Swine flu pandemic over, says world health body

The swine flu pandemic has been declared officially over by the World Health Organization.

The body said it was moving to the "post-pandemic phase" after many countries, including the UK, had scaled down their emergency measures.

WHO director general Dr Margaret Chan said the virus had "largely run its course".

Millions of people were affected across the world by the infection after it emerged in April last year.

But the pandemic - the first for 40 years - proved much less deadly than many had feared.

In the UK, more than 450 people died, but that was well short of the 65,000 predicted as the worst-case scenario.

The decision by WHO reflects the fact that the virus is only circulating at relatively low levels, in most cases on par with seasonal flu activity.

In a telephone news conference, Dr Chan said: "The world is no longer in phase six of the pandemic alert. We are now moving into the post-pandemic period.

"The new H1N1 virus has largely run its course."

The WHO still said health officials should continue monitoring infection rates - as there is still a chance they could rise again - as well as updating their plans on the basis of what was learnt during the pandemic.

High stress 'delays pregnancy'

A scientific study has shown for the first time that high stress levels may delay pregnancy.

Oxford University experts measured stress hormones in women planning a baby naturally and found the most stressed had a reduced chance of becoming pregnant.

Relaxation might help some couples but more research is needed, they say.

The study, in the journal Fertility and Sterility, followed 274 healthy women aged 18-40 planning a pregnancy.

Age, smoking, obesity and alcohol are known to affect pregnancy success, but the influence of stress is less clear.
Markers for two stress hormones - adrenalin, the body's fight or flight hormone, and cortisol, connected with chronic stress - were measured in saliva.

Women with the highest levels of alpha-amylase (an indicator of adrenalin levels) had about a 12% reduced chance of getting pregnant during their fertile days that month compared with those with the lowest levels of the marker.

No difference in the chance of becoming pregnant was found with cortisol.

Anecdotal reports have long linked stress with infertility, but direct scientific evidence has been hard to find.

Dr Cecilia Pyper, of the National Perinatal Epidemiology Unit at the University of Oxford, said their study aimed to improve understanding of the factors that influence pregnancy in normal healthy women.She said: "'This is the first study to find that a biological measure of stress is associated with a woman's chances of becoming pregnant that month.

"The findings support the idea that couples should aim to stay as relaxed as they can about trying for a baby.

"In some people's cases, it might be relevant to look at relaxation techniques, counselling and even approaches like yoga and meditation."

The research was carried out in collaboration with the Eunice Kennedy Shriver National Institute for Child Health and Human Development in the US.

It is part of a larger study looking at the effect of factors like smoking, alcohol, and caffeine on chances of pregnancy.

Commenting on the study, Joanne Taylor, midwife for baby charity Tommy's said: "Stress does affect people in different ways, and therefore may affect some women's chances of trying to conceive.

"There are a number of ways in which women can prepare themselves for a healthy pregnancy - maintaining a healthy diet, taking folic acid supplements and keeping stress levels to a minimum is a good start."

Ovulation hormones make women 'choose clingy clothes'

Women are more likely to select clingy clothes when they are ovulating, a study has found.

But the University of Minnesota study of 100 women found these hormonal shopping habits were triggered by the proximity of attractive women.

The researchers suggest in selecting tighter clothes, the women were trying to stand out from love rivals.

The Journal of Consumer Research study said there should be more analysis of how hormones affected shopping habits.

Women at different stages of their menstrual cycle were shown images of attractive women living locally or far away.

They were then asked to choose clothes and accessories which they would like to buy.

Women who were ovulating and who had seen photos of attractive local women were most likely to buy "sexier" clothes compared with those shown photographs of unattractive local women or women who lived more than 1,000 miles (1,600km) away.

'Eye-catching'

Dr Kristina Durante, who led the research, said: "The desire for women at peak fertility to unconsciously choose products that enhance appearance is driven by a desire to outdo attractive rival women.

"If you look more desirable than your competition, you are more likely to stand out."

The team said even though the end result was about attracting the best romantic partner available, ovulating women's choice of dress was motivated by the other women in their environment.

"In order to entice a desirable mate, a woman needs to assess the attractiveness of other women in her local environment to determine how eye-catching she needs to be to snare a good man," she said.

And she said the study's findings could influence how and when products were marketed to women.

