Recent Developments

A few months ago I was somewhat surprised to see a news story about scientists who had managed to get the natural balance just right to be able to support the growth of lamb foetuses in plastic bags (“BioBags”). This was not like anything I expected to see in this half of the century, and sounded like something from a science fiction movie, so you can understand my excitement at this achievement. In this blog post I will aim to explain the challenges the scientists faced in trying to get this system to support life and what this could mean in the future, not only for animals but for humans too.

The most obvious challenge when designing the Biobag was what to grow the foetus in. Amniotic fluid for a foetus is not only a cushion, protecting it from knocks and bumps, but it aids in bone and limb growth, and supplies the foetus with vital nutrients. Some also say that swallowing amniotic fluid helps to foster antimicrobial protection[1] and to develop the foetus’ gastrointestinal system[2]. Therefore, it is crucial to get the volume and composition of artificial amniotic fluid right. Complicating this is the fact that these conditions change throughout gestation to match the foetus’ stage of growth and needs.

The synthetic amniotic fluid used in the Biobags is a neutral electrolyte solution composed of hydrogen carbonate, sodium, chloride, potassium and calcium salts. These are all nutrients which the foetus needs to grow and develop. Although the initial experiments just used this simple electrolyte solution, the scientists’ future research will focus on improving and optimising the solution to be used in the Biobags [3].

Another challenge was how to get oxygen and nutrients to the foetus and remove any waste produced. Placental transfer is vital for the gas exchange and excretion of waste for the foetus. By inserting cannulas into the major veins and arteries in the lamb’s umbilical cord, these blood vessels can be attached to a filtering and exchange system for gases to be transferred to and from the lamb’s body[3]. This, however is not done by a man-made pump, but instead by the natural pump that exists in all mammals’ bodies; the heart. Using the foetal heart to drive the circulation instead of an artificial pump has many advantages, including a natural regulation of blood pressure, and simplicity – this is also closer to the natural situation. The heart of the foetus is able to pump the blood through the external gas exchange system at the perfect pressure to maintain the correct blood gas content but not too high that the blood vessels of the umbilical cord or the umbilical cord to machine interface are under threat of rupture.

However, the volume of the oxygenator is crucial. If too high or low a volume, then the foetus will become haemodynamically unstable (an instability in the flow of blood around the body[4]) and the system will not be able to deliver sufficient oxygen to the foetus.

Infection can be lethal to any foetus, even those cushioned safely inside a maternal uterus. However, this is a major consideration for foetuses in Biobags. The scientists lost many foetuses in their research because of sepsis (an infection), but have significantly reduced losses by having a ‘closed’ system with microbial filters and sterile access ports fitted for any addition of fluid or suction of meconium (faecal waste produced by the foetus).

Biobags have successfully grown infant lambs from a stage that would be equivalent to extremely premature human infants for up to 4 weeks. This may not sound like a long time, but this extra developmental time can be the difference between life and death or normal brain/lung function and life changing damage to human infants. It is also important to note that this 4 week period was not due to mechanical failure or a mishap in the system, the experiment had to be terminated at this time because of animal protocol limitations. The foetuses could be sustained in Biobags for much longer.

The scientists hope that Biobags could be used in the future to help human infants of just 23-25 weeks’ gestation[5] to have better outcomes, and to help treat conditions such as growth retardation caused by placental insufficiency. The trials for this could occur as soon as 3 years’ time. Although there may be some psychological barriers to overcome for parents seeing their baby ‘in a bag’, the possible applications of this breakthrough technology are potentially limitless, and truly in the realms of science fiction.

