Category Archives: Human Longevity

Archaeological work at the Border Cave site has revealed the earliest evidence for cooked root vegetables. Border Cave lies between South Africa and eSwatini and has a remarkable record of human habitation.

Hot, roasted root vegetables are comfort food, and a plateful of carbohydrate is both satisfying and nutritious. Archaeologists have found that our ancestors thought so, too. A team working at the site has discovered and documented the remains of starchy underground plant stems (called rhizomes) cooked 170,000 years ago.

Border Caves roasted rhizomes were identified as Hypoxis angustifolia (yellow stars). This was done by comparing their shape and internal anatomy to those of modern rhizomes which today grow in countries along the eastern flank of Africa. The distribution extends much further too, for example into Yemen.

If, as seems likely, Hypoxis had a similar distribution in the past, it would have provided a secure staple food for people travelling within and out of Africa.

Our findings suggest that the food was transported to the cave and then cooked. The food could easily have been consumed directly in the field by the collectors, but our findings suggest this wasnt the case, adding extra information about social behaviour and sharing and a glimpse into ancient communal behaviour 170,000 years ago. Food was the focus for satisfying physical and social hunger.

Hypoxis angustifolia plants are gregarious so many can be harvested at once. Wooden digging sticks or sharpened bones may have been used to dig rhizomes from the ground.

The food was carried home to the cave, perhaps as a hide-wrapped parcel or a simple bunch tied with leaves.

Wood was also collected for the cooking fire that probably burned to small coals and hot ash before the rhizomes were added directly to the ashes for roasting. Some South Africans are familiar with this cooking technique: as children we made askoek (ash cakes) directly on coals and tapped them on rocks to dislodge the ash before garnishing our culinary treasures with apricot jam.

Some of the thumb-sized Border Cave rhizomes were lost in the ashes where they were burned and thus preserved for archaeologists. We know that they were burned while still fresh and green because the charred rhizomes have split surfaces. This was caused by shrinkage when moisture was rapidly expelled. Many starchy root vegetables can be eaten raw, but their nutritional content is much greater when cooked (the human gut can then access the glucose better and absorb much more of it).

Cooking made Hypoxis rhizomes easy to peel, and rendered them digestible by releasing glucose and breaking down the fibre. Such treatment was particularly important for the aged members of the group and small children that might otherwise have had difficulty chewing the rhizomes.

The Border Cave occupants were modern humans (Homo sapiens) with the same nutritional needs as people today. To enable our large brains to function we need to consume about 100g of carbohydrate per day. Hypoxis rhizomes may have fulfilled that need in the past.

We know, too, that Border Cave dwellers also ate meat because we have recovered the cooked bones of wild animals that were eaten in the cave. In Africa, game meat is lean, especially in the dry season when animals lose weight. Lean meat protein cannot be metabolised by humans in the absence of either carbohydrates or fat.

The addition of some carbohydrate to their diet would then have enabled early humans to process protein effectively. A balanced, healthy diet with a combination of cooked carbohydrate and protein the real palaeo-diet - increased human fitness and longevity.

We discovered the first of the rhizomes in 2016 while digging in Border Caves ashy sediments. The sediments date between 170,000 and 100,000 years ago.

In total, 55 whole charred rhizomes were recovered, all from the same species. We worked together in the field over a period of four years, collecting modern plants with rhizomes so that we could compare these with the Border Cave ones in order to identify them.

With a permit from local wildlife authorities, we surveyed the Lebombo Mountain hillside near the cave for interesting plants with appropriate rhizomes. When a plant could not immediately be identified it was planted in a vegetable garden to await flowering. When each plant was securely identified, its rhizome was charred, examined microscopically, and compared with Border Cave specimens.

Eventually patience was rewarded, and a combination of morphological and anatomical evidence showed that the Border Cave rhizome was a Hypoxis.

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How we deduced that our ancestors liked roast vegetables too - The Conversation Africa

Rafael Nadal said passion and positivity had helped him reach an unprecedented third decade ranked world number one, after defying the ravages of injury and the critics who said his all-action game was too tough on his body.