"Our findings suggest marketers for many types of female products are well served to strategically time their mailings, coupons, electronic solicitations, and direct requests to the specific window when women are ovulating."

Dr George Fieldman, a London-based psychotherapist, said the findings were interesting.

"What this study in part reveals is that people are only semi-conscious of the underlying reasons behind the choices they make in the context of buying sexy clothes," he said.

"Women do the choosing [of mates] but in order to enable them to choose, they need a good number of suitors to select from."

Girls now reaching puberty before 10 – a year sooner than 20 years ago

The latest generation of girls are reaching puberty before the age of 10, a new study suggests, raising fears they may also begin sexual activity earlier. Scientists have found that the average age that breast development begins is now nine years and 10 months – almost a year earlier than a previous study in 1991.

They have yet to discover the reason behind the phenomenon but believe it could be linked to unhealthy lifestyles or exposure to chemicals in food.

The study was carried out in Denmark in 2006, the latest year for which figures were available, but experts believe the trend applies to Britain.

Data from America also points to the earlier onset of puberty.

Scientists are worried that young girls are ill-equipped to cope with sexual development when they are still at primary school – and that exposure to hormones earlier could increase their risk from breast cancer.

“We were very surprised that there had been such a change in a period of just 15 years,” Anders Juul, head of the Department of Growth and Reproduction at the University hospital in Copenhagen, told the Sunday Times.

“If girls mature early, they run into teenage problems at an early age and they’re more prone to diseases later on.

"We should be worried about this regardless of what we think the underlying reasons might be.

"It’s a clear sign that something is affecting our children, whether it’s junk food, environmental chemicals or lack of physical activity.”

Hitting puberty early can mean longer exposure to oestrogen, which is a factor in breast cancer. There is also a greater risk of heart disease.

A number of artificially produced chemicals have been blamed for interfering with sexual development, notably bisphenol A, a plastic found in the lining of tin cans and babies’ feeding bottles.

Mr Juul’s research team is now testing blood and urine samples from girls in the study to see if a direct link can be drawn between early sexual maturation and bisphenol A.

Another factor in puberty could be diet. Children are eating more than previous generations and growing bigger — and in many cases becoming obese.

There has been a steady lowering in the onset of puberty. In the 19th century, it was at about 15 for girls and 17 for boys.

The international standard for normal puberty in white girls was set in the 1960s at 12 for the age when periods begin and at about 14 for boys when their voices break and their growth surges.

A more recent consensus in Britain has proved less conclusive.

“Although we don’t have clear data here, there is evidence the same thing [as in Denmark] is happening for reasons that we don’t understand,” said Richard Sharpe, head of the Medical Research Council’s human reproductive sciences unit in Edinburgh.

“We don’t know if this is the result of better nutrition or environmental factors, but it does create social problems for girls who are already living in a sexualised society.”

Gene link to meningitis infection

A set of genes which renders people more prone to meningitis has been pinpointed by researchers.

The international team compared DNA from 1,400 people with bacterial meningitis and 6,000 healthy individuals, Nature Genetics reports.

They found differences in a family of genes involved in the immune response seem to make people more or less susceptible to the infection.

It is hoped the findings will lead to the development of new vaccines.

The researchers were looking at meningitis caused by the Neisseria meningitidis bacterium, which leads to swelling of the lining of the brain and blood poisoning.

It is not the first time researchers have attempted to find out if some people are more likely to catch meningitis because of their genetic make-up.
But results have previously been unclear, probably because of the small number of people studied.

In the latest study, researchers first scanned the whole genetic code of 475 British patients with meningococcal disease and 4,700 healthy individuals.

They found a clear difference in a small set of genes known to be involved in the immune system response.

When they looked again in two other European populations they found the same result.

Vaccine

The genetic differences found means that, in some people, the bacteria is able to evade the immune system and cause infection, while other people' immune systems are better equipped to fight it off.

The genes encode for a protein called factor H, and factor H related proteins.

Where there are flaws, the meningococcal bacteria is able to bind to these proteins to prevent the immune system from recognising it - almost like a Trojan horse - enabling it to get a foothold.

Study author Professor Michael Levin, an expert in international child health at Imperial College London, said the findings would be particularly useful in developing a vaccine against meningitis B, which is now responsible for most cases in the UK.

There is already an effective vaccine against meningitis C.
"It seems that the genetic differences in factor H between people is what determines susceptibility or resistance.

