UK researchers say they can find no proof that a particular virus is the cause of chronic fatigue syndrome (CFS) or ME, contrary to recent claims.

The Imperial College London team say they want to share the findings as some patients are pinning their hopes on drugs to fight the virus called XMRV.

They analysed blood samples from 186 patients with CFS and found none had the virus, PLoS One journal reports.

Experts said the latest findings would be a bitter disappointment to many. They said more trials were under way and when these report in coming months, scientists will be able to draw more firm conclusions.

Work in the US, published in Science, had found the retrovirus in 68 of 101 CFS patients. The UK team say the conflict between the two studies might be down to differences between the patients enrolled or the way the research was conducted.

Or there might be different geographical types or strains of XMRV.

Regardless, they say potent antiretroviral drugs should not be used to treat CFS because there is not enough evidence that this is necessary or helpful.

The drugs may do more harm than good, they say.

Professor Myra McClure, one of the Imperial College London investigators, said: “We are confident that our results show there is no link between XMRV and chronic fatigue syndrome, at least in the UK.”

She said they had used extremely sensitive DNA testing methods, called polymerase chain reaction, to look for the virus.

“If it had been there, we would have found it.”

‘Disappointing’

Co-author Professor Simon Wessely said the findings did not invalidate all previous research, some of which has shown that CFS can be triggered by other infectious agents, such as Epstein Barr Virus.

The charity Action for ME said it was disappointing to hear about these findings, but said no single small-scale study could be conclusive.

Dr Charles Shepherd, of The ME Association, said it was important to remain open-minded.

“We need to be extremely cautious until we know more. There has been enormous interest in this from patients.

“Some have been led into believing the cause and a test has been discovered and that treatment is just round the corner and that is not the case.

“Over the next few weeks and months we will have more results and then we can come to a conclusion.

“If it turns out that XMRV is important, we will have to start looking at whether it is worthwhile testing for it and treating it.”

In a statement, the charity Invest in ME said the original Science study was of the “highest quality”, and that much more work was required before any firm conclusions could be drawn.

Officials also said they were investigating several troubling outbreaks of drug-resistant H1N1 but noted they were limited so far and that there were no indications yet the virus was mutating in a sustained way.

The World Health Organization said H1N1 flu was moving eastward across Europe and Asia after appearing to peak in parts of Western Europe and the United States.

At least 6,770 deaths have been recorded worldwide since the swine flu virus emerged in April — but officials always stress the confirmed count represents only a fraction of the actual cases, as most patients never get tested.

There are “early signs of a peak in disease activity in some areas of the northern hemisphere,” the WHO said in a statement.

Transmission keeps intensifying in Canada, with the highest number of doctor visits by children. But U.S. officials saw signs of a slowdown.

“We are beginning to see some declines in flu activity around the country but there is still a lot of influenza,” the Centers for Disease Control and Prevention’s Dr. Anne Schuchat told a news conference.

“It is still much greater than we would normally see this time of year.”

Recent decline in cases
A team at flu test maker Quest Diagnostics analyzed 142,000 U.S. flu tests and found a similar pattern, with tests showing a decline in flu-like illness since October 27.

WHO said Norway and countries farther east including Georgia, Lithuania, Moldova and Serbia were reporting sharp increases in influenza-like illness or acute respiratory infection.

Kazakhstan, Uzbekistan and parts of Afghanistan — particularly the capital, Kabul — are reporting higher numbers of flu cases. Israel is also reporting sharp increases.

“Essentially what is happening is that it is spreading eastward,” Anthony Mounts of WHO’s influenza team told Reuters. “Typically, seasonal influenza always starts west and moves eastward. It seems to be following that pattern except it is coming very early this year.”

Influenza can hit several peaks in a single season. Experts said weeks or months more of disease could be expected and noted that during the 1957 pandemic, a busy autumn was followed by a lull and then infections surged again starting in January.

Vaccination campaigns are beginning in many countries but companies reported some trouble making vaccine from the H1N1 virus. The United States was still struggling to distribute vaccines but Canadian Health Minister Leona Aglukkaq said enough vaccine for almost half of Canada’s population would have been shipped out by the end of the next week.

Mutant viruses
British health officials said they were investigating the likely person-to-person spread of a drug-resistant strain of swine flu.

The Health Protection Agency reported five confirmed cases in Wales of patients infected with H1N1 resistant Roche AG and Gilead Sciences Inc’s antiviral drug Tamiflu.

Another antiviral, GlaxoSmithKline and Biota Inc’s Relenza, were effective in the patients, the HPA said.

The patients had serious conditions that suppressed their immune systems, which can give the virus a better than usual opportunity to develop resistance, the HPA added.

