This GIF Only Takes 6 Seconds To Show How Herd Immunity Works!!

When enough people are vaccinated against a contagious disease they will create protection for those who aren’t vaccinated, in an effect known as “herd immunity”.

This effect can eventually lead to the eradication of diseases and also helps those who are not able to receive vaccinations due to medical reasons, such as immunosuppressed children or those going through chemotherapy. But does it mean it’s a good idea to ride on the back of the vaccinations of others? Here’s why it’s important to keep vaccination rates as high as possible.

Redditor theotheredmund has created a GIF that shows how a contagious disease passes through different populations with varying percentages of its people vaccinated. The simulated data was based on research from a study published in Epidemiologic Reviews in 1993.

The 6-second animation clearly shows how populations with fewer people vaccinated allow the disease to spread significantly quicker and further through the chain of humans. On the other hand, if there is any outbreak in a population with widespread vaccination, the disease struggles to spread and the chains to others are cut. However, the effect of herd immunity is significantly dampened at each level of declining vaccination rates.

Essentially, the decision to not vaccinate affects the whole community, not just the individual.

“Once you read a high enough level of vaccination, the disease gets effectively roadblocked. It can’t spread fast enough because it encounters too many vaccinated individuals, and so the majority of the population (even the unvaccinated people) are protected,” the creator explains on Imgur.

Note: This article was originally published by  TOM HALE.


Do Vitamin D Supplements Really Prevent Cold And Flu Infections?

Vitamin D, something that your immune system uses to produce antimicrobial deterrents, may be the key to fighting off colds and influenza viruses. According to a review published in the British Medical Journal, if it formed a more major part of the diet of those in the UK, up to 3 million people could avoid falling ill every single year.

This is being widely reported as a proverbial miracle of modern medical research, but there have been plenty of warnings before about taking unnecessary dietary supplements and the harm they can cause you. So what’s the deal this time?

Recent analyses have placed Vitamin D supplements as being anywhere from “promising” to “inconclusive” – essentially, there’s no strong evidence that taking them, if you’re a perfectly healthy individual, will make any difference to your biological workings.

Most people, particularly those in Northern Europe, do not get enough sunlight in the winter months, which is required by the body to generate Vitamin D. Low levels of this particular chemical compound correlates with a weaker immune system, so it’s been thought for some time that those lacking it would be more likely to be successfully infected by pesky viruses in the winter months.

Multiple trials on using supplements to prevent such infections have been conducted many times before, but the results have never been clear-cut, and medical professionals are wary about overselling the efficacy of potential treatments to patients in need.

This new review, led by the Queen Mary University of London (QMUL), looked at 11,321 people across 25 separate trials in order to see if there was any definitive correlations present in this regard. These studies looked at an impressive range of infections, from common cold strains to full-blown influenza.

They came to the conclusion that, for every 33 people regularly taking Vitamin D supplements as part of a balanced diet, one of them would not experience a cold or flu infection during the year. This would make it more effective than the flu vaccination.

Overall, extended to the entire UK, this works out to be 3 million people without the sniffles. This would not just be great for their own health, but would be a huge boost to the British economy in terms of work hours not lost to sickness.

However, before leaping to the nearest pharmacy to ask for vitamin supplements, it’s worth looking at theaccompanying editorial in the journal. It points out that within just three months, two studies – this one, and another earlier one – have come to very different conclusions, with one concluding that vitamin D has no effect on disease prevention, with the exception of muscoskeletal diseases.

“Given the short time between articles, why are the conclusions so different?” the editorial reads, adding that the authors of it think that “there are reasons for viewing the headline result cautiously.”

“In absolute terms, the primary result is a reduction from 42% to 40% in the proportion of participants experiencing at least one acute respiratory tract infection,” it notes. This means that taking Vitamin D supplements reduces your risk of getting a cold by 2 percent, which is very minor indeed.

The editorial also points out that the term “acute respiratory tract infection” is loosely defined throughout the 25 trials, meaning that it’s not really clear what Vitamin D supplements are actually having an effect on.

