costing an extra US$30 Â million to $60 Â million annually for tests and medicines.
WHOTHE WHO report says that insecticide-resistant mosquitoes already inhabit 64 Â malaria-ridden countries (see map.
Health authorities in Somalia, Sudan and Turkey have reported also sporadic resistance to the two other classes of insecticides recommended by THE WHO for safe and effective household spraying:
To implement all of THE WHO s suggestions would cost $200 Â million on top of the $6 Â billion that THE WHO requested last year to fund existing malaria-control programmes.
director of the Global Malaria Programme at THE WHO, hopes that the report will draw more funds to the table as donors grasp the situation."
But the two largest players in malaria aid the Global Fund to Fight AIDS, Tuberculosis and Malaria,
and the US President s Malaria Initiative (PMI) have not yet pledged additional money to fight resistance.
Their spending on mosquito control is already high in 2009,39%of the Global Fund s malaria expenditures went towards insecticide-treated bed nets and household spraying,
In the meantime, health officials may be able to keep malaria at bay by swapping insecticides. The report notes that in Colombia
African ministers of health realize the need to manage resistance but can t do much without outside funds,
explains Maureen Coetzee, a medical entomologist at the University of the Witwatersrand in Johannesburg, South africa."
"In some countries, malaria control means one person sitting in one room, and he s lucky if he s got a chair,
As the United states first genetically engineered (GE) pigs with muscular dystrophy, the creatures could be used to test treatments for the disease.
But their utility will remain limited for the time being, while the US Food and Drug Administration (FDA) works out how to regulate them.
Exemplar Genetics which aims to sell GE pig models for use in academic and pharmaceutical laboratories, has bred so far about 275 Â pigs some with cystic fibrosis, others with heart disease, arrhythmia or cancer,
and now muscular dystrophy. Because pigs mimic these human diseases more closely than mice, they are desirable models for drug testing
and for studying the disease process. However, as the first company to seek approval for a disease model in a GE animal that could, in theory,
also be eaten, Exemplar is navigating a dimly lit regulatory path. In 2009, the company submitted its first application to the FDA for approval of its cystic fibrosis pig model."
"We don t really know what additional steps we need to do in order to get FDA approval for full commercialization,
says John Swart, president of Exemplar. Nevertheless, the company remains hopeful that its pigs will skirt the hardships that have befallen other GE animals in the pipeline.
As early as 1999, the FDA spoke about the promise of GE animals for both food and pharmaceutical purposes.
Ten years later, the agency created a framework to judge their safety. In 2009, it applied the guidelines in approving a GE goat that produces a blood-clotting drug in its milk.
Since then however, FDA approvals for two GE food animals have stalled: a salmon with a gene prompting faster growth,
and a hog engineered to excrete less-toxic manure. Members of Congress have voiced their fears about such frankenfish,
"GE pigs for medical models could move more quickly because there s a strong need for them in the medical community,
suggests David Edwards, director of animal biotechnology at the Biotechnology industry Organization based in WASHINGTON DC. Although animal-rights advocates may object to disease-model pigs,
Swart predicts that they will avoid intense public scrutiny because they aren meant t to be eaten.
Nonetheless, Swart is worried about the regulatory process for new animal drugs (NAD), which applies to all GE animals,
whether they re bred to produce food, drugs or, in Swart s case, disease.""The NAD process doesn t fit us real well,
he says. When Swart asked the FDA how to demonstrate the requirement that his products are safe for human consumption,
But Swart points out that diseases have variable symptoms.""We don t know much about these diseases,
which is need why we a model. While the pigs plod through the process one step at a time,
a handful of investigators at US universities have begun already to study how diseases develop in the transgenic animals.
Moreover, without approval, Exemplar cannot promote the pig models for drug testing based on what the researchers find.
Swart calls the wait worthwhile if Exemplar s pigs can help pharmaceutical companies to predict whether a drug will work."
