Measles infections in the US have reached a record 33-year high. The forces that spread diseaseVaccine hesitancy is no longer on the margins: it is a public health emergency. Longer winters allow ticks and mosquitoes to survive longer, increasing the spread of Lyme disease, dengue fever and malaria. The future of public healthWe already have the answers to prevent many of these crises, or at least manage them. Public health messaging is effective.