– After the other villagers had drifted away to do chores, Rafael Pequeño found himself alone with the headman and opened his notebook.

It had been two years since Pequeño, a nurse, had visited this poor indigenous village in Venezuela’s remote Orinoco Delta region. His notebook contained a registry of patients in an HIV treatment program that, like the rest of the nation’s public health system, had fallen apart. Pequeño took a roll call.

“Armando Beria,” he said.

“Still here,” replied the headman, Ramón Quintín.

“Ebelio Quinino,” the nurse said.

“Still here.”

“Mario Navarro.”

“Dead.”

“Wilmer Medina.”

“Dead.”

Of the 15 villagers who had been part of the program, five had died of AIDS, the disease caused by HIV. In all, more than 40 residents had died of AIDS or AIDS-like symptoms in the past several years — in a settlement of only about 200.

“It’s wiping out this community,” Pequeño said.

In recent years, amid profound shortages of medicine coupled with widespread ignorance, HIV has spread rapidly throughout the Orinoco Delta and is believed to have killed hundreds of the Warao indigenous people. The government has ignored the issue, medical specialists say, leaving the isolated and deprived population to face an existential threat alone.

Dr. Jacobus de Waard, an expert in infectious diseases, said that nothing less than the future of the ancient culture was at stake.

“If there’s no intervention, it’s going to affect the existence of the Warao,” he warned. “A part of the population is going to disappear.”

The epidemic is a crisis within a crisis, an example of how Venezuela is failing to grapple with a resurgent AIDS emergency. Under the presidency of Nicolas Maduro, which began in 2013, the economy has crumbled, causing crippling shortages of medicine and diagnostic tests, and compelling many of the best doctors to emigrate. The administration did not respond to requests for interviews.

The government has even stopped distributing free condoms, which can help prevent the spread of HIV, activists say. The price for a pack can cost the equivalent of several days of minimum wage.

AIDS activists and specialists say that HIV infection rates and the number of AIDS-related deaths have skyrocketed. So, too, has the number of once-stable patients whose health has collapsed without antiretroviral drugs.

“It’s a humanitarian emergency — we have to be very emphatic,” said Jhonatan Rodríguez, president of StopVIH, an activist group.

Among the most disadvantaged Venezuelans, he said, are the Warao. “It’s a population that has been totally neglected.”

A study published in 2013 warned of a burgeoning epidemic. It found that nearly 10 percent of Warao adults living in eight villages tested positive for HIV. In one community, about 35 percent of those tested were HIV positive. By comparison, HIV prevalence among adults in South and Central America was 0.5 percent.

Worsening matters, the type of virus that had entered the population was particularly aggressive.

Bishop Ernesto José Romero said he has spoken with officials about the crisis, to little effect. “We have a government that wants to silence everything,” he said. “They say it will be resolved. But more and more people die.”