"It s critical to figure out how to do this right with the FDA, he says
US$5-billion agricultural research portfolio unveiledthe CGIAR is a global network of research centres working to help foster food security, poverty reduction,
Biomedical careers The US National institutes of health on 14 Â June received two key reports on how to improve prospects for young biomedical scientists.
Unethical research A US court has dismissed a lawsuit by Guatemalan citizens against US officials over American researchers who intentionally infected Guatemalans with sexually transmitted diseases in the 1940s (see Nature 482
W. Greenblatt/Sygma/Corbisnobel chemist dies Organic chemist William Knowles (pictured), who shared the 2001 Nobel prize in Chemistry,
Mikovits theft case Chronic-fatigue-syndrome researcher Judy Mikovits is no longer facing criminal charges for stealing lab notebooks, computers and other material from her former employer, the Whittemore
Peterson Institute for Neuro-Immune Disease in Reno, Nevada. A Nevada district attorney dropped the charges last week,
although Mikovits (known for her now-retracted work linking chronic fatigue syndrome to a virus) still faces a civil suit from the institute.
Farmers say it is impossible to avoid growing GM soya because of contamination, and in April they won a challenge in the state of Rio grande do Sul,
2012) to show the scale of the health threat from mercury in Madre de dios. She found that in mining zones,
Mercury poisoning can cause vomiting and diarrhoea and, in more extreme cases, brain or kidney damage.
Despite the overwhelming evidence of harm Peruvians are divided still over the findings. Some march through Puerto Maldonado s main plaza shouting through megaphones that mercury is killing everyone,
whereas others are willing to drink the toxic liquid metal to prove it is safe.
non-governmental organizations have distributed retorts that can capture the toxic vapour. Two years ago, Peruvian engineer Carlos Villachica unveiled the ECO-100v, a US$4, 500 machine that uses water and jets of air to separate gold from sediments.
and mouth disease over the 50-year projected lifespan of the facility. The virus, which affects cattle
and mouth disease escaping, to 0. 11%over 50 years. Now, in its review of the revised assessment, released on 15 june,
and mouth disease, Manney sees zoonotic diseases those that can spread to humans as posing an even greater source of risk and uncertainty.
Manney s concern is echoed in the NAS's findings. From the review panel s perspective,"a valid scientific and technical risk analysis is quite possible for this facility.
"Very complex procedures are involved in dealing with zoonotic diseases, and there s no way to know what emerging diseases that the lab will be handling ten or twelve years from now and
what protocols might be required, he says.""The findings of this assessment will be incorporated into future plans
which diseases in large animals can be studied. Â"I think all of us recognize the need to advance our research
and our understanding of the diseases that affect animal populations in the United states and that could co-infect humans
and the kinds of mitigation strategies like vaccines that are said available Mark Thurmond, a committee member and veterinarian at the University of California at Davis. Deciding the ultimate fate of the NBAF falls to policy-makers,
and estimating them has been a headache for researchers. The uncertainties have been as large as 20%3. Guan s study is the first close, systematic look that is based on official energy figures.
Mapping identifies best targets for malaria preventiona slim but substantial swathe of Africa stands to gain from a new strategy in malaria control.
Preemptive treatment of children living in regions where the mosquito-transmitted disease is prevalent only during the rainy season could avert 11 million cases and 50,000 deaths a year.
The estimates are based on the world s first guidance on seasonal malaria chemoprevention, issued by the World health organization (WHO) in March.
and donors seeking to use anti-malaria drugs as prophylactics in African children, and the analysis pinpoints where the strategy would be most effective,
an infectious-disease physician at the London School of Hygiene and Tropical Medicine and co-author of the analysis,
director of THE WHO's Global Malaria Programme in Geneva.""But for policies with a number of requirements, we need these sorts of analyses to help policymakers chart the path forward.
malaria burden, predicted malaria seasonality and the efficacy of the drug combination sulphadoxine, pyrimethamine and amodiaquine (SP-AQ.
because sulphadoxine and pyrimethamine were used to treat the disease before the wormwood wonder drug artemisinin became the gold standard cure.
when drugs are taken as a prophylaxis, which is why THE WHO requires that people on SP-AQ take different medications
if they acquire the disease. At about US$1. 50 for up to four monthly treatments, a season's worth of SP-AQ would cost less than malarone or mefloquine,
the malaria-prevention pills that many tourists take when they visit these countries. At this low price
cost-benefit analyses suggest that SP-AQ would pay off if just one in every five children treated avoided the disease,
says Greenwood. from Ref 1areas with seasonal rainfall (orange-red) are most suitable for seasonal malaria chemoprevention.
