W.H.O.: Data Suggests Omicron Causes 'Milder Disease than Delta'

Recent data out of South Africa suggests Omicron, a new variant of the Chinese coronavirus, “causes milder disease than Delta,” World Health Organization (W.H.O.) director-general Tedros Adhanom Ghebreyesus told reporters Wednesday.

“Emerging data from South Africa suggests increased risk of reinfection with Omicron,” Tedros said at a December 8 press briefing, adding “there is also some evidence that Omicron causes milder disease than Delta.”

The W.H.O. chief referred to the Delta variant of “Covid-19,” or the name of the disease caused by a type of coronavirus known as SARS-CoV-2. Delta was the latest and most dominant strain of “Covid-19,” or the Chinese coronavirus, to date until Omicron emerged in the southern African nation of Botswana in mid-November.

Delta emerged in India in December 2020 and has since become the most common SARS CoV-2 variant worldwide. The strain “is believed to be more than twice as contagious as previous variants,” Yale Medicine reported on November 19. Delta is capable of penetrating the immunity of people fully vaccinated against the Chinese coronavirus, among whom it has caused an increasing number of “breakthrough” infections.

“[D]ata also has shown the variant [Delta] to have increased transmissibility even among some vaccinated people,” Yale Medicine noted.

“[I]f a vaccinated person is infected with COVID-19 (in what’s called a ‘breakthrough’ case) and they have symptoms, they can transmit the virus to others,” the health news site noted, citing data from the U.S. Centers for Disease Control and Prevention (CDC).

Data has emerged in recent weeks out of southern Africa indicating Omicron may be more contagious than Delta.

The data suggests Omicron is “efficiently transmitting, and probably more efficiently transmitting even than the Delta variant,” Michael Ryan, the executive director of the W.H.O.’s Health Emergencies Programme, told reporters at Wednesday’s press briefing.

Despite Omicron’s seemingly high rate of transmissibility, the virus strain appears to correlate with a low rate of hospitalization in southern Africa so far.

“Data which looked at hospitalizations across South Africa between 14 November and 4 December found that ICU occupancy was only 6.3 percent – which is very low compared with the same period when the country was facing the peak linked to the Delta variant in July,” the W.H.O. reported on December 9.

“Data from the same two-week period from one of the health districts most impacted by Omicron found that out of more than 1,200 admissions, 98 were receiving supplemental oxygen and only four were on ventilation,” the U.N. health agency revealed.

Dr. Anthony Fauci, the director of the U.S. National Institute of Allergies and Infectious Diseases (N.I.A.I.D.), said Tuesday preliminary studies of Omicron suggest the variant is likely to cause mild illness. Speaking to Agence France-Press (AFP) on December 7, Fauci said the severity of illness caused by Omicron “almost certainly is not more severe than Delta.”

“There is some suggestion that it might even be less severe [than Delta], because when you look at some of the cohorts that are being followed in South Africa, the ratio between the number of infections and the number of hospitalizations seems to be less than with Delta,” he acknowledged.

“Covid patients infected by the Omicron variant, whether vaccinated or not, usually experience mild symptoms, though in the unvaccinated, they are more intense and last longer,” South African Dr. Angelique Coetzee told the Print, an Indian news site, on December 9.

“[M]ost of the [Omicron] cases are mild, no need for hospitalization. No oxygen needed for majority patients,” she revealed.

Dr. Angelique Coetzee was the first physician to detect Omicron while treating one of her patients in November in South Africa. Coetzee serves as the Chairwoman of the South African Medical Association (SAMA).