Many neurological diseases have been linked to malnutrition. Scientists believe that drastically low calorie diets and the lack of vitamins A and B, folic acid, and animal fats are prominent factors that cause poor health -- including eye diseases. This essay sets out to analyze the state of Cuban health, particularly regarding vision acuity, and whether vision acuity has been affected by the severe limitation of food and medicine exports due to US embargoes.

The U.S. embargo against Cuba began two years after the 1959 Cuban Revolution. Initially, the embargo had a limited impact on Cuba, because of Soviet assistance to the Caribbean island nation. For three decades after the revolution, seventy to ninety percent of Cuba’s international trade was with the Soviet bloc [1]. From 1965 to 1975, the Cuban economy increased at an annual rate of two percent, and in the following fourteen years, the annual rate doubled to four percent per year [1]. However, the dissolution of the Soviet Union and the Community for Economic Cooperation (COMECON) trade group greatly weakened the Cuban economy. Between 1989 and 1993, the Soviets reduced their exports to Cuba by seventy percent. This resulted in Cuba’s gross national product (GNP) falling thirty-five percent during those years [1]. The worth of imports to Cuba from all suppliers lessened from eight billion dollars to 1.7 billion dollars [1].

As if things were not bad enough for Cuba, in 1992 the United States passed its Cuban Democracy Act, making the embargo even stricter. All U.S. supplementary trade, including barter of food and medicines, has since been forbidden. The U.S. does not allow ships from other countries to dock at its ports for six months after visiting Cuba, and it also pressures nations to terminate trade with Cuba or to supply the island with humanitarian goods. “Although embargo legislation since World War II has usually included exemptions from humanitarian good, the 1992 embargo legislation on Cuba does not permit sales of food and requires unprecedented ‘on-site verification’ for the donation of medical supplies” [1]. Cuba is permitted to purchase medicines from the U.S. companies and foreign suppliers; however, the United States has frequently denied those requests. “The Cuban government estimates at around 60 billion dollars the total losses suffered by the local economy due to the sanctions applied by the United States over the past 40 years, 1.2 billion dollars of which correspond to the health sector” [2].

The U.S. imposed its embargo against Cuba after Fidel Castro nationalized all American properties without compensation, vowed to spread his revolution to the rest of Latin America, and allied his country with the Soviet Union. The purpose of the embargo was to reprimand Cuba for the expropriations and to increase the cost to the Soviet Union of upholding its recent relationship with Cuba [3]. However, the embargo has caused the Cubans far worse problems than perhaps originally intended. After a year-long investigation, in 1997 the American Association for World Health declared that the U.S. embargo has severely harmed the health and the nutrition of countless ordinary Cuba citizens [4]. “‘The embargo against Cuba is one of the few embargoes that includes both food and medicine and it has been described as a war against public health with high human costs,” Barry [professor of medicine and public health and director of the Office of International Health at Yale School of Medicine] wrote in an article published January 18 in the Annals of Internal Medicine” [5]. It defies the fundamental international charters and conventions concerning human rights, including the United Nations charter, the charter of the Organization of American States, and the articles of Geneva Convention regulating the treatment of civilians during wartime [4].

Four aspects of the U.S. Congress’ 1992 Cuban Democracy Act contributed to the degradation of Cuba’s medical system. First, the Ban on Subsidiary Trade imposed in 1992 prohibited countries other than the United States from trading with Cuba, severely constraining Cuba’s ability to import medicines and medical supplies from third-country sources [4]. Second, the Licensing under the Cuban Democracy Act discouraged any medical trade between U.S. and Cuba [4]. “Numerous licenses for medical equipment and medicines have been denied on the grounds that these exports ‘would be detrimental to U.S. foreign policy interests’” [4]. Third, the embargo did not allow non-U.S. ships to load or unload cargo in U.S. ports for six months after they delivered goods to Cuba, thereby strongly discouraging transporters from delivering medical equipment to Cuba [4]. Lastly, the 1992 Cuban Democracy Act dissuaded other countries from providing humanitarian aid to the island nation [4].

Is it any wonder, then, that a rare — and, to an extent, mysterious — eye disease afflicted the vision of thousands of Cubans, with its greatest impact from 1992 to 1994? The Ministry of Public Health of Cuba (MINSAP) recognized 50,862 cases of neuropathy in Cuban populace from January 1, 1992 through January 14, 1994 [6]. The neuropathy included an optic form, characterized by sub-acute beginning, decreased visual acuity, color blindness, and/or central cecocentral scotomata. It also included a peripheral form, characterized by a painful burning sensation in the hands and feet, loss of tendon reflexes, easy fatigability and muscle pains. Both forms have been accompanied by significant weight loss and exhaustion [6]. “The 50,862 cases accounted for a national cumulative incidence of 461.4 per 100,000 persons . . . Of these, 26,446 (52%) had the optic form . . .” [6]. Victims whose symptoms met either the optic case definition or both the optic and the peripheral case definitions were categorized as having the optic form. The optic form predominated among males, specifically those aged forty-five to sixty-five [6].