Should these results change clinical practice? Probably not,” it concludes. Right now, the supplement hypothesis is just that – a hypothesis – and one that needs plenty more randomized and controlled trials to be confirmed.

So, for now, Vitamin D supplements remain in the “inconclusive” column. Don’t believe the hype just yet.

Note: This article was originally published by Robin Andrews.

The Deepwater Horizon Disaster Released A Heart-Damaging Pollutant

The Deepwater Horizon (DH) oil spill in 2010 was by far the largest of its kind in US waters. An inextinguishable fire killed 11 workers on the rig, and 4.9 million barrels’ worth of oil escaped into the Gulf of Mexico. BP was fined $18.7 billion for malpractice – the largest corporate settlement in American history.

The catastrophe caused untold havoc to regional wildlife, including – as a new study in Scientific Reports found – corrupting the hearts of fish. This is sad enough on its own, but it turns out that the same type of pollution might be affecting humans too.

A team from the University of Manchester painstakingly analyzed the effects of crude oil on the cardiovascular systems of species endemic to the Gulf of Mexico, and found that a specific compound was responsible for disrupting and damaging heart functioning.

“These open ocean fish are hard to study in captivity, but understanding what component of the Deepwater Horizon disaster oil negatively affected the heart is really important,” study co-author Dr Holly Shiels, a senior lecturer in animal physiology at the University of Manchester, said in a statement. “It could help us distinguish the cardiotoxic potential of environmental catastrophes.”

Although this identification is important in marine biology terms, it turns out that this particular hydrocarbon – phenanthrene – also negatively affects all vertebrates the same way, including humans. This means that if we ate enough phenanthrene-containing fish, for example, our tickers’ rhythm or resilience could be in trouble.


As the authors of the study also point out, DH-afflicted fish are not the only source of this heart-harming hydrocarbon available to us. Phenanthrene is often a common component of plenty of petrol varieties used in most forms of ground-based transportation, including cars, motorbikes, buses, and so on.

Worryingly, air pollution is at an all-time high. Tens of millions of people are dying from respiratory or cardiovascular illness linked to this unfortunate phenomenon every single year. Those living near busy roads are much more likely to have dementia in later life.

Identifying phenanthrene as a “major worldwide cause of vertebrate cardiac dysfunction” – as the authors note in their paper – is a welcome step in identifying the most dangerous aspects of pollution. Still, unless anything is done to stem the tide of oil spills and stamp out the horrifying scale of contemporary air pollution, this won’t mean anything at all.

If anything, this study underlines the fact that we are not segregated from the environment. What’s bad for it is bad for us, and that’s all there is to it. There’s no escaping that fact.

Note: This article was originally published by Robin Andrews.

This New Treatment Could Make Pancreatic Cancer A Manageable Disease

Cancer is among the leading causes of death worldwide. There were approximately 14m new cases diagnosed and 8.2m cancer related deaths in 2012. This figure is expected to rise by about 70% over the next two decades.

Pancreatic cancer is the eighth most common cause of cancer-related mortality worldwide, with incidence almost equalling mortality – that is, almost as many die from the disease each year as develop it. There are several types of pancreatic cancer, but more than 90% of cases are pancreatic ductal adenocarcinomas (PDAC). PDAC has one of the lowest five-year survival rates as well as a general resistance to chemotherapeutic approaches. As a result, the treatment of PDAC remains a major challenge in oncology.

There is a common theme in some of the most prolific aggressive cancers, and that is a protein known as S100P. This protein is highly expressed in pancreatic cancer and once this protein is activated it results in signalling changes that tell the cell to grow and divide remarkably quickly. This induces the cells to spread and create new cancerous growths around the body. This makes S100P a great target for developing new drugs to prevent the spread of aggressive cancers – and pancreatic cancer in particular.

Seeking a fix

Scientists at the University of Hertfordshire, in collaboration with Dr Tatjana Crnogorac-Jurcevic of Barts Cancer Institute, Queen Mary University of London, used computational chemistry methods to design new compounds that would in theory prevent S100P from being activated.


