The Silent Killer: Improving the Understanding of Chagas Disease

The protozoan parasite Trypanosoma cruzi was first described by Carlos Chagas after isolation of the organism from the blood of a Brazilian patient in 1909 (Garcia et al., 2015). An estimated 7.5 to 10 million persons are infected with Chagas disease worldwide (Hotez et al., 2008; Hotez et al., 2014). In the United States, the disease is anecdotally referred to as a “silent killer” with a 30% chance of those infected to develop a potentially fatal cardiac disease. According to Cantey et al. (2012), Chagas disease is emerging as a significant public health concern in the United States. Given the proximity of Texas to Latin America, cases imported from highly endemic areas in Latin America would likely occur in Texas. Recent communication from the Centers for Disease Control and Prevention that the bite of blood-sucking triatomine bugs in the subfamily Triatominae also termed “kissing bugs” that transfers the parasites to humans have now been found in 28 states, including California and Pennsylvania. Garcia et al. (2015) argued that despite the numerous publications related to Chagas disease in the southern US and northern regions of Mexico, very little is known about the disease burden from imported and locally acquired T. cruzi infection.There is concern that Chagas disease might be undiagnosed in the US as a result of documented low physician awareness (Stimpert & Montgomery, 2010). While the zoonotic nature of Chagas’ life cycle implies unfeasible eradication; entomological surveillance is and will remain crucial to containing Chagas disease transmission (Tarleton et al., 2007).

While it is considered safe to breastfeed even if the mother has Chagas disease (Centers for disease control and prevention, 2013); people can also become infected through blood transfusion, congenital transmission (from a pregnant woman to her baby), organ transplantation, accidental laboratory exposure and consumption of uncooked food contaminated with feces from infected bugs. If the mother has cracked nipples or blood in the breast milk, it is warranted to pump and discard the milk until the bleeding resolves and the nipples heal  (Centers for disease control and prevention, 2013). The enduring challenge of household reinfestation by locally native vectors as stated by Abad-Franch et al. (2011), horizontal strategies works better when the community takes on a protagonist role. Encouraging vector notification by residents and other simple forms of participation can substantially enhance the effectiveness of surveillance (Abad-Franch et al., 2011). Therefore, control programs in concert with community-based approaches as a strategic asset from inception that requires a timely, professional response to every notification, benefiting from a strengthened focus on community empowerment. According to Schofield (1978), when bug population density is low, vector detection failures are unavoidable. Decision-making will be dependent upon the accurate estimation of infestation rates (World Health Organization, 2002), and imperfect detection can seriously misguide Chagas disease control management program. Continued attentiveness from governmental and health organizations are warranted, as this disease continue to be a globalized public health issue. Improved diagnostic tools, expanded surveillance and increased research funding will be required in maintaining existing effective public health strategies and in preventing the spread of the disease to new areas and populations (Bonney, 2014). To improve outbreak control, and improve Chagas disease response, it is essential to discuss the gaps in the scientific knowledge of the disease. Moreover,  crucial in improving the morbidity in the state of Texas and neighboring states is the recommendation of the needed steps to enhance the understanding of T. cruzi.

References

Abad-Franch, F., Vega, M. C., Rolón, M. S., Santos, W. S., & de Arias, A. R. (2011). Community participation in Chagas disease vector surveillance: systematic review. PLoS Negl Trop Dis, 5(6), e1207.

Bonney, K. M. (2014). Chagas disease in the 21st century: a public health success or an emerging threat?. Parasite, 21, 11.

Cantey, P. T., Stramer, S. L., Townsend, R. L., Kamel, H., Ofafa, K., Todd, C. W., … & Hall, C. (2012). The United States Trypanosoma cruzi Infection Study: evidence for vector‐borne transmission of the parasite that causes Chagas disease among United States blood donors. Transfusion, 52(9), 1922-1930.

Centers for disease control and prevention. (2013). Parasites-American Trypanosomiasis (also known as Chagas Disease). Retrieved 21 July, 2016, from http://www.cdc.gov/parasites/chagas/gen_info/detailed.html

Garcia, M. N., Woc-Colburn, L., Aguilar, D., Hotez, P. J., & Murray, K. O. (2015). Historical perspectives on the epidemiology of human chagas disease in Texas and recommendations for enhanced understanding of clinical chagas disease in the Southern United States. PLOS Negl Trop Dis, 9(11), e0003981.

Hotez, P. J., Bottazzi, M. E., Franco-Paredes, C., Ault, S. K., & Periago, M. R. (2008). The neglected tropical diseases of Latin America and the Caribbean: a review of disease burden and distribution and a roadmap for control and elimination. PLoS Negl Trop Dis, 2(9), e300.

Hotez, P. J., Alvarado, M., Basáñez, M. G., Bolliger, I., Bourne, R., Boussinesq, M., … & Carabin, H. (2014). The global burden of disease study 2010: interpretation and implications for the neglected tropical diseases. PLoS Negl Trop Dis, 8(7), e2865.

Schofield, C. J. (1978). A comparison of sampling techniques for domestic populations of Triatominae. Transactions of the Royal Society of Tropical Medicine and Hygiene, 72(5), 449-455.

Stimpert, K. K., & Montgomery, S. P. (2010). Physician awareness of Chagas disease, USA. Emerging infectious diseases, 16(5), 871.

Tarleton, R. L., Reithinger, R., Urbina, J. A., Kitron, U., & Gürtler, R. E. (2007). The challenges of Chagas disease—Grim outlook or glimmer of hope?. PLoS Med, 4(12), e332.

World Health Organization. (2002). Control of Chagas disease: second report of the WHO expert committee.