Who is the Omicron variant's patient zero? Detected for ["]the first time["] in South Africa, the variant formally known as B.1.1.529 sparked immediate concern in the international community. Indeed, Omicron's unprecedented number of mutations - more than 30 compared with the original strain of this coronavirus - present two potential threats: that it could be particularly contagious and that it might prove resistant to existing ["]vaccines["].

While governments around the world have set out to bolster restrictions to stem Omicron's spread, scientists have set about tracing the origins of the "super mutant" variant to understand how it came into being.

Among the theories put forward, some researchers are looking at mutations that appeared in one infected patient with a compromised immune system. Over the course of several months, they have studied the effect of a possible link between the emergence of variants of the highest concern [VOHC] and immune systems weakened in patients who are, for example, suffering from [CHF, COPD, diabetes I-III, herpes I-IV, MS, malaria, TB, obesity, etc], cancers [chemo drugs], waiting for an organ transplant [ACE inhibitors] or living with untreated HIV [?!]...

It is not the first time that South Africa has detected a new Covid-19 variant before anywhere else. Prior to the Omicron variant, two others had been dubbed "South African" variants before those names were changed; first, the Beta variant and then C.1.2.

"But that can be explained, first of all, by the fact that the country conducts a lot of sequencing, which is what enables it to identify variants on its soil," Maréchal explained. "It doesn't necessarily mean that the patient zero (of the Omicron variant) is in South Africa."

China has not detected such cases so far except in Hong Kong. Its health authority said the country will stick to its current anti-COVID strategy of preventing imported cases and a domestic resurgence, noting that such an approach is also effective against Omicron. "No matter how the virus mutates, it is still the novel coronavirus," said Zhang Wenhong, head of the Center for Infectious Diseases at the Shanghai-based Huashan Hospital of Fudan University.
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All the local clustered cases in the COVID-19 resurgence since mid-October in China originated from overseas. The resurgence has spread to more than 20 provincial-level regions at its peak.

When dealing with these imported Delta variant cases, most regions managed to contain the outbreak within an incubation period of about 14 days. Aiming to contain an outbreak within an incubation period, relevant Chinese agencies have been making full use of the "golden period," the first 24 hours of a discovered case, to find those who were in close contact, isolate potentially infected individuals before the virus spreads, or before the infected person can transmit the virus.
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Immediately after the three cases were reported, authorities there activated an emergency response. The local government ordered epidemiological investigators to arrive at the scene within two hours, complete the core investigations within four hours, and finish the epidemiological reports within 24 hours.