In a project funded by the charity Worldwide Cancer Research, Dr Stewart Kirton of the University of Hertfordshire designed the structures of new drugs based on Cromolyn, a drug that can be used to prevent allergy-induced asthma. These new compounds were then synthesised by Hertfordshire’s Dr Sharon Rossiter and her team of chemists.

I started my PhD with the aim to identify the lead compounds that could be further developed as a suitable drug that would present the further spreading of the cancer. My supervisory team included scientists with a wide variety of disciplines: Dr Louise Mackenzie (pharmacologist), Dr Sharon Rossiter (chemist), Dr David Chau (cell biologist) and Dr Pryank Patel (biochemist), whose expertise had helped to focus my research.

I then used molecular biology techniques to screen a bank of 93 synthetic compounds for their ability to prevent the activation of S100P. From that work, 18 potential drugs were identified and then tested to see how toxic they are to cells.

The compounds themselves did not kill the cancer cells, but they did prevent them from migrating. This is an excellent profile for a drug to treat this type of cancer, since in theory any drug that worked in this way would both slow down the progression of the cancer and make it more vulnerable to chemotherapy.

The next stages are to look at ways to make sure that there are as few side effects possible by making small changes to the structure of the most promising candidate drugs. If successful, it might make a difference for patients between no survival – and a prolonged life. One day, pancreatic cancer may even become a manageable disease.

Note: This article was originally published on The Conversation by Deborah Ogbeni, PhD candidate, University of Hertfordshire and Louise Mackenzie, Senior Lecturer Pharmacology, University of Hertfordshire.

Brain Scans May Be Able To Help Diagnose Babies At Risk Of Developing Autism

The signs that a child has autism spectrum disorder, or ASD, normally start to appear when they are around two years of age. But if doctors could diagnose ASD at a much earlier age, then steps could be taken before it has fully manifested that may allow both child and family manage the condition better.

Researchers now think that they could identify those most at risk of developing autism within the first year of a child’s life. The study, published this week in Nature, looked at the brain scans of 106 babies who came from families that already had a child with autism. From these scans taken at both six and 12 months of age, they then identified markers in the brains that predicted whether or not the child will develop ASD.

“Our study shows that early brain development biomarkers could be very useful in identifying babies at the highest risk for autism before behavioral symptoms emerge,” explains Joseph Piven in a statement. “Typically, the earliest an autism diagnosis can be made is between ages two and three. But for babies with older autistic siblings, our imaging approach may help predict during the first year of life which babies are most likely to receive an autism diagnosis at 24 months.”

If scientists are able to diagnose autism in children before it manifests itself, it may also allow for researchers to begin other studies looking into potential ways to prevent it from forming in the first place. The causes behind the condition are still unknown (despite what you may here from incredibly dubious films currently on release), with explanations ranging from underlying genetics to different ways in which the brain develops, although it is likely to be a mixture of factors involved.

Autism is generally seen as a condition that is more common in boys than in girls, but this is now being challenged. Part of the reason behind the skew may simply be down to the fact that this imbalance between the sexes is expected, and so when girls display behaviors indicative of autism they are often missed. It could also be that girls are simply better at masking them. But this is now being acknowledged, and better understood, and some even predict that in the UK alone there may be as many as 100,000 undiagnosed girls with autism, who are not getting the support they desperately need.

The results are still very early stage, and the researchers do not recommend rolling the technique out into clinics any time soon, but it could now form a basis for further research to investigate these early cues that may help speed up diagnoses. It could at least give parents an indication that they should be looking out for the signs of ASD as the child grows.

Note: This article was originally published by Josh Davis.

Copying Rabies Could Provide A New Way To Treat Brain Cancer

It is a deadly disease that has so far evaded a complete cure. Successful treatment of rabies depends on how quickly medical help is given after exposure to the virus, and if it manages to reach the nervous system then it is almost invariably fatal. But the deadly virus may hold the key to solving one of the trickiest problems in medicine.