[1] BIOLOGY DICTIONARY. (2017) Amniotic Fluid. [Online] Available from: https://biologydictionary.net/amniotic-fluid/ [Accessed: 15th September 2017]

[2] SANGILD, P. T. et al. (2003) Ingestion of Amniotic Fluid Before Birth: Does It Improve Intestinal Function? [Online] Available from: https://actavetscand.biomedcentral.com/articles/10.1186/1751-0147-44-S1-P109 [Accessed: 15th September 2017]

[3] PARTRIDGE, E. A. et al. (2017) An Extra-uterine System To Physiologically Support The Extreme Premature Lamb. [Online] Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5414058/ [Accessed: 17th September 2017]

[4] CHEGG. (2017) Signs And Symptoms Of Hemodynamic Instability. [Online] Available from: http://www.chegg.com/homework-help/definitions/signs-and-symptoms-of-hemodynamic-instability-14 [Accessed: 17th September 2017]

[5] TAYAG, Y. (2017) How a Plastic Bag Became a Womb for Premature Lambs. [Online] Available from: https://www.inverse.com/article/30836-premature-lamb-artificial-womb-uterus-plastic-bag [Accessed: 17th September 2017]

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Mind Over Matter

imageTaking a break from my monthly blog post about the fantastic Natural History Museum, I have decided to discuss one of my favourite and perhaps more controversial biological topics – the placebo effect. I am a massive fan of mental strength over physical prowess (I’m not the most athletic shall we say, so it works for me) and the placebo effect demonstrates just how strong the human mind can be. As perhaps one of the more complex of all of our organs, I’m going to talk about the brain and its role in numbing pain, reducing physical symptoms, and sometimes even curing disease.

Pain relief
This is one of the more obvious uses of placebos, as everyone has heard of someone withstanding cutting off a limb without anaesthesia in order to save their life; there has even been a film in which a man becomes trapped for 127 hours, only being released after cutting off his own hand. However, the more interesting side to this story is how we could potentially harness this effect in order to treat those with addictions to painkillers.

The statistics are shocking, with nearly 7,000 visits to A&E and 44 deaths each day caused by prescription painkiller addictions in America in a single year[1]. Pain clinics and monitoring prescription patterns are struggling to reduce this, so what if a solution could be found in a more unconventional place? Prescription painkillers have been put to the test, and some studies have shown that they do not work as well in bland, non-branded packaging [2], and also that their effects are reduced when the patient is unaware that they are taking them [1]. Additionally, the placebo effect can also have the opposite outcome – where no drugs are administered, placebo painkillers have been seen to affect the pain-related areas of the brain, and even stimulate the release of endorphins (which are pain relieving chemicals that the body produces).

Expectations play a great role in this effect. This is where ‘mind over matter’ plays a more prominent role. During a study, three groups of patients were given a placebo. One group had no expectation of analgesia (pain relief), another group had a positive expectation of analgesia, and the third had a negative expectation of analgesia (in the sense that they expected the pain to worsen). When the patients were asked to rate their pain, the patients expecting a positive result experienced twice the analgesic effect than the patients with no expectation of pain relief. Also, the patients expecting a negative result experienced no pain relief at all [3]. And this leads me quite nicely onto my next point for discussion.

The Ceremony
Placebos rely quite heavily on the art of pomp and ceremony, and this is quite clear to see when the placebo ‘form’ is examined in more detail.

As aforementioned, the packaging of a placebo makes a huge difference in the level of expectation and therefore the experience of the enclosed pill. On reading “Bad Science” by Ben Goldacre, I was interested (but perhaps not surprised) to read that patients responded better to placebos found in bright and flashy, branded packaging as opposed to bland, neutral boxes. An even greater effect was seen when patients were given aspirin in differing packaging.

However, external packaging is not all that matters when packaging a placebo. The colour of the pill itself has been found to play a role in this ever so fascinating and developing effect. For a drug called Oxazepam, its effects differed when the tablets were differently coloured. In a green tablet form it was better at treating anxiety, whereas the same drug was found to be more beneficial at treating depression when yellow. Colours have been assigned meanings by society, and these societal norms are influencing the way we perceive the world. Blue for sedatives, pink for stimulants. This was seen to be the case when a group of college students were given a placebo, told to be either a sedative or a stimulant. Those given pink pills experienced higher maintained concentration levels than those given blue pills. Two pills were also observed to have a greater effect than one (side effects included) [2].

