12-15-2021, 12:01 AM
Quote:High levels of previous exposure to three previous waves of Covid infection in South Africa may explain the relatively low levels of hospitalisation and severe disease in the current outbreak of the Omicron variant, rather than the variant itself being less virulent. The suggestion was made by vaccine expert Shabir Mahdi of the University of the Witwatersrand, who has led vaccine trials in the country, and warned that South Africa’s experience of Omicron might not be a reliable indicator for how the Omicron outbreak unfolds in other countries.Coronavirus live: Omicron poses real threat, says Moderna chief; Pfizer says Covid pill near 90% effective | World news | The Guardian
In a lengthy interview with the Global Health Crisis Coordination Center, Mahdi cited a recently completed seropositivity survey – the percentage of population who have already been infected – in Gauteng province, which has been at the centre of the Omicron outbreak, that suggested some 72% had experienced a previous infection of coronavirus.
Quote:Two doses of Pfizer/BioNTech’s Covid vaccine appear to have given 70% protection against hospitalisation in South Africa in recent weeks, according to a major real-world study on the potential impact of Omicron. The study released by South Africa’s largest private health insurance administrator, Discovery Health, which co-led the study with the South African Medical Research Council. It was based on more than 211,000 positive Covid test results from 15 November to 7 December, around 78,000 of which were attributed to Omicron. Two doses of the vaccine offered 93% protection against earlier variants, according to Pfizer and BioNTech. It also found two Pfizer doses provide 33% protection against infection.Coronavirus live: Omicron poses real threat, says Moderna chief; Pfizer says Covid pill near 90% effective | World news | The Guardian