It's sometimes hard to remember quite how much <a href="https://www.thenationalnews.com/tags/covid" target="_blank">Covid-19</a> has expanded our epidemiological vocabulary during the past year and a half. Now, there's a new word that is worrying experts, governments and ordinary people the world over: <a href="https://www.thenationalnews.com/travel/covid-19-travel/2021/11/27/how-omicron-is-affecting-flights-emirates-and-klm-issue-restrictions-on-african-countries/" target="_blank">Omicron</a>, or, as it was known at first, <a href="https://www.thenationalnews.com/world/europe/2021/11/26/who-summit-over-b11529-nu-variant-after-south-africas-cases-spike-by-93/" target="_blank">the "Nu" variant</a>. It refers to a new strain of Covid-19 that was recently identified in South Africa. It is spreading, with <a href="https://www.thenationalnews.com/coronavirus/2021/11/25/six-african-countries-added-to-red-list-as-uk-sounds-alarm-over-new-coronavirus-variant/" target="_blank">cases reported throughout southern Africa</a> and as far as Belgium and Hong Kong. It is too early to know quite how dangerous it is. And while worrying, the situation seems relatively manageable for now although the world must remain alert. The chair of the South African Medical Association, Angelique Coetzee, has said only "very mild cases" have been spotted in her country. In general, new virus strains rarely pose a significantly greater danger in terms of individual illness. The most serious potential threat is on a larger, global scale. <a href="https://www.thenationalnews.com/coronavirus/2021/11/26/whats-known-about-new-b11529-nu-covid-variant/" target="_blank">Omicron</a> appears to be the most radical Covid-19 mutation to date. This increases the risk of vaccines being less effective against it. Mutations can also be more contagious. When these seemingly subtle changes are applied to billions around the world, the results are huge. The situation is particularly risky for countries that have low inoculation rates. Today's anxiety mirrors the early days of the <a href="https://www.thenationalnews.com/uae/2021/10/21/what-is-the-new-covid-19-delta-sub-strain-spreading-in-the-uk/" target="_blank">Delta variant</a> in December last year. The strain did indeed turn out to be more dangerous, with higher transmission rates and perhaps more severe illness, particularly among the unvaccinated. It now represents 99.8 per cent of all cases that the WHO have sequenced in the past 60 days. Beyond health, today's heightened uncertainty is hurting the economy. <a href="https://www.thenationalnews.com/business/markets/2021/11/27/omicron-variant-concerns-rattle-oil-prices-and-global-markets/" target="_blank">The price of oil</a>, for example, fell about 13 per cent on Friday, the biggest decline since the early days of Covid-19. Hotspots face a particularly hard hit. South Africa has already had a difficult year, with high case numbers and widespread riots in July. It was banking on a strong tourism season, which now seems in doubt. The same is true for the rest of southern Africa. Just as people would have been looking forward to Christmas at home, many countries are putting in place <a href="https://www.thenationalnews.com/travel/2021/11/27/omicron-variant-which-countries-are-restricting-travel-to-african-nations/" target="_blank">travel bans to the region</a>. However mild <a href="https://www.thenationalnews.com/coronavirus/2021/11/27/omicron-how-covid-19-variants-are-named-and-classified/" target="_blank">Omicron</a> might be for those fortunate enough to be healthy and vaccinated, it is worth remembering those set to be worst hit. Fortunately, after a year and a half of the pandemic, the measures we need are known. Hygiene measures and wearing masks are as important as ever, as is social responsibility; Dr Farida Al Hosani, a government health spokeswoman, has urged people in the UAE to holiday at home this <a href="https://www.thenationalnews.com/uae/uae-at-50/">National Day</a> and Christmas. Outside the Emirates, promoting vaccine equality is the best tool we have for stopping Omicron and future variants. It is no coincidence that this strain has come about in a part of the world that has low inoculation rates. Less than a quarter of South Africa's population is fully inoculated. All countries must work together to bring up rates in poorer countries. We have been here before, and therefore know what we must do. Whether Omicron takes hold or not, at the most fundamental level it is a reminder that vigilance remains of the utmost importance.