The human body has evolved such an efficient protection system, that for a long time doctors have been trying to figure out a way to breach the blood-brain barrier in order to deliver drugs to the brain. It seems that turning to nature itself may well help solve the problem. By studying how the rabies virus manages to infect brain tissue, researchers may have found a way to deliver tumor-killing drugs.

During its long history of evolution, the rabies virus has found a way to effectively bypass the blood-brain barrier, rather than breach it. When someone is infected with rabies, it is most often delivered to the muscle tissue through the bite of an infected animal, like a dog or a bat. The virus then travels through the tissue until it hits upon the central nervous system, using this to travel up and into the brain. Researchers are now mimicking this process in order to find a novel way to get drugs to brain cancers.

In a new study, published in Advanced Materials, researchers engineered gold nanoparticles into the shape of the rabies virus and coated them in some of the surface proteins found on the virus, before injecting them into mice that were bred to have brain tumors. They found that within hours the particles had migrated through the nervous system of the mice and into the brain. By then heating these particles with lasers that pass harmlessly through the skin, the researchers claimed that they were able to significantly shrink the brain tumors due to the heat emitted from the gold.

Whether or not this research could lead to an effective treatment for brain tumors is, however, still to be seen. Some researchers question whether or not the gold nano-particles only home in on the tumor cells, or if they are also found in other tissues of the body, meaning that any treatment with lasers could in fact have inadvertent side effects and kill other healthy body cells. If these questions cannot be addressed, it will make it significantly more difficult to get approval for use in humans.

Note: This article was originally published by Josh Davis.

The Appendix Might Not Be So Useless After All

The appendix has long been a bit of a mystery. At its worse, it’s considered a useless evolutionary throwback whose sole purpose is to give you a nasty case of appendicitis. However, one research team of medical doctors have a theory of what purpose this little organ could serve.

Researchers from the Midwestern University Arizona College of Osteopathic Medicine have worked on a study that suggests it could serve as “a reservoir” for beneficial gut bacteria.

The appendix is a worm-like strip that projects off at the crossroads of the small and large intestines, called the cecum. In the past, it has been widely viewed as a “vestigial organ” with no known present-day function for humans. None other than Charles Darwin first theorized it could be a vestigial organ from an evolutionary ancestor used to digest leaves. However, peculiarly, only a handful of mammals have the organ.

In this study, associate professor of anatomy Heather Smith and her team tracked the evolutionary history of the appendix by studying the cecum of 533 different mammals, from beavers and rabbits to common wombats and brushtail possums. Their research found it has evolved independently at least 30 separate times in several mammal lineages. Rather interestingly, once the appendix appears, it almost never disappears. This led them to the idea that it could serve some advantageous function.

Their study set out to see if ecological factors – such as diet, climate, and where an animal lives – correlated with which species have an appendix. Instead, they found that species with an appendix have higher average concentrations of lymphoid tissue, which is key in creating an immune response, in the cecum in the lower abdomen.

Research over the past few years has shown that lymphatic tissue can also foster the growth of beneficial gut bacteria. This led the team to conclude that the organ plays some role in the immune system, particularly acting as a “safe house” for helpful gut bacteria. That also means it isn’t evolving on its own as, but as part of a larger “cecoappendicular complex”.

The theory might not be set in stone, but at least they might have finally found the appendix some purpose in life.

Note: This article was originally published by Tom Hale.

Scientists Reprogram Skin Cells To Hunt Down And Shrink Brain Tumors

Brain cancers can be really tricky to treat. Some, such as glioblastomas, spread roots through the brain tissue, meaning they are often impossible to remove surgically, leading to tragically low survival rates. But researchers are working on a way to use stem cells to track down the cancer, kill it, and then melt it away. By doing this, they’ve managed to shrink brain tumors in mice to 2 to 5 percent of their original size.