One of the world s largest malaria-control organizations, the President s Malaria Initiative in WASHINGTON DC, may help carefully selected countries to implement the strategy,
says Bernard Nahlen, deputy coordinator of the initiative. That's because in addition to procuring the drugs,
Nahlen says, countries will need to pay health workers to distribute the medicine, and to monitor adverse effects.
In the 1980s he says, SP caused burn-like skin reactions in a tiny proportion of Westerners,
 Toxicity is one reason that African children have received never medicine to prevent the potentially lethal disease,
Another argument was based on the idea that African children are more vulnerable to severe malaria than adults
because they acquire a degree of immunity against the disease in youth. But little evidence supports the hypothesis that people who don't get malaria as a child will fare worse than those who do
if they get infected as adults, says Greenwood. Critics also argue that chemoprevention in Africa  is logistically
and financially impractical because malaria ravishes impoverished countries with feeble infrastructure. Debates about chemoprevention came to a halt when simpler modes of malaria prevention,
like bednets, hit the scene.""Once bed nets came along, everyone, including me, took their eyes off the ball
bed nets have halved the number of malaria cases, and seasonal chemoprevention has reduced the remaining cases  by about 80%.
%Seasonal chemoprevention would not be effective in some of the countries with the highest mortality from malaria,
because there the disease kills year-round and people rarely respond to SP-AQ. Newman therefore calls the strategy a"lower hanging fruit."
Philip Rosenthal, a malaria researcher at the University of California, San francisco, agrees, but stresses the need to explore strategies that could be used elsewhere, too.
"but I d counter that the international community has gotten millions of children antiretroviral therapy to treat HIV in the developing world,
Plant breeders are also working to improve the performance of maize under environmental stress using both conventional breeding and genetic modification.
Clinical trials The European commission has adopted proposals for new rules to replace its directive on clinical trials,
which set out how medical research is regulated across Europe. Many scientists criticize the decade-old directive for being excessively bureaucratic
and think that it has driven clinical research away from Europe. The reforms, formally proposed on 17 Â July,
Child study revamp  Leaders of the US National Children s Study have released a revised design for the ambitious effort to track influences on the health of 100,000 American children from before birth to age 21.
would enrol women from birthing hospitals across the country, creating a sample representative of the US population.
The US Congress may require a report from the Institute of Medicine before any changes are made to the current design.
Gene therapy Europe s drugs regulator has recommended for the first time a gene therapy for approval. Glybera, a treatment for a rare disease in which patients cannot produce enough lipoprotein lipase (an enzyme crucial for breaking down fat),
was backed by the European Medicines Agency s Committee for Medicinal Products for Human Use. The 20 july recommendation must also be endorsed by the European commission before the therapy becomes available
but a rejection would be unusual. The treatment is owned by uniqure, a company based in Amsterdam;
it has been tested on only 27 patients. See go. nature. com/ieekkp for more. Sequencing prize A US$10-million contest to sequence the genomes of 100 Â centenarians in 30 Â days has its first entrant:
Ion Torrent (a subsidiary of Life Technologies. The company, based in Guilford, Connecticut, said on 23 Â July that it would attempt to win the Archon Genomics X Prize,
Second obesity pill Just weeks after it approved its first weight-loss drug in 13 years,
the US Food and Drug Administration on 17 Â July gave the green light to a second obesity treatment:
although it carries a warning that those taking the drug should have monitored their heart rates. See go. nature. com/vtcifa for more.