This explains the pomp, but what about the ceremony? Well, again, this relates back to what we perceive to be ‘more effective’. The best example of this is the vaccine. In three separate experiments, pills have been out done by the salt-water injection. Not because sugar pills have any less of a biological effect than salt-water, but purely because it was seen as a more dramatic treatment. Much the same was seen when a sugar pill was put up against an acupuncture style ‘ritual’ treatment [2]. Ceremony wins.

Ethics
This is perhaps the more controversial side of any placebo discussion. Is it ethical to supply a patient in pain, or with a disease, a placebo knowing that it has no active ingredient to treat the ailment? The answer is no. At least if you don’t discuss it with them first.

In a recent meeting of the school’s vets and medics society, we discussed in some detail the ethics behind full disclosure and some scenarios in which it was difficult, from an ethical stand point, to determine what exactly was the best way and thing to tell your patient. I was very much on Team Full Disclosure and my opinion hasn’t changed. When it comes to a patient’s health, they have a right to know exactly what is going on, which is why my whole viewpoint on the placebo effect changed when I discovered this next fact.

The placebo effect will have a very limited real life application if the patient must remain in the dark about the contents of the mysterious looking pill sat in front of them in order to feel its effects. It’s unethical. However, the placebo does not just work because the brain is tricked into thinking it has received a drug. Patients have been fully aware that they are taking a placebo and have still experienced the same effects as if they had been unaware. In a study, 80 patients suffering from irritable bowel syndrome (IBS) were split into two groups. One group was given no treatment, and the other given a placebo. The placebo group were told that they were being given a placebo, and that meant that all the pills would contain was sugar. To avoid confusion, ‘placebo’ was even printed on the bottle. Defying all expectation, the placebo group doubled the average rate of improvement to that expected from the most powerful IBS medications [4]. Presumably, this has something to do with the ritual of taking a pill, whether it contains medication or not, and the mind being deceived by the mere action. However, the sheer size of the effect experienced was somewhat incredible.

Conclusion
The placebo effect is a wonderful demonstration of the power of the human mind, which I have always been deeply fascinated by. The social perceptions of colour and packaging, along with the ritualistic ceremony linked to how our brains not only receive medicine but also see the world is brilliantly clever, but also a little terrifying – perhaps the role of society in our lives is not as small as we once thought! I hope you have found this little insight into the placebo effect as interesting as I have, and I hope you now realise how truly amazing your brain is.

 

[1] MARCHANT, J. (2016) A Placebo Treatment for Pain. [Online] Available from: https://www.nytimes.com/2016/01/10/opinion/sunday/a-placebo-treatment-for-pain.html?_r=0 [Accessed: 30th January 2017]

[2] GOLDACRE, B. (2010) Bad Science. 1st ed. New York: Faber and Faber.

[3] NOVELLA, S. (2011) Placebo Effect for Pain. [Online] Available from: https://sciencebasedmedicine.org/placebo-effect-for-pain/ [Accessed: 30th January 2017]

[4] JHA, A. (2010) Placebo effect works even if patients know they’re getting a sham drug. [Online] Available from: https://www.theguardian.com/science/2010/dec/22/placebo-effect-patients-sham-drug [Accessed: 30th January 2017]

A Trip Which Sparked Curiosity (Part 3)

A Burst Of Colour

imageThe Christmas festivities are well under way, and we all know how colourful this season can be. Red, green, yellow, you name it, chances are there is a decoration in your house of that colour. Thinking about the sheer variety of colour I am surrounded by at the moment led me to dedicate my next post to a smaller, and often forgotten realm – the world of the invertebrates.

Christmas to insects isn’t the same, for many insects can only see the higher part of the visible light spectrum and part of the ultraviolet light spectrum. An exhibit in the Natural History museum showed what some flowers could look like through an insect’s eyes, and I was curious about what difference in anatomy caused this interspecies variation in vision.

