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After enduring more than 2 years criticism that included evidence of contamination and misrepresentation of data, a science paper that linked a mouse retrovirus to chronic fatigue syndrome (CFS) today received its last rites: Editor Chief Bruce Alberts issued a full retraction. 13 authors of the study in September signed a partial withdrawal after one of the three collaborating laboratories have found that contamination had marred his contribution, but they could not agree on the wording of the full retraction, Alberts therefore issued without approval. " Science has lost confidence in the report and the validity of its conclusions," wrote Alberts in an "editorial" unusual retraction, which appears in the December issue 23 Science . " it is Science 's opinion that a retraction signed by all the authors is not likely to come. "

researchers from the Whittemore Peterson Institute for Neuro-immune Disease (WPI) Reno, Nevada, conducted the controversial study, teaming with researchers from the National cancer Institute (NCI) and the Cleveland clinic in Ohio. as they reported online in the issue of October 8, 09 Science , they found evidence of a mouse virus called xenotropic virus related to murine leukemia virus (XMRV) in the blood of 67% of 101 CFS patients they analyzed. alarmingly 3.7% of controls were also tested positive, leading to fears that XMRV could be widely contaminate the blood supply in many countries.

Shortly after, researchers around the world began reporting that they could not find the virus in CFS patients. One group found that XMRV was probably created in laboratory experiments with mice that have an immortalized cell line to study prostate cancer and another showed that variants of this line had evolved more isolates XMRV, exactly the opposite of what would be expected if the mouse virus infected humans and really was subjected to immune pressure. The Department of Health and Human Services United States organized a study of nine laboratory to determine if the blood supply was at risk of XMRV or related mouse retroviruses. This so-called Group which included blood work WPI and NCI researchers who co-authored the original Science study using all the tests they chose, reported online September 22 in Science that no one could reliably detect the virus into previously positive samples from patients.

Alberts said the finding of the Blood Working Group was the straw that led Science to request the complete withdrawal. "The blood of study for me was dramatic evidence of poor science," Alberts said. "He gave us absolutely no confidence in the ability of large laboratories involved for testing. I find this extremely disturbing. "Francis Ruscetti NCI, a major retrovirologist and one of the co-authors, tried to coordinate with colleagues retraction, but a dispute arose over language that suggests some of the conclusions in the original document is still valid. "We tried to get all the authors agree, but he got endless," said Alberts. "the responsibility Science magazine in the scientific community is to make a strong statement that we do not believe that anything in this document may be invoked. "

WPI, who conducted the study with Ruscetti, said she and two of his lab assistants that contribute refused to sign the retraction. the day after the publication of the study of blood working Group Mikovits presented new data at a meeting of the CFS in Ottawa, Canada, which sought to show evidence of human gamma retrovirus XMRV-the family belongs to patients. It essentially argued that the original document focused too narrowly on a variant of XMRV. (It also showed a slide in the meeting that led to Science discovered that the original document had mislabeled image, which account in the fully retracted.) "We were confident of our data," Mikovits said science Insider, explaining why they wanted to include a line in the retraction who said they still trusted their data and conclusions. Ruscetti declined to comment about the complete withdrawal.

Mikovits was fired by WPI week after the Ottawa meeting for insubordination and accused in a civil lawsuit by his former employer of embezzling laboratory notebooks and computer data on his studies. Police at the University of Nevada, Reno, then filed a warrant for his arrest in connection with the allegedly stolen material, and was briefly imprisoned. Both civil and criminal cases are being considered.

Mikovits and Ruscetti currently participating in a pathogen coordinated MultiLab study sleuth Ian Lipkin at Columbia University in New York City that will look XMRV and related viruses in many more CFS patients that were analyzed in the work group study blood. Mikovits said the study of $ 2.3 million, funded by the National Institute of Allergy and Infectious Diseases of the United States, has also taken into account in the decision not to sign the full withdrawal. "We believe it is premature to do something before it's over," said Mikovits, who believes they will have results within two months.

