Emergency ends

Public health questions about Covid persist, however

Last week, the World Health Organization (WHO) announced it no longer viewed Covid-19 as a “global health emergency”. This announcement comes almost three and a half years after the novel coronavirus first began to spread across the world. In these years, 765 million confirmed cases of Covid-19 have been recorded, and seven million deaths from the disease have been registered. But the WHO, in the same press conference, indicated that its own estimates were that the toll of the pandemic was “likely” more like 20 million deaths. However, after the availability of vaccines and the dominance of milder Omicron-based variants of the virus, the number of deaths has fallen, according to the WHO, from hundreds of thousands of people a week two years ago to about 3,500 a week today.

Experts agree the world must remain on guard for a resurgence of the disease, prompted by additional variants or by other special circumstances. Yet it is now also time for some basic research that can inform public health decisions. For example, the proper use of the vaccines. How many booster shots should be recommended, and at what interval? How long is the immunity provided by current versions of the vaccine, and is there funding available to keep modifying booster shots to keep up with the virus’ mutations? The existence of vaccines and the number of individuals who have received them is not the end of the story. These were rolled out on an accelerated timetable in a triumph of human ingenuity — but the time has now come for the evaluation of their long-term effectiveness.

There are also questions that can and must be asked about the long-term effects of the disease itself. The WHO has a formal definition of what constitutes a clinical case of “long Covid”, but there are no specific ways in which this apparent syndrome can be identified through tests or other biological markers. Long-term and follow-up studies of those who reported long Covid symptoms, especially incapacitating fatigue, will be necessary. International co-operation in these efforts will be as key as it was at the height of the pandemic. Individual governments and health authorities should not need to duplicate their investigations of the longer-term effects of the disease, but share information on their findings so that public health systems globally can respond.

The final question of course must be: Has the world learned what it should have? Vaccines were discovered at the most optimistic timetable imaginable, and most studies indicate they have worked even more effectively than was hoped for. This has been an unalloyed success. But the delay in spreading these vaccines across the world, as well as the lack of capacity to increase manufacturing and of financial resources to pay for them, should have been a wake-up call that the world needs to do better. Many countries in the developing world will have developed a deep-rooted sense of alienation from a global system that ignored their desperate need for vaccines at the height of the pandemic. Over the next few years, as a result of demographic surveys and censuses, the world must also be given a more reliable sense of the excess mortality caused by the pandemic. That tragically large number must be a spur to greater efforts at co-ordination on public health.