Royal Holloway University of London

The ‘man flu’ is real – viruses want to kill men more than women.

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Throughout history, men have been ridiculed for their apparent inability to handle simple viruses like the common cold – otherwise referred to as the “man flu” in these cases.

But as it turns out, there may be some truth to the man flu label as researchers find that certain viruses may present themselves more virulently in men than in women.

And it may have to do with evolution.

Researchers believe viruses favour women as hosts because they are more likely to pass on the virus to their babies.

“It has already been established that men and women react to illness differently, but evidence shows that viruses themselves have evolved to affect the sexes differently,” Vincent Jansen, professor at the School of Biological Sciences at Royal Holloway University of London, and co-author of the study, said in a statement.

Researchers looked at HTLV-1, a virus known to cause leukemia in infected people.

Infected women tend to develop leukemia less often than men, who are more likely to die from the disease.

By using mathematical modelling, researchers set out to show that natural selection favours viruses that have a lower rate of death in women than in men, especially if the virus can be passed from person to person and from mother to child.

Researchers used population samples from Japan and the Caribbean.

They found that Japanese men infected with the HTLV-1 virus were two to 3.5 times more likely to develop leukemia than women. However, the likelihood of the virus progressing to leukemia was about equal in men and women in the Caribbean.

Scientists believe the virus has become less fatal in women because the HTLV-1 virus can be passed through breastfeeding, a practice that is more prolonged in Japan.

Researchers concluded that women were proven to be more valuable hosts for pathogens because they are able to pass them on in more ways than men can.

“Pathogens are adapting to be less virulent in women to increase their chances of being passed on to the next generation during pregnancy, birth and infancy,” says Dr. Francisco Ubeda of Royal Holloway. “Survival of the fittest is relevant to all organisms, not just animals and humans. It’s entirely probable that this sex-specific virulent behaviour is happening to many other pathogens causing diseases.”

A previous study by Standford University School of Medicine in 2013 found that men and women also have different reactions to flu vaccinations.

Standford researchers found women had a stronger antibody response than men, which gave women better protection against the flu.

This, they say, was more apparent in men with higher testosterone levels which scientists believe weakens a man’s immune system.

Bee-friendly plants put to the test

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Honeybee on lavender (c) Science Photo Library

Researchers have used an experimental garden to put pollinator-friendly plants to the test.

The University of Sussex scientists counted the number of insects visiting the plants in their garden.

They say their findings show that insect-friendly plants are just as pretty, cheap and easy to grow as less pollinator-friendly varieties.

Their results are published in the Journal of Functional Ecology.

PhD student Mihail Garbuzov used 32 different varieties of popular garden plants. These included some nectar-rich and highly scented plants he thought would be attractive to insects and some that seemed to be less attractive.

While the small-scale study did not produce an exhaustive list of the best plants for pollinating insects, the team says the data has put a number on just how many more pollinators the right plants can attract.

Mr Garbuzov told the BBC: “Some of the best plants attracted approximately 100 times as many insects as the worst.

“And the plants that are attractive to insects are not more expensive, and they’re just as pretty.”

The researchers wrote in their paper that there was “great scope for making gardens and parks more insect friendly” by selecting the right plants.

Tips for insect-friendly gardening are already available from a variety of sources, but the researchers say they are largely based on “opinion and general experience”.

The aim of this study, said Prof Francis Ratnieks, from the University of Sussex, was to “put that advice on a firmer scientific footing, by gathering information about the actual number of insects visiting the flowers to collect nectar or pollen”.

Counting bees

Honeybee on a flower (c) Ethel M Villalobos
  • Bees have different colour-detection systems from humans, and can see the world in ultraviolet. This helps them to detect the flowers they pollinate and take nectar from.
  • Pollination is essential for agriculture, as well as the reproduction of non-food flowers and plants. According to the UN Food and Agriculture Organization, pollinators including bees, birds and bats are involved in more than a third of the world’s crop production.
  • Honeybees evolved to make honey as a food source for the colony. Selective breeding of European honeybees by humans has produced colonies that make excess honey for us to harvest.