Patients affected by optic neuropathy had symptoms of blurred vision, photophobia with progressive vision loss in both eyes, and visual acuity varying from medium (20/80) to critical loss (5/400) [7]. Ishihara color tests indicated a loss of awareness of green and red colors, and “tangent field tests with white target indicated central scotomata (up to 5 degrees) that were larger when testing with red and green targets (up to 8 degrees from fixation), often showing cecocentral scotomata” [7]. After numerous clinical studies, patient blood samples revealed reduced levels of vitamin B12.

In Cuba, the clinical response of patients with neuropathy to vitamin supplementation suggests that diet may be significant in this epidemic and may provide a clue to its cause. Economic difficulties in Cuba led to widespread changes in dietary patterns. For instance, Cubans consume far less meat, dairy products, oils, and fats than they did before government rationing. Food rations are meant to last for over a month but only last ten days [8]. Everyone is allowed only four eggs every fifteen days. Vegetables and fruits hardly make their way onto the market—possibly once a month, and then not every month [8]. Whole and powdered milk are rationed in inadequate amounts, just like other foods, so most children drink condensed or evaporated milk [8]. Meat is rarely available, and when it is, it is usually granted to children under the age of seven years. This is significant because, according to the New England Journal of Medicine, “A strict vegan diet -- defined as avoiding the consumption of all animal products -- may lead to deficiency of important vitamins that are critical to eyesight.”

After numerous clinical studies, Cuban blood samples revealed reduced levels of vitamin B12. “Thomas Hedges, an associate professor of ophthalmology and neurology at Tufts University and a member of the US & Cuba Medical Project, says that “the limited availability of food caused by the end of Soviet financial support and a continued US trade embargo ‘suggested the epidemic may be associated with the lack of certain nutrients’” [9]. The evidence suggests that a lack of the vitamin B complex or of folic acid is at the core of the disease. The B-complex is made up of a group of eight distinct B vitamins [10]. The body requires vitamins in small amounts, extracted from foods, beverages, and the bacteria within our bodies. “The B-complex vitamins are actually a group of eight vitamins, which include thiamine (B1), riboflavin (B2), niacin (B3), pyridoxine (B6), folic acid (B9), cyanocobalamin (B12), pantothenic acid and biotin” [10]. These vitamins are crucial for eyesight and other bodily functions. The B-complex vitamins are found in “brewer’s yeast, liver, whole-grain cereals, rice, nuts, milk, eggs, meats, fish, fruits, leafy green vegetables…,” and are present in very limited amounts in Cuba because of the U.S. embargo [10]. Vitamin B12 deficiency is often seen in strict vegetarians. In Cuba, B12 is essential for processing carbohydrates, proteins and fats—abundant in the local diet. This vitamin is also essential for maintaining nerve sheaths vital to the nervous system [10]. Because the B12 vitamin is nearly inexistent in the Cuban diet, the absence may explain the nerve damage found to be associated with the epidemic. An adequate intake of folic acid is also important, because it interacts with the B12 vitamin in the synthesis of DNA, fundamental for all body cells. “Deficiencies are found mainly in alcoholics, the malnourished, the poor…” [10].

The disorder is neither contagious nor fatal, but it has caused irreversible damage to eyesight. “‘The epidemic is unique in the speed of its onset and the large numbers of those stricken’” [11]. Alfredo A. Sadun, a neuro-ophthalmologist from the University of Southern California School of Medicine and the Doheny Eye Institute, examined patients and found optic nerve injury related to that found in several other central-nervous-system diseases including damage to the mitochondria [11]. In order for the mitochondria to produce energy, the body requires large quantities of folate, or folic acid, which is contained in animal liver and in fruits and vegetables, all of which are severely rationed in Cuba. Folate also helps the body eliminate such toxins as methanol—found in small quantities in alcoholic drinks. As Rovner states in her article, “‘Normally,’ said Sadun, ‘small amounts of methanol wouldn’t bother you, but because the Cubans have a low folate level because of their poor diet, the little folate that’s left is being sucked out of the system to be used to detoxify the methanol’” [11]. Another toxin that disturbs energy-producing mitochondria is cyanide, which is found in small amounts in poorly processed sugar cane, a key element in rum [11]. Because rum is rationed in Cuba, locals brew their own beverage at home to avoid legal complications. The combination of methanol and cyanide in the homemade rum has greatly contributed to the epidemic.

To make matters worse, tobacco is a source of cyanide, and ninety-five percent of adult Cuban males are smokers [11]. Toxins from cyanide or cyan glycosides in tobacco can be worsened by relative deficiencies of B-vitamins and sulfur-containing amino acids, which are responsible for the detoxification of these poisonous compounds. “The epidemic began in late 1991 in a tobacco-growing region west of Havana. It gradually moved east as first men, then women and some children, mostly adolescents, began to turn up with vision loss in varying degrees and loss of sensation in arms and legs” [11]. Although the Cuban government took notice of the baffling epidemic and ordered immediate door-to-door distribution of nutritional supplements, most of the affected persons will never recover their vision because their eye nerve fibers have been dead for over a year. Even with proper nutritional care, most nerve fibers will never be restored.