It’s all about the receptors

Many insects that can detect ultraviolet light have eyes which contain ultraviolet light receptors which aren’t present in human eyes. Human eyes contain three types of photoreceptors, we are trichromatic; red, blue, and green [1]. When light enters the eye, its wavelength determines whether it is absorbed by these receptors, and the combination of signals produced by the photoreceptors due to the light absorbed is what determines which colour the brain perceives (as a quick side note; discussing colour perception is very theoretical, as, the sensors stimulated and colour of light absorbed can be scientifically proven, however, how the brain of the organism interprets those signals is impossible to state with 100% accuracy. Predictions can be made, but perception of colour is in the eye of the ‘bee-holder’ only after all [2].).

imageInsects are trichromatic also, however they do not possess the receptor which absorbs red light. Instead, insects possess the ultraviolet light receptor, leading to many invertebrates being unable to sense red light but instead being able to sense light towards and in the ultraviolet spectrum. Each of the insect’s prismatic lens containing units (or ommatidia [3]) contains eight light detecting cells; four respond to yellow-green light, two respond to blue light, and the other two respond to ultraviolet light [2]. This fact has forced flowers to develop petals which are attractive to insects not only in the visible light spectrum, but also in the ultraviolet light spectrum.

One hundred and eighty

imageWhen looking at many petals in the visible light spectrum, they may seem drab and a bit boring to you and me, however, when placed under an ultraviolet lamp, or photographed with an ultraviolet camera, these petals reveal a hidden world. Patterns, like dart boards, suddenly appear and offer a small glimpse into the world of the invertebrate. Vibrant colours illuminating the pollen rich areas of the flower act as a target for the insects flying overhead [4]. They have adapted so their petals are not only attractive to the human eye in the visible spectrum, but they exploit the ultraviolet sensing ability of the insects to become highly practical in their marketing strategy. No beating around the bush, if the insect wants nectar, it knows exactly where to find it. With a precise flutter of the wings, the insect hits the bullseye, receiving a sugary reward.

Conclusion

The photoreceptors present in the eye is what makes all the difference when perception of colour is involved. Without the relevant receptor, an entire spectrum of colours is inaccessible and a world is hidden to us. Think about how different Christmas could be with just a simple receptor missing.

 

[1] HORSE ARMOR. (2016) Insect vision. [Online] Available from: http://www.horsearmor.net/pages/Insect-Vision.html [Accessed: 23rd December 2016]

[2] RIDDLE, S. (2016) How Bees See And Why It Matters. [Online] Available from: http://www.beeculture.com/bees-see-matters/ [Accessed: 23rd December 2016]

[3] [Online] Available from: http://cronodon.com/BioTech/Insect_Vision.html [Accessed: 23rd December 2016]

[4] STARR, B. (2013) Hidden Patterns: How A Bee Sees The World Of Flowers. [Online] Available from: https://www.visualnews.com/2013/04/08/hidden-patterns-how-a-bee-sees-the-world-of-flowers/ [Accessed: 23rd December 2016]

A Trip Which Sparked Curiosity (Part 2)


The Infamous Horned Bill – Combining Physics And Biology In One Beak

Continuing on my travelimages around the Natural History Museum, I came across an odd shaped beak, cut in half. The main beak was structured how one would expect it to be structured – a curved shape with a spiderweb of bone fibre strands inside – however, the addition of, what I now know to be called, a casque confused me. This hollow mound atop the beak ignited the curiosity inside me, leading me to write my second post in this series about the gorgeous Rhinoceros Hornbills, and more importantly, the more practical functions of their striking beaks.

The Casque

The normal part of the beak is predominantly used how every other beak is used, nothing much unusual to report here, so rather than take you all through the “boring” part of the beak, I decided to only discuss the more extraordinary casque.

Acoustics

The main theory about the function of this weird structure is that it is used almost like a resonance chamber[1], to amplify the sound of the Rhinoceros Hornbill’s call.

The casque is a perfect shape to allow a certain number of whole sound waves to fit into it. This length is different for each species as their calls are different pitches, and the sound waves produced, therefore, have different wavelengths. When the bird then calls, some of the sound waves produced enter the casque. As more sound waves enter, the crests of these waves line up and produce a resultant wave with the combined amplitude of the initial waves. This has a resonating effect and the sound is therefore amplified.

