War and disaster often capture the headlines, but another kind of catastrophe, the invisible spread of disease, is as lethal and heartbreaking. As chaos envelops Venezuela, bringing hunger, food shortages, hyperinflation and flight by millions of people, disease is following.

Sicknesses that were once eliminated in Venezuela and are easily prevented by vaccine are breaking out routinely. According to the Pan American Health Organization, from June 2017 until this September, measles cases skyrocketed, with 5,500 confirmed cases and 64 deaths, compared with one case recorded in Venezuela between 2008 and 2015. More than 1,200 diptheria cases have been confirmed from July 2016 to this September, leading to more than 200 deaths; there wasn’t a single case of diptheria from 2006 to 2015. Suspected and confirmed malaria cases in Venezuela shot from nearly 36,000 in 2009 to more than 406,000 last year because of a fall-off in mosquito-control activities and shortages in medication. The 2017 incidence rate of tuberculosis was the highest seen in Venezuela in 40 years. And an estimated 87 percent of HIV patients registered to receive retrovirals are not getting them.

These are grim statistics; the reality is also etched in suffering felt by millions. Food shortages leave people more vulnerable to disease. According to a recent report by Human Rights Watch, all signs point toward more malnutrition and hunger. A survey by three universities in Venezuela found that 80 percent of households are food-insecure, “meaning they don’t have a reliable source of food, and that people surveyed had lost an average of 11 kilograms,” or about 24 pounds, in 2017, the group reported.

Venezuelans are running for their lives. The Post recently reportedthat aid agencies think nearly 2 million people will abandon their country this year, in addition to the 1.8 million who left over the past two years. The tide of refugees is spreading disease to neighboring Colombia and Brazil, where hospitals are “overwhelmed by a surge of sick Venezuelans” seeking treatment for illnesses such as cancer and HIV that they cannot get at home.

Venezuela has imploded under the ruinous hand of President Nicolás Maduro and his predecessor Hugo Chávez, with help from Cuba. To their legacy of failed socialist policies, corruption, mismanagement and political repression must now be added the destruction of public health in an oil-rich nation once among the continent’s most developed.

Mr. Maduro’s regime has met the chaos by refusing humanitarian aid offers from abroad while broadcasting mindless propaganda at home, denying there is a crisis. He told the United Nations in September that Venezuela “is the victim of world media attacks designed to construct a supposed humanitarian crisis so as to justify a military intervention.”

Millions of his people know this is not true, that the humanitarian crisis is real and not “supposed.” At the very least, he should open the gates to desperately needed food and medicine.

— The Washington Post