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A Cuban reads a newspaper with articles about the late Venezuelan President Hugo Chavez, on March 6, 2013 in Havana.

HAVANA — Cubans remember the so-called Special Period of the 1990s, when the Soviet Union's sudden collapse plunged the island into years of economic depression, with cars and buses disappearing from the streets for lack of fuel and rolling blackouts leaving the capital in darkness.

Now Cubans fear a return of hard times following the death of Venezuelan President Hugo Chavez, whose billions of dollars of oil largesse helps the island's economy function. Some Havana residents were even talking about hoarding candles on Wednesday.

Francis Gomez, a 22-year-old tourism student from the city of Pinar del Rio, said she was "scared and worried."

"Ever since Chavez became ill, my parents have been saying, 'Please, God, don't let there be another Special Period'," she said.

While Chavez's party remains in power in Venezuela, and his political allies have said they won't change the program, at least not in the short term, a victory by the opposition in a presidential election expected in the coming weeks could change the game entirely. Opposition leader Henrique Capriles has said he would reevaluate the program if elected.

Cubans are not alone in having worries following Tuesday's death of Chavez, who used Venezuela's oil wealth to aid allies through a part-ideological, part-humanitarian program that gives out petroleum at preferential terms.

More than a dozen other countries in Latin America and the Caribbean, many of them economic minnows, have benefited to the tune of billions of dollars from the Petrocaribe pact that was created in 2005 with the goal of unifying the regional oil industry under Venezuelan leadership and countering U.S. influence.

Cuba alone receives about 92,000 barrels of Venezuelan oil a day to meet half its consumption needs, worth around $3.2 billion a year, according to an estimate by University of Texas energy analyst Jorge Pinon.

Havana pays about half the bill through a barter exchange in which tens of thousands of doctors, teachers and other advisers provide services in Venezuela. The rest goes into 25-year credits with 1 percent interest.

"There's no cash exchange. They don't have to write a check. That's the importance of this agreement," Pinon said. "It represents $3.2 billion of free cash flow to the Cuban economy."

"If a new Venezuelan government turns that into a true commercial agreement where in 30 days you pay 100 percent in cash for what you owe, it would be a substantial economic impact to both Cuba and to Petrocaribe countries, no question about that," Pinon said.

Nicaragua, perhaps the second-most dependent on Venezuelan oil after Cuba, gets nearly all its 12 million barrels a year from Caracas, worth about $1.2 billion, said Nestor Avendano, an economist and president of the consulting firm Consultores Para el Desarrollo.

President Daniel Ortega, a staunch Chavez ally, pays about half up-front and finances the rest over 23 years at 2 percent annual interest.

La Prensa, Nicaragua's leading newspaper, noted in an editorial that Ortega has been trying to shore up economic reserves in recent months and raised taxes in January, apparently in anticipation of a reduction in Venezuelan aid.

The Dominican Republic gets just over 40 percent of its oil through Petrocaribe, and saves roughly $400 million a year from the arrangement. Struggling Jamaica, where debt is a whopping 140 percent of gross domestic product, gets roughly two-thirds of its crude through Petrocaribe.

Venezuelan largesse peppers the Caribbean
Across the Caribbean, it's the same story one island nation after another.

"Petrocaribe saved several Caribbean economies from certain collapse," said Anthony Bryan, a senior associate at the Center for Strategic and International Studies in Washington and an expert on U.S.-Caribbean relations.

Nicolas Maduro, Chavez's handpicked successor and a firm ideological ally of Cuba, is seen by analysts as more likely to win the election to replace Chavez. But in the absence of Chavez, who kept his political base in line through pure politics of personality, Maduro might come under pressure as he tries to control factions that don't always agree.

"I think that there's going to be a potential drop in Venezuelan willingness to sell oil (at preferential terms) because Maduro is going to be facing his own internal schisms," said Gregory Weeks, a political scientist specializing in Latin America at the University of North Carolina at Charlotte. "I think he's going to have to be paying more attention to directing resources to his own constituencies at home, rather than abroad."

Weeks added that Maduro would likely try to maintain the Cuba subsidy as much as possible for symbolic reasons, and many analysts say the island is less dependent on Venezuela than it was on the Soviets.

Shortages, inflation at 22 percent
But Venezuela's economy has problems that Chavez's successor will have to deal with. Inflation is 22 percent, dollars for imports are scarce amid currency control and residents complain about sporadic shortages of basic goods.

"Once Venezuela's budget deficit really begins to bite in a way that can no longer be ignored, then the government will have to make some tough decisions in term of spending," said Eric Farnsworth, an energy specialist with the Council of the Americas. "And one of the quickest ways to cut in any country is foreign aid."

For some Petrocaribe beneficiaries that might simply mean tightening belts. For others it could mean rising discontent or even potential unrest as popular social programs wither.

Nicaragua's Ortega, for example, has used the extra cash to put roofs on homes and finance health care and education in a country where 80 percent of the people live on less than $2 a day. Economist Rene Vallecillo said the country could see a 1 percentage-point drop in GDP growth if Venezuelan aid disappeared.