Reinforcement

The casque is said to have reinforcement properties as well. Not only does it add structural integrity to the beak, but also adds weight to make the beak a more effective hammer[2], which is useful when cracking open the tough exoskeletons of insects, and when the female and offspring break out of the enclosed nest (see ‘brief side note’ below).

Another use for this splendid casque is in aerial jousting [3] – a competition males engage in for territory and mates – which is pretty much exactly what it sounds like. Two males fly at each other at great heights and clash casques, so the reinforcement comes in handy; protecting the birds from major injury.

Sexual Attraction

The casque not only has purely practical purposes. A large element is attracting a mate. It is the casque in Rhinoceros Hornbills which exhibits sexual dimorphism – the size of casque differs between male and female[3]. This differs between species; in some species the males have bigger casques, but in others the roles are reversed, and some species are even monomorphic (only one size of casque is present). However, the interspecies differences are driven by sexual selection pressures, as some species’ casques may have evolved to allow them to excel in other areas.

The casque’s colours are also important in sexual attraction. When the Hornbills are born, their beaks and casques are white, like our fingernails. However, as they grow older, they rub their beaks against an oil gland just underneath their tail feathers, imagesecreting an orange oil onto the beak. The cumulative applications of this oil are what create the tremendous bursts of colour on the beaks. This allows individuals to recognise each other and sometimes is helpful in visual signalling as well [2].

Although not always the case, sexual dichromatism can occur as well. As I discussed in my previous post about the King of Saxony bird of paradise, sexual dichromatism is something which occurs in most birds. Some species of Hornbills exhibit this dichromatism through the colours and patterns created on their casques [2]. These factors all combine to create the perfect display in order to look as attractive to the female as possible.

Brief side note

As I mentioned previously, the females and their offspring have to break out of the enclosed nest which the Hornbill parents create. I thought I ought to discuss this further, not least because I find it a particularly fascinating element of the Hornbill’s behaviour.

Once the female and male have mated and the female is ready to lay her eggs, the pair find a hollow tree cavity, build a nest, and proceed to seal the female inside. They do this by creating a imagepaste made from fruit, faeces, and mud, squashing this through their beaks against the side of the cavity entrance. The pair completely seal the cavity except from a slit which is left for the male to pass regurgitated fruit through to keep the female alive while she sits on her eggs, and the offspring alive once they have hatched until they are ready to leave the nest. The female will also use this slit to expel faeces and uneaten food, in order to keep the nest clean [4].

Three months after the eggs have been laid, the female breaks out of the nest. Working with her life partner, she reseals the cavity so the offspring can be kept safe for another three months; until they are able to break out of the nest by themselves. Both parents take care of the offspring until this point [4].

Conclusion

Many of us may have grown up seeing these beautiful birds in zoos and on the TV, so the Rhinoceros Hornbill’s beak may be something that we are used to seeing, however, I hope that this post has given a bit more of an insight into the adaptations which make this bird’s beak perhaps one of the most interesting. I have been surprised at the level of sophistication that the seemingly useless mound that is the casque has demonstrated as a structure, delving briefly into the world of physics and then returning to the familiar realms of biology to fully discover the functions of the beak’s most peculiar feature.

 

[1]WORLD LAND TRUST. (2016) Rhinoceros Hornbill. [Online] Available from: http://www.worldlandtrust.org/education/species/rhinoceros-hornbill [Accessed: 18th November 2016]

[2]JACKSON, T. (2013) What is the function, if any, of a hornbill’s casque? [Online] Available from: http://africageographic.com/blog/what-is-the-function-if-any-of-a-hornbills-casque/ [Accessed: 19th November 2016]

[3]NAISH, D. (2014) The Splendid and Remarkable Anatomy of Hornbills [Online] Available from: https://blogs.scientificamerican.com/tetrapod-zoology/the-splendid-and-remarkable-anatomy-of-hornbills/ [Accessed: 24th November 2016]

[4]NATIONAL AVIARY (2016) Rhinoceros Hornbill [Online] Available: https://www.aviary.org/animals/rhinoceros-hornbill [Accessed: 27th November 2016]

A Trip Which Sparked Curiosity (Part 1)

The King of Saxony’s Crown

 Very recently I visited the Natural History Museum in London for the first time in six years. I was immediately transported back to the last time I was there, completely filled with awe and wonder.