U.S. CDC officials also said they were investigating four cases of H1N1 resistant to Tamiflu at Duke University hospital in North Carolina. “All four patients were very ill with underlying severely compromised immune systems and multiple other complex medical conditions,” Duke said in a statement.

Health experts are looking for any sign that H1N1 is mutating into a drug-resistant form. Last year, the seasonal version of H1N1, a distant cousin of the pandemic strain, developed resistance to Tamiflu.

In Norway, officials were investigating a mutated strain in some patients that they said could be responsible for causing severe symptoms.

“The mutation could be affecting the virus’ ability to go deeper into the respiratory system, thus causing more serious illness,” the Norwegian Institute of Public Health said in a statement.

WHO said the mutation did not appear to be widespread in Norway and the virus remained sensitive to antivirals and pandemic vaccines.

A similar mutation had been detected in H1N1 viruses in several other countries, including China and the United States, in severe as well as in some mild cases, it said.

But the Opinion Research Corporation survey, released Tuesday morning, indicates a small majority continue to say that the government and private industry eventually will produce enough of the vaccine for the virus, also known as swine flu, to inoculate everyone who wants it.

According to the poll, 51 percent of those questioned are confident in the government’s ability to prevent an H1N1 epidemic, with 49 percent not confident. The number of Americans who are confident is down 8 percentage points from August, while the number of those not confident is up 9 percentage points.

“Only one in 10 say they are ‘very confident’ that the government can ward off an epidemic,” says CNN Polling Director Keating Holland. “But the growing doubts may not be directly related to the shortfall of vaccine so far.”

Fifty-three percent of those questioned say that government and private industry can produce enough vaccine for everyone who wants a swine flue shot. That number is essentially unchanged since August.

The poll indicates that one group in particular is skeptical about the government’s efforts to battle swine flu.

“Only 43 percent of mothers with children under the age of 18 are confident in the government’s ability to prevent an epidemic,” says Holland. “That’s 7 points lower than fathers and 10 points lower than people who don’t have young children. Mothers are also most likely to think that there will not be enough vaccine to go around.”

According to the poll, 57 percent approve of how President Obama’s handling the government’s response to H1N1, with 4 in 10 saying they disapprove.

The CNN/Opinion Research Corporation poll was conducted October 30 through November 1, with 1,018 adult Americans questioned by telephone. The survey’s sampling error is plus or minus 3 percentage points for the overall sample.

Federal health officials report that the swine flu remains widespread in 48 states but add that the supply of vaccine has reached 32 million doses, double what was available two weeks ago.

Sources: cnn.com

The virus, xenotropic murine leukemia virus-related-virus or XMRV, was found in approximately 67 percent of 101 patients that suffered from chronic fatigue syndrome by Vincent C. Lombardi, Ph.D. from the Whittemore Peterson Institute in Reno, Nevada, and his team.

The team also found the virus in nearly 4 percent of healthy comparison subjects, which suggests that millions of Americans could carry this mysterious virus that was first detected in prostate cancer.

Robert H. Silverman, Ph.D., from the Cleveland Clinic’s Lerner Research Institute, said, “The discovery of XMRV in two major diseases, prostate cancer and now chronic fatigue syndrome, is very exciting. If cause and effect is established there would be a new opportunity for prevention and treatment of these diseases.” Silverman is part of the team of scientists that first discovered XMRV, and was among the researchers that linked the virus to prostate cancer and chronic fatigue syndrome. However, it is still not proven that XMRV actually causes either prostate cancer or chronic fatigue syndrome.

In patients that have prostate cancer, the virus is seen in the patients that carry a genetic mutation that disables a key virus-fighting immune response. This virus is also seen in patients with chronic fatigue syndrome with and without this mutation.

Where did this virus come from, you may ask? This virus is very closely related to a retrovirus that has become a part of the mouse genome. Oddly enough, XMRV cannot infect mouse cells, but it can easily infect human cells. It is unlikely that so many people have caught XMRV from mice. It is more likely that the virus is spread from person to person, but how that happens is still unknown.

An editorial that was written by John M. Coffin from Tufts University, Boston, and Jonathan P. Stoye from the Institute for Medical Research, London, accompanies the Lombardi report, which is in the current issue of the online journal Sciencexpress.

Stoye and Coffin note that if 4 percent of healthy people truly carry XMRV, it means that this virus is astonishingly widespread. They say, “If these figures are born out in larger studies, it would mean that perhaps 10 million people in the United States and hundreds of millions worldwide are infected with a virus whose pathogenic potential for humans is still unknown.”

What is known is that the viruses that are closely related to XMRV do cause many different diseases, which include cancer, in other warm-blooded animals. Further study could reveal that XMRV is a cause of more than one well-known “old disease.” This could lead to potentially important implications for prevention, diagnosis and therapy.

