“Selecting the NTD in Peru:
Engaging stakeholders in the difficult decision of selecting what underserved disease to prioritize”

The COHESION Project aims to address the double burden of disease that face health systems and communities by improving capacities at the national, local and community levels in three countries (Mozambique, Nepal and Peru). To assess the barriers that underserved communities face when accessing Primary Health Care (PHC) each country team selected a Neglected Tropical Disease (NTD) and two Non-communicable Diseases (NCDs) (diabetes and hypertension). These three diseases would be used as “tracer” conditions to understand the challenges of local health systems to effectively manage these diseases at the PHC level.

Why tracers? Because individuals with one or both, NTD or NCD, have the unique scenario of requiring chronic, engaging, meaningful, respectful and effective care. Both of these tracers, NTDs and NCDs, allow us a second chance to get it right, to redefine the user experience with our healthcare system.

In Mozambique, the selected NTD was Schistosomiasis, while the Nepalese team chose Leprosy. In Peru, we had initially selected Chagas but we felt we needed more information about the various NTDs with chronic sequels affecting people in Peru before making a final decision.

After several discussions with experts and internal conversations about the appropriateness of Chagas and other NTDs including Leprosy, Hydatidosis and Neurocysticercosis, we decided on Neurocysticercosis.

In this post, we share the reasons that lead us to this decision.

We first contacted an expert in Leprosy. We learned that it has not been fully eradicated in some regions in Peru, although the national prevalence rate is lower than 1 case x 10 000 inhabitants (Burstein, 2014). Leprosy still affects some small localities of the Amazon regions, where several geographical barriers and a dispersion settlement pattern predominate (Burstein, 2014). Addressing Leprosy is a challenge given the under diagnosis and other problems related with the epidemiological information systems for reporting of new cases.

Chagas disease affects over 8 million people in the Americas and about 190,000 persons with this disease live in Peru (Bayer et al., 2009). After different national and regional efforts in the nineties for the elimination of the Chagas vector (Triatoma infestans), the incidence of this disease was reduced. The main region affected in Peru is Arequipa, in the Southern Andes. As a result of efforts from different public and private institutions the vectorborne transmission of the disease has been significantly reduced and is now located in peri-urban shantytowns near the city of Arequipa as a response of urbanization processes and migration (Delgado et al., 2011). There is still work to do to eradicate Chagas, starting with the approval of a standardized protocol for the management of the disease and intensification of efforts in diagnosing people plus more thorough surveillance activities with special focus in shantytowns (Bayer et al., 2009). One reason that leads us to reconsider Chagas as the selected NTD is that symptoms may take about 20 years to develop and only few persons who have lesions show a recovery after pharmacological treatment. Additionally, the migration of the disease to peri-urban zone would leave us without the opportunity to explore the response of PHC for patients with NTD in rural area and to develop strategies to enhance the user experience with services provided by the PHC.

When exploring Hydatidosis and Cysticercosis, we learned that “controlling the parasitic infection in animals is crucial to reduce the incidence of human disease” (Otero-Abad & Torgerson, 2013). Both diseases are closely related with human behavior, for example with education about the transmission of the diseases and the prevention with hygiene actions. Currently, there is no vector control program for Hydatidosis in Peru. There was an effort for developing a program that included radio programs with educational messages and the empowerment of school teachers as providers of health and sanitary messages. However, control programs and educative activities were discontinued. Moreover, this disease is not notifiable in Peru, which makes it harder to know its current prevalence.

Finally, we looked into Neurocysticercosis (NCC), which is an “infection of the nervous system by the cystic larvae of Taenia solium” (Garcia, Nash, & Del Brutto, 2014) that frequently causes seizures and epilepsy. Worldwide, over 5 million cases of epilepsy are caused by Neurocysticercosis (Nash, Mahanty, & Garcia, 2013). Neurocysticercosis is especially endemic in areas characterized by poor water and sanitation systems and where pigs are not corralling with access to human feces (García, Gonzalez, Evans, & Gilman, 2003). In Peru, Neurocysticercosis affected approximately 35% of persons with active epilepsy, which is a very high rate comparable with Honduras and India. Only one out of every four patients with active epilepsy receive pharmacological treatment, but in sub-therapeutic doses (Moyano et al., 2014). It has been demonstrated that the transmission of Taenia solium was eliminated in 105 of 107 villages in Tumbes (region located in the north of the country) after an “attack phase” during one year that comprises people and pigs, and this result persisted over 1 year (Garcia et al., 2016; Maurice, 2014). However, there are still cases of NCC in the intervened region after several years of the implementation of the control program and there are other endemic regions affected by this disease in Peru.

The aforementioned efforts for the different NTDs and the pending actions for reaching the control of the diseases were the main topics discussed with different experts in the field. We were impressed with their high motivation, solidarity and expertise gained through the years. For example, there are strong research teams for the study of Chagas and Cysticercosis that have made relevant contributions like the risk mapping of the zones to inform surveillance system for Chagas or the massive intervention in persons and pigs from rural villages of northern Peru for blocking transmission of cysticercosis.

All experts agreed that whatever NTD we chose, we would be making a difference because they affect the most vulnerable.

Our decision about the selection of Neurocysticercosis for the purpose of the COHESION project was made considering to prioritize an NTD that generates a chronic condition that requires long-term treatment like epilepsy and affecting the poor of the poorest population in rural area, where PHC response is more relevant as the first point of entry for care. In so doing, by choosing NCC, together with an understanding of other major prevalent NCD conditions like diabetes and hypertension, will provide us with a second chance to get it right, to redefine the user experience within our healthcare system.

Acknowledgments: We thank César Náquira, Ricardo Castillo, Valerie Paz-Soldán, Aldo Lucchetti, Luz María Moyano, Ricardo Gamboa and H. Hugo García for their valuable time and insights about NTDs for the purpose of the COHESION project.

References:

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Burstein, Z. (2014). Critical appraisal about control programs and elimination of leprosy in Peru, and its consequences for Peru and America. Revista Peruana de Medicina Experimental Y Salud Pública, 31(2), 336–342.

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