Despite a steady stream of foot, knee, back, arm, hand and wrist injury setbacks, the 33-year-old has returned time and again to become the only player to top the rankings in three different decades.

"I can't say I have been lucky with injuries, because I have not," the Spaniard said on Saturday, when asked about his longevity in the game.

"But there is no secret, no? There is only about passion, about love for the game, and about being able to stay positive in the tough moments."

Nadal's physical, uncompromising approach is often contrasted with his great rival Roger Federer, who appears more effortless on court and -- after far fewer injuries -- is still going strong at 38.

But the fighting qualities that have taken Nadal to 19 Grand Slam titles on court have often been evident off it, as he was repeatedly able to recover from injury and return to the top.

"It's true that I went through some tough situations during all my career. But I was able to always, with probably the positive attitude and with the right people around -- they were the key -- I was able to find a way to keep going, no?" he said.

"It's difficult for me to imagine because for my style of game, as a lot of people said, my career should be little bit shorter. But here we are. Happy for that.

"Even for me is a big surprise to be where I am at my age."

Spain's Rafael Nadal said even he was surprised at his longevity in the game

Originally posted here:
'Passion, love' - Nadal's tips after defying injury to reach third decade on top - Yahoo News Australia

It's no secret that today's most successful companies are built on relationships. Customers crave real connection with brands for more meaningful engagement and experiences, and employees need it for a sense of belonging that directly affects the quality of service they deliver. Organizations, meanwhile, need it for staying relevant, driving loyalty, and increasing spending. We may live in a hyper-digital world, but prioritizing humanity offers major competitive advantages. This is especially true for hotels, where the emotional connection--providing that "home away from home" feeling--is critical.

The focus of the hospitality industry for the foreseeable future will be about fostering deep relationships and emotional connections. Here are my top recommendations for hotels to successfully do so:

Engage data wherever possible. Use modern technology to gain knowledge about guests and provide experiences that nurture genuine relationships. This knowledge can be derived by analyzing data related to how they spend with your brand, most recent interactions or even predictive data based on things like past transactions and engagements. Combining big data with cognitive computing (artificial intelligence and/or machine learning technology) helps glean key insights that allow your brand to better serve guests, putting you one step ahead of the rest. This data-driven experience- combined with partnerships with certain vendors- allows guests to order car service, schedule a class or massage, or order food at a moment's notice from their preferred vendors (you could even feature daily menu specials in guests' rooms to reflect their dietary restrictions or affiliations). It's these kinds of actions that make guests feel heard and truly cared for. Leveraging data in the right way (remember to be transparent in how it's collected and used) always keeps customers coming back.

Promote custom messages and offers. Nearly 75% of guests appreciate custom messages and offers. This could be a list of nearby activities based on a customer's TripAdvisor ratings or a personalized message via customers' channel of choice to inform them of things like confirmed reservations, early check-in options or changes to an itinerary. For business travelers, consider personalized reminders about upcoming meetings or conference show happenings (of course, data is integral to achieving these more personalized objectives). Guests should also be able to instantly initiate conversations with experts should they have any questions. These are all critical to relationship building for driving loyalty and repeat spending.

Don't forget your employees. When talking about relationship building, it's critical that employees be considered (after all, the employee experience is the new customer experience). Building authentic and genuine relationships with employees is as critical as the customer experience itself. Research shows that when employees have solid relationships with their employers, they are happier and higher performing. Economists at the University of Warwick, for example, found that a general feeling of happiness among employees led to a 12% spike in productivity while unhappy workers proved 10% less productive. More productivity equals more profitability, period. A great example of this is the Ritz-Carlton's 21-day employee engagement strategy. I encourage you to check it out.

We live in an age where authenticity, transparency and "realness" is valued above almost everything else: the products or services a company offers, achievements and accolades, and even prices. We are certain to see the continued value and importance of relationship building as hotels prioritize human connection. Customers and employees are setting higher standards for their work and experiences, and organizations that meet those standards are sure to see higher revenue.

