Coronavirus reinfection: Myth or reality?

The world has already been hit rock-bottom due to the novel coronavirus. Now the concern of its reinfection has spread dark clouds over the already-gloomy situation.

Reinfection could complicate the process of making a working vaccine or achieving herd immunity. We are only months into this virus and do not know exactly how this virus behaves yet.

Around the world, there have been several reports about people being reinfected by the virus after testing negative. 

Earlier in June, Md Shihab Uddin, a Bangladeshi physician from Barishal, tested positive after he had recovered from Covid-19 in April. There were several other rumors across the country saying more people were reinfected with the virus, but nothing was confirmed.

According to The New York Times, some people in China, Japan and South Korea tested positive twice. South Korea' Disease Control and Prevention investigated those 285 cases and found that several of the second positives came two months after the first, and in one case 82 days later. 

The US has seen quite a number of people being reinfected. Two separate Las Vegas boxers tested positive after recovering from the virus. According to MIC, a woman from Colorado named Michelle Hart swept the headlines as she tested positive for the second time in June. Within a month, a Google search for that story, "Colorado woman tests positive for Covid-19 twice," produced more than three million results. 

The New York Times reported a doctor saying a second round of illness was a reality for some people, and was much more severe.

These stories and people's reaction to the idea of being infected twice are alarming.  

However, experts are still confused about whether reinfection is normal or not. While some experts claim that the idea of testing positive twice is a myth, and there is no evidence of widespread vulnerability to reinfection, other experts have claimed it to be real and an alarming possibility. 

These cases are all anecdotal and they are, of course, alarming. It might seem real as everyone is thinking and talking about being reinfected when it's not scientifically proven yet. It is still very unlikely that the same person will be infected by the virus twice. 

Marc Lipsitch, an epidemiologist at the Harvard T.H. Chan School of Public Health, told the Times – "I haven't heard of a case where it's been truly unambiguously demonstrated."

Angela Rasmussen, a virologist at Columbia University in New York also told the Times that there has been no virological evidence that reinfection was happening. 

It is true that the same viruses can strike a person twice, but not in this short a period of time – according to some experts. Reports of reinfection may be cases of drawn-out course of a previous infection that had been lurking somewhere in their body. Or it might be some other virus with similar symptoms. 

It can take from weeks to months, depending on one's antibodies, to properly go away. 

Then again, antibodies are not the only form of protection from the virus. Our immune system is an army of connected cells which protects us all from all forms of internal and external dangers. The Times' experts explain that our immune system initiates a defense from cells as soon as it is attacked by any virus. It helps kill the virus and produce any help that might be required for the coming fight.  

These defense cells are commonly referred to as T cells and B cells. Antibodies are later produced after the T cells do their thing, though less is known about how long these T cells persist.

Some experts also claimed that either of the positive or negative results might have been false in some cases. That can be true in our country given the accuracy issue with some tests recently. 

According to The New York Times, most people who have been exposed to the virus make antibodies that fight and destroy the virus. The severe the symptoms, the stronger the response. Few recent studies suggest that antibody levels plummet and that has fueled the worries about reinfection.
  
According to USA Today, King's College researchers have found that antibodies peaked up to three weeks after battling with symptoms before declining.

A study in MedRxiv, on July 17, suggests that antibody level goes up when attacked by the virus, fights and destroys it and then declines before being stabilised. 

Dr. Michael Mina, assistant professor of Epidemiology at the Harvard T.H. Chan School of Public Health,  told The New York Times, "This is a famous dynamic of how antibodies develop after infection: They go very, very high, and then they come back down."

However, the World Health Organization (WHO) stated in April that, "There is currently no evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection."

Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City, told USA Today that the possibility of reinfection is very possible and certainly real.  

USA Today reported him saying a number of patients who suffer only mild infections get better within a few days and test negative before experiencing the recurrence of symptoms again. Glatter mentions that the intensity can be worse the second time. 

"We are months away from knowing for certain if reinfections are possible or a significant issue," Dr. Daniel Griffin told USA Today. 

"Longitudinal evaluation and decline of antibody responses in SARS-CoV-2 infection," according to another study in MedRxiv, "supports the possibility that Covid-19 could reinfect people repeatedly." 

Melissa Nolan, an infectious disease expert and professor at the University of South Carolina, said, as USA Today, reported, "Until we have a vaccine that is widely available, societies will not naturally develop their own herd immunity. These new findings suggest that persons might be reinfected."

So many people after recovering from an initial illness, have been reinfected – by almost every virus. This includes chicken pox – for which antibodies are supposed last a lifetime – plus Ebola and HIV/AIDS which all saw similar kinds of reinfection after people initially recovered from the virus. 

Among more than 15 million people who have been infected by the novel coronavirus, a small number of reinfections should not be alarming – yet. However, the question remains as to whether this is a rare situation.