Investigating many of the exhibits sparked my curiosity and so I thought I would share with you, in a series of posts, what I found interesting and the further information I have discovered as a result of my curiosity.

The King of Saxony Bird of Paradise

I am going to start with one of the most peculiar of my discoveries; Pteridophora alberti, or more commonly known as the King of Saxony Bird of Paradise. What caught my eye about this tiny bird was the huge pair of head wires attached above its eyes which are, in most cases, double the length of the bird itself.[1]head-wires

These head wires consist of a shaft with fused barbs down one side, which have been greatly modified for their purpose; to attract a mate. As many of you may already know, in the animal kingdom, success is measured by the number of genes an individual passes down to the next generation, via the offspring, and the male King of Saxony Bird of Paradise has a very unusual way of increasing his chances of success.

The Dance of Love

A mating dance is not uncommonly associated with particular species of birds, however the mating dance of the King of Saxony Bird of Paradise is second only to that of the Magnificent Riflebird (which, let’s face it, isn’t a surprise based on its name). While many birds, like the Magnificent Riflebird and the Superb Bird of Paradise (again, another case of an appropriately named bird) show off their genetic prowess by puffing up their feathers and startling the poor female with bright flashes of colour[2], the King of Saxony Bird of Paradise takes a different approach.

A lonely male sits on a branch high in the canopy and waits for a female to pass by. 2ndWhen one catches his eye, he flies down to his chosen courtship branch and prepares for the performance.[1] He gets excited. His first display is a bit of a warm up, he bops up and down on his branch rhythmically, trying to attract the much sought after attention of the female, competing with other males in proximity. Increasing in emotion, the male King of Saxony then begins his call. Starting with a low buzz, his mating call not only rises in volume but also in pitch, eventually building to an incredibly ear-piercing screech, which, combined with several clicking sounds, will hopefully win over the female.

However, the female has not yet been wooed, and the spectacle is only just beginning. As the now fully enthused male King of Saxony reaches the climax of his dance, he puffs up his feathers and his head wires begin to rise. The sound of buzzing heightens, the magnificent head wires are now extended above the top of his head. Screeching begins, the feathers on his head puff up, and he brings his head wires perpendicular to the sides of his head. With a screech that gives the rainforests of Papua New Guinea its characteristic sound, the male King of Saxony waves his head wires in a well rehearsed manner, as to make the female fall instantly in love with him.

The Evolutionary Success

This routine has been practised and perfected and, subsequently, passed down through the generations, but it has not always been like this.

In the forests of Papua New Guinea, the climate is warm, food is abundant (at least for the King of Saxony Bird of Paradise) and predation is at a relatively low level. Therefore, the evolution of the King of Saxony has not been guided by the need to thermoregulate, or hunt, or even blend into surroundings [3], but by its ability to attract a mate. The female King of Saxony Bird of Paradise finds the male’s outrageous head wires and ear-piercing screeches hugely attractive (whatever floats your boat I guess), so that is what has steered evolution to produce this incredibly interesting looking bird. For a male King of Saxony Bird of Paradise, the longer your head wires and louder your call, the more likely you are to succeed in passing your genes to the next generation, and the lack of parental help the males give the females, means the males can continue to give their genes to several females in a year, further increasing their success.

