Epidemic!

WARNING: The United States is in the midst of an epidemic! This outbreak has been cited as the cause of more than 9% of deaths during the first week of the new year. Nearly all fifty states have reported widespread infection and hospitalization rates have spiked. But in the words of CDC Influenza Division Director Dr. Dan Jernigan, “yes, [we’re] definitely in an epidemic, but that happens every year in the United States and in the Northern Hemisphere with influenza.” 

Yes, that’s right. This epidemic that America is struggling with just so happens to be the same one we that face year after year: the flu. 

Yet again, we come to the question: how is something no more than 120 nanometers across able to wreak so much havoc? Our culprit is another small RNA virus: influenza! 

Image courtesy of Kat Masback.

But influenza is certainly not the shrimpiest kid on the block.  Instead of having just a single gene like a rhinovirus, it has upgraded to a whopping 10 genes, and it has a bonus feature: an envelope! Much like the plasma membrane of our own cells, a viral envelope resembles a bubble of fatty molecules and serves as another defense for the virus. 

The influenza envelope has two surface proteins embedded into it. Known as H and N or hemagglutinin and neuraminidase respectively, these proteins play crucial roles in helping the virus grab onto cells in our airways and in defining our immune response. In fact, they are so important that we name strains or forms of influenza according to them! 

For example, the strain we have seen this winter is H3N2, aka. a form of the influenza virus with the third type of H and the second form of N. 

But more broadly, the classification of the human influenza virus is as simple as A, B, C! Influenza A is broken down into the H and N subtypes we discussed above, and it, along with its accomplice Influenza B, causes the seasonal outbreaks we look forward to each and every winter. 

But it seems that after more than 50 years of fighting this virus, we should have figured it out by now! 

But, influenza A and B are fickle and indecisive, making it difficult for us to pinpoint them. These viruses just can’t stand still, continuously shifting via a process called antigenic drift. 

Antigenic drift is a gradual change where small mistakes in copying the viral genes cause minuscule tweaks in the identity of the new virus particles produced. These mutations might not make immediate drastic transformation, but with time, they stack up. 

Antigenic shift is the big brother to antigenic drift and the big bad behind the Swine Flu (H1N1) panic and pandemic of 2009. Remember way back to elementary school when H1N1 came from nowhere? All of the sudden, everyone had to get a swine flu shot, and school halls were riddled with rumors about how swine flu killed people! A titanic change had occurred in the flu virus, creating entirely new types of H and N that we had never seen before. Antigenic shift may be rare, but it is undoubtedly terrifying! 

Either way, since influenza can’t seem to make up its mind about what surface proteins will be in style this winter, we just have to wager an educated guess about what to include in the annual vaccine. As a consequence, vaccines might not always be entirely effective. (This is not to say that you shouldn’t get the flu shot; rather it is an essential preventative measure required to stay healthy!) 

This flu season, in particular, is the most intense since the Swine Flu in 2009. But, why is the flu so severe this year? 

Image courtesy of Agência Brasília. 

The specific strain of influenza A that is widespread throughout North America right now is known as H3N2. And according to Live Science, H3 strains of influenza tend to cause more serious cases of the flu. Vaccines have also been shown to be only 30% effective against H3 strains of the virus, relative to the typical 50-60% efficacy against other forms of influenza. 

In other words, this year especially, you must be sure to get a flu shot – its not too late – and to see a doctor within 48-hours of seeing symptoms of the flu. Although flu symptoms do tend to resemble those of a cold, the flu comes on more suddenly and often involves a high fever (above 101°F). 

Taking precautions similar to those for avoiding the common cold (check out last week's post), can also help keep the flu away! As always, best of luck staying healthy.

The Most Wonderful Time of the Year!

Not quite sleigh bells and mistletoe anymore.

Soprano sneezes blend with the deep, rattling timber of chest coughs as the frantic staccato of sniffling echoes through the tin can that my 300-student chemistry lecture has been crammed into like sardines. Some glumly clutch tissues while others cling to XL bottles of hand sanitizer, eyes wide and paranoid, knowing that there is no escape. Soon they too will join in this miserable melody: this symphony of sickness.

But this big bad is nothing more than a smidgen of protein and a dash of genetic material: the rhinovirus!

This image is provided by Welcome Images. 

Yes, the culprit of this doom and gloom is none other than a virus, one of the tiniest and simplest microbes around. In fact, most scientists don’t even consider them alive. But be careful not to underestimate them!

Sometimes less is more. For viruses, to be pragmatic and efficient is to thrive. Rhinoviruses, for one, have only one gene in the form of single-stranded RNA. This single gene contains instructions for assembly of 11 different proteins: four for the body of the virus, and the remainder for use in replication.

But packing light has its downfalls, such as hoarding the hotel shampoo and “borrowing” that one item you forgot, but just can’t survive without from the front desk. And viruses are no different. In fact, they’re some of the finest moochers around (second only to us starving college students, of course).

To cause a cold, a rhinovirus first hitches a ride on a receptor on the cells in our throat and nose, before finagling its way inside. There, the virus sweet talks the cell into making copies of and making proteins from the virus RNA rather than the cell’s own DNA. The new viruses created ultimately burst free to attack other nearby cells.

Ironically enough, however, the actual symptoms and feelings of illness and fatigue that complement a cold come from our own immune system rather than the virus itself. As the immune system digs the trenches, calls for reinforcements, and settles in to fight it out with the virus, it also drastically saps our energy and inflames the linings of our throat and nose.

Viruses clearly subscribe to the “strength in numbers” mentality. We have identified more than 200 different types of cold-causing viruses, but rhinoviruses, just one of these varieties, accounts for roughly half of cold cases each year. Unfortunately, due to their vast numbers, we will never be able to build up immunity to all of these viruses. According to Medical News Today, adults should anticipate suffering through 2-3 colds each year.

And contrary to the timeless warnings against sauntering outdoors in Wintertime because “you’ll catch cold,” it is actually our mass migration indoors and into closer confines with others during winter months that gets colds on the rise.

So how do you keep the cold at bay in college – the perfect recipe for illness?

The cold virus is transmitted either via direct contact with a contagious person, by inhaling droplets in the air from coughing or sneezing, or by touching an infected surface. But how is it possible to never contact an infected surface on a campus of more than 40,000 students?!

This photo is provided by Ethan Gruber. 

And to be honest, it’s probably not possible. But it is possible to keep anything from an infected surface from contacting your nose and mouth and causing an infection. Keeping your hands away from your face and sanitizing them before eating is a key to staving off the cold.

And as much as it has already been said, the legitimacy of bolstering our immune systems by eating vitamins, specifically vitamin C (can’t forget your OJ) and getting plenty of sleep, cannot be overstated. But another pointer is to avoid the gym if you do come down with a cold. While it is imperative to stay healthy in order to be able to deal with illness, exercise can actually weaken the immune system and exhausts even more energy when we need it most.

And this seems unfeasible for us caffeine-driven college students, but keep the stress under control! Stress puts a damper on our immune system and viruses take advantage. If left unattended cold viruses can sometimes advance into bronchitis or pneumonia. Remember it is just as important to take care of yourself as it is to get the grade!

For information on when to cave and talk to a doctor see this article from Mayo Clinic.

Good luck staying healthy!