'COVID-19 immunity may disappear within months'

A municipal worker pushes a cart passing by graves in Ciudad Nezahualcoyotl, Mexico. Pic/AFP

Patients who recover from novel Coronavirus infections may lose their immunity to re-infection within months, according to research released on Monday. A team led by researchers from King's College London examined the levels of antibodies in over 90 confirmed virus patients and how they changed over time.

Blood tests showed even individuals with only mild COVID-19 symptoms mounted some immune response to the virus. Of the study group, 60 percent showed a "potent" viral response in the first few weeks after infection.

No antibodies after 90 days
However, after three months only 16.7 percent had maintained high levels of COVID-19-neutralising antibodies, and after 90 days several patients had no detectable antibodies in their bloodstream.

As long as someone has enough antibodies, they will be able to snub out new infections, giving them immunity. But Monday's research suggests immunity cannot be taken for granted and may not last more than a few months. Experts said the findings may change how governments plan for the next phase of the pandemic, including how they fund and organise vaccine research and development. James Gill, an honorary Clinical Lecturer at Warwick Medical School, said, "Even those with a positive antibody test should continue to use caution, social distancing and appropriate mask use."

Meanwhile, the World Health Organisation on Sunday reported a fresh record with 2,30,370 new cases worldwide over a 24-hour period. Florida shattered the national record for the largest single-day increase in cases in any state with 15,299 new ones, on Sunday.

Mexico, with 35,006 COVID-19 deaths, became the country with the fourth highest total toll, followed by the United States, Brazil and Britain. Sunday's rise to confirmed deaths moved Mexico, a country with 130 million inhabitants, past Italy.

South Africa, Hong Kong tighten curbs

The Hong Kong government is contemplating to tighten physical distancing measures to contain the third wave of coronavirus outbreak after new cases of COVID-19 were reported on Monday. About 30 per cent of new cases in city were proving to be untraceable. On Sunday, out of 38 cases, 30 were locally transmitted and in 13 of those cases, source of infection was unknown.

Some people believe it is time to return to several restrictions that were placed in March. In South Africa, President Cyril Ramaphosa said they will immediately return to a ban on the sale of alcohol to reduce the volume of trauma patients so that hospitals have more beds to treat COVID-19 patients. Confronted by surging hospitalisations due to COVID-19, South Africa is also reinstating a night curfew to reduce traffic accidents and made it mandatory for all residents to wear face masks in public. South Africa, ranked as the 9th most-affected country, has reported 2,64,184, cases of COVID-19 including 3,971 deaths.