But the case was reopened after two separate patents covering a way to determine drug dosage, from Prometheus Laboratories in San diego,
and genetically modifying plants to feed the world s population. go. nature. com/m128l22 August The governing board of the Cancer Prevention
George s"liver and kidneys appear to have some abnormalities, which the laboratories need to investigate in depth.
A lot of health problems are attributable to people not knowing about food. Of course other factors are involved, but at the end of the day, education is where it s at.
fuel, fiber, health, and environmental security through enhancing the pipeline of a well-educated and trained workforce.
and livestock provide ripe conditions for endemic zoonotic diseases to arise and spread, the study says.
and the United kingdom, are hotspots of emerging zoonotic infections, such as avian influenza.""Zoonoses present a major threat to human and animal health.
The burden for poor farmers is big, says Delia Grace, a veterinary epidemiologist at the International Livestock Research Institute (ILRI) in Nairobi,
and lead author of the study. The research team, which also included researchers from the Institute of Zoology in London,
and the Hanoi School of Public health in Vietnam, analysed 1, 000 surveys of disease covering 10 million people and 6 million animals.
but zoonotic disease are a major obstacle to this goal. For example, the study estimates that one in eight livestock animals in poor countries are affected by brucellosis,
reducing milk and meat production in cattle by 8%.In addition, 27%of livestock in developing countries showed signs of current
or past infection with bacterial food-borne disease. The latest research will help direct efforts
so that they can have the greatest impact in tackling disease and poverty, says Grace. The study builds on previous efforts to rank zoonotic diseases affecting the poor.
But those efforts relied on the opinions of experts and farmers and so were less objective than this study,
and adds to existing disease maps, which focused on emerging human diseases covering the years 1940-20042.
The new report includes data up to 2012, finding an additional 30 disease reports both before and since 2004.
It shows that the United states, the United kingdom and Australia are the key hotspots for emerging zoonotic diseases.
It is unclear why endemic diseases and emerging diseases follow different geographical patterns, says Grace,
a finding that conflicts with the idea held by many scientists that the crucible of disease emergence is biodiversity hotspots,
which tend to be found in developing countries.""We don t know why this is. It could be reporting and detection bias,
she says. Patchy surveillance and under-reporting is a huge problem in developing countries, where farmers fear they will lose their livestock without receiving compensation
if they report cases of disease.""Developing countries need help to develop reporting and surveillance networks and training for farmers and veterinarians in spotting
and reporting incidents of disease, says Bernard Vallat, director-general of the World organisation for Animal health (OIE) in Paris. The OIE is pushing for the World bank to establish a fund to compensate poor farmers in the case of large-scale disease outbreaks,
says Vallat.""It is for the global public good to have a worldwide reporting network that extends into remote areas,
NIH funding The US National institutes of health (NIH) will fund an initiative to help extramural researchers to diagnose mysterious maladies
a pot of money worth $545 million a year that the NIH director uses to make strategic investments.
Pharma fines Drug giant Glaxosmithkline will pay US$3 billion in fines for enormous health-care fraud.
is pleading guilty to promoting antidepressants for unapproved use, and to holding back data and making unsupported safety claims about its diabetes drug Avandia (rosiglitazone).
The settlement was announced last November, but legal documents detailing the guilty pleas were unsealed on 2 Â July.
Obesity pill The US Food and Drug Administration (FDA) approved a new weight-loss drug on 27 june
Belviq (lorcaserin), made by Arena Pharmaceuticals in San diego, California, suppresses food cravings by mimicking the effects of serotonin in the brain.
The agency rejected the drug two years ago because of safety concerns, but after additional tests it is now allowing Belviq s use in obese adults
and in overweight people who have related a weight health condition. See go. nature. com/vajfqe for more.
Pharma closure About 1, 000 Â jobs are to be lost with the closure of pharmaceutical company Roche s research site in Nutley
Roche said the 80-year-old base would cease operation by the end of 2013;
Amylin buy up Two pharmaceutical giants, Bristol-myers squibb and Astrazeneca, are teaming up to acquire the biotech firm Amylin,
based in San diego, California, for US$5. 3 Â billion (or $7 Â billion with existing contractual obligations).