Studies conducted in Cuba indicate yet another baffling visual impairment found among Cuban babies. It is called retinopathy of prematurity (ROP), with 38.6 percent occurrence rates reported in Cuban children [12]. This illness is found in babies who are born premature or with significantly low weights. It leads to scarring on the retina of the developing eyes, and it deteriorates sight progressively, until, if left untreated, the child goes completely blind. Results point to a connection between low folic acid levels in the diets of pregnant women and ROP. As mentioned earlier, folic acid is a very important component of the vitamin B-complex, and it is found in yeast, liver, green vegetables, whole grain cereals, and other foods. The need for folic acid increases during pregnancy, because of the high demands of the vitamin by the fetus. “Doctors often suggest a 300 mg. daily supplement for pregnant women” [10]. Folic acid, just like many other vitamins, should be slightly increased during pregnancy and breast milk production. But because foods rich in folic acid are lacking in the Cuban diet due to severe rationing and limitation of supply in the country, both expectant mothers and fetuses are adversely affected. The long-term effect of insufficient folic acid dosage leads to vision impairment and even blindness in children born before term or with significantly low birth weights. Because the U.S. embargo cuts off Cuba’s sources for many foods, including those rich in vitamin B-complex, the vision acuity of Cuban citizens, young and old, is impaired.

Public health and universal access to free medical care have been top priorities of Fidel Castro’s governmental agenda since 1959. “General practitioners and nurses deliver preventive care through the Family Doctor Program; one physician and one nurse are personally responsible for each neighborhood of 100 to 200 Cuban families” [13]. The Cuban government has even been able to successfully gather enough vitamins to distribute to their citizens in response to the epidemic. “$181,000 was spent to transport vitamins to Cuba; it is estimated that the cost would have been approximately $56,000 had these vitamins come from the United States” [1]. For several decades the U.S. embargo has resulted in these kinds of financial hardships on the Cuban health care system. Especially from 1989 to 1993, there was a severely sharp decrease in the amount of money allotted for the import of medical necessities. “The dollar value of imports for health fell from $227 million in 1989 to $67 million in 1993” [1]. Since 1992, the number of unmet medical needs and the lack of essential drugs and medical equipment have risen. This is directly linked to the fact that in 1992 the Cuban Democracy Act strictly prohibited the sale of food, medicines, and medical supplies to Cuba. Since then the island’s once preeminent model health care system has become threatened by shortages of all sorts. “Of the 1,297 medications available in Cuba in 1991, physicians now have access to only 889 of these same medicines– and many of these are available only intermittently” [4]. Aspirin is about the only medication that is accessible to the locals [14].

Unsanitary conditions have become the norm. Floors remain unwashed, because hospitals lack cleaning supplies. Cockroach and mice infestations are common. Bedding and clothing are not offered by the hospitals and must therefore be provided by the patients’ families. “Poor sanitation is extended to medical instruments by doctors and nurses; these are not properly sterilized and frequently remain dirty with the remains of tissue and blood after their use” [14]. Syringes as well as disposable gloves are used and reused without any sterilization [14]. Doctors lack sphygmomanometers to measure blood pressure, abundant amounts of disposable gloves, sanitary water for diluting injections, and other basic items that one would expect to find in medical facilities [14]. Electricity is scarce and blackouts are common; in a case of an emergency, a patient might be needlessly left to die [8].

Because Castro took such pride in the medical infrastructure before it fell apart, the state that it is in at the moment and the state of people’s health during the eye disease epidemic were personal embarrassments to Cuba’s leader. The epidemic so harshly struck the country that it “prompted members of the scientific and medical communities to plead for an end to the United States’ economic embargo against Cuba” [15]. The U.S. embargo of Cuba has caused shortages of food, medicine and medical supplies to Cuba’s eleven million people. The embargo is a decadent policy that uses hunger and diseases as political weapons. “Although curtailments of individual liberties and privacy by the Cuban government may seem as an abridgement of personal freedom, we . . . have a moral duty to protest an embargo which engenders human suffering in Cuba to achieve political objectives” [5]. Food, medicine, and water purification materials should be excluded from all sanctions. There needs to be an increase in the number of neutral agencies like the Red Cross that can oversee health effects of bans. Very few other embargoes have restricted medical commerce that deny the availability of prominent medicines to citizens. Such embargoes violate international charters, including the United Nations charter, the charter of the Organization of American States, and the articles of the Geneva Convention establishing acceptable treatment of civilians during wartime [4].

Because economic punishments, like the U.S. embargo on Cuba, cut off food and medical resources, their harshest consequences are felt by the civilian population—least at fault and most vulnerable. Illnesses and diseases that are treated with the most basic medicines and procedures in other countries with abundant medical resources are impossible tasks to manage in Cuba. “In August of 1999, the U.S. Senate voted seventy to twenty-eight in favor of eliminating unilateral export bans in an amendment to next year’s agricultural appropriations bill” [13]. This would have successfully terminated the embargo. Conversely, the U.S. House of Representatives abrogated this amendment in a House-Senate closed committee meeting [13].