Alberts strongly disagree. "I think they should cancel this study, "said Alberts." It's over. They can not do the tests, so what's the point? Why should he give a different result from that of the blood group study? Maybe retracting help us to scale back how much money they spent on it. It seems like an incredible waste. "

Researchers who have closely followed this saga and invested their own efforts to find XMRV in CFS patients congratulate Science to issue a full retraction." It is very sad, but the writing is on the wall for some time and the font size got bigger during the year, "said Jonathan Stoye retrovirologist the Medical Research Council in London, who co-authored an editorial science supporting the original document. John Coffin, a retrovirologist at Tufts University in Boston, who wrote an editorial with Stoye, said the full withdrawal could have happened much earlier. "It is a bit of a surprise that it took so long," said Coffin.

Science Editor Monica Bradford said the review authors still prefer to sign retractions. "He is the work of the authors and is a very clear signal to the scientific community that can not be other charges of the agenda, "said Bradford. Alberts said they had simply been" spun "by authors too often for too long. "If our editorial retraction contributes to ending the resources to go to this useless effort, I think we have made a contribution to the scientific community," he said.

See also :. lawyer Judy Mikovits discusses developments in his criminal case

Update, 3:35 p.m. Paper co-author Robert Silverman of the Lerner College Cleveland Clinic Medicine of Case Western Reserve University has sent this statement to science Insider:

I asked for a complete withdrawal of our results this summer after finding that blood samples were contaminated. I was in favor of a withdrawal from the entire paper at the time. I am pleased that the Journal has granted a retraction of the whole paper, and I agree with that decision.

last week, the National Institutes of Health (NIH) announced that research funding success rate, a closely watched indicator of how whose investigators are doing in the fight for funds, fell to a low in 2011: 18%. At first glance, the decline appears to be due to increased competition, as evidenced by a sharp increase in applications last year. But many other factors are involved, including budgetary decisions made years ago, said the head of the extramural NIH Sally Rockey.

The success rate is the number of grants funded divided by the applications considered. 18% success rate, announced by Rockey on his blog, is down 3% compared to 2010 and is slightly higher than a preliminary estimate from last fall. It continues a rate of about 30% success ten years ago when the NIH budget has been growing. Part of the explanation is that the denominator is greater: the investigators sent a record number of grant proposals for research at NIH 49592 last year, an increase of 8%.

But not the whole story, Rockey said in a blog post today. Much of the increase is explained by a 17% increase in proposals for a specific category of R21-short-term financing grants. The mainstay of most laboratories are the largest R01, individual grant conducted at the NIH initiative, for which the success rate slipped from 22% in 2010 to 18% in 2011. Applications were up 3% R01. Another reason for the slip rate of success is that the NIH funded grants R01 copmpeting less than in 2010. This is partly because the size of the average grant increased slightly because the NIH had less to spend on global R01 (its budget was cut 1% last year).

But the most important factor, accounting for 1.5% of the decline in success rates is that most of R01 money than usual has been attached to previous grants. Because most NIH grants last 3-5 years every price creates several years of future unfunded liabilities. The amount of money needed for these ongoing grants increased from $ 189 million in 2011, reports Rockey. "This shows how careful we have to manage our funds since funding decisions in a given year have implications for years on," she wrote. She displayed a graph showing how the share of R01 NIH money committed to ongoing grants fluctuates from year to year. In 2011 it jumped to 78%, the highest level in 4 years.

A careful observer NIH, Howard Garrison of the Federation of American Societies for Experimental Biology, said the management of the off-year commitment is a delicate balancing act for the agency. If NIH gets a generous increase in a year and does not fund more grants, "People like me go mad because money does not go in the street," he said. Yet if Congress reduced the budget of the NIH few years later and NIH's commitment has increased, "You're toast," and success rates plunge

Rockey bottom line. "The success rate is complicated and it is not enough of a single factor "that animates it, she said Science Insider. She added that the success rate does not reflect "the amount of science" NIH is funding. The funded researchers basin has remained relatively stable in recent years, she said.