Haiti has used millions in Venezuelan aid to pay for fuel, renovate power stations and build low-income housing in the earthquake-torn nation.

Jamaica has used the 22,000 barrels of Venezuelan oil it got every day in 2011 to produce 95 percent of its electricity.

"If it's 95 percent of your power generation, that has broader implications in terms of your social well-being," Farnsworth said. "They're really going to hurt. ... This has been a lifeline."

Nicaragua's tallest volcano has belched an ash cloud hundreds of feet into the sky in its latest bout of sporadic activity, prompting the evacuation of nearby residents, the government said on Wednesday.

The 5,725-foot San Cristobal volcano, which sits less than 100 miles north of the capital, Managua, in the country's northwest, has been active in recent years and went through a similar episode in September.

The latest activity began late Tuesday.

Government spokeswoman Rosario Murillo called on residents who live within a two-mile radius of the volcano to leave the area. About 300 families live near the volcano.

"We have some families who have self-evacuated. ... We ask (the people) to go to a safe place. It's just for a few days during this emergency," she said, adding that it was a precautionary measure.

A billowing grayish cloud could be seen drifting sideways from the volcano's peak.

The volcano also stirred in mid-2008, when it expelled gas and rumbled with a series of small eruptions.

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CHICHIGALPA, Nicaragua – You won’t see a road sign pointing to “La Isla de Viudas,” or “The Island of Widows,” as it’s not the community’s official name. It’s a nickname born from a horrific body count. 

In the past 10 years, it’s believed that hundreds, if not thousands, of residents of Chichigalpa — mostly male sugarcane workers — have died from chronic kidney disease, or CKD. That in a city of nearly 60,000, roughly the size of Ames, Iowa. 

The mysterious and hidden epidemic, first highlighted by the Center for Public Integrity, has claimed thousands more lives across Central America. In El Salvador and Nicaragua alone, the number of men dying from the excruciatingly painful disease has risen five-fold in the last two decades. High rates of CKD also have been found in rural villages in India and among the rice paddies of Sri Lanka.

Sacorro Mendez Flores, who lives in the “La Isla” district of Chichigalpa, remembers when her son first fell ill. Jorge Luis Silva didn’t look sick at first, but inside he was dying. His kidneys struggled to filter waste from his body, to no avail. Five months ago, Flores buried him. 

“The same thing happened to my husband,” she said. “They both died the same.”

Sacorro Mendez-Flores, surrounded by her grandchildren, holds a family photo. The resident of Chichigalpa, Nicaragua, lost both her son and husband to chronic kidney disease.

Researchers are searching for answers about why this disease is ravaging not only the bodies of its victims, but the communities they leave behind. 

The illness spreads
More than 20 million Americans aged 20 and older have chronic kidney disease, according to the Centers for Disease Control and Prevention. In developed countries like the U.S., CKD often goes hand in hand with obesity, diabetes and hypertension. With treatment, including dialysis and kidney transplants, many with the disease survive. 

The CKD plaguing parts of Central America, however, is something scientists have never seen before.

“It affects people who don't have diabetes or hypertension, which are the usual risk factors for chronic kidney disease,” said Sasha Chavkin, a CPI reporter who has covered the mysterious epidemic for several years. “No one can figure out what it is that's making all these people sick.”

Slideshow: Mysterious malady fells sugarcane workers

Estbean Felix / AP

Workers in Central American sugarcane fields are dying of chronic kidney disease at an astonishing rate and experts are unable to say why.

Launch slideshow

“It comes at great social, economic and humanitarian cost,” said Dr. Daniel R. Brooks, an associate professor of epidemiology at the Boston University School of Health who is leading a research team looking for the cause of the epidemic. “These are working-age people who are being struck down, and whole communities are really hurt and devastated by this disease.” 

And with little or no access to the life-saving treatments available in the developed world, a CKD diagnosis is often tantamount to a death sentence. 

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In Nicaraguan sugarcane community, workers stare death in the face

Chronic kidney disease: 'Silent killer' may have multiple triggers

“Where we stand right now is that ultimately this disease is not treatable in this community,” said Nate Raines, a researcher with the Mt. Sinai School of Medicine Global Health program, which is collaborating with two organizations in Nicaragua on research independent from the Boston University group. “What we need to do is find the cause. That's the only way to really help the health situation.” 

Many in Chichigalpa believe that the root of the disease lies in chemicals sprayed in the sugarcane fields while men are working, or seeping into the water supply. A spokesperson from the sugar industry says the chemicals used are standard fertilizer and are not used to excess.  

Science, so far, points to a more complicated answer. 

'Markers' of kidney damage found
The research team from the Boston University has linked the disease in Central America to strenuous labor, dehydration and environmental conditions in which chemicals may play a role. That theory was supported by the group’s most recent study, which found “markers” of kidney damage in adolescents as young as 12 in affected communities. 

