A few months ago, we discussed a question as common as the cold that inspired it: Why haven’t we cured viruses yet?

This was back when COVID-19 still didn’t have an official name, and if someone mentioned “social distancing” you’d think they were talking about an ‘80s punk rock band rather than a way of life. Obviously, things have changed… and we’re more interested in this topic than ever.

So today, we’re going to revisit the subject – and go one step further. We’ll talk about why it’s so difficult to find a cure for COVID-19, plus what it will take to find a vaccine. Let’s start with a summary of why we can’t cure viruses…

Why can’t we cure viruses?

Image source: MicrobiologyInfo.com

In our last post on this topic, we learned that we can’t cure viruses because they’re so simple. Unlike bacteria, which are complex and thus easy to target with medicine, viruses blend in much better – so we can’t use medicine to “seek and destroy” them without risking damage to healthy organisms.

To put it another way, destroying bacterial infections is like hunting for a needle in a haystack; you can just burn the hay. But destroying viruses is like hunting for a needle in a stack of needles. Since there are few unique characteristics, it’s impossible to safely design a drug that can attack JUST the virus.

That’s why we don’t try to cure the virus itself. Instead, we focus on managing symptoms and keeping your immune system strong so it can fight the virus itself.

In the case of COVID-19, the most dangerous symptoms involve fever and respiratory problems. If we can help alleviate those symptoms, their body will eventually eliminate the virus. That’s why much of the emergency care is focused on improving breathing and reducing fever – not attacking the virus itself.

While some medication can help your body fight symptoms and eliminate the infections caused by viruses, there are no direct virus cures.

This is where vaccines come into play. Since we can’t cure viruses like bacteria, our best bet is to prevent the illness in the first place – which is why we use vaccines.

What is a vaccine, and how do they work?

Image source: Health Synonyms

A vaccine is a biological preparation that, once injected, gives you immunity to a specific disease. The way they work is rather simple, though it may surprise you if you’re not already aware:

Each vaccine contains a veeeery small amount of the virus it’s protecting you against. Of course, the virus will be “inactive” – either dead or very weak – so you’re not at risk of actually catching the disease.

Once your body receives the vaccine, your immune system will start fighting the virus it contains. To do that, it creates antibodies – special cells that are designed to eliminate the invading virus.

Your body quickly wins this “battle” – you won’t notice a thing. But now that your immune system has experience fighting this specific virus, it’s prepared for the next time. Your immune system “remembers” all the viruses it’s seen – so if you end up catching the virus in the wild, it will immediately react by creating the correct antibodies to fight it off before it can cause illness.

This is how vaccines work – and they’re highly effective. According to the WHO, most vaccines are 85-95% effective in preventing the patient from the disease. (In the other cases, the body may have “forgotten” how to make the antibodies, or the vaccine didn’t contain enough of the virus in the first place.)

So, uh… when will we get a COVID-19 vaccine?!

Image source: WUR

You’ve heard the good news: even though we can’t cure viruses, vaccines can still protect us. However, the bad news (right now) is that vaccines take a long time to develop.

We’ve heard all sorts of projections about the eventual COVID-19 vaccine, but the fact is, only time will tell. When creating a vaccine, you have lots of options – which means you need lots of testing to find the best combination. We need to be 100% certain that a vaccine is completely safe and effective before we start using it, and that takes time.

That said, this vaccine will clearly be a team effort. The WHO claims there are already 60+ vaccines in the works for COVID-19, with some even close to entering human trials.

These vaccines are taking different approaches, too. Some use the classic approach we mentioned above – injecting a small amount of the inactivated virus to prepare your immune system directly. But others use a genetic molecule called mRNA rather than directly injecting SARS-CoV-2 into patients – their theory is that this will help cells mimic the proteins in the virus, allowing it to trigger a stronger immune response.

In addition, there’s another big reason we should take our time: antibody dependent enhancement (AED), a situation in which your antibodies aren’t strong enough to fight the virus – so instead, they end up leading the virus straight to healthy cells.

If a vaccine isn’t developed effectively, it can risk causing AED. This makes the person vaccinated to be MORE susceptible to the virus. That’s a big part of why we’re taking our time.

Conclusion: The vaccine may be far off, but it’s worth the wait!

So! To answer the million-dollar question: we simply don’t know when we’ll have a COVID-19 vaccine. Some estimates suggest we’ll have it by summer 2021, but that’s an optimistic projection. However, it’s likely that we’ll at least have it by 2022.

Err… does that mean we all have to stay home until 2022?! Almost certainly not. Although we’re all still learning, scientists believe there’s a good chance we’ll achieve “herd immunity” (in which the spread is limited because enough of the population is immune) much sooner than that. It’s not ideal, but neither was this pandemic… so while we can’t promise anything, we do feel optimistic about the future. We hope you do too!

That’s it for today. We hope you’re all staying safe and happy out there, and we’ll see you next week!