Asymptomatic transmission of COVID-19 very rare, WHO declares
Contrary to the World Health Organisation (WHO’s) advice on the control of the spread of coronavirus, an official of the global health body yesterday declared that it is rare for asymptomatic patients to transmit the disease.
The WHO, however, added that, “Much is still unknown about the COVID-19 pandemic.”
Its comments by one of its scientists that transmission of coronavirus from persons who never showed symptoms was “very rare,” drew criticisms from physicians and others experts on social media.
That admission sent shock waves throughout the world, much of which has been locked down for months for fear of spreading the virus by persons who show little or no signs of the virus.
Director General of the Nigeria Centre for Disease Control (NCDC), Dr. Chikwe Ihekweazu, had on his tweeter said, “About 80 per cent of COVID-19 cases show mild or no symptoms at all. These cases won’t be in isolation facilities under normal circumstances.
“Asymptomatic patients are primarily isolated to prevent transmission of the virus, especially to their loved ones”
An asymptomatic person is someone with COVID-19 who does not have symptoms and never develops symptoms. Both scientists clarified that it is not the same as someone who later develops symptoms, who would be classified as pre-symptomatic.
The first published study on how the first 32 patients with coronavirus in Nigeria were treated, showed that 75 per cent of them presented in moderately severe condition, while 16 per cent were asymptomatic. The most common presenting symptoms amounted to 59 per cent and dry cough constituted 44 per cent.
The study titled “Clinical presentation, case management and outcomes for the first 32 COVID-19 patients in Nigeria” was published in The Pan African Medical Journal.
Head of WHO’s emerging diseases and zoonosis unit, Dr. Maria Van Kerkhove, said, “Asymptomatic spread is a really complex question and much is still unknown. We don’t actually have that answer yet.”
Meanwhile, she explained that studies also have shown that about 16 per cent of the population may be asymptomatic, saying that some models developed by other scientists suggest about 40 per cent of global transmissions may be due to asymptomatic individuals.
Executive Director of WHO’s Emergencies Programme, Dr. Mike Ryan, said, “While asymptomatic spread of coronavirus does occur, the portion of individuals who transmit the virus remains a big open question. There is much to be answered on this. There is much still unknown,” he added.