Recently, a video went viral. In the viral video clip epidemiologist and WHO technical lead on the coronavirus pandemic Maria Van Kerkhove was heard saying, “From the data we have, it seems to be rare that an asymptomatic person actually transmits onward to a second individual.”
Big Story: Unbelievable! Asymptomatic patients need no isolation … A complete U turn by WHO. After destroying the economy of the world now a complete U turn!! pic.twitter.com/HR0ioVgIqL
— Harsh Sanghavi (@sanghaviharsh) June 13, 2020
Van Kerkhove started by noting that in many countries, when COVID-19 cases have been contact traced, many of the seemingly asymptomatic cases were not completely without symptoms, but rather, had very mild symptoms.
“They may not have developed fever yet, they may not have had a significant cough, or they may not have shortness of breath,” she said, acknowledging that there were some people who were truly asymptomatic as well.
The remark caused an uproar as it contradicts many public health experts who have been talking about the asymptomatic spread of coronavirus.
The following day, the WHO clarified that it still does not have the answer to the intensity of spread caused by asymptomatic patients.
According to Dr. Oyuka Byambasuren, a researcher at Bond University’s Institute for Evidence-Based Healthcare in Australia who co-authored a systematic review and meta-analysis addressing asymptomatic transmission, WHO was correct to state that asymptomatic transmission is low, but that the term “very rare” was “probably inappropriate.”
Dr. Isaac Bogoch, an infectious disease specialist at the University of Toronto, put this differently. He said: “there’s “pretty good data” showing that pre-symptomatic people are responsible for some transmission of COVID-19. But there’s less information about people who stay symptom-free”.
Dr Anthony Fauci, the top infectious diseases expert in the US, also said the WHO’s statement on asymptomatic spread “was not correct”.
Symptomatic, Asymptomatic, Presymptomatic Symptoms Of Covid
Asymptomatic means a person has been infected by the virus, but does not feel sick or develop any symptoms.
Pre-symptomatic, which means a person does not show the symptoms in the early stages of the illness but develops them later on.
According to the World Health Organization (WHO), the most common symptoms of COVID-19 are fever, fatigue and a dry cough. Some patients may experience aches and pains, sore throat, diarrhoea, or a loss of smell or taste.
For those who are not asymptomatic, the time between infection and the onset of symptoms can range from one to 14 days. Most infected people show symptoms within five to six days.
Most Common Symptoms
- Fever
- Fatigue
- Dry cough
Less common symptoms
- Aches and pains
- Runny nose
- Sore throat
Are asymptomatic COVID-19 carriers less contagious?
This remains unclear and more research is required.
Based on current evidence, WHO says asymptomatically infected individuals are less likely to transmit the virus than those who develop symptoms.
Evidence shows that 25% to 45% of infected people likely don’t have symptoms, Fauci told ABC’s “Good Morning America” on Wednesday.
“And we know from epidemiological studies they can transmit to someone who is uninfected even when they’re without symptoms,” said Fauci, the director of the National Institute of Allergy and Infectious Diseases.
Studies suggest pre-symptomatic spread is more common than asymptomatic spread.
“Detailed contact tracing from Taiwan as well as the first European transmission chain in Germany suggested that true asymptomatics rarely transmit,” said Babak Javid, a principal investigator at Tsinghua University School of Medicine in Beijing and an infectious disease consultant at Cambridge University Hospitals.
Then, why everybody is talking about Asymptomatic transmission
- The virus is primarily spread via respiratory droplets when someone coughs or sneezes or if they touch a contaminated surface, scientists say.
- Asymptomatic transmission is particularly worrisome for public health officials, leading many to institute severe lockdowns and policies requiring masks in public. That’s because those patients never develop symptoms and, in many cases, don’t even know they are infected.
