How do you kill a virus?
You wake up in the morning and instantly you know something’s wrong. You’re feverish, you ache all over, and you’re afraid you’re going to be sick to your stomach. You hope you’re not coming down with something!
After a few more grueling days of fighting it, you finally admit that it’s time to see the doctor – maybe he can give you a pill or something that will kill this virus.
The next day at your doctor’s office, you describe the overwhelming exhaustion you feel, the blinding headache you’ve had for days, and the aching pain all over your body. Flushing with embarrassment, you also tell him about the more… icky symptoms you’ve been experiencing, like the vomiting, cramps and diarrhea that have had you practically living in the bathroom between bouts of restless, feverish sleep.
“I’m desperate, Doc”, you say. “Is there a pill or an antibiotic or something I can take?”
To your dismay, he shakes his head and says:
“Unfortunately, an antibiotic won’t do anything to help you. We’ll take blood and urine samples and run a culture test to be sure, but it sounds to me like you have a viral infection, and unfortunately, antibiotics don’t work on viruses.”
This is news to you, so your doctor patiently explains to you exactly what a virus is, and how viral infections – like the one you have – are different from bacterial ones.
Viruses and bacteria are both microbes – tiny organisms that are too small to see with the naked eye. Viruses are much smaller than bacteria – the largest virus is smaller than the tiniest bacteria – and it takes a power microscope to be able to observe these tiny intruders.
Both bacteria and viruses spread through contact with infected people, animals, surfaces or food, and both can cause symptoms like yours – digestive upset, muscle and joint pain and respiratory distress. But the similarities end there.
Bacteria are single-celled creatures that can reproduce on their own and can survive in a huge variety of environments, living comfortably in extreme heat or cold, in radioactive waste, and even in the human body. The fossil record shows that bacteria have been thriving on earth for more than three-and-a-half billion years.
Most bacteria are harmless to us, and many are helpful. For example, certain strains of bacteria thrive in our digestive system where they help us break down food – no wonder probiotic yoghurt has been all the rage lately. Trillions of bacterial microorganisms live in our bodies, making themselves at home in our digestive system, on our skin and even in our eyes and nose!
In fact, according to Meghan Jardine, Associate Director of Diabetes Nutrition Education at Physicians Committee, we might be “only ten per cent human. Ninety per cent of our cells are nonhuman, microbial cells.” In recent years, scientists have put this number at closer to forty per cent human cells – but that’s still pretty crazy when you think about it!
Although less than one per cent of all bacteria are harmful to people, the ones that do cause diseases can do some serious damage. Bacteria give off toxic chemicals which can damage human tissue and make us sick.
Bubonic Plague: the deadliest bacterial infection in history
The most dramatic example of a bacterial infection is the bubonic plague in Europe in the thirteen hundreds. As the plague spread, people throughout Europe were coming down with fevers and chills, vomiting and diarrhoea, and aches and pains. They also had nasty black boils that oozed blood and pus – a gruesome symptom that earned this plague the name The Black Death.
We now know that the infection was caused by a bacteria called Yersinia pestis, but of course, people knew nothing about that in the fourteenth century. By the time the plague subsided, it had killed an estimated twenty million people – a third of the entire population of Europe at the time. Since precise numbers are hard to come by, the death toll could have been much higher – some experts estimate that up to sixty per cent of the population was wiped out by a tiny, single-celled bacteria.
Killing bacteria with Antibiotics
Thankfully, we can now treat bacterial infections with antibiotics, which kill the bacteria causing the infection or at least slow its growth. Antibiotics are a fairly recent discovery – the first antibiotic was used in nineteen thirty-six, and it wasn’t until the late eighteenth century that a German doctor named Robert Koch even discovered that bacteria caused diseases. In the year nineteen hundred, before the invention of antibiotics, nearly thirty per cent of all deaths worldwide could be blamed on bacterial infections that can be easily treated with antibiotics today.
Viruses are much more fragile than bacteria. The virus’s core of genetic material is protected only by a thin protein coating. A virus can’t survive without a host, and can only reproduce by attaching itself to a host cell and inserting its genetic material into it.
Unlike bacteria, nearly all viruses cause diseases in humans. Viruses are usually programmed to target specific cells before it gets to work either replicating themselves – making new viruses until the host cells burst and die – or turning normal, healthy cells into malignant ones.
Viruses are responsible for a lot of common diseases. Everything from the common cold and flu to painful conditions like chickenpox and shingles, to serious infectious diseases like hepatitis and herpes, are all caused by viruses
Spanish Flu: The deadliest pandemic in history
The nineteen-eighteen Spanish Flu was the deadliest pandemic in history, and it was all caused by a microscopic virus. By the time the outbreak ended in 1999, nearly one-third of the entire global population had been infected, and as many as one hundred million people had died – three per cent of the world’s population.
During the outbreak, the average life expectancy in America dropped by nearly twelve years in a single year, and in 1918 more U.S. soldiers died of the flu than in combat, which is shocking considering that America was in the middle of World War One at the time.
You thank your doctor for educating you and correcting your misconceptions, but there’s still something that doesn’t make sense to you.
“I don’t get it, Doc,” you say. “I got my flu shot this year, so how did I end up still getting sick?”
“That’s a great question, actually,” he replies.
