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Don't Touch? Don't Kiss? Do Tell!


Nicole Brooks
nibrooks@utmb.edu

Sultana Peffley
skpeffle@utmb.edu

Marilyn Galindo, MD
mbgalind@utmb.edu

Vincent Valentine, MD
University of Texas Medical Branch
Galveston, TX, USA
vgvalent@utmb.edu



On September 30, 2014, the CDC confirmed the first laboratory-confirmed case of Ebola in a Liberian man visiting Dallas, Texas, United States. He died one week later; cause of death: Ebola. At the same time, a healthcare worker involved in his care tested positive for the virus. Five days later, a second health care worker involved in the index patient's care also tested positive for Ebola. A week after the 3rd case, a 4th case of Ebola, in a physician working with Doctors Without Borders, was reported by the New York City Department of Health and Mental Hygiene [1]. The United States' government's reactions ranged from cooperation with the CDC's recommendations for infection prevention to more extreme reactions including orders to institute mandatory 21-day at home quarantine for all healthcare workers returning from endemic areas who had unprotected contact with a patient diagnosed with Ebola. Further, government agencies also enacted our legal institutions to block the ashes of Ebola victims entering specific states. We may never know whether these actions were beneficial or detrimental, but we do know this: all 3 cases of diagnosed Ebola following the index patient have since recovered and all definite exposure contacts and possible exposure contacts have completed a 21-day active surveillance period without a single new case reported. The United States has officially, and successfully, contained its Ebola virus outbreak, and the death of one Liberian man has effectively revealed the way Americans react to emerging biological threats from abroad.

Many kept up with the various Ebola virus news updates and had plenty of discussions with co-workers, family, and friends regarding potential plans if a patient with recent travel history to West Africa were to be encountered. On a similar note, how many conversations have been centered around Chagas disease? An infection arguably just as detrimental as Ebola. Why hasn't the media grasped and sensationalized this insidious infection? How do we counteract America's newfound expertise in regards to news surrounding the Ebola virus, but its relative naïveté in regards to the alarming news surrounding 5 newly identified cases of Chagas disease? No idea. Nonetheless, here's the most recent update on an important biological threat that received little attention during the "Fearbola" panic.

The old news is this: Chagas disease is an infection which manifests as cardiomyopathy and gastrointestinal disease, and is caused by the protozoan parasite Trypanosoma cruzi, spread by the bite of triatomines, or "kissing bugs", which are primarily found in the Americas. Less often, Chagas disease is spread vertically via congenital infection from mother to infant. Recently, 5 cases of Chagas disease were all reported near Houston, Texas - a 240 mile distance from Dallas, where the first Ebola case was confirmed. All 5 Chagas disease cases were confirmed to be autochthonus, or originating in the place where found [2]. Because Chagas disease was previously believed to be a remote disease primarily affecting rural and poor populations of Central and South America (i.e., a disease of immigrants) autochthonus cases of Chagas disease are especially alarming. However, in light of these 5 autochthonus cases found in Texas, Chagas disease must now be considered when a patient native to the southern United States presents with cardiac conduction system abnormalities, apical aneurysm in the left ventricle, or progressive dilated cardiomyopathy with congestive heart failure [3].

In news that should have made headlines, Melissa N. Garcia and researchers from Baylor College of Medicine have published data collected between 2008 and 2012 which supports an estimate of 1 in 6,500 Texan blood donors tested positive for T. cruzi [4]. Required screening for the Chagas parasite began in 2007 and the CDC estimated in 2012 that 1 in 354,000 nationwide blood donations test positive for T.cruzi [5]. The implication of these findings is that the United States is currently unprepared to address the rising incidence of T. cruzi infections, as well as rarer forms of transmission of T. cruzi via blood transfusions, organ transplantations and also vertical transmission. The acute infection of Chagas disease is primarily clinically silent, with rare symptomatic manifestations of fever, malaise and chagomas. For 8 to 12 weeks, circulating trypomastigotes are detectable by microscopy of fresh blood or buffy coat smears [6]. If undetected in the acute phase, the chronic phase of Chagas disease is characterized by undetectable circulating trypomastigotes; however, infected persons are still able to transmit trypomastigotes via blood components, organ donation and congenitally.

Thus far, the odds of transmission are relatively low for recipients of liver and kidney transplants, between 13-22%, while the risk of transmission for heart transplants is 75-100% [7]. However, there have been few studies examining blood product and organ donation transmissions. With increasing autochthonous cases, we may see a rise in these numbers in the United States. Another consideration is whether or not patients suffering from Chagas cardiomyopathy are candidates for heart transplant, especially with possible immunosuppression induced Chagas disease reactivation. Those undergoing organ transplantation due to manifestations of Chagas disease are monitored for life. In addition, delineation between disease reactivation and acute organ rejection must be prompt.

PLoS Neglected Tropical Diseases termed Chagas disease "The New AIDS of the Americas" [8]. We can't force the media to dramatize the reduviid kissing bug, but we can be our own informants. As health care workers, we have a responsibility to prevent the development of desperation and panic that will lead to a new generation of Buyers Clubs. After all, 'tis the season to be warm and big hearted. ■

Disclosure Statement: The authors have no conflicts of interest to disclose.


References:
1. CDC Ebola Virus article: http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/united-states-imported-case.html
2. Merriam-Webster "Autochthonus": http://www.merriam-webster.com/dictionary/autochthonous
3. Bern, Caryn, et al. Trypanosoma cruzi and Chagas Disease in the United States. Clinical Microbiology Reviews, Oct. 2011, p. 655-681.
4. Garcia MN, et al. Trypanosoma cruzi screening in Texas blood donors, 2008-2012.Epidemiology and Infection. 2014 August 29:1-4.
5. Cantey PT, et al. 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. 2012 September; 52(9): 1922-30.
6. Bern, Caryn, et al. Trypanosoma cruzi and Chagas Disease in the United States. Clinical Microbiology Reviews, Oct. 2011, p. 655-681.
7. Kransdorf EP, Zakowski PC, Kobashigawa JA. Chagas disease in solid organ and heart transplantation. Curr Opin Infect Dis. 2014;27(5):418-24.
8. http://www.nytimes.com/2012/05/29/science/spread-of-chagas-is-called-the-new-aids-of-the-americas.html?_r=0. Accessed November 27, 2014.




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