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The Importance of Relationship Building for Hotel Revenue and Longevity | By Robert Reitknecht - Hospitality Net

January 9, 2020 Researchers may have discovered a way to turn back the clock on aging heart muscles in fruit flies, a development that could lead to new therapies for older humans with heart disease.

Hua Bai, Ph.D., an assistant professor of genetics, development and cell biology at Iowa State University, led a study, published recently in the academic journal Autophagy, that explores the genetic mechanism that causes fly cardiac muscles to deteriorate with age. Bai said the research team restored much of the cardiac function in middle-aged flies, which experience many of the same heart maladies as middle-aged humans.

The researchers approach starts with autophagy, a cellular cleanup process that removes and recycles damaged proteins and organelles. The autophagy process slows with age, which can lead to the weakening of cardiac muscles. Bais research team looked at a key genetic pathway conserved in virtually all organisms on Earth related to autophagy that balances organism growth with nutrient intake. This pathway, called mechanistic target of rapamycin (or mTOR), has long been linked to tissue aging, Bai said. One of two complexes that underlie the mTOR pathway, referred to as mTORC2, decreases with age as autophagy declines. But the researchers found that transgenically boosting mTORC2 strengthens heart muscles of older fruit flies.

Boosting the complex almost fully restored heart function, Bai said.

The discovery that enhancing mTORC2 slows the decline of the critical autophagy process could have big implications for how doctors treat patients with heart disease, one of the leading causes of the death in the United States. While flies and humans might seem to be worlds apart evolutionarily, Bai said the two species hearts age in a similar fashion. By middle age, cardiac muscles in both species tend to contract with less strength and regularity.

The fly model can be useful for developing drug target discoveries that could have a big impact on human health, Bai said.

The researchers arrived at their conclusions after conducting thousands of video recordings on cardiac muscles in fruit flies of various ages. High-resolution, high-speed cameras measured the activity of the flies cardiac muscles. The experiments showed that boosting mTORC2 could restore a five-to-six-week-old flys heart function to that of a fly between one and two weeks old. Thats like restoring a middle-aged heart to how it functioned during young adulthood, Bai said.

Because flies live only between two and three months, its much easier for scientists to study aging and longevity in flies than in more long-lived species, he said. And the ability to manipulate the fly genome also makes them ideal for genetic study and a common model organism, he said.

See the original study

Reference:

1. Kai Chang, Ping Kang, Ying Liu, et al. TGFB-INHB/activin signaling regulates age-dependent autophagy and cardiac health through inhibition of MTORC2. Autophagy. Published online: 29 Dec 2019. https://doi.org/10.1080/15548627.2019.1704117.

Read more:
Fruit Fly Hearts Show How to Keep Human Cardiac Muscle Young - Diagnostic and Interventional Cardiology

Good news for stressed-out students: there may be a link between stress in early life and longer lifespans, according to researchers at the University of Michigan.

The research is being conducted at the Jakob Lab, a molecular, cellular and developmental biology laboratory, and focuses on oxidative stress, a natural byproduct of metabolism, and its potential ability to increase lifespan. The lab uses genetically identical worms to study aging.

Postdoctoral fellow Daphne Bazopoulou, a key contributor to the ongoing project, explained what oxidative stress is and why the group chose to study it in worms.

These are oxidants that every organism produces, and these are byproducts of metabolism, and these have been linked to oxidative damage which contributes to aging, Bazopoulou said. Worms produce those oxidants at very high levels during development and they do that naturally so this was a little bit weird because we knew from studies before that excessive oxidants might do harm, however, these juvenile worms were able to recover by themselves.

Ursula Jakob, the labs primary investigator, said the researchers observed that oxidative stress in juvenile worms resulted in longer lifespans, leading them to begin their experiments.

The worms that have the highest levels of reactive oxygen species during this early stage were the ones that were most stress-resistant and the longest lived of the whole population, Jakob said. That was something that was very intriguing because it suggested that you can have these events very early in life in an organism that triggers this production of reactive oxygen species, and that will then extend the lifespan of that sub-population of worms.

Bazopoulou said they induced specific amounts of oxidative stress in these worm populations during early-life stages to test if it increased lifespan.