The trick has already been tried before using neural stem cells to hunt down and deliver cancer-killing drugs to tumors in mice. But there is a problem: It’s tricky to get neural stem cells from humans. The safest way of doing this would be to take adult cells and then induce them in a two-step process to become neural stem cells. This, however, takes time.

“Speed is essential,” says Shawn Hingtgen, who led the research published in Science Translational Medicine. “It used to take weeks to convert human skin cells to stem cells. But brain cancer patients don’t have weeks and months to wait for us to generate these therapies. The new process we developed to create these stem cells is fast enough and simple enough to be used to treat a patient.”

The researchers found a way to speed the process up by removing one of the steps entirely, allowing them to produce the neural stem cells from adult skin cells in just four days. Usually, researchers would need to take the skin cell, induce it to become a generic stem cell, and then push it towards becoming a neural stem cell.

But by treating the skin cells with a cocktail of biochemicals, they were able to get the cells to turn straight into neural stem cells. They then tested these to see if they still had the same properties as original neutral stem cells and home in on tumors both in a petri dish and in animals models. They found they behaved exactly the same.

The final step was to see if they could somehow engineer these newly created cells to deliver drugs that are targeted at the cancer. They therefore got the stem cells to carry a particular protein that activates what is called a “prodrug”, which the researchers describe as forming a halo of drugs around the stem cell.

“We’re one to two years away from clinical trials, but for the first time, we showed that our strategy for treating glioblastoma works with human stem cells and human cancers,” says Hingtgen. “This is a big step toward a real treatment – and making a real difference.”

Note: This article was originally published by Josh Davis.

From Diet To Blood Pressure – It’s Not Just Chromosomes That Help Determine The Sex Of A Baby

The concept of being able to predict the sex of a baby during early pregnancy or even influence it by eating or doing certain things when trying to conceive has been the subject of public fascination and debate for many centuries. But surely the sex of a fetus is exclusively determined by the father’s sperm, carrying an X chromosome for girls and a Y chromosome for boys?

It turns out this is not the full story. Since the 17th century, it has been recognized that slightly more boys are born than girls. This is strange – if the sex were determined solely by chromosomes, the probability of either should be 50% and not variable. This must mean that, although the same number of boys and girls are conceived initially, more female foetuses than male ones are lost during the pregnancy.

While the mechanisms underlying these findings are not fully understood, it seems plausible that there may be underlying physiological factors in the mother that make the spontaneous miscarriage of a male or female foetus more likely – thereby influencing the likelihood of delivering a boy or a girl.

An important and fascinating study, which mapped the trajectory of the human sex ratio from conception to birth, indicated that gender-specific foetal loss varies across gestation. The authors confirmed that the sex ratio of foetuses is indeed balanced at conception. They observed an increased loss of male foetuses very early and very late during pregnancy. Female mortality, however, was higher in the remainder of the pregnancy. The net result was a greater total loss of female foetuses – consistent with observations of more boys being born. Why this is the case, however, is still a bit of a mystery.

Hormones and diet

A number of studies have observed that factors such as disasters, terrorism and economic collapse may reduce the numbers of boys born in a population. It has been proposed that stress caused by these adverse conditions results in higher levels of maternal testosterone which is associated with increased risk of miscarriage. If male foetuses are weaker than female ones, they may be disproportionately affected by this.

Indeed, studies have shown that exposure to substances that disrupt the hormonal system – including toxic man-made pollutants – have resulted in subsequent increases in female births. This has further fuelled the theories proposing that frailer and weaker male foetuses have a survival disadvantage in times of overwhelming environmental stress.

It remains unclear whether high maternal concentrations of testosterone play a role in these processes. It is also uncertain whether adverse social, economic and political situations result in higher androgen levels in mothers at all.

The influence of maternal diet on offspring sex ratio has also been widely debated. Studies in rodents and mammals have indicated a higher likelihood of males being born from well-fed, healthy mothers. In humans, however, there have been conflicting results, with higher proportions of males being born both in women with high energy intake prior to pregnancy, but also during famine and war.