Furthermore, it is also as a result of sexual selection that the female counterparts of3rd brightly coloured male birds are always so dull in comparison (sexual dichromatism). Females are picky when choosing a mate; they want the best genetic package for their offspring, so when it comes down to it, what the females look like doesn’t matter to male birds, as long as they get to pass down their genes. Females want the brightest, best looking and sounding male to hopefully pass strength, resilience and attractiveness down to their offspring, so the chances of survival are much greater. It has also been scientifically proven that, in birds, there is a positive correlation between brighter colours and better health.[4] Females also need to be able to camouflage themselves when sitting on their eggs, which could be another explanation for sexual dichromatism.

Conclusion

In conclusion, what I first thought was just a small bird with a big hair issue, is actually an incredibly interesting example of sexual selection, and just goes to show how far evolution will go to ensure the highest chance of success in the animal kingdom.

[1] BIRDS OF PARADISE PROJECT. (2016) King Of Saxony Giant Head Wires. [Online] Available from: http://www.birdsofparadiseproject.org/content.php?page=77 [Accessed: 24th October 2016]

[2] ARKIVE. (2012) Superb bird-of-paradise. [Online] Availabe from: http://www.arkive.org/superb-bird-of-paradise/lophorina-superba/image-G129246.html [Accessed: 24th October 2016]

[3] LARSON, S. (2016) The King of Saxony Bird-of-Paradise’s Courtship Freakout. [Online] Available from: https://www.junglesinparis.com/stories/the-king-of-saxony-bird-of-paradise-s-courtship-freakout [Accessed: 26th October 2016]

[4] SCIENTIFIC AMERICAN. (2016) Why are male birds more colorful than female birds? [Online] Available from: https://www.scientificamerican.com/article/why-are-male-birds-more-c/ [Accessed: 26th October 2016]

Influenza – The Virus That Gets Away With Murder

The ‘flu season is quickly approaching, but I bet most people don’t have it marked in their diaries because no one dies of the ‘flu anymore, right? Wrong! Every year around 8,000 people die of the ‘flu in Britain, and that number is slowly rising. [1] This year, in a three week period after January the 23rd, 28,000 people died of the ‘flu – in the same three week period for the last five years the average has been 21,000 – this is a huge increase of a third. [2]

What does this murderous virus look like?Image result for influenza virus

Influenza, aka the ‘flu’, is caused by a virus which under an electron microscope looks like a ball of strands of nucleic acid enclosed in a protective coat that is spiked with antigens. This gives it the very iconic shape that all biologists associate with this underestimated virus.

What symptoms does the ‘flu virus cause?

In the next few months, people all over the country will be complaining to their doctors (or friends and family) that they have a fever, sore throat, headache, and are really tired. [3] Little do these people know, but they have probably been infected with the ‘flu. These symptoms are due to the body’s reaction to the virus infiltrating the cells in the throat, hijacking the DNA into producing more ‘flu viruses, and these viruses violently bursting from the infected cells. [4]

The sore throat experienced is due to the violent nature of this bursting from the cells. Many of the throat cells are damaged as this happens, and each generation of viruses infiltrates more and more cells and they reproduce rapidly.

Headaches can be due to the body producing mucus in the nose to try to stop any more infectious microorganisms entering the body. This mucus blocks the sinuses, which increases the pressure inside the head.

A fever is a very clever defence mechanism because the high temperature is not so high that it permanently damages (or ‘denatures’) human enzymes, but is high enough to denature the virus’ enzymes – slowing it down enough to allow the body’s white blood cells to swoop in and destroy it.

Symptoms of the ‘flu are very similar to the symptoms experienced during a rhinovirus infection (the common cold) but ‘flu symptoms are actually much worse. Many people, therefore, are tempted to dismiss ‘flu symptoms as a bad cold. This is actually their second mistake, but I’ll come back to the first mistake a bit later.

So why now?

Why is the ‘flu season so late in the year? Most diseases pop up in the summer months when the temperatures are warm and humid, and parasites, bacteria, and viruses can thrive…. but the ‘flu virus is weird – it prefers the winter months when temperatures are cold and all life seems to slow down.

A study carried out in October 2007 showed that guinea pigs were more likely to infect other guinea pigs in colder temperatures.[6] In addition, the ‘flu virus was also able to stay alive for different amounts of time in different conditions.