The main message is that oxidants in early life might predispose the organisms to withstanding stress, Bazopoulou said. They were becoming preconditioned; they were experiencing some early-life stress which made them battle stress that they were encountering later in life.

Bazopoulou said the lab planned to investigate this specific mechanism throughout an organisms lifespan and how it may affect predisposition to age-associated diseases.

We are also interested now in seeing whether those early-life oxidants can predispose organisms to better battle age-related pathologies such as neurodegenerative disorders like dementia and Alzheimers, Bazopoulou said.

LSA freshman Liam Thew Forrester, an undergraduate research assistant in a different lab at the molecular and behavioral neuroscience institution, studies stress-induced mood disorders. He shared his excitement at the findings of this stress-related research.

I was really surprised by it, its really interesting to think that the stress can actually be beneficial if its early on because that could vastly change how we do things, not just for longevity, it could help with the stress-induced disorders as well, Forrester said.

Jakob said she hopes to eventually develop interventions to help people combat the health and lifestyle struggles of aging.

This suggests that at a very early stage in life you can positively affect lifespan by, in this case, changing the levels of reactive oxygen species, Jakob said. If we can find out what are the mechanisms that are set in motion at a juvenile stage but ultimately are responsible later in life for higher stress resistance and longer life, maybe we can find an intervention that targets directly those processes so that we actually still have a chance to benefit from this information.

Jakob explained the goal of this research is to have a real impact on human health and physiology. Her lab plans to continue investigating the unknown factors that affect aging.

If we understand all the long-term effects that have been set into motion in early development, maybe we can mimic those long-term effects by pharmacological interventions or other interventions, Jakob said. What are ultimately the changes in these organisms when it comes to aging and death that allows them to live longer?

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Research: Early-life stress potentially linked to increased longevity - The Michigan Daily

A team of researchers from Germany and Greece recently identified several new properties of the human brain that could explain how our unique intelligence and consciousness emerges.

Science doesnt know why humans are more intelligent than spiders, monkeys, or birds. It has nothing but unsubstantiated theories to offer us when we wonder why a sunset can bring us to tears but a butterfly doesnt know Miles Davis from the sound of thunder. Whatever is happening inside our heads isnt the same as what occurs in other creatures.

The busiest, most complex part of the human brain is the cerebral cortex. Within its layers, scientists have found a thicker tissue area than other animals have. Our usual test subject, rodents, have brains that mimic the human brain in many ways, but this isnt one of them. The researchers took a look at how brain activity manifests in the second and third cortical layers, and what they discovered appears to be confirmation that our individual neurons can perform functions once thought impossible.

While the exact nature of brain activity is a mystery, we do have a fairly decent understanding of how it functions. The human brain is a neural network that sends and receives information from point to point where different neurons work on different parts of a problem. When we perceive something, for example, our brain has to decide if its near or far, big or small, red or green, and so forth. It does this by abstracting information from various input points and outputting a response. You can think of it like a computer that uses transistor gates to perform calculations.

Animals and insects can perform these kinds of calculations too. We know birds have an advanced understanding of aeronautics and many mammals can navigate across thousands of miles with pinpoint precision. But the way humans do it both consciously and subconsciously is believed to be unique.

In their recent study, the team from Germany and Greece took a deeper look at the branching connections between our brains neurons. What they discovered was that individual neurons in the human brain can perform calculations that wed previously assumed were the result of numerous neurons networked together.

Per the teams research paper:

It has long been assumed that the summation of excitatory synaptic inputs at the dendrite and the output at the axon can only instantiate logical operations such as AND and OR. Traditionally, the XOR operation has been thought to require a network solution. We found that the dCaAPs [the newly identified functions of human brain neurons] activation function allowed them to effectively compute the XOR operation in the dendrite by suppressing the amplitude of the dCaAP when the input is above the optimal strength.

Basically, the researchers figured out that the human brain can modulate the amplitude of electrical activity in order increase the longevity and efficacy of its signals. This, apparently, allows individual neurons to do more than just figure out if something is one thing or another, it allows them to perform an XOR calculation, something previously thought impossible for a single neuron in the human brain.

