The Dose of COVID-19 Determines the Level of Sickness

The Dose of COVID-19 Determines the Level of Sickness

Ayden Nguyen, Writer

During the early Renaissance, a Swiss philosopher stated, “The dose makes the poison.” What this quote is trying to imply is that too much of any substance can be unhealthy if not toxic. If you apply the same notion to COVID-19, you can infer that the more of the virus a person gets, the more sick a person will be.


The level of sickness is determined by the dose of the virus doesn’t just apply to COVID-19, but to other viruses including the Influenza virus, poxviruses, etc. Erin Bromage, professor at the University of Massachusetts, further explains this by saying, “If you hit an animal with a low enough dose, they’ll be able to fend that off without developing any disease at all. If you get a magic number of an infectious dose, an infection will establish and that animal will then succumb to the disease from that particular pathogen. But if you hit them with more than the infectious dose, in most situations a high dose of pathogens — like a high dose of a virus, for example– leads to more severe outcomes. So, dose becomes really important.” However, there is not a specific number of particles that you need to contract to get the virus. If you take in lots of particles, the chances that you will get the virus are higher.


If you have been exposed to someone with COVID-19 for a short period of time, you would take in less particles than if you were exposed to that same person for a longer period of time. This is why time is important. “Some people are speculating about it: Is this why, for example, bus drivers or people working in emergency rooms are more likely to have more adverse outcomes? Because they’re exposed to higher doses, or because they’re in an environment where they get exposed to it over an extended period and get a larger swath of it into them?” asked Bromage. The United States Centers for Disease Control and Prevention(CDC) altered the definition of “close contact,” to say multiple encounters to an infected person that add up to 15 or more minutes.


Although the virus plays a big role in whether or not a person gets sick, it also depends on the person’s health condition. “Each person has a different amount of virus that they need,” said Bromage, “Somebody that is immunosuppressed, or somebody that is stressed, for example, may need less of a challenge in order to get the same outcomes as somebody that is in a healthy condition.” If you add it all up, you can reason that the chance of infection depends on the host’s healthiness and personal behaviors. For example, someone who smokes, has an unhealthy diet, or lacks physical activity or sleep are more likely to contract the virus. This was the reason why in the beginning of the pandemic, many erderly died in nursing homes. The elderly were not only compromised, but they were in an environment where they were in close proximity to one another for an extended period of time.


Dr. Monica Gandhi, professor at the University of California, says “There is an interesting two-sides-of-the-coin dance coming out between viral [dose] — what goes in — and viral load — what comes out.” The amount of virus an infected person has is the person’s viral load. The sicker the patient, the higher viral load. However, there is a way scientists can use virus dosing to their benefit. If you give patients a really small dose of a virus, they may not get sick but their body will still produce antibodies against the virus. Essentially, virus dosing could work like a vaccine. Gandhi and Dr. George Rutherford wrote an article saying that if you wear a mask, you would contract less virus particles if you come into contact with an infected person. These particles may not infect you but your body will still make antibodies proving that if you wear a mask, your risk for COVID-19 would be much lower than if you didn’t wear a mask. “We’re going to give them a teeny bit of virus and they’re going to get just a teeny bit sick and then they’d develop an immune response — and it totally worked,” Gandhi said.


Since people cannot control how much viral load they get, Gandhi and other health officials continue to repeat what to do to stay safe. Social distance(stay 6 feet apart), choose places with more space if you are traveling, practice washing your hands and keeping your hygiene, and finally wear a mask.


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