Under international urban search-and-rescue protocols, neighbors are considered the first emergency responders before professional rescue teams arrives, said Jacobo Vidarte, an emergency management specialist in Venezuela.

But in Venezuela, volunteers, who sometimes lack training and appropriate equipment, make up roughly 70 percent of those involved in disaster response because the country has so few teams, Mr. Vidarte said.

The weaknesses long predated the earthquake.

Experts said Venezuela’s emergency and health systems have deteriorated after more than 25 years of chronic underinvestment and a lack of long-term planning.

The country’s economic crisis accelerated a mass exodus of experienced firefighters, nurses and physicians as public-sector salaries cratered. Equipment fell into disrepair and hospitals struggled with chronic shortages of electricity, running water and medical supplies.

More than 60 percent of Venezuelans lacked regular access to health care before the earthquake, according to a report by an independent humanitarian platform, Hum Venezuela.

Experts say Venezuela still has trained and dedicated medical and emergency personnel, but not enough of them — or the resources and specialized equipment needed to respond to a disaster of this scale.

“Their salary is so low that they pay to go to work,” said Dr. Lorenzo.

For years, the government has also placed political appointees rather than technical experts at the head of many institutions, said José Araque, a geographer at the University of the Andes who studies disaster risk.

Venezuela’s scientific institutions, he added, have long identified seismic risks and produced recommendations, but successive governments failed to translate that work into public policy.

International humanitarian groups say years of political isolation also complicated the response.

Phil Gelman, Latin America director for GOAL, a humanitarian organization that operates health programs in Venezuela, said groups like his spent years operating quietly in the country because of the government’s hostile relationship with civil society, limiting the institutional relationships they normally rely on during disasters.

“We were working in the shadows,” he said. “That doesn’t get undone overnight.”

Janeth Márquez, director of the Venezuela chapter of the Catholic charity Caritas, said the country’s response has suffered from years of weak coordination between government agencies and nonprofit organizations.

“The earthquake didn’t collapse the health system,” she said. “We already had a collapsed health system.”

Carlos Alvarado, Venezuela’s health minister, said in televised remarks that the government had mobilized more than 5,000 health workers and integrated military, public and private hospitals in a unified response.

“We have managed to provide optimal care to the patients,” he said.

Tibisay Romero contributed reporting from Valencia.