Its unclear exactly what this new information means, but its possible that the extra computational power provided by this seemingly unique trick of the human brain could explain our ability to manifest our brain activity as what we perceive as human intelligence or our own consciousness.

Well need a lot more research in order to clarify what the newly-identified electrical activity does and whether or not it is actually responsible for higher brain function, or even unique to humans. But this is an exciting thread that could, potentially,answer the ultimatequestion of how human intelligence and consciousness emerges.

Want to help? Consider donating your brain to a medical research facility after youre dead so that work like this can continue.

Read next: Remembering Stephen Hawking on his 78th birthday: A legacy of humanity

Read more here:
Scientists may have found the missing link between brain matter and consciousness - The Next Web

Understaffing and high employee turnover are significant concerns in the hospitality industry today. According to a recent report, Trends in Hospitality Training & Development 2019, by CHART and TDn2K, more than 69 percent of responding organizations report being understaffed in front-of-house hourly positions (with 94 percent annual turnover), and 93 percent are understaffed in back-of-house hourly positions (with 105 percent annual turnover). With estimated turnover costs of just over $1,800 per hourly employee, employers are asking the question, How do we retain the people we already have?

While there are multiple reasons that employees may leave, many of which are out of the control of employers, one element that can be addressed by nearly every organization has been shown to offer a significant benefit: focused training for managers. The CHART/TDn2K study found that increasing manager training in two key areas, leadership development and human-resources topics, resulted in a marked decrease in turnover rates for hourly employees.

According to the study, organizations that spent more than 10 percent of total manager training time on leadership development and/or HR topics saw reduced turnover rates ranging from 25-35 percent.

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Leadership development training gives managers the skills they need to more effectively communicate, motivate teams and manage people. Good leaders inspire and encourage their team members, so it follows that employees whose direct managers have training in this area experience greater success and job satisfaction, which often translates to longevity. Additionally, investing in the development of emerging leaders aids retention by showing employees that growth opportunities exist within the organization.

Human resources topics such as discrimination and harassment also have come to the forefront as hot-button issues faced by many organizations in recent years. Understanding of and sensitivity to these topics can go a long way toward improving workplace culture. In addition to helping employees feel safe and respected at work, training managers to proactively address these kinds of HR issues tells employees that the organization cares, which can positively influence their desire to stay.

By implementing focused training for managers, organizations create better, more prepared leaders who can effect positive changes in organizational culture, including increased job satisfaction and employee engagement. This in turn can significantly lower turnover, resulting in reduced expenditures associated with recruiting, onboarding and training new hires.

Monique Donahue is the director of e-learning for Hilton Grand Vacations in Orlando. She is president elect of the Council of Hotel and Restaurant Trainers (CHART). She can be reached at: [emailprotected]

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Looking to reduce turnover? Start with manager training - Hotel Management

Do you know how the genes of the long-lived differ from those of ordinary people?Do you know how to supplement longevity factors effectively?The year 2020 has just begun, and the global life science community has already caused a sensation. Auckland Genetics Research Center, the worlds top life science research institution, has published its research results, and announced the official unveiling of the secret to long life.

New Zealands latest finding

Centenarians have longevity codes in their bodies

Through the research of 100 people over the age of 100 in New Zealand, we found that they lived longer mainly because they were genetically different from us.Dr. Van Blith Merion from Auckland Genetics Research Center said that they found that APOE and FOXO3A, two genetic factors that contribute the most to longevity, were found in the genes of centenarians, and have successfully developed orally-consumed supplements that can stimulate the growth and synthesis of these two life factors, making it possible for ordinary people to achieve the effect of longevity.

The reporter learned that this is by no means alarmist, but has a rigorous scientific argument and has obtained the consensus of the entire life science community. It is reported that this two longevity factors have different division of labor, APOE can make the bodys lipid metabolism healthier, and FOXO3A, on the other hand, can block cell division cycle, repair DNA damage, promote cell autophagy, enhance the antioxidant capacity of cells, and prevent cell canceration. In addition to carry this kind of gene like centenarians, ordinary people can also synthesize these two gene factor components in the bodies through an enzyme called NAD+.