The researchers gathered their data simply by visiting each of the patches of flowers every day over two summers and counting the number of insects on the flowers.

Their results did lead them to make some horticultural recommendations – they found that borage, lavender, marjoram and open-flower dahlias varieties were very good for insects.

The colourfully named bowles mauve everlasting wallflower was also very attractive to pollinators, while the least attractive flowering plant for insects was the very popular geranium.

Marjoram, the researchers say, was probably the best “all-rounder”, attracting honey bees, bumble bees, other bees, hover flies, and butterflies.

Borage was the best for honey bees and lavender and open-flowered dahlias were most attractive to bumblebees.

The team put a number of varieties of lavender to the test and found that highly bred hybrids, including some with novel colours – such as white or pink – that have been carefully bred into the plants proved the most attractive to insects.

Dr Nigel Raine, from Royal Holloway University of London, commented that with bee populations declining across the world, “we can all give bees a helping hand by planting the right flowers to give them the nectar and pollen they need”.

“This study highlights that it’s important for bee-friendly gardeners to choose what you plant with care,” he added.

“Gardeners and town planners should think carefully about the mixture of flowers they plant to ensure food is available for a wide range of bees and other important insect pollinators.

“It’s also important to cater for the needs of the rarer species and provide food at times when there might be fewer wild flowers in bloom.”

In another prior study, a team from the University of California San Diego used this ‘taste test’ to work out if bees are able to detect the scent of a flower. If the bee detects a floral scent, it will stick out its tongue.

‘Fat’ drug could treat epilepsy.

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A substance made by the body when it uses fat as fuel could provide a new way of treating epilepsy, experts hope.

Researchers in London who have been carrying out preliminary tests of the fatty acid treatment, report their findings in Neuropharmacology journal.

They came up with the idea because of a special diet used by some children with severe, drug resistant epilepsy to help manage their condition.

The ketogenic diet is high in fat and low in carbohydrate.

The high fat, low carbohydrate diet is thought to mimic aspects of starvation by forcing the body to burn fats rather than carbohydrates.

 “Start Quote

The identification of these fatty acids is an exciting breakthrough”

Simon WigglesworthEpilepsy Action

Although often effective, the diet has attracted criticism, as side-effects can be significant and potentially lead to constipation, hypoglycaemia, retarded growth and bone fractures.

By pinpointing fatty acids in the ketogenic diet that are effective in controlling epilepsy, researchers hope they can develop a pill for children and adults that could provide similar epilepsy control without the side-effects.

In early trials, the scientists, from Royal Holloway and University College London, say they have identified fatty acids that look like good candidates for the job.

They found that not only did some of the fatty acids outperform a regular epilepsy medication called valproate in controlling seizures in animals, they also had fewer side-effects.

But many more tests are needed to determine if the treatment would be safe and effective in humans.

Prof Matthew Walker, from the Institute of Neurology, University College London, said: “Epilepsy affects over 50 million people worldwide and approximately a third of these people have epilepsy that is not adequately controlled by our present treatments.

“This discovery offers a whole new approach to the treatment of drug-resistant epilepsies in children and adults.”

Simon Wigglesworth, deputy chief executive at Epilepsy Action, said: “We know the ketogenic diet can be a highly effective treatment for children with difficult to control epilepsy and it is starting to be used for adults.

“The diet is high in fats and low in carbohydrates and the balance of the diet needs to be carefully worked out for each child. Although some children manage the diet very well, others find the diet unpleasant and difficult to follow. Children can also experience side-effects including constipation and weight loss.

“The identification of these fatty acids is an exciting breakthrough. The research means that children and adults with epilepsy could potentially benefit from the science behind the ketogenic diet without dramatically altering their eating habits or experiencing unpleasant side-effects.

“We look forward to seeing how this research progresses.”

Source:BBC