"It suggests it may be an important protein to include in vaccines, and factor H is already one of the candidates for meningitis B vaccine."

He said the results will also help scientists better tailor vaccines to be effective in the whole population.

It may also open up avenues for improving treatment once people have bacterial meningitis, he said.

Sue Davie, chief executive of the Meningitis Trust, said: "This exciting work has thrown new light on factors that play a part in determining why some people get meningococcal disease and others do not.

"Further work will be needed to establish just what the genetic differences are in the genes which actually cause this susceptibility to invasive infection, but this is a promising start."

Large waist size linked to 'higher risk of death'

Men and women with large waists are at increased risk of dying young, a US study has found.

This is true regardless of their body mass index (BMI), research published in Archives of Internal Medicine suggests.

But very high waist measurements equivalent to UK size 24-26 in women and XXXXL in men appear to double the risk of mortality.

For the study researchers tracked more than 100,000 men and women aged 50 and older over nine years.

They also found that in women the link between a larger waist and a higher risk of death was strongest for those of normal weight.

More research is needed to find out why this is so, say the authors of the study.

Dr Eric Jacobs and his team at the American Cancer Society in Atlanta examined the link between waist circumference and risk of death among 48,500 men and 56,343 women.

Participants were predominantly white. At the start of the study, the average age of the men was 69 years and of the women, 67 years.

From 1997 until 2006 the deaths of any participants were tracked and the causes noted.

A total of 9,315 men and 5,332 women died during this time.

Whether participants were of normal weight, overweight or obese, researchers found that risk of death increased with increasing waist circumference.

This risk significantly increased in men with waists measuring 110cm or more and in women with waists measuring 95cm or more, the study found.

But it is only in men and women with very large waists (120cm or larger in men and 110cm in women) that the risk of death appears to double during the nine-year study.

The most common cause of death in those with the strongest link between mortality and waist size was respiratory disease, followed by cardiovascular disease and then cancer.

The study concludes: "Our results suggest that, regardless of weight, avoiding gains in waist circumference may reduce risk of premature mortality."

Dr David Haslam, chair of the National Obesity Forum, said the research is important.

"This underlines the message that fat inside the belly is dangerous.

"Even if you have a normal BMI and a big tummy then you are just as much at risk as someone who is classified as obese with a large tummy."

Previous studies have shown that abdominal obesity is a strong indicator for the development of coronary artery disease and is associated with insulin resistance and the development of Type 2 diabetes.

The risk is associated with the fat stores, which are not just under the skin but deep within the abdominal cavity.

WAIST SIZES - WOMEN*
Size 10 = 69 cm
Size 12 = 74 cm
Size 14 = 79 cm
Size 16 = 84 cm
Size 18 = 89 cm
Sizes 20-22 = 90-101cm
Sizes 24-26 = 102-113cm

WAIST SIZES - MEN*
Small - up to 78cm
Medium - 82.5-87.5cm
Large - 90-94cm
X Large - 96.5-101.5cm
XX Large - 104-109cm
XXX Large - 112-117cm
All sizes according to M&S*

Researchers Develop Wireless Glucose Monitor for Diabetics

Bioengineers in the United States have developed an implantable wireless monitor for diabetics that can measure glucose levels continuously for up to a year before needing replacement. The device, if approved by federal regulators, would give diabetics a more reliable and less painful alternative to current glucose monitoring devices.

The glucose monitoring system is designed to be implanted just under the skin, where it automatically measures glucose or blood sugar levels and transmits the data to an external receiver. The device, a small disc about 38 millimeters across and 16 millimeters thick, could be substituted for painful finger-stick devices and implanted needle-like sensors that monitor glucose levels continuously, but need to be replaced every three to seven days.

Diabetics have difficulty maintaining healthy blood glucose levels because they cannot produce enough of the sugar-processing hormone insulin - a condition called Type 1 or juvenile diabetes - or because the insulin they do produce is unable to properly convert dietary glucose into energy - a condition known as Type 2 or adult-onset diabetes.

Large studies have shown that strict blood sugar control, through continual glucose measurements and adjustment when blood sugar levels get too high or too low, reduces the risk of diabetic complications, including kidney, eye and heart disease.

Bioengineer David Gough of the University of California, San Diego is lead author of the study describing the new monitoring system and its successful performance in animal tests.