Although the NIH has received a modest increase of 0.8% in 2012, the agency seems to be girding for a period of austerity. Review reports today that the continuous subsidies will receive no inflationary increase in 2012 and new rewards will not receive inflationary increases in the coming years.

Yesterday, the Obama administration announced that it wants to strengthen national investment Institutes (NIH) of the health research on Alzheimer's disease with $ 80 million in new funding in the budget proposal of the President for 2013 which will be published next week. Although it is not so surprising-there are always new initiatives in the budget of NIH proposed even during the budgetary rigor-administration is also taking the unusual step of setting aside $ 50 million for the Alzheimer's studies in the budget this year. The decision, which was made at a higher level than the NIH, set off a scramble for where to find the money and how to spend it, according to officials of the NIH.

The administration reacts to the increasing number of Alzheimer's disease, which now affects as many as 5.1 million Americans and could hit 10 million by 2050, according to a press release yesterday by the Ministry of Health and social Services of the United States. "We can not wait to act," the Department of Health and Human Services (HHS) Secretary Kathleen Sebelius said. The new money above $ 458 million that NIH already planned to spend on the brain disorder this year - also meets a new law that requires the government to come up with the plan of the disease a national Alzheimer effectively prevent and treat the disease by 2025

Congress decides to approve. or not $ 80 million for next year, the officials say the NIH has not yet been allocated to specific areas within the appropriations process. (the administration also requested $ 26 million for non-program -Research as caregiver support and public awareness.)

regarding the $ 50 million budget this year, half will go to genomics studies, the Director Francis Collins NIH said yesterday. According to Richard Hodes, director of the National Institute on aging (NIA), so-called genome-wide association studies (GWAS) have found several new genetic risk factors slightly increase the risk of Alzheimer ' Alzheimer. But researchers hope to find rare variants and explore why, for example, some people who wear APOE4 gene known risk never develop the disease. The plan is to study of Exome and whole genome using DNA from the same groups of Alzheimer's patients and healthy people who were part of GWAS studies. These cohorts give the initiative "a great start from the head and is why something like this could actually be done this year," says Hodes.

But exactly where the $ 25 million for genomics come from "is actively being discussed," said Larry Thompson, spokesman for the National Institute for Human Genome Research (NHGRI). NIH has not had much time to plan, he said: '. OK, let "The Ministry [HHS] and White House said:" We would make an initiative on this, "and we said," One possibility is to add the project to the list of $ 104 million year NHGRI genome sequencing program, which supports the three major sequencing centers, and more things to do.

The other $ 25 million will be "broadly" Alzheimer funding proposals to grant NIA and other institutes which have received well in the peer review, but just missed the cutoff funding says Hodes. Some of the funding can also be assigned as supplements to existing prices. This plan is similar to how the NIH spent a lot of $ 10 billion in financing Resumption Act 2 years that the agency received in 09 and had a few months to allocate. Hodes said a group of NIH institute directors advise Collins on which specific proposals to fund.

The set-aside for Alzheimer's disease will mean less money and less funded research proposals, in fields other than Alzheimer's disease, Hodes said. He said that while $ 50 million over the $ 31.0 billion budget NIH "is not great" (it was 0.16%), at a time of historically low success rate subsidy, "he there will undoubtedly be people who will be affected. "

"This is something that should happen only in the most exceptional circumstances, and in this case, the Administration has determined that emergency Alzheimer's disease and demography be such a circumstance" , Hodes said. One reassuring point: because $ 50 million is for one year only, it should not change the basic funding level institutes, he said.

Hoping to dispel confusion about the increasing confusion of genetic testing, the National Institutes of Health (NIH ) today unveiled a new database that lists thousands of tests voluntarily submitted by companies and non-profit laboratories.

