Prevalence of antibody to Trypanosoma cruzi in pregnant Hispanic women in Houston

Chagas Disease Diagnostic Testing in Two Academic Hospitals in New Orleans, Louisiana: A Call to Action

Chagas disease, caused by the protozoa parasite Trypanosoma cruzi, is an anthropozoonosis that represents a major public health problem in the Americas, affecting 7 million people with at least 65 million at risk. We sought to assess the intensity of disease surveillance based on diagnostic test requests from hospitals in New Orleans, Louisiana. We extracted information from send-out labs at two major tertiary academic hospitals in New Orleans, Louisiana, USA, from 1 January 2018 to 1 December 2020. We found that in these three years there were 27 patients for whom Chagas disease testing was ordered. Most of these patients were male (70%), with a median age of 40 years old, and their most common ethnical background was Hispanic (74%). These findings demonstrate undertesting of this neglected disease in our region. Given the low Chagas disease surveillance, we need to increase awareness, health promotion, and education among healthcare workers.

Recommendations for Screening and Diagnosis of Chagas Disease in the United States

BACKGROUND

Chagas disease affects an estimated 326 000-347 000 people in the United States and is severely underdiagnosed. Lack of awareness and clarity regarding screening and diagnosis is a key barrier. This article provides straightforward recommendations, with the goal of simplifying identification and testing of people at risk for US healthcare providers.

METHODS

A multidisciplinary working group of clinicians and researchers with expertise in Chagas disease agreed on 6 main questions, and developed recommendations based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, after reviewing the relevant literature on Chagas disease in the United States.

RESULTS

Individuals who were born or resided for prolonged time periods in endemic countries of Mexico and Central and South America should be tested for Trypanosoma cruzi infection, and family members of people who test positive should be screened. Women of childbearing age with risk factors and infants born to seropositive mothers deserve special consideration due to the risk of vertical transmission. Diagnostic testing for chronic T. cruzi infection should be conducted using 2 distinct assays.

CONCLUSIONS

Increasing provider-directed screening for T. cruzi infection is key to addressing this neglected public health challenge in the United States.

Trypanosoma cruzi infection in Latin American pregnant women living outside endemic countries and frequency of congenital transmission: a systematic review and meta-analysis

BACKGROUND

Chagas disease, as a consequence of globalization and immigration, is no more restricted to Central and Latin America. Therefore, congenital transmission represents a growing public health concern in non-endemic countries.

METHODS

The aim of this study was to assess the prevalence of Trypanosoma cruzi infection in pregnant Latin American (LA) women living outside endemic countries and the rate of congenital transmission. Data were extracted from studies indexed in PubMed, Scopus, Embase, Lilacs and SciELO databases without language restriction. Two investigators independently collected data on study characteristics, diagnosis, prevalence of infection in pregnant women and congenital infection rate. The data were pooled using a random effects model.

RESULTS

The search identified 1078 articles of which 29 were eligible regarding prevalence of T. cruzi infection among pregnant women and 1795 articles of which 32 were eligible regarding the congenital transmission rate. The estimated pooled prevalence of T. cruzi infection in LA pregnant women was 4.2% [95% confidence interval (CI): 3.0-5.5]. The prevalence of T. cruzi infection in pregnant women from Bolivia was 15.5% (95% CI: 11.7-19.7) and 0.5% (95% CI: 0.2-0.89) for those coming from all other LA countries. The estimated global rate of congenital transmission was 3.5% (95% CI: 2.5-4.5); excluding poor-quality studies, the rate of congenital transmission was 3.8% (95% CI: 2.4-5.1).

CONCLUSIONS

Prevalence of Chagas disease among LA pregnant women living outside endemic countries is high, particularly in Bolivian women. The rate of vertical transmission of T. cruzi infection is similar to the rate reported in South and Central American countries.

Congenital Chagas Disease in the United States: The Effect of Commercially Priced Benznidazole on Costs and Benefits of Maternal Screening

Chagas disease, caused by Trypanosoma cruzi, is transmitted by insect vectors, and through transfusions, transplants, insect feces in food, and mother to child during gestation. An estimated 30% of infected persons will develop lifelong, potentially fatal cardiac or digestive complications. Treatment of infants with benznidazole is highly efficacious in eliminating infection. This work evaluates the costs of maternal screening and infant testing and treatment for Chagas disease in the United States, including the cost of commercially available benznidazole. We compare costs of testing and treatment for mothers and infants with the lifetime societal costs without testing and consequent morbidity and mortality due to lack of treatment or late treatment. We constructed a decision-analytic model, using one tree that shows the combined costs for every possible mother–child pairing. Savings per birth in a targeted screening program are $1,314, and with universal screening, $105 per birth. At current screening costs, universal screening results in $420 million in lifetime savings per birth-year cohort. We found that a congenital Chagas screening program in the United States is cost saving for all rates of congenital transmission greater than 0.001% and all levels of maternal prevalence greater than 0.06% compared with no screening program.

Congenital Chagas Disease in the United States: Cost Savings through Maternal Screening

Chagas disease, caused by Trypanosoma cruzi, is transmitted by insect vectors through transfusions, transplants, insect feces in food, and from mother to child during gestation. Congenital infection could perpetuate Chagas disease indefinitely, even in countries without vector transmission. An estimated 30% of infected persons will develop lifelong, potentially fatal, cardiac or digestive complications. Treatment of infants with benznidazole is highly efficacious in eliminating infection. This work evaluates the costs of maternal screening and infant testing and treatment of Chagas disease in the United States. We constructed a decision-analytic model to find the lower cost option, comparing costs of testing and treatment, as needed, for mothers and infants with the lifetime societal costs without testing and the consequent morbidity and mortality due to lack of treatment or late treatment. We found that maternal screening, infant testing, and treatment of Chagas disease in the United States are cost saving for all rates of congenital transmission greater than 0.001% and all levels of maternal prevalence above 0.06% compared with no screening program. Newly approved diagnostics make universal screening cost saving with maternal prevalence as low as 0.008%. The present value of lifetime societal savings due to screening and treatment is about $634 million saved for every birth year cohort. The benefits of universal screening for T. cruzi as part of routine prenatal testing far outweigh the program costs for all U.S. births.

Interdisciplinary approach at the primary healthcare level for Bolivian immigrants with Chagas disease in the city of São Paulo

Background/Methods

In a pioneering cross-sectional study among Bolivian immigrants in the city of São Paulo, Brazil, the epidemiological profile, clinical manifestations and morbidity of Chagas disease were described. The feasibility of the management of Chagas disease at primary healthcare clinics using a biomedical and psychosocial interdisciplinary approach was also tested. Previously, a Trypanosoma cruzi (T. cruzi) infection rate of 4.4% among 633 immigrants was reported. The samples were screened using two commercial enzyme-linked immunoassay (ELISA) tests generated with epimastigote antigens, and those with discrepant or seropositive results were analyzed by confirmatory tests: indirect immunofluorescence (IFI), TESA-blot and a commercial recombinant ELISA. PCR and blood cultures were performed in seropositive patients.

Results

The majority of the 28 seropositive patients were women, of whom 88.89% were of child-bearing age. The predominant clinical forms of Chagas disease were the indeterminate and atypical cardiac forms. Less than 50% received the recommended antiparasitic treatment of benznidazole. An interdisciplinary team was centered on primary healthcare physicians who applied guidelines for the management of patients. Infectologists, cardiologists, pediatricians and other specialists acted as reference professionals. Confirmatory serology and molecular biology tests, as well as echocardiography, Holter and other tests, were performed for the assessment of affected organs in secondary healthcare centers. The published high performance of two commercial ELISA tests was not confirmed.

Conclusion

An interdisciplinary approach including antiparasitic treatment is feasible at the primary healthcare level for the management of Chagas disease in Bolivian immigrants. The itinerant feature of immigration was associated with a lack of adherence to antiparasitic treatment and was considered a main challenge for the clinical management of this population. This approach is recommended for management of the infected population in endemic and nonendemic areas, although different strategies are needed depending on the severity of the disease and the structure of the healthcare system.

Chagas disease affects approximately 6 million Latin American people. It is considered a neglected tropical disease since it mainly affects vulnerable, poverty-stricken people. Public health policies and investments in research on new treatment and control instruments have not been prioritized. In fact, disease urbanization occurred in Latin America in the 80s, and an estimated 15 million people moved from disease-endemic areas to nonendemic areas. Estimations have indicated that 2.9% of immigrants were infected by T. cruzi in 15 European countries, and more than 300,000 infected immigrants resided in the USA. In São Paulo, the estimated number of Bolivian immigrants exceeds 300,000. This study revealed the presence of mild clinical manifestations in predominantly young infected individuals, including reproductive-age women. For the first time, the feasibility of managing chronic Chagas disease at primary healthcare level centers with a biomedical and psychosocial interdisciplinary approach has been reported in the National Public Health System of Brazil. Additionally, the utilized commercial tests did not confirm the previously expected performance for diagnosis of infection. Finally, the itinerant characteristics of the Bolivian immigrant population was reported as a main factor underlying the lack of adherence to antiparasitic treatment and a main challenge for complete clinical management.

Control and management of congenital Chagas disease in Europe and other non-endemic countries: current policies and practices

OBJECTIVES

Identifying pregnant women infected with Trypanosoma cruzi is one of the major challenges for preventing and controlling Chagas disease (CD) in non-endemic countries. The aim of this paper was to perform a policy evaluation of the current practices of congenital Chagas disease (CCD) control in non-endemic countries and to propose specific targets for enhanced interventions to tackle this emerging health problem outside the endemic areas of Latin America.

METHODS

We conducted a mixed method review of CCD policy strategies by searching the literature in the PubMed, Google Scholar and the World Health Organization (WHO) databases using the key terms 'CCD', 'paediatric Chagas disease' and 'non-endemic countries'; as free text and combined as one phrase to increase the search sensitivity. Reviews, recommendations, guidelines and control/surveillance programme reports were included.

RESULTS

Of 427 CCD papers identified in non-endemic countries, 44 matched the inclusion. Although local programmes were launched in different countries with large numbers of Latin American immigrants, there were considerable disparities in terms of the programmes' distribution, delivery, integration and appropriated CCD control strategies. Moreover, Catalonia, Spain is the only region/country with an established systematic monitoring of CCD in pregnant women from Latin American countries.

CONCLUSIONS

Given the worldwide dissemination of CD, the nature of its vertical transmission, and the gaps of the current strategies in non-endemic countries, there is an urgent need to standardise, expand and reinforce the control measures against CCD transmission.

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

Chagas disease (Trypanosoma cruzi infection) has recently been identified as an important neglected tropical disease in the United States. Anecdotally referred to as a "silent killer," it leads to the development of potentially fatal cardiac disease in approximately 30% of those infected. In an attempt to better understand the potential of Chagas disease as a significant underlying cause of morbidity in Texas, we performed a historical literature review to assess disease burden. Human reports of triatomine bites and disease exposure were found to be prevalent in Texas. Despite current beliefs that Chagas disease is a recently emerging disease, we report historical references dating as far back as 1935. Both imported cases and autochthonous transmission contribute to the historical disease burden in Texas. We end by discussing the current knowledge gaps, and recommend priorities for advancing further epidemiologic studies and their policy implications.

Mother-to-Child Transmission of Chagas Disease in El Salvador

To estimate the incidence (any mother to child) and rate (from seropositive mother to child) of mother-to-child transmission of Trypanosoma cruzi, a serological census was conducted, targeting pregnant women and infants born to seropositive mothers, in four municipalities of El Salvador. Of 943 pregnant women, 36 (3.8%) were seropositive for T. cruzi. Of 36, 32 proceeded to serological tests of their infants when they became 6-8 months of age. Six infants seropositive at the age of 6-8 months further proceeded to second-stage serological test at the age of 9-16 months. As the result, one infant was congenitally infected. Thus, serological tests at the age of 6-8 months produced five false positives. To ensure earlier effective medication only for true positives, identification of seropositive infants at the age of 9-16 months is crucial. Incidence and rate of mother-to-child transmission were 0.14 (per 100 person-years) and 4.0%, respectively. Estimated number of children infected through mother-to-child transmission in El Salvador (170 per year) was much higher than that of human immunodeficiency virus (HIV; seven per year). It is recommended that serological testing for T. cruzi be integrated into those for HIV and syphilis as part of antenatal care package.

Evidence of autochthonous Chagas disease in southeastern Texas

Autochthonous transmission of Trypanosoma cruzi in the United States is rarely reported. Here, we describe five newly identified patients with autochthonously acquired infections from a small pilot study of positive blood donors in southeast Texas. Case-patients 1-4 were possibly infected near their residences, which were all in the same region ∼100 miles west of Houston. Case-patient 5 was a young male with considerable exposure from routine outdoor and camping activities associated with a youth civic organization. Only one of the five autochthonous case-patients received anti-parasitic treatment. Our findings suggest an unrecognized risk of human vector-borne transmission in southeast Texas. Education of physicians and public health officials is crucial for identifying the true disease burden and source of infection in Texas.

Neglected parasitic infections in the United States: Chagas disease

Chagas disease, which is caused by the protozoan parasite Trypanosoma cruzi, can lead to severe cardiac and gastrointestinal disease. Most persons acquire this infection through contact with vector bugs carrying T. cruzi in endemic areas of Latin America. Infection can also be acquired by congenital, transfusion, transplantation, and foodborne transmission. Although an estimated 300,000 persons with Chagas disease live in the United States, little is known about the burden of chagasic heart disease. It is not known how often congenital or vector-borne transmission of T. cruzi occurs in the United States, although it is known that infected mothers and infected vector bugs are found in this country. Better diagnostic tests and treatment drugs are needed to improve patient care, and research is needed to define transmission risks and develop strategies to prevent new infections and reduce the burden of disease.

Impact of chagas disease in bolivian immigrants living in europe and the risk of stigmatization

Background. The prevalence of Chagas disease in endemic countries varies with the kind of vector involved and the socioeconomic conditions of the population of origin. Due to recent immigration it is an emerging public health problem in Europe, especially in those countries which receive immigrant populations with a high prevalence of carriers. The study reviews the impact of the disease on Bolivian immigrants living in Europe, the preventive measures and regulations applied in European countries, and their