In rich countries, vaccines are making Covid-19 a manageable health issue | Devi Sridhar

  • 5/31/2021
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hen Covid-19 began to spread rapidly in January 2020, governments across the world had limited strategies to deal with it. Without a vaccine or proven treatments for the disease, or even access to mass testing, the only choice political leaders faced was taking the least bad option available. There were four approaches that different governments took during the beginning of the pandemic. China, New Zealand, Vietnam and Thailand chose to eliminate the virus at the cost of stopping international travel. Singapore, Hong Kong and South Korea suppressed the virus through rigorous testing, tracing and isolating while avoiding harsh lockdowns. Sweden allowed the virus to spread through the population before realising health systems could not cope with an influx of Covid-19 patients. Meanwhile, European countries including England and France controlled the virus through a cycle of lockdown measures while keeping borders largely open. This resembled a holding pattern for a plane running out of fuel: people grew tired of continual restrictions, the economy suffered and Covid-19 was never fully suppressed. Before the arrival of vaccines, the most effective of these strategies was the elimination, or “zero Covid”, approach taken by countries such as New Zealand, Taiwan and China. But the tools we have at our disposal have changed radically in the past 15 months. We now have safe and effective vaccines, treatments and mass testing, which permit governments to rethink their initial strategies and form a more sustainable plan for the future. Covid-19 forced governments around the world into a tailspin because of the substantial number of deaths it caused, the burden it placed on health services and the risks of long-term symptoms in younger people. Without lockdown measures in place, the virus could grow exponentially, finding endless hosts to jump between, while fear of the virus caused people to change their behaviour, resulting in economic damage. Vaccines are now addressing these three problems. If governments are able to vaccinate 80-90% of their population, Covid-19 will increasingly become a manageable health issue, much like other vaccine-preventable diseases such as measles or pertussis (whooping cough). We know that vaccines clearly help to reduce hospitalisations and deaths. The US Centers for Disease Control and Prevention found that elderly people vaccinated with mRNA vaccines (Pfizer and Moderna) were 94% less likely to be hospitalised than people of the same age who were not vaccinated. A study in Scotland found that after the fourth week of an initial dose, the Pfizer and AstraZeneca vaccines reduced risk of hospitalisation by up to 85% and 94% respectively. Early research from Yale University also indicates that vaccines seem to help those with long Covid. As many as 30-40% of those who get the vaccines report improvement to their symptoms. If vaccines do indeed prevent people from dying or getting seriously ill, then the end of the pandemic is in sight for the countries that have high vaccine coverage, testing and treatments. One recent study of healthcare workers in Scotland that has not yet been peer reviewed suggests vaccines may also be able to prevent transmission. Israel has raced ahead in its vaccination programme, with the US and the UK not far behind. The European Union is steaming along, and the next group to join them will probably be in east Asia and the Pacific. Once these populations are protected with vaccine-induced immunity, they can start to open up again to the world and lift their border restrictions in a careful and managed way. In these countries, case numbers will become less relevant, as the link between cases, hospitalisations and deaths will be largely broken. This was always the aim of scientists working on treatments and vaccines, and science has succeeded. But there are still two areas of considerable uncertainty. We may yet see the emergence of a variant that reduces the effectiveness of vaccines against death and serious disease. And how we manage the virus in children and adolescents, who will be largely unvaccinated and still susceptible, will be a continuing challenge. It seems inevitable that children under 16 will also be vaccinated (the US has already authorised the Pfizer vaccine to be used in 12-15s). So when will the pandemic be over? Covid-19 won’t end with a bang or a parade. Throughout history, pandemics have ended when the disease ceases to dominate daily life and retreats into the background like other health challenges. Barring a horrific new variant, rich countries such as Britain and the US may be within months, if not weeks, of what their citizens will see as the end of the pandemic. This isn’t the case in poorer countries in Latin America, sub-Saharan Africa and south Asia. For countries that can’t afford vaccines, technology or treatments for Covid-19, populations will remain trapped by outbreaks that cause chaos in hospitals and kill health workers and vulnerable and elderly people. It’s now incumbent on richer countries that are emerging from the pandemic to turn their attention to poorer nations and ensure they have the resources they urgently require. It’s only when Covid-19 stops disrupting lives and livelihoods in all regions that we’ll truly be able to say the pandemic has ended. Prof Devi Sridhar is chair of global public health at the University of Edinburgh

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