Genetic tests now exist for some 2,500 diseases, cystic fibrosis APOE, which increases the risk of Alzheimer's disease. NIH established the Genetic Testing Registry for physicians, patients and researchers after experts suggested that such a database could improve transparency on genetic testing. Led by National Center for Biotechnology Information (NIH NCBI) database can be searched by condition test, gene, and the laboratory and includes information such as whether the test sequence the entire gene for mutations and look for errors specific. Links lead to resources like GeneReviews NCBI, which are brief descriptions of specific hereditary diseases and how to test for them.

Most genetic tests should not be approved by the Food and Drug Administration as long as they are performed as a laboratory service and not marketed as a medical device. NIH does not verify the information in the registry, but the applicant must certify that the data is accurate. "It is a great resource for those who are struggling to make sense of the complex world of genetic testing," said the director Francis Collins NIH in a press release timed with the celebration of the NIH Rare Disease Day .

The tests listed so many cover essentially Mendelian diseases and genes that affect the way people metabolize drugs. Exome are missing and whole genome sequencing tests, mutations found in the tumors, and direct consumer testing, such as analysis of the entire genome of 23andMe for disease risk markers. These could come later, said NIH.

In a unanimous opinion today, the Supreme Court of the United States rejected the patents behind a diagnostic test sold by Prometheus Laboratories San Diego, California. The decision was a blow to the biotech company and a win for a test laboratory linked to the Mayo Clinic in Rochester, Minnesota, who refused to pay royalties to Prometheus.

Mayo had developed its own diagnostic blood test, and Mayo officials argued that even if it was similar to the company, it did not violate the principles of patent law and has been medically higher. Mayo has attracted the support of amicus curiae briefs from a number of medical and leading scientific societies, while Prometheus had the support of the Biotechnology Industry Organization and other industry leaders.

The opinion of the Supreme Court, written by Justice Stephen Breyer cited the basic principles to reject Prometheus patents. According to the court, Prometheus sought to claim the processes that are not very far from natural phenomena; previous court decisions clearly show that natural phenomena are "not eligible patent." Breyer explained that the court does not allow monopolies on the "scientific basis of work tools and technology" because it "might tend to impede innovation more than it would tend to promote it. " The court also noted that Prometheus allegations fell short because his invention-a thiopurine drug monitoring process in the blood a-involved "course, a routine conventional activity previously carried out by researchers in the field. "

Battle on the Prometheus drug test was closely monitored because it can foreshadow decisions on other cases of high profile biotechnology, in particular the fight whether human genes can be patented . The court has been sitting on a request to review the validity of patents on BRCA1 and BRCA2 breast cancer genes and ovarian held by Myriad Genetics of Salt Lake City, Utah. A federal district court in 2010 found these assertions invalid because they were an attempt to kind patent. This decision went to a court of appeal, which partly accepted and partly rejected the Myriad patents. Both parties appealed to the Supreme Court, which has yet to say whether it will hear arguments on the Myriad case.

Patents of invention and blogger Dennis Crouch, in comments published today in the Patently-O column, anticipates that the Supreme Court will refer the Myriad case to the lower court for reconsideration. He also speculates that the lower court "could logically find" that, in light of today's decision, the isolated DNA quoted in Myriad BRCA gene patents is "patentable".

Kill harmful bacteria in hospitals is difficult; on the ground, it can be an even bigger problem. Now researchers may have a means for remote disinfection in a "flashlight" laptop that shines a cold plasma beam to kill bacteria in minutes.