Why should this be? In cold temperatures, the protective coat on the virus hardens until it becomes rubbery. [5] This gives it the protection it needs to not only spread from person to person, but also to survive for 22 hours more than if temperatures were hotter. As temperatures rise, at around 90 degrees Fahrenheit the virus’ protective coat melts into a liquid and the virus then has very little protection from the elements. In this state, the virus is only able to stay alive for 1 hour. [6] It would seem a poor evolutionary step to develop this way, but the virus must give up its protective coat so that it can infect the host – the virus is only able to infect cells when its coat is in this liquid state.[5]

How does the virus travel from person to person?

The spread of this virus is by droplet. When an infected person coughs, sneezes or even talks, the virus can be projected from the mouth into the air, contained in droplets. In cold conditions, its outer coat protects the virus from some soaps and external conditions that could damage it. However, once a floating, infected droplet has been inhaled or swallowed by another person, the virus takes only 1 to 4 days to cause symptoms. [3]

You’ve got the ‘flu – what now?

If symptoms are not severe, keeping warm and hydrated at home can often be enough, with a few pain medications for aches. If the symptoms are severe, there are antiviral treatments available that stop the virus multiplying and help the body to battle the infection. [3]

So, what is the first mistake people make?

The first mistake many people make when it comes to the ‘flu is not taking it seriously enough. A ‘flu vaccination is available and should be taken by elderly people, young children, pregnant women and the immunosuppressed, as they may not be able to battle the virus by themselves. Unfortunately, the vaccination itself can give symptoms of the ‘flu because it contains live virus particles, but the strain of ‘flu causing infections may be different each year, and so it’s sensible to have the vaccination repeated each year with the current version of the virus so that your immune system is ready.

Can the ‘flu be prevented?

The good news is that preventing the spread of the ‘flu is simple. Washing hands regularly with soap is very important, as it removes any virus particles from your hands so they can’t be transferred to surfaces. [7] Staying away from infected people (or non-infected people if you have symptoms) and being very careful with hygiene are also crucial in the battle with the ‘flu.

 

The influenza virus kills thousands of people each year and yet most people consider it to be only mildly worse than the common cold. This ‘flu virus really is the virus that gets away with murder and if it is possible to minimise the amount of people who die from this virus yearly by preventing the spread of it, I think we should try.

 

[1] PUBLIC HEALTH ENGLAND. (2014) Public Health England and the NHS prepare for unpredictable flu season. [Online] Available from: https://www.gov.uk/government/news/public-health-england-and-the-nhs-prepare-for-unpredictable-flu-season. [Accessed: 26th October 2015]

 

[2] CHRIS COOK. (2015) Death rate up by a third in January. [Online] Available from: http://www.bbc.co.uk/news/health-31124320 [Accessed: 26th October 2015]

 

[3] NHS CHOICES. (2015) Flu. [Online] Available from: http://www.nhs.uk/Conditions/Flu/Pages.aspx [Accessed: 26th October 2015]

 

[4] RUSSEL MCLENDON. (2013) How does the flu work? [Online] Available from: http://www.mnn.com/earth-matters/translating-uncle-sam/stories/how-does-the-flu-work [Accessed: 26th October 2015]

 

[5] NIH NEWS. (2008) NIH Scientists Offer Explanation for Winter Flu Season. [Online] Available from: http://www.nih.gov/news/health/mar2008/nichd-02.htm [Accessed: 26th October 2015]

 

[6] SITNFLASH. (2014) The Reason for the Season: why flu strikes in winter. [Online] Available from: http://sitn.hms.harvard.edu/flash/2014/the-reason-for-the-season-why-flu-strikes-in-winter/ [Accessed: 26th October 2015]

[7] CENTERS FOR DISEASE CONTROL AND PREVENTION. (2015) CDC Says “Take 3” Actions to Fight The Flu. [Online] Available from: http://www.cdc.gov/flu/protect/preventing.htm [Accessed: 26th October 2015]