Everyone is born with NAD+, which is also the reason why our young people are generally in good health. However, for every ten years of age, the content of NAD+ in the body decreases by half, and by the age of 40, many human bodies are unable to produce NAD+ on their own, leading to cellular senescence,Dr. Van Blith Merion said.

Ezz brand NMN come on the market

Compound NMN products allow ordinary people to enter the age of longevity

Because of the larger molecular weight, how to increase the content of NAD+ in the body by supplementing the precursor substance NMN of NAD+ has become the research focus of Auckland University of Technology. For this, Auckland Genetics Research Center, invested heavily in expert resources and huge funds. And after a hard struggle, the research center eventually made a breakthrough, and developed the worlds most advanced compound NMN supplements - EZZ brand NMN.

According to clinical trial data, EZZ brand NMN solves the problem of poor absorption of traditional NMN products, and greatly improves the retention of NAD+ active ingredients in the body after two hours after taking orally by adopting the compound formula, so as to increase the contents of the two longevity factors APOE and FOXO3A in the body, reduce blood lipid, repair damaged cells, prevent cell cancer, and play the effect of gene anti-aging. According to clinical blind test, compared with traditional NMN products, the efficacy of this compound product can be increased by more than 10 times.

Industry insiderssaid that with the launch of the new EZZ NMN supplements by Auckland Genetics Research Center, a new era of low-cost, high-purity NMN has arrived. Since then, every person can use the money for a cup of coffee per day to help the body achieve the purpose of delaying aging, let the body function keep refreshat all times, and eliminate all kinds of diseases of the elderly. It is reported that effective NMN products are expected to extend the life of ordinary people by 30 percent or more.

Media ContactCompany Name: EZZ Pty LtdContact Person: AndyEmail: Send EmailCountry: GermanyWebsite: ozezz.com.au

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A New Zealand life science expert has unlocked the longevity code Ezz brand NMN has realized gene anti-aging - Press Release - Digital Journal

Living a longer and healthier life most relates to ones diet. Experts recommend eating at least five portions of fruit and vegetables every day, basing meals on higher starchy foods like potatoes, bread and rice, having some dairy or dairy alternatives, eating some protein, choosing unsaturated oils and spreads, and drinking plenty of fluids. Getting enough of the recommended amount of physical exercise and avoiding smoking and drinking can lead to a longer life. However, there is also a delicious treat one can add into their diet, and if eaten in moderation, it may also help to increase life expectancy.

How dark chocolate could help you to live longer

Losing weight

In his book, Eat Chocolate, Lose Weight, Will Clower explained how Bettina piece of dark chocolate 20 minutes before and five minutes after a meal can help cut a persons appetite by an impressive 50 percent.

According to Mr Clower, this is because chocolate triggers the hormones that tell the brain its full.

DONT MISS

Brain power

Dark chocolate helps to improve blood flow to the brain and researchers have found that it could even help with Alzheimers.

In a trial published by Nature Neuroscience, it was discovered that the high flavanol found in dark chocolate helped to enhance debate gyrus (DG) function.

DG is the region of the brain in which declines are associated with human ageing.

Read the original here:
How to live longer: Eating this delicious treat could increase your life expectancy - Express

In the last few months, schools all over the country have closed because of outbreaks of norovirus. Also known as stomach flu, norovirus infections cause watery diarrhea, low-grade fever and, most alarming of all, projectile vomiting, which is an extremely effective way of spreading the virus.

Norovirus is very infectious and spreads rapidly through a confined population, such as at a school or on a cruise ship. Although most sufferers recover in 24 to 48 hours, norovirus is a leading cause of childhood illness and, in developing countries, results in about 50,000 child deaths each year.

Interestingly, not everyone is equally vulnerable to the virus, and whether you get sick or not may depend on your blood type.

I am a microbiologist, and I got interested in norovirus because, while norovirus symptoms are distressing under any circumstances, my encounter with the virus was particularly inconvenient. During a seven-day rafting trip down the Grand Canyon, the illness passed through the rafters and crew, one by one. Obviously, the wilderness sanitary facilities were not the best to cope with this outbreak. Luckily, everyone, including me, recovered quickly. It turns out that norovirus outbreaks on Colorado River rafting trips are common.

As debilitating as the illness it causes can be, the norovirus particle is visually beautiful. It is a type of virus known as non-enveloped or naked, which means that it never acquires the membrane coating typical of other viruses, such as the flu virus. The norovirus surface is a protein coat, called the capsid. The capsid protects the norovirus genetic material.

The naked capsid coat is one factor that makes norovirus so difficult to control. Viruses with membrane coatings are susceptible to alcohol and detergents, but not so norovirus. Norovirus can survive temperatures from freezing to 145 degrees Fahrenheit (about the maximum water temperature in a home dishwasher), soap and mild solutions of bleach. Norovirus can persist on human hands for hours and on solid surfaces and food for days and is also resistant to alcohol-based hand sanitizers.

To make things worse, only a tiny dose of the virus as few as 10 viral particles is needed to cause disease. Given that an infected person can excrete many billions of viral particles, its very difficult to prevent the virus from spreading.

When norovirus is ingested, it initially infects the cells that line the small intestine. Researchers dont know exactly how this infection then causes the symptoms of the disease. But a fascinating aspect of norovirus is that, after exposure, blood type determines, in a large part, whether a person gets sick.

Your blood type A, B, AB or O is dictated by genes that determine which kinds of molecules, called oligosaccharides, are found on the surface of your red blood cells. Oligosaccharides are made from different types of sugars linked together in complex ways.

The same oligosaccharides on red blood cells also appear on the surface of cells that line the small intestine. Norovirus and a few other viruses use these oligosaccharides to grab onto and infect the intestinal cells. Its the specific structure of these oligosaccharides that determines whether a given strain of virus can attach and invade.

The presence of one oligosaccharide, called the H1-antigen, is required for attachment by many norovirus strains.

People who do not make H1-antigen in their intestinal cells make up 20% of the European-derived population and are resistant to many strains of norovirus.

More sugars can be attached to the H1-antigen to give the A, B or AB blood types. People who cant make the A and B modifications have the O blood type.

Norovirus evolves rapidly. There are 29 different strains currently known to infect humans, and each strain has different variants. Each one has different abilities to bind to the variously shaped sugar molecules on the intestinal cell surface. These sugars are determined by blood type.

If a group of people is exposed to a strain of norovirus, who gets sick will depend on each persons blood type. But, if the same group of people is exposed to a different strain of norovirus, different people may be resistant or susceptible. In general, those who do not make the H1-antigen and people with B blood type will tend to be resistant, whereas people with A, AB, or O blood types will tend get sick, but the pattern will depend on the specific strain of norovirus.

This difference in susceptibility has an interesting consequence. When an outbreak occurs, for example, on a cruise ship, roughly a third of the people may escape infection. Because they do not know the underlying reason for their resistance, I think spared people engage in magical thinking for example, I didnt get sick because I drank a lot of grape juice. Of course, these mythical evasive techniques will not work if the next outbreak is a strain to which the individual is susceptible.

A norovirus infection provokes a robust immune response that eliminates the virus in a few days. However, the response appears to be short-lived. Most studies have found that immunity guarding against reinfection with the same norovirus strain lasts less than six months. Also, infection with one strain of norovirus offers little protection against infection from another. Thus, you can have repeated bouts with norovirus.

The diversity of norovirus strains and the impermanence of the immune response complicates development of an effective vaccine. Currently, clinical trials are testing the effects of vaccines made from the capsid proteins of the two most prevalent norovirus strains.

In general, these experimental vaccines produce good immune responses; the longevity of the immune response is now under study. The next phase of clinical trials will test if the vaccines actually prevent or reduce the symptoms of norovirus infection.

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More here:
Your blood type may influence your vulnerability to norovirus, the winter vomiting virus - The Conversation US