Medical scientists have high hopes for plasmas. Produced in electric shocks, have already been demonstrated that these gas of free electrons and ions to destroy pathogens, help heal wounds, and selectively kill cancer cells. Nobody knows exactly how this works, but it seems that plasmas generate reactive oxygen species called in air. These highly reactive molecules which are present in our own immune system, and oxidize cell membranes damaged DNA.

plasma devices are already in clinical trials to see if they are safe to use. But these prototypes are limited: either they need an external power source to generate many kilovolts required electrical discharge, or they need an external gas supply and regulation to maintain the plasma. Such drawbacks, it is difficult to use the devices in the field of emergency calls, the response to natural disasters or military operations.

A group led by Xinpei Lu engineer at the Huazhong University of Science and Technology in China believes it has a device with none of the drawbacks. Powered by a normal 12-volt battery and operating in the open without a gas supply, the prototype, which they call a plasma torch should be portable enough to last. "It generates the plasma is even unplugged from the wall, even using very low power," said group member Kostya Ostrikov from CSIRO science and engineering materials in Lindfield, Australia.

The battery The lamp pocket is much too small to create a plasma itself, so that researchers use a common electronic device known as a booster to intensify the DC voltage to 10 kV. an output of the amplifier is connected to the shell unit or "earth" in the technical-speak while the other goes to a network of 12 thin, stainless steel needles which create an electric discharge pulsing rapidly. the circuit includes several resistors "ballast" that limit the discharge current so that the flashlight is safe to touch.

to test the device, the Lu group grew thick films of Enterococcus faecalis , bacteria which are known to infect root canals in the mouth and are highly resistant to heat and antibiotics. The researchers used some of biofilms supposedly that of the control samples and subjected others to the plasma torch for 5 minutes at a distance of 5 mm. Thereafter, they scored all samples with two fluorescent solutions: green indicates that the living cells, and red indicates that the dead cells.

The team found that the control samples remained green, while the treated samples had turned almost entirely red-even at the bottom of biofilms, which were about 17 deep cells. The results, which are published online today in the Journal of Physics D: Applied Physics , were still better than a nonportable plasma device that Lu had previously tested group.

Making truly portable device is a great advance, said Michael Keidar, a plasma physicist at George Washington University in Washington, DC "cold plasma operation in air is difficult, [and] it seems that they were able to operate, "he said. "This is a purely technical issue that has been resolved."

Miran Mozetic Engineer of the Jožef Stefan Institute in Ljubljana, Slovenia, highlights another advantage of the plasma torch: It uses only a meager 60 milliwatts per discharge. "This is an important fact because it indicates the battery [will] not to be exchanged or refilled frequently," he said.

Like any other medical device, the plasma torch will go through rigorous clinical tests. But Ostrikov said that in addition to smaller and optimizing its efficiency, the plasma flashlight is "almost" a device already shopping.

CORRECTION: This story has been given primary affiliation Kostya Ostrikov as the University of Sydney, while in fact CSIRO Materials Science and Engineering. The article has been corrected.

good news for people who hate large needles: Researchers have invented a device that could allow diagnostics to perform with a single drop of blood. The device is a container to a few millimeters wide, which consists of a conductive core covered with an elastic layer of polydimethylsiloxane or PDMS, a silicone compound. When the liquid is drained out of the PDMS layer wraps around the droplets that result due to its surface tension the same force as the water curl up on the sides of a glass. In this configuration, the droplet can not escape. To release, the researchers simply inserting a thin electrode: Together with the conductive base, the electrode creates an electric field which causes the layer of PDMS to unpack (as above shown). The researchers believe that their container, which is described in a paper published online today in the Proceedings of the Royal Society A could allow blood tests to be performed with a single drop of blood because it would be transported droplets evaporate or become contaminated. This would reduce patient discomfort, and perhaps save time. In addition, the researchers believe that their container can provide tiny amounts of drugs to diseased cells, which avoids having to administer potentially harmful drugs for the entire body.

