Case Study: How One Person With Good Immunity Beat The COVID-19 Virus Successfully

The deluge of information on the COVID-19 pandemic has only thus far stressed on the rising fatalities and signs of the disease. Not much attention has been given by the media to people with robust immunity. Since majority of the COVID-19 infections are mild to moderate, studying the immune response of the patients able to recover quickly is necessary to respond effectively. 

One such case is of a 47-year-old woman who landed in Melbourne 11 days before she developed symptons, from Wuhan, China, the epicenter of the outbreak. She did not visit the Huanan seafood market during her stay in China. Also, she did not encounter other positive cases. 

The woman’s recovery process, by way of her step-by-step immune response, was documented in a new study published by the medical journal Nature Medicine. Researchers at the Peter Doherty Institute for Infection and Immunity, a collaboration between University of Melbourne and the Royal Melbourne hospital, analyzed her blood samples four times during the period of 20 days, right from the onset of the disease till she recovered.  

The patient was admitted to the Royal Melbourne Hospital's A&E department four days after displaying mild or moderate symptoms of sore throat, chest pain, shortness of breath, fever, dry cough and tiredness. Henceforth, researchers followed her healing process closely through blood sample ananlysis. 

What The Study Found

The patient's immunity was considered good because she was not on medication for other preexisting conditions. Importantly, she was a nonsmoker. Doctors administered fluids intravenously and ensured she was never dehydrated. Surprisingly, she was not medicated with drugs at all. Antibiotics, steroids or antiviral agents were not used to aid her recovery, the paper said.    

In fact, the examination of her vital signs showed that her readings were slightly above the normal parameters. The results were the following: 

  • Body temperature: 38.5 °C 
  • Pulse rate: 120 beats per minute
  • Blood pressure: 40/80 mm Hg
  • Respiratory rate: 22 breaths per minute. 

“Three days after the patient was admitted, we saw large populations of several immune cells, which are often a tell-tale sign of recovery during seasonal influenza infection, so we predicted that the patient would recover in 3 days, which is what happened,” study co-author Dr. Oanh Nguyen explained. “We looked at the whole breadth of the immune response in this patient using the knowledge we have built over many years of looking at immune responses in patients hospitalized with influenza.”

GettyImages-1214527882 Doctors test hospital staff with flu-like symptoms for coronavirus (COVID-19) in set-up tents to triage possible COVID-19 patients outside before they enter the main Emergency department area at St. Barnabas hospital in the Bronx on March 24, 2020 in New York City. Misha Friedman/Getty Images

Blood samples were taken a week after the onset of symptoms, for three days consecutively, namely on days 7,8 and 9. During this time, the researchers noted a surplus of immunoglobulin G, a common antibody generated to fight viruses. On the same three days, antibody-secreting cells (ASCs) and specialized helper  T cells that activated CD4 T cells and CD8 T cells were found in the blood samples.

Simultaneously, an increase in immunoglobulin M, another antibody, was noted. This immune response indicated that the body galvanized the collective effort of the immune system to destroy COVID-19 virus invincibly. The patient left the hospital 11 days after experiencing the symptoms. As per the researchers, the immunoglobulins lasted in the system up to 20 days from the onset, though she stopped having symptoms after 13 days. 

The researchers in Australia were prepared to meet different biological sampling requirements, specifically among travelers who returned from an unpredictable infectious outbreak. Considering this is how the pandemic moved across the world, the Sentinel Travellers and Research Preparedness for Emerging Infectious Disease (SETREP-ID), led by Royal Melbourne Hospital Infectious Diseases Physician Dr. Irani Thevarajan benefited immensely from their pre-planning. 

“When COVID-19 emerged, we already had ethics and protocols in place so we could rapidly start looking at the virus and immune system in great detail. Already established at a number of Melbourne hospitals, we now plan to roll out SETREP-ID as a national study,” Thevarajan said.

“We showed that even though COVID-19 is caused by a new virus, in an otherwise healthy person, a robust immune response across different cell types was associated with clinical recovery, similar to what we see in influenza,” Prof. Katherine Kedzierska, study co-author, said. “This is an incredible step forward in understanding what drives recovery of COVID-19. People can use our methods to understand the immune responses in larger COVID-19 cohorts, and also understand what’s lacking in those who have fatal outcomes.”