A woman in her 50s, who hails from Vadaserikara village in Kerala’s Pathanamthitta district, was admitted in the District General Hospital on March 10 when she tested positive for SARS-CoV-2. She was a primary contact of a three-member family who had returned from Italy and tested positive on March 8.
While others who got the infection from the same family recovered and were discharged after two consecutive tests turned negative in two weeks, the woman continued to be under treatment at the hospital. Her test results continued to show positive for coronavirus. Finally, 46 days after being admitted, the woman was finally discharged on April 24.
Now, Pathanamthitta district has a similar case again. A 53-year-old man, who had returned from England in the United Kingdom, tested positive on March 25 and has been undergoing treatment since then. It has been 43 days and the man’s samples are still showing positive for the virus.
According to Dr Nandini CS, the District Surveillance Officer of Pathanamthitta, his RT-PCR or reverse transcription-polymerase chain reaction (PCR) test results have been showing positive, but the man is asymptomatic currently.
So why are some patients' samples returning positive even after their symptoms have subsided?
When the coronavirus infects an individual, it invades the host’s cells and begins to incorporate its genetic material into the cells. The genetic material found in this particular virus is RNA (ribonucleic acid), which is similar to DNA (deoxyribonucleic acid). When the host cell undergoes division, the viral genes are replicated too, thereby keeping the virus’ RNA active and circulating.
“Although a patient may not show any symptoms, there are fragments of coronavirus RNA in his body. The woman’s samples turned negative three times, but this man’s samples were single negatives, which is why we cannot discharge him yet,” said Dr Nandini. As per the discharge criteria, two consecutive samples should test negative before a person can be discharged.
The district officials said they are currently relying on international studies to gauge that such patients are still testing positive not because they are infected but because of the RNA fragments in the cell.
“The RT-PCR is a sensitive test. It is used to detect viral RNA. So it can pick up such fragments although the virus may not be active,” she elucidated.
Real time polymerase chain reaction, or RT-PCR is the standard test which is being used to diagnose COVID-19. In RT-PCR, the genetic material in the samples of an individual are amplified using certain techniques, resulting in several copies of an individual’s sample. This is then run through a test and a program can identify if there is any presence of the viral RNA in the sample. Even if the viral load is low, the test can detect it in this manner. As a result, individuals who are recovering and are not showing any symptoms of an active infection, who still have some viral particles in their cells, may still test positive for the virus.
“This means that he cannot spread the virus to others. But, in some cases, throat swabs show fragments that have not completely disappeared in the body. Otherwise, such patients are perfectly normal,” said Dr R Sandhya, Kollam District Surveillance Officer (DSO). Kollam, according to the DSO, currently has three such cases where there has been a delay in discharging individuals who have been testing positive though they are not showing symptoms.
This results in individuals showing different recovery times.
“Patients in the Italy cluster took a longer time to recover when compared to patients in Dubai clusters,” Dr Nandini notes.
Meanwhile, the Pathanamthitta district officials are waiting for three more test results of the patient from England. “If he is still showing positive, we will convene a medical board meeting to decide the next course of action,” said Dr Nandini.
He was initially given symptom-based treatment, antiviral drugs and Hydroxychloroquine (HCQ). Currently, he is being administered only multi-vitamin tablets to improve his immunity.
Giving emotional support
“These patients are anxious, and wonder why they are not testing negative yet,” explains Dr Sandhya.
For such patients, district officials are taking steps to ensure that these individuals have access to all emotional support facilities.
“Our psychologists gear up in the Personal Protective Equipment (PPE) and visit the English patient’s room to counsel him on a regular basis. He is constantly in touch with his family over the phone,” Pathanamthitta District Medical Officer (DMO) Dr AL Sheeja said. In Kollam, the patients are given their favourite food, books and can watch television.
(With inputs from Dr Nimeshika Jayachandran)