Why do I get sick despite getting a yearly Flu Shot?
He goes on to explain why getting the flu shot doesn’t always guarantee that you won’t get sick.
The flu shot isn’t always effective in part because there is no one single virus that’s responsible for the flu, and because viruses are constantly mutating and changing. Vaccines are developed for the most common and most serious strains of the flu virus, but it’s impossible to predict which strains will hit in any given year, and it takes time to produce a vaccine after a new strain becomes problematic.
Even if you got the right flu shot for the right strain, you can still get sick if your body’s response to the virus isn’t fast enough or strong enough, which can happen to older people, those with suppressed immune systems, or anyone who’s had significant exposure to the virus.
Vaccines work by exposing your body to antigens, parts of an inactive version of the virus, training your immune system to release antibodies and quickly and aggressively attack the virus before it can spread.
“Wow,” you say. “I had no idea how cool vaccines are! Thanks for explaining them to me. But Doc, now that I have the virus, how do I kill it!”
How to kill a Virus
It turns out, there are lots of ways to kill a virus. Antiviral drugs exist to treat conditions like herpes and hepatitis. They work by interfering with an enzyme in the virus and preventing it from leaving one cell to infect another, but they don’t destroy the actual virus itself.
Killing viruses with lasers
One of the most exciting developments in virus-fighting technology is the use of lasers! Researchers at Arizona State University have shown that blasting a virus with purple laser light for one-hundred femtoseconds – a femtosecond is one-millionth of one billionth of a second – damages the virus’s outer shell, deactivating it.
“That’s great news! Bring on the drugs and lasers!” you say. You can’t wait to get some relief from the constant fatigue and nausea.
Again, your doctor shakes his head.
“Unfortunately, these treatments only work for specific viruses, and the common flu virus isn’t one of them. There’s not much we can do to kill the flu virus except let it run its course and give your immune system time to do its job. The symptoms you’re experiencing – the vomiting and diarrhoea, the fever and aches – are all your body’s way of trying to rid itself of an unwelcome intruder – in this case, the flu virus.”
Managing virus symptoms
Although there’s nothing you can take to kill the virus on the spot, there’s lots you can do to manage your symptoms. Your doctor recommends that you get plenty of rest and give your body time to do its job. He says you can take cough drops or honey for your sore throat, and use a humidifier to make breathing a little easier. He also suggests that you drink lots of fluids to combat the dehydration caused by all of your time in the bathroom, although he cautions you to avoid caffeine, as it can make dehydration worse.
He reassures you that you should be feeling better in a few days, but if not, you’re to come back in to see him so he can prescribe medication to treat any secondary infections or serious symptoms.
While you’re a little bit disappointed that there isn’t a magic pill to cure you – and that you won’t be seeing a laser today – you do feel reassured by your doctor’s words, and you’re ready to head home to get some rest. But, just as you turn to leave, a wave of anxiety comes over you.
“Hey Doc,” you say, hesitantly. “All this talk of vaccines and flu outbreaks has me a little bit freaked out. What’s to stop another flu pandemic from happening, like the Spanish Flu outbreak that you mentioned earlier?”
“Another great question!” he says.
How Viruses Spread
He explains that we know so much more about viruses and have so many more tools to fight them than we did back in nineteen-eighteen. Aside from vaccines and antiviral drugs, we now have technology that allows us to share information about viruses and track outbreaks in real-time.
We also have a much better understanding of how viruses spread, which means we know how to contain them. Viruses spread through contact with infected people, especially in situations where bodily fluids are exchanged, like coughing, sneezing, kissing and…ahem…sex.
You can also contract a virus through contaminated food and water, and many viruses can survive on hard surfaces for a few hours or even a few days. Animals can carry viruses, too – livestock, insects, birds, bats and even our pets can unwittingly spread viruses to humans.
Simple habits can help stop the spread of viruses. Wash your hands frequently and use hand sanitiser, especially after touching germy surfaces like doorknobs. Disinfect surfaces, avoid shaking hands, and try not to touch your face or rub your eyes. During outbreaks, medical officials may implement quarantine measures to limit the spread of a virus.
Even with all of these advances, a viral outbreak is still a major concern, especially since the world is more connected today than ever before. The precautions I just mentioned can help limit the spread of a virus, but stopping outbreaks before they start is a much more effective way to kill a virus.
Vaccines as the most effective weapon for stopping viruses
Vaccines are the very best weapon we have against viruses. Since Louis Pasteur debuted his rabies vaccine in eighteen eighty-five, we can thank vaccines for all but eradicating countless diseases that had previously caused untold suffering and devastation. Because of vaccines, formerly common diseases like polio, smallpox, typhoid and tuberculosis have become incredibly rare in most of the world throughout just a few generations.
One of the most important parts of the vaccination strategy is something called herd immunity. When a significant portion of a population is vaccinated, it makes it difficult for a virus to travel from person to person, limiting the spread of the virus.
Herd immunity is important for protecting vulnerable people who can’t be vaccinated, like very young children, older individuals and people with compromised immune systems. These groups also tend to be most a risk for complications from viral infections, so even if you’re not worried about protecting yourself from viruses, others are depending on you being vaccinated to protect them.
“Yes”, says your doctor as he walks you out. “Vaccines are certainly the most effective way to kill a virus.” See more