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castor oil can have a bad reputation among the people who were force-fed spoonfuls like children, but it is not a myth that tonic has health effects. Today, scientists have elucidated the molecular mechanism of the active ingredient in castor oil, which has been used for thousands of years as a laxative and labor spillway. ricinoleic acid, which fatty acid is about 0% oil, binds to a particular receptor in the gut and uterus, the researchers found. The discovery explains how castor oil and could lead to development of drugs less unpleasant.

While taking a daily spoonful of castor oil diluted as general assistance for health is more fashionable, alternative health stores still sell the liquid foul-tasting as a laxative. The Food and Drug Administration has classified castor oil as "generally recognized as safe and effective," but researchers do not understand its mechanism.

"When you study classic, old drugs, is almost always learn something from them," said first author of the new study Stefan Offermanns, a biologist at the Max Planck Institute for Heart and Lung Research Germany. "The biggest surprise here was how specifically castor oil worked."

Offermanns and his colleagues were screening different fatty acids for their ability to bind to certain cell receptors when they have achieved success with ricinoleic acid. Knowing extensive use of castor oil in traditional and alternative medicine, the team decided to take a closer look at the compound. The use of a large library of molecules that block the cell receptors they studied, they were able to home in two as ricinoleic acid connects to: EP ₃ and EP ₄ . Both are prostaglandin receptors, which have different roles in the body, to change the structure of neurons to control how the blood clots. In experiments on mice, the researchers showed that ricinoleic acid induces its laxative effects and inducing labor by interacting with EP ₃ . When someone swallows castor oil, ricinoleic acid on locks EP ₃ molecules in the smooth muscle cells in the walls of the small intestine and causes contractions, which explains the efficiency of castor oil as a laxative. Similarly, researchers have shown that ricinoleic acid binds to EP ₃ and in the uterus causes contractions. The team published its results today in Proceedings of the National Academy of Sciences .

"There were many theories as to how castor oil worked, including broad toxicity to intestine cells and the effects on water and electrolytes," says Offermanns. But ricinoleic acid is much more accurate than those theories suggest, acting through a single receiver. How the receiver causes contractions, however, is still not known. But the new link between EP ₃ and bowel and muscle cells of the uterus could inspire the work to find out.

"They made these experiences quite elegant and complete," says biologist Phillip Bennett from Imperial College London. "And at one level, this finding is somehow a little quaint curiosity but there is more than that. "

the knowledge that ricinoleic acid binds to EP ₃ could be used to design drugs that target the receptor, said Bennett. These drugs could be used as laxatives or working without inducing side effects such as nausea, castor oil.

a daily dose of castor oil will not keep the doctor and modern medicine n ' has not yet backed claims that he also treats skin conditions, relieves pain and heals infections. So take castor oil with a grain of salt, or a spoonful of sugar.

The researchers understand why a popular therapy for the treatment of colon cancer often eventually stops working: The tumors naturally carry genetic changes that allow certain their cells to evade the drugs and continue to grow. The good news is that doctors may be able to detect these changes in patients' blood, then stop the cancer with another drug before it can grow again to a dangerous size.

Many people with advanced colon cancer are treated with proteins called antibodies that target a weakness of the tumor, a protein that stimulates the growth of cancer cells called EGFR. Antibodies often shrink tumors, but cancer usually comes back within 18 months. To investigate how this developed resistance, a team led by geneticist Alberto Bardelli from the Institute for cancer research and cancer treatment in Candiolo, Italy, increased colon cancer cells in boxes containing a growth medium laced with cetuximab anti-EGFR antibody called. The group now reports in Nature as the cells have become resistant to the drug because of changes in KRAS , a gene encoding a protein that may reactivate the growth path of EGFR when EGFR is itself blocked. The resistant antibody producing cells had mutations in KRAS and sometimes contain additional copies of the gene. The researchers also found these changes in biopsies of six patients with tumors that were resistant to cetuximab or a similar drug called panitumumab.

