Poverty and Parasites in the U.S Border Regions: Poverty Bridges Parasitic Disease into the Rio Grande Valley (RGV)

Introduction: Poverty Borne Parasitic Diseases

The United States of America ranks among the most prosperous countries in the world and the mortality rate of parasitic diseases has immensely reduced over the twentieth century. Nonetheless, a high prevalence of parasitic induced diseases, referred to as the neglected infections of poverty, remain in divergent areas of the United States where poverty is common. Poverty in the United States is focally distributed into a few defined geographic areas of which the border regions of the United States and Mexico are most relevant to Americans living in the Rio Grande Valley (RGV). The Rio Grande Valley, approximately, allocates an estimated population of 1, 100, 000 people, the majority of which are Hispanic, and many of these border communities possess substandard and insubstantial housing conditions which enhance the exposure, infection and transmission of parasitic diseases including but not limited to Cysticercosis, Chagas Disease, Dengue and Leishmaniasis among others which prominently affects the Hispanic population in the area. Roughly, 20.6% of the Hispanic population live in poverty and, hence, are detrimentally exposed to acquiring parasitic diseases. Therefore, serious precautions must and ought to be enforced to prevent the contamination of parasites and their successful reproduction such as treating contaminated patients, administering active surveillance, acquiring vector control, adopting hygienic approaches to improve housing conditions and further research and development of preventive vaccines to improve the treatment of Cysticercosis, Chagas Disease, Dengue fever and Leishmaniasis (Hotez).

Cysticercosis

Cysticercosis is among one of the most prevalent parasitic diseases in the United States and Mexico bordering regions with an estimate of in between 41,400 and 169, 000 cases. Cysticercosis is acquired by ingesting the eggs of Taenia solium, the pork tape worm, which are defecated near the households and families exposed areas. Children are often common host for this parasite because of their lack of hygiene and their young tendency to place their hands in their mouths which facilitates the transmission of Taenia solium eggs into humans. Poor living conditions and a lack of hygiene drastically increase the transmission rate of Taenia solium. Cysticercosis, similarly to other fecal–oral-transmitted diseases, can be spread either directly from person to person or through contaminated food. Persons infected with the adult Taenia solium tapeworms are typically asymptomatic and may not be aware of their infection or of the potential risk to themselves and the transmission to others. If hygiene is poor, transmission of eggs may occur more readily, particularly within households where repeated opportunities for exposure exist among family members. In addition, Cysticercosis can also be acquired by ingesting raw or undercooked pork. Thereafter, Taenia solium is responsible for serious illness and even death in certain cases among which neurocysticercosis, when the larvae invades the central nervous system, yields the most serious pathology. Currently, this condition is the leading cause of seizures, epilepsy, and other neurological disorders among the United States-Mexico borders and presumably accounts for nearly 10% of seizures presenting to the emergency rooms in border cities. Hence, it should be seriously considered to establish cysticercosis as a nationally notified disease and implement public health response to cases of cysticercosis. Such a response should include establishing surveillance, screening, for the disease and required reporting of cases. Upon the discovery of a cysticercosis case, follow-up and testing of household members and other close contacts should be conducted to identify tapeworm carriers, treat them and remove their infection as sources of continuing future transmission (Eberhard).

Vector Transmitted Diseases: Chagas Disease, Dengue Fever and Leishmaniasis

            Furthermore, a vast divergent number of vector borne parasitic diseases such as Chagas disease, Dengue fever and Leishmaniasis are enhanced by poor living conditions like housing without plumbing, air conditioning, or window screens. A vector refers to any agent that acts as a carrier or transporter for an infection. Unfortunately, more than 30, 000 households in the border as well as a vast number of mobile homes have been estimated to qualify as potential refuges for vector and host interaction and the consequent parasitic reproduction, according to studies conducted by A.K, Glasmeier.