Chikungunya virus has spread beyond Africa since 2005, causing outbreaks and scores of fatalities in India and the French island of Reunion. It also has been detected in Italy, where it has begun to spread locally, as well as France.

“We’re very worried,” Dr. James Diaz of the Louisiana University Health Sciences Center told a meeting on airlines, airports and disease transmission sponsored by the independent U.S. National Research Council.

“Unlike West Nile virus, where nine out of 10 people are going to be totally asymptomatic, or may have a mild headache or a stiff neck, if you get Chikungunya you’re going to be sick,” he said.

“The disease can be fatal. It’s a serious disease,” Diaz added. “There is no vaccine.”

Chikungunya infection causes fever, headache, fatigue, nausea, vomiting, muscle pain, rash and joint pain. Symptoms can last a few weeks, though some suffers have reported incapacitating joint pain or arthritis lasting months.

The disease was first discovered in Tanzania in 1952. Its name means “that which bends up” in the Makonde language spoken in northern Mozambique and southeastern Tanzania.

The virus could spread globally now because it can be carried by the Asian tiger mosquito, which is found in Asia, Africa, Europe, the Americas, Australia and New Zealand.

In the United States, the mosquito species tends to live in southern regions east of the Mississippi but has been found as far afield as western Texas, Minnesota and New Jersey.

Health officials are greatly concerned about the appearance of Chikungunya in the islands of the Indian Ocean — Mauritius, Seychelles and Reunion — which have beach resorts frequented by European tourists.

“It is hyper-endemic in the islands of the Indian Ocean,” Diaz told the meeting.

“Travel by air will import the infected mosquitoes and humans,” he added. “Chikungunya is coming.”

Diaz warned of possible double-infections involving Chikungunya and dengue fever or malaria, which are also carried by the Asian tiger mosquito.

The spread of the disease could be greatest in so-called mega-cities such as Mumbai and Mexico City, which have large and impoverished populations, poor health controls and water systems that provide ready breeding grounds for mosquitoes, Diaz said.

West Nile, spread by a different mosquito species, first appeared in New York in 1999 and now can be found in most of North America.

Sources:  reuters.com

Scientists have produced compelling evidence that a virus known to cause cancer in animals is linked to prostate cancer in humans.

The researchers from the University of Utah and Columbia University medical schools found the virus in 27% of the 200 cancerous prostates they looked at.

They say it was associated with more aggressive tumours and found in only 6% of non-cancerous prostates.

The finding raises the prospect of one day producing a vaccine.

Previous research has linked XMRV (Xenotropic murine leukaemia virus) to prostate cancer but not specifically to the aggressive form of the disease.

Retrovirus

XMRV is a retrovirus like HIV which works by inserting a copy of its own DNA into the chromosomes of a cell they infect.

We still don’t know that this virus causes cancer in people, but that is an important question we are going to investigate. Dr Ila Singh, University of Utah

Where this occurs next to a gene that regulates cell growth it can disrupt the normal development of the cell.

XMRV is known to cause leukaemia and other tumours in animals.

Dr Ila Singh, who led the study from the pathology department at the University of Utah, said: “We still don’t know that this virus causes cancer in people, but that is an important question we are going to investigate.

“One of the things peculiar about this virus is that it has an androgen response element – it grows better in the presence of testosterone and possibly other steroid hormones.

PROSTATE CANCER FACTS Most common cancer in men in UK 10,000 die each year Most cases are in those aged 70-74 Higher rates in most deprived populations Source: Cancer Research UK

“This is particularly interesting because if we can prove that it responds to oestrogen it could have a role in other cancers.

“We are already looking at the bodies of 100 women and 100 men, who died from other causes, to see if any other organs carry the virus.”

Risk factor

Dr Helen Rippon, Head of Research Management at The Prostate Cancer Charity, said the research was intriguing but posed several key questions about the role the infection plays in prostate cancer.

It is critically important to identify key triggers of prostate cancer to improve early detection Dr Helen Rippon, Prostate Cancer Charity

She said: “Around the world, extensive work is being undertaken to identify risk factors for prostate cancer which will enable treatments and tests for the disease to be refined.

“It is critically important to identify key triggers of prostate cancer to improve early detection of the disease in men with potentially life threatening prostate cancer.”

Dr Chris Parker, Cancer Research UK’s prostate cancer expert at the Institute of Cancer Research said: “This exciting study raises the possibility that the virus might contribute to the development of some prostate cancers.

“In the future, if it turns out to be true, then we could speculate about the possibility of vaccination to protect against prostate cancer, similar to the approach now used to prevent cervical cancer.”

Sources: http://news.bbc.co.uk