Facts about Omicron and how to stay safe from it

Health Cabinet Secretary Mutahi Kagwe on Wednesday announced that Kenya had detected three cases of the Omicron variant of Covid-19.

Omicron, brought to the attention of the world by South African scientists after sequencing their coronavirus samples, has now spread in about 77 countries.

How was the variant named?

It becomes the fifth variant of concern to be officially recognised and named by the World Health Organisation. The WHO designated the variant B.1.1.529.

The variant was named after the 15th letter of the Greek alphabet, a consensus that the WHO came up with after deciding to skip two letters next in line after the Delta variant - Nu and Xi.

The letter Nu was skipped because its pronunciation is akin to new, and Xi was not an option because it is spelled just like a Chinese name and could be offensive to the Chinese people, explained Prof Walter Jaoko, microbiologist and specialist in tropical medicine, in a webinar with science journalists.

How fast is the variant spreading?

In a press briefing, WHO Director-General Tedros Ghebreyesus acknowledged that Omicron is spreading at a rate not seen with any previous variant.

Preliminary data from South African scientists shows that it spreads twice as fast as the Delta variant. They also discovered that most people who had the variant had been previously infected with Covid-19.

“Population-level evidence suggests that the Omicron variant is associated with substantial ability to evade immunity from prior infection. In contrast, there is no population-wide epidemiological evidence of immune escape associated with the Beta or Delta variants. This finding has important implications for public health planning,” said a South African study that is yet to be peer-reviewed.

What are studies saying about the variant?

Omicron is still fairly new and most studies around it are in pre-print version (yet to be peer-reviewed for publication in a scientific journal).

On Wednesday, a team of researchers presented their findings to the WHO and the latter acknowledged that while studies are coming in droves, and that is important, thorough reviews must be conducted.

The WHO indicated that Omicron is likely to escape vaccines because it has heavily mutated compared with previous variants.

A mutation happens when a virus changes its original genetic composition. In the case of Omicron, Prof Tulio de Oliveira, the director of the Centre for Epidemic Response and Innovation in South Africa, told the BBC that there was an "unusual constellation of mutations" and that it was "very different" from other variants.

He added that there could be about 50 mutations from Omicron and more than 30 on its spike protein, which makes its way to the body cells to cause an infection.

“The virus, and even the Omicron variant, is continuing to evolve,” said a report from the WHO.

Can vaccines work against the variant and what role does booster shots play?

The WHO said that available vaccines may be less effective against Omicron and a booster shot is likely to offer better results, but still, more investigation is needed.

“The vaccine effectiveness will be reduced against symptomatic disease – this is being borne out. This also suggests that vaccines will be less effective against transmission, and has implications for public health and social measures,” said the WHO report.

“Boosters may provide a short term benefit but possible short duration of effect, continuing virus evolution suggest they may not have a major effect in the course of the pandemic. We should consider further accelerating the development of new vaccines to cover Omicron, even if we are not sure we will need them.”

Different researchers whose work is also pending publication have established that existing vaccines may not fully protect against Omicron.

A report from the UK Health Security Agency indicated that about five studies, all pre-print, showed that there was about a 20 to 40-fold reduction in protection from the Pfizer-BioNtech vaccine for Omicron compared with a 10-fold drop for Delta.

“These early estimates suggest that vaccine effectiveness against symptomatic disease with the Omicron variant is significantly lower than compared to the Delta variant. Nevertheless, moderate to high vaccine effectiveness of 70 to 75 per cent is seen in the early period after a booster dose,” the report explained.

A disclaimer for UK early studies, just like the WHO caveat, is that the samples were taken in the early stages after Omicron was reported.

Is the variant worrying?

The WHO also said that Omicron is milder and leads to fewer hospitalisations. Those admitted with the variant do not stay long in hospital.

“Even if disease is milder, rapid onslaught of the virus could overwhelm health care systems. Projected transmission rates, if borne out, do not give us much time for interventions.”

Its mild nature presents symptoms associated with the previous strains of the coronavirus but no specific symptoms have been published even in the yet-to-be-peer-reviewed studies.

What symptoms does it present with?

The WHO is coordinating with researchers around the world to better understand Omicron. Studies underway or that will start shortly include assessments of transmissibility, the severity of infection (including symptoms), the performance of vaccines and diagnostic tests, and the effectiveness of treatments. 

Most of its symptoms, such as headache, runny nose, sneezing, sore throat and loss of smell, are all observatory reports from different hospitals that have screened for Omicron.

Recommended actions for people

Some of the most effective steps individuals can take to reduce the spread of Covid-19 are keeping a physical distance of at least one metre from others and wearing a well-fitting face mask.

The others are opening windows to improve ventilation; avoiding poorly ventilated or crowded spaces; keeping hands clean; coughing or sneezing into a bent elbow or tissue; and getting vaccinated when it is their turn.

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Additional reporting by Elizabeth Merab