            Chagas’ disease, for example, is an infection caused by the presence of Trypanosoma cruzi transmitted to humans by the feces of Reduviidae, also known as “kissing bugs,” when they feed on the blood of humans. Kissing bugs serve as vector, transporting Trypanosoma cruzi from one host to the next as it feeds on blood. On the other hand, transmission of the infection also occurs via vertical transmission from the mothers’ placenta to her offspring, via blood transfusion, organ transplants, and ingestion of triatomine-contaminated food or drink in the most part. Chagas’ disease is characterized by having two stages, an acute stage and a chronic stage. During the acute phase of infection, the multiple waves of trypomastigotes invade host cells and damage them, thus, resulting in fevers, neurological disorders as well as heart failure

            On the contrary, the chronic phase of infection is characterized by a slower onset of symptoms although it might affect intestinal muscles and heart muscles, eventually leading to heart failure and death. Substandard housing in the bordering regions of the United States like the Rio Grande Valley (RGV) bridges vectors and, in this case, Trypanosoma cruzi to invade an altogether prosperous country like the USA. The implementation of vector control and eradication of vector via insecticide can eventually lead to the eradication of the infection. However, Trypanosoma cruzi is able to utilize other mammals as reservoir host, a host that serves as a source of infection and potential re-infection of humans and as a means of sustaining a parasite when it is not infecting human’s in whom the parasite causes a lower pathology, making the control of Chagas’ disease infinitely more difficult (Southern et al).

In addition, a higher quality in housing positively correlates with a lower rate of infection of the Dengue fever, vectored by mosquitoes. Dengue fever in the United States is not as prevalent as it is in Mexico, for instance, because of the superior dwellings which the Americans inhabit. Nonetheless, a cross- sectional survey in of Brownsville, Texas and Matamoros Tamaulipas, Mexico detected that a 2% of the Brownsville population is recently infected with Dengue compared to a 7.3% of Matamoros’ residents and further provided with evidence to support that, time ago, even a 40% of Brownsville residents suffered of Dengue. Common factors among the infected Brownsville population include a low weekly family income, as well as the lack of air conditioning and inadequate draining system in the streets all of which together contribute to a poor housing environment (Hotez).

            Finally, Leishmaniasis is an infectious disease that is extremely recognized as a concomitant of poverty with high rates of morbidity and mortality in addition to a vast geographical distribution. Poor environmental sanitation, detrimental housing conditions and proximity of domestic animals are imperative factors underlying the cause of the infection. Leishmaniasis can be transmitted by direct contact with domestic animals like cats, zoonosis, and vertically transmitted from mother to offspring which is why pregnant women are told to avoid changing the cat glitter. Leishmaniasis comprises two major diseases, the Cutaneous Leishmaniasis form (CL), which can heal spontaneously but leaves despicable disfiguring scars and the more dangerous visceral Leishmaniasis (VL), which can be fatal if untreated (Alvar, Yactayo and Caryn).

Conclusion: Annihilating Poverty Induced Parasitic Diseases

            Despite of the improvement of living conditions and the consequent decrease of neglected infections of poverty in the United States there still remain areas in the country like the border regions which possess a high prevalence of infection where policy needs to be implemented to limit the transmission, reproduction and to seek the possible eradication of neglected infections of poverty diseases. According to Peter J. Hotez, estimates of a preliminary disease burden of the neglected infections of poverty identifies tens of thousands, or in some cases, perhaps even hundreds of thousands of poor Americans that host these chronic infections, which readily represent some of the greatest health disparities in the United States. Consequently, specific policy recommendations such as active surveillance (including newborn screening) to ensure accurate population-based estimates of the disease burden; as well as epidemiological studies to determine the extent of the transmission of Chagas’ disease and other infections; mass or targeted treatments towards infected individuals or populations; vector control; maintenance of a hygienic living environment; education of the affected population to enhance their opportunities to avoid or limit their level of infection and, lastly, research and development for new control tools including improved diagnostics and accelerated development of a vaccine to prevent or annihilate poverty induced parasitic diseases are a few of the many options available to improve the life of residents of unprivileged areas, in this case residents of the border regions of Mexico and USA.