On Saturday, WHO Director General Dr Tedros Adhanom Ghebreyesus made the extraordinary decision to declare the rapidly expanding monkeypox outbreak as a global emergency. He did so despite a lack of consensus among colleagues, the first time such a process has been followed in the organisation’s history. It is a sign of quite how worrying he and many other medics deem the situation. Other illnesses to have merited emergency designation include coronavirus, ebola and polio. Monkeypox involves similar symptoms to smallpox, such as fever, rashes and lesions. Recently, about 65 countries where monkeypox is not endemic have reported outbreaks. The US Centres for Disease Control and Prevention says that more than 16,000 cases of the viral disease have been reported in 74 countries since May, although deaths have only been recorded in Africa, particularly Nigeria and the Democratic Republic of Congo, where the disease was first discovered in the 1970. Declaring a global emergency means the WHO fears the outbreak could now spread internationally, therefore requiring a co-ordinated response. In the wake of such an intense warning, it is hard not to think back to the troubling early days of Covid-19, when medics around the world began to understand the scale of the emergency, and, indeed, when Dr Ghebreyesus’s organisation faced accusations that it did not act swiftly enough. But his warning last week is different, and there are no reasons yet to fear monkeypox becoming as devastating as Covid-19. Temporary recommendations given by the organisation relate mostly to the need for international collaboration and co-operation to prevent the situation deteriorating. This ranges from establishing global disease surveillance to increasing awareness among medical staff all over the world. Co-ordination between medical communities around the world will be vital. Much of what experts are demanding goes wider than just monkeypox itself. For example, Dr Placide Mbala of the global health department at Congo’s Institute of National Biomedical Research stresses the need for overcoming inequality in global vaccine distribution: “Vaccination in the West might help stop the outbreak there, but there will still be cases in Africa. Unless the problem is solved here, the risk to the rest of the world will remain.” A new vaccine has been approved for monkeypox, but other well-established ones used for years to suppress smallpox are also effective. But the outlook for global vaccination campaigns – when vital doses such as these are administered – is currently bleak. The week before its monkeypox designation, the WHO highlighted data that shows how global vaccination coverage continued to decline throughout 2021 due to the Covid-19 pandemic. This means that 25 million infants missed out on lifesaving vaccines, the kind that will ultimately protect the world from resurgent, previously contained diseases such as monkeypox, as well as new ones. A senior Unicef official called it the warning “a red alert for child health”. As monkeypox spreads, its significant medical dangers are clear. But perhaps more consequential is the way governments around the world do or do not respond to it. There are no expectations that it will rival the devastation of Covid-19. But if the international community does not act now, it may, like the pandemic, turn out to be another deadly burden that could have been stopped, or at least significantly mitigated.