
In the world's first "human challenge," researchers at Imperial College London purposefully infected volunteers with COVID to see the effects, and reported them in a new study. "The collaborative study is the first in the world to perform detailed monitoring over the full course of COVID-19, from the moment a person first encounters SARS-CoV-2, throughout the infection to the point at which the virus is apparently eliminated," says Imperial College London. In it, researchers discovered how soon COVID symptoms start after exposure, and found where the infection appears. "The findings, published on a pre-print server and which have not yet been peer-reviewed, detail the outcomes in 36 healthy, young participants with no immunity to the virus." Read on to find out everything—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.
Symptoms Develop "Very Fast"—As Soon as Two Days After Exposure

"Among several key clinical insights, researchers found that symptoms start to develop very fast, on average about two days after contact with the virus. The infection first appears in the throat; infectious virus peaks about five days into infection and, at that stage, is significantly more abundant in the nose than the throat," says the College.
This is Where the Infection Appears

"The infection first appears in the throat; infectious virus peaks about five days into infection, which is also when the most significant symptoms are usually noticed, the researchers said. At that stage, the virus is significantly more abundant in the nose than the throat," reports Reuters.
Here are the Common COVID Symptoms

Dr. Eric Cioe-Peña MD, director of Global Health and Emergency Department physician at Staten Island University Hospital, says: "The first signs tend to be congestion and other symptoms of an upper respiratory infection (sore throat, etc). You should test after an exposure, or any COVID-compatible symptoms. Testing before you see vulnerable family members even if asymptomatic is still inadvisable."
The Centers for Disease Control and Prevention states, "People with COVID-19 have had a wide range of symptoms reported – ranging from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus. Anyone can have mild to severe symptoms. People with these symptoms may have COVID-19:
- Fever or chills
- Cough
- Shortness of breath or difficulty breathing
- Fatigue
- Muscle or body aches
- Headache
- New loss of taste or smell
- Sore throat
- Congestion or runny nose
- Nausea or vomiting
- Diarrhea
This list does not include all possible symptoms."
Unvaccinated People are 97 Times More Likely to Die

CDC Chief Rochelle Walensky this week showed data from 25 "US jurisdictions that report cases and deaths linked to vaccination status…Vaccination and booster doses substantially decrease the risk of death from COVID-19. Looking at the data from the weekend, December 4th, the number of average weekly deaths for those who were unvaccinated was 9.7 per hundred thousand people, but only 0.7 per hundred thousand people for those who were vaccinated. This means the risk of dying from COVID-19 was 14 times higher for people who were unvaccinated compared to those who received only a primary series. For those who were boosted, the average of weekly deaths was 0.1 per 100,000 people—meaning that unvaccinated individuals were 97 times more likely to die compared to those who were boosted."
How to Stay Safe Out There

Follow the public health fundamentals and help end this pandemic, no matter where you live—get vaccinated or boosted ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.