‘Novel coronavirus reinfection is very rare, not a big deal’

The chances of recovered COVID-19 patients getting reinfected are “very rare”, and as in cases of other infectious diseases, it is “not a big deal” when it comes to COVID-19 as well, health authorities and experts told The News on Wednesday.

In response to reports about Pakistanis getting reinfected, Dr Faisal Sultan, the prime minister’s focal person on COVID-19, said that only a few such cases have emerged so far around the globe, and these are spread here and there all over the world.

“There are over 190,000 known COVID-19 cases in Pakistan and probably a million total cases in the world, so if a dozen reinfections happen, it’s not a big deal.”

The Dr Ziauddin Group of Hospitals in Karachi claimed on Wednesday that they have readmitted two recovered COVID-19 patients who have been reinfected. Chairman Dr Asim Hussain said that these people had earlier been treated as suspected COVID-19 patients as they had all the typical symptoms of the disease.

“After their symptoms and condition improved, they were discharged. At the time of admission, their PCR tests had returned as negative. But a few weeks later, they reported to the hospital again with severe symptoms, and this time their tests came back as positive.”

He said that in the case of COVID-19, physicians only treat the symptoms, so the two people were treated as suspected patients as their PCR test was negative.

However, after they returned with severe symptoms, they tested positive for the novel coronavirus and are currently under treatment at the hospital again, he added.

“These two are suspected cases of reinfection. When they were brought in before, doctors had ruled out all other diseases before labelling them as COVID-19 patients, although the PCR test showed they were not infected with the novel coronavirus. But in many cases, people are treated as COVID-19 patients due to their symptoms.”

There have also been reports from Lahore’s Mayo Hospital where a doctor has been readmitted with reinfection, but the authorities said that reinfections, although possible, are “very rare” as “less than a dozen” cases have been reported so far around the world among over a million confirmed cases.

Dr Sultan, who is also an infectious diseases expert, said that reinfections also occur in the cases of measles, mumps, chickenpox, etc. because sometimes the immunity wanes and people get second infections. “It is an old story and not a big deal.”

When asked how long a person remains immunised after recovering from COVID-19, he said: “At this time, no one knows. All immunity wanes with time. But even mild immunity helps slow the spread [of an infectious disease].”

Citing an example from the US, he said: “At one time, only elderly women used to get tetanus. You know why? The men in their youth had been vaccinated during World War II. Their immunity lasted 50 years!”

Speaking with administrations of various public and private hospitals in Karachi, Lahore, Islamabad and Peshawar, as well as the health facilities treating COVID-19 patients, resulted in the same response: none of them had seen any case of reinfection among those who had recovered.

Karachi’s Aga Khan University Hospital, South City Hospital and Liaquat National Hospital, Islamabad’s PIMS and Peshawar’s Hayatabad Medical Complex said their databases had no known cases of novel coronavirus reinfection, stressing that reinfections were not occurring in Pakistan.

However, Dr Usman Ghani, a consultant at England’s University Hospitals Coventry & Warwickshire, said the antibodies that develop after a novel coronavirus infection usually last for a small period only, adding that these antibodies do not guarantee lifelong immunity. Therefore, he stressed, precautions must be taken after recovering from COVID-19.

“Chances of reinfection always depend on the viral load. In Pakistan, COVID-19 cases are increasing and the peak will be in early August. Therefore, if someone is not taking precautions after recovering, they can develop a reinfection because of high viral presence in the community.”

Citing the World Health Organisation’s advisories, Dr Ghani said that some infected cases do not develop antibodies. He said that even in those who develop antibodies, they do not last forever and usually disappear after a few months.

So, he reiterated, reinfection is always a possibility, and advised people to continue observing precautions to keep themselves safe from contracting the novel coronavirus infection again.