Gough says the sensor would allow diabetics to keep a much closer eye on their blood sugar levels than conventional methods. "So they could adjust the insulin or exercise, diet or other therapy and better manage their diabetes. So this device would be implanted subcutaneously for long periods of time, say a year or more," he said.

The monitor is made up of two oxygen sensors. One contains an enzyme catalyst called glucose oxydase that triggers a chemical reaction in proportion to the amount of oxygen consumed by sugar in the interstitial fluid beneath the skin.

The second sensor reads the amount of oxygen from the first sensor and compares it to a reference level, producing a blood glucose reading.

Gough says the dual sensors could be implanted during a simple outpatient procedure, at the waist or lower abdomen, or just below the collar bone, where heart pacemakers are often located.

The bioengineer says the readings would be sent wirelessly to a receiver outside the body. "You could have the receiver attached to your belt or it might ultimately be a cell phone or something like that," he said.

The wireless glucose monitor would guard against one of the most dangerous aspects of diabetes - hypoglycemia, a condition in which blood sugar levels fall very low. It is especially dangerous, Gough says, if the condition develops while a patient is asleep.

"Those people are under an immediate concern because they can lose cognitive ability and have an accident or something. So this device would warn when glucose was too low as well. And both of those things - both the short term problems of diabetes and long term problems of diabetes - could, in principal, be ameliorated," he said.

Gough says the glucose sensors could be used to send a cell phone wake-up call to parents of diabetic children if their child's glucose level dropped dangerously low during the night.

Researchers say their goal is to create a closed-loop system in which the wireless monitor continuously measures blood glucose and an external insulin pump automatically adjusts the amount of insulin being administered.

Gough says researchers hope to begin human clinical trials of the glucose monitor within the next few months and to gain federal regulatory approval soon after that.

An article describing the wireless blood sugar monitor is published in the journal Science Translational Medicine.

Rotavirus Vaccine Trials Successful; Researchers Call for Global Distribution

After successful clinical trials, researchers are calling for widespread distribution of a vaccine to prevent rotavirus - a severe gastrointestinal illness that kills more than a half a million children around the world each year.

Investigators are urging the use of the rotavirus vaccine in poor and developing countries after two clinical trials that showed it is safe and highly effective in protecting newborns against the deadly virus.

The vaccine, manufactured Merck, already is approved for use in the United States, but researchers wanted to see how well it works in less developed countries.

Dr. Roger Glass is Director of the John E. Fogarty International Center for Advanced Study in the Health Sciences at the National Institutes of Health near Washington.

In an interview from Swaziland, Glass said the vaccine has resulted in a significant decrease in the number of rotavirus cases in the United States.

"The vaccines that we are talking about have been licensed and used in the United States since 2006 and have already made a tremendous impact to reduce hospitalizations and clinic visits for diarrhea in just 3.5 years," said Dr. Glass.

But Dr. Glass noted that rotavirus kills 500,000 children a year in the 72 poorest countries.

Two international trials were carried out to test the vaccine's safety and effectiveness - one involving more than 2,000 healthy infants in Bangladesh and Vietnam. Some of the babies received the oral drug at 6, 10 and 14 weeks of age; another group of infants was given a placebo.

Researchers conducting a follow-up study nearly two years later found the rotavirus vaccine had reduced the number of severe gastrointestinal disease cases by nearly 50 percent.

A second study was conducted in Africa, where rotavirus claims almost a quarter of a million lives each year. Researchers conducting the trial in Ghana, Kenya and Mali, gave three doses of the vaccine to infants without symptoms. Investigators found there were 39 percent fewer cases of severe rotavirus with the vaccine.

Researchers found the vaccine had little or no side effects, according to Dr. Glass, who said widespread use of the rotavirus vaccine would save lives.

"We really hope that we with these results and with these findings that that mortality, those half a million deaths from rotavirus could be reduced by more than 50 percent through the use of this vaccine," he said. "This would further reduce diarrheal deaths in the world by about a quarter. And diarrhea, remember, is the second most common cause of death in children under five."

Three years ago, the World Health Organization recommended routine use of the rotavirus vaccine in countries where it has been found to be safe and effective. Dr. Glass says he hopes the results of these two studies lead to the use of the vaccine in other countries where it is needed most.

The two studies on the effectiveness of the rotavirus vaccine in Asia and Africa are published in the journal The Lancet.