Thousands of miles away, research in Sri Lanka’s affected communities also indicates chemicals may play a key role in the illness devastating communities there.

As reported last month by the Center for Public Integrity, the country’s health ministry and World Health Organization announced in June that a years-long study had identified chemicals thought to be an essential cause of the disease: cadmium and arsenic. Both are heavy metals found in fertilizers and pesticides that can cause an array of health effects, including the type of kidney damage ravaging communities in Sri Lanka and Nicaragua.

While most of those tested had lower levels of the toxic elements than officially designated as dangerous by the United Nations, researchers believe that long-term exposure, likely through the food chain, may explain the high incidence of CDK. 

The findings, due to be officially released in October, represent a potential breakthrough in the research about CDK worldwide, including the epidemic in Nicaragua. 

Researchers in Central America have not pinpointed a chemical cause. But the new research on adolescents indicates the kidneys of those going into the fields may already be damaged, making the long days and repeated dehydration in the fields potentially deadly. 

Some experts also suggest that sugarcane workers may also unwittingly be harming themselves as they struggle to stay hydrated while cutting up to 11 tons of cane a day by hand.

For a refreshing pick-me-up, they occasionally slice a stalk of cane, peeling back its “bark” and sticking it in their mouths, where it produces a sweet sugary liquid. 

But investigators now wonder: Could that constant flow of sucrose, combined with 90-plus degree temperatures and severe daily dehydration, be a deadly cocktail that slowly brings on CKD? 

“We believe high amounts of sugar solutions may not cause much kidney damage,” said Dr. Richard Johnson, head of the division of renal disease and hypertension at the University of Colorado, Denver. “But under certain circumstances, such as dehydration, we’re concerned the sugar may actually be toxic in causing damage to the kidneys.”

The sugar link
Whether or not sugar consumption plays a direct role in causing the Central American form of CKD, activists say it is a thread that connects the disease to its northern cousin.

In the U.S., rampant sugar consumption – Americans eat an average of 22.2 teaspoons of sugar per day according to the American Heart Association—drives many of the diseases linked to CKD, including diabetes and hypertension. 

And with recent steep increases in the price and demand for sugar, more people are working longer hours in the sugarcane fields of Central America. In 2011, the U.S. imported 330,000 metric tons of raw sugar from Central America, or nearly one-quarter of total raw sugar imports that year, according to the United States Department of Agriculture.

“Not only is the production of sugar killing people, but the consumption of it is killing people,” said Jason Glaser of La Isla Foundation, a nonprofit group he founded to focus attention on the epidemic and fund research that he hopes will solve the mystery. “It's bad for you and it's bad for workers.” 

The sugar industry, however, rejects suggestions that it is causing the epidemic of CKD among workers at its mills and plantations.

“We are not responsible for it,” said Mario Amador, a spokesman for the sugarcane industry. “We’re working to find a solution.”

He also blames the workers themselves, saying they drink too much alcohol. “It’s part of our culture,” Amador said. “It’s part of the things we do in our country. Poor people do it a lot.” 

Amador also speculated that active volcanoes in the region could have contaminated the water supply. But he admits he does not know why so many have died from CKD.

No matter what the research finds, Central America is unlikely to curb its cane production anytime soon. The world market for sugar is strong, and the industry receives direct help from abroad. 

The International Finance Corp., the private-sector arm of the World Bank, has provided loans of more than $100 million to promote production and biofuel in Nicaragua in recent years. Though the loans went to two plantations whose workers have been heavily affected by kidney disease, they were approved without formal consideration of the disease because the IFC did not find a link between the cane fields and CKD, according to the Associated Press. 

After workers complained about the loans, the IFC helped to negotiate an $800,000 donation to sponsor the ongoing Boston University study, the Center for Public Integrity reported. The money was provided by Nicaragua Sugar Estates Limited, a major sugar producer in the west of the country, part of more than $4 million it has committed toward research and community development in recent years.

Waiting to die
But for many in Chichigalpa, the results of the research – whatever they may be – will come too late. 

Like most of the men in this community, Maximiliano Lopez, spent years in the fields cutting sugarcane. He began at 5 a.m., when the air was cool, and continued to work as the sun beat down, sometimes logging 14 hours a day. Then he was informed he had CKD.

Even after his diagnosis, which bans him from working in the fields or at the mill, the muscular 32-year-old said he used a friend’s identification to return to cutting cane. Nicaragua is the second-poorest country in the Western Hemisphere, he explained, and many workers continue to work the harvest after being diagnosed with kidney disease because it is the only work they can find. 

“A lot of people do it out of necessity,” Lopez said. “They have a big family and they're the head of the household, so even if they're sick, you have to find work to support your family.” 

But, as Lopez and other cane workers eventually discovered, short-term survival may mean leaving behind the families that they labored so mightily to support.

“I began working there to earn a living and instead I earned death,” he said. “I’m just waiting for the day to come.” 

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