The blood of a cancer patient typically contains traces of DNA of the tumor. The Italian team and a separate group led by Luis Diaz oncologist at Johns Hopkins University in Baltimore, Maryland, have now found independently that KRAS mutations are detectable in blood samples from patients whose tumors have become resistant to drugs, Bardelli technology called a "liquid biopsy." the warning signs in KRAS appeared up to 10 months before the tumors become large enough to detect various standard imaging techniques such as X-rays. This suggests that clinicians could monitor patients' blood for resistance mutations and when they appear, give patients a second drug that also blocks the path of growth of EGFR, but in a way that KRAS mutation can not replace. the combination of such a drug called a MEK inhibitor with cetuximab killed colon cancer cells in a laboratory dish that were resistant to cetuximab alone group Bardelli reports.

"The concept of liquid biopsy, both groups used, is really a step forward, and I am sure it will be widely used in the clinic," said Bardelli, named online work today in Nature and the study of the Hopkins group.

another question was how resistance mutations got there. they were present in a few cells before the patient was treated with the drug, or did they occur after treatment? to find out, the team and his Hopkins colleagues at Harvard University have developed a mathematical model of the genetic evolution of the tumor that match their data KRAS mutations in the blood. They concluded that resistance mutations resulting from spontaneous changes in DNA that cells divide are present in some tumor cells even before the treatment. The model shows that the resistance is a "done deal", Diaz and his colleagues write. It is also probably inevitable for other so-called targeted therapies, such as those for melanoma and lung cancer, which also generally work for less than a year, Diaz said.

"The lessons here that resistance mutations occur spontaneously" into a tumor, even before therapy is tried, said Diaz. In rare cases, a patient-targeted therapy lived for years without develop resistance. But these tumors may be very young when the patient is first treated, or abnormally slow growth, Diaz said.

"these results are illuminating and sobering" because they show that resistance drug against the target colon cancer is inevitable, says oncologist Neal Meropol of Case Western Reserve University in Cleveland, Ohio. The treatments will target more than one molecular pathway, he said.

But Dominik Wodarz evolutionary biologist at the University of California, Irvine, also found the Hopkins study "encouraging" because the model seems to describe drug resistance in cancer and diseases such as HIV who are "very different from each other biologically." Although cancer is complex, given that its dynamics are "relatively simple" craft will help researchers better treatments, he said.

A man working for the World health Organization (WHO) on the campaign to eradicate polio was shot dead in Karachi, Pakistan, on the evening of 20 July. Muhammad Ishaq was shot outside his clinic in a slum in Karachi rough known as Gadap. Ishaq, who was the local community, died en route to hospital.

only 3 days earlier, two gunmen killed a Ghanaian doctor working for WHO and his Pakistani driver, participating in a national campaign of vaccination against polio in their car. The doctor was shot in the stomach; the pilot suffered a grazing wound on his shoulder. The two men are recovering.

After the first shot, the WHO has canceled the rest of the vaccination campaign in Gadap and implemented increased security measures instead.

Nobody has claimed responsibility for the shooting and there is no definitive evidence linking the two events, said Bruce Aylward, WHO Deputy Director General and longtime leader of global Initiative to eradicate polio. Similarly, it is unclear whether the shooting was random or polio workers targeted specifically. Until they get more evidence, said Aylward, "Our working hypothesis is that [the shootings] may be linked, and that affects our approach to security."

is Gadap slum densely populated with a large minority and migrant population. most residents of the tribal areas along the border with Afghanistan, where opposition to a government-run or a Western program is intense rumors abound that the vaccine against polio is dangerous and is part of a US campaign to sterilize Muslim children. About a month earlier, a leader of a faction of the Taliban in North Waziristan banned vaccination against polio in its part of the tribal area to stop the US drone strikes.

Expressing deep sadness, the WHO issued a statement saying that the shooting will not distract from the state progress of Pakistan made in its fight to eradicate polio. Pakistan and Afghanistan and Nigeria, is one of three so-called endemic countries where polio transmission has never been interrupted.