Bristol-myers squibb, headquartered in New york city, is buying Amylin for its lucrative diabetes treatments. As part of the deal, announced on 29 Â June,
Amylin will receive $3. 4 Â billion from London-based Astrazeneca, and the two firms will share profits and losses from Amylin s drugs pipeline.
G. WOOD/AFP/GETTY IMAGESCARBON tax Australia introduced a carbon tax on 1 Â July, in
which the country s 300 biggest emitters of carbon dioxide will pay Aus$23 (US$23. 5) per tonne emitted.
Health act upheld The US Supreme court on 28 Â June voted narrowly in favour of upholding the Patient Protection
The law also includes provisions relevant to biomedical research, such as measures to speed up approval of generic versions of protein-based drugs.
See page 13 for more. UK science chief Mark Walport will be the United kingdom s next chief scientific adviser
Walport has been director of the Wellcome Trust, the United kingdom s largest biomedical charity, since 2003.
Pig fever sweeps across Russiarussian authorities have incinerated tens of thousands of pigs and closed roads in the past few weeks,
in an attempt to contain an emerging outbreak of African swine fever, a viral disease so lethal to the animals that it has been likened to Ebola.
The spread of the disease comes with a heavy economic toll last year, the Russian Federation lost 300,000 of the country s 19 million pigs to swine fever, at an estimated cost of about 7. 6  billion  roubles (US$240  million).
African swine fever was detected also for the first time in Ukraine in late July, and European and Asian countries are on the alert to deal with outbreaks that could cost their pork industries billions of dollars.
With no vaccine or cure for the disease, mass culls and vigilant hygiene offer the main defence.
Scientists first encountered African swine fever in the 1920s in domestic pigs in Kenya, where the vicious haemorrhagic fever felled nearly every animal infected.
The virus, which is carried also by warthogs and ticks without causing disease, is now endemic in much of Sub-saharan africa,
limiting pig farming there. It does not infect humans. In 1957, the virus jumped to Portugal after pigs near Lisbon s airport were fed infected human food scraps (the virus particles can survive meat curing processes.
It then hit Spain, and import of the region s ham including the coveted jam  n ibã rico was banned by many countries,
until the disease was eradicated in Spain and Portugal in the mid-1990s. The cases now flaring up in Russia,
says Linda Dixon, an expert on African swine fever at the Institute for Animal health in Pirbright, UK.
The disease quickly jumped to neighbouring Azerbaijan, Armenia and Chechnya, before fanning out across Russia (see Pig plague).
Source: C. Netherton/OIETHE recent spread of the virus means that the Ukrainian outbreak, now under control after authorities culled 208 pigs
To the east, the disease has been detected on the doorstep of Kazakhstan, which shares a long border with China,
The variety of ways in which African swine fever spreads only increases the uncertainty. Pigs can leave virus particles on transport vehicles,
or heat-sterilizing the food scraps can prevent disease transmission, says Dixon."I remember being taken to a little backyard farm near Nairobi,
The FAO warns that continued spread of African swine fever could be very costly Russia does not export its pork,
but trade restrictions could prove expensive for other countries where the disease becomes endemic.""If you are a small producer,
African swine fever was especially costly in South Ossetia during a 2008 conflict with Georgia,
While animal health officials focus on containing the spread of African swine fever, scientists believe that it should be possible to develop a vaccine to eradicate the disease.
The lucky few pigs that survive infection are rendered immune, so Dixon s lab and others are working to identify which of the virus s 175
or so genes trigger the immune system. In principle researchers could engineer these genes into the genome of a harmless virus to create a vaccine.
Alternatively, identifying and switching off the disease-causing genes in the virus could lead to an attenuated vaccine.
In the longer term, these options offer the best chance of halting the march of the virus,
I had a vaccine
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