Blood pressure

Meanwhile, a recent study found a link between blood pressure and the sex of the baby. The research evaluated 1,411 Chinese newly-married women at about 26 weeks before conception. It identified that systolic blood pressure was almost 3mmHg higher at this time in mothers who would go on to give birth to a son. This held true even after they adjusted for factors including age, education, BMI, smoking, cholesterol and glucose.

The likelihood of delivering a boy rose progressively with higher pre-pregnancy systolic blood pressure and at a reading of 123 mmHg, the chance of having a boy was 1.5 times higher than that of having a girl. Importantly, systolic blood pressure before pregnancy was the only independent predictor of having a male baby. Notably, these differences in blood pressure between mothers of male and female babies were not observed during pregnancy.


It is unclear how blood pressure may affect offspring gender. The processes involved in formation of the placenta appear to be different dependent on the sex of the foetus. A woman’s circulation has to undergo important adaptations in early pregnancy to accommodate increased blood flow to the foetus and it is possible that maternal blood pressure may therefore affect whether you are more likely to lose male or female foetuses.

While the findings of this study are extremely fascinating, there are a number of important limitations. The study was performed in young, healthy Chinese women with normal weight and may not be applicable to other populations. Moreover, the findings do not indicate a causal link but merely an association. In other words, it has not been demonstrated that a woman can increase her chance of delivering a boy by raising her blood pressure. It is more likely that the systolic blood pressure measurement before pregnancy is an indicator of the mother’s underlying physiology and ability to carry a baby of a specific gender. Either way, only more research can provide reliable answers.

All this research has important clinical and ethical implications. In particular, there’s a risk that women in cultures where the birth of one sex over the other is preferred engage in dangerous experimentation with trying to change blood pressure, diet or hormonal balance prior to pregnancy.

NOTE: This article was originally published on The Conversation by Kristien Boelaert, Reader in Endocrinology, School of Clinical and Experimental Medicine, University of Birmingham. Read the original article.


People Living Near Busy Roads Found To Have Higher Rates Of Dementia

We know that breathing in air pollution from major roads is bad for our lungs, but it may be impacting people in another way. A new study has found that people living in close proximity to busy roads have higher rates of dementia. Currently, it is unclear whether the air pollution is the direct cause for higher rates, but the findings have been described as “interesting and provocative”.

Published in The Lancet, the study assessed close to 2 million people living in Canada over an 11-year period. They found that people living within 50 meters (164 feet) of major roads, had higher rates of the neurological condition, with as many as 11 percent of cases potentially caused by the high levels of traffic. The rate of diagnoses then dropped off the further from the roads people were living.

From age and genetics to diet and smoking, there are multiple risk factors that are thought to contribute to the development of dementia. The researchers accounted for many of these, including obesity and education levels, meaning they are unlikely to explain the link, but that does not necessarily mean that traffic or air pollution is the direct cause of the increased rates observed, though it does raise interesting questions.

“Studies like this are valuable in revealing new factors that could be implicated in Alzheimer’s disease and other dementias, and opening new avenues for further research,” said Dr Davis Reynolds, chief scientific officer at Alzheimer’s Research UK. “This study has identified major roads and air pollutants from traffic as possible risk factors for dementia, a finding which will need further investigation before any firm conclusions can be drawn.”

The research adds to the growing concerns about the impact that air pollution is having on an increasingly urbanized population. With over half of the world now living in urban areas, the effect breathing in such dirty air is having on public health is becoming a serious concern.

Last year, it was reported that between three and five million people are dying prematurely due to air pollution, and with the urban population only expected to expand, this figure is sure to rise. Most of these deaths are down to respiratory problems and lung cancer, but the fact that dementia may now also be implicated adds another layer to the situation.

How governments will respond to this is growing issue is still not clear, though some cities have taken bold steps, with Athens, Madrid, Paris, and Mexico City vowing to ban all diesel cars by 2025, while urging others major urban centers, such as London, to follow suit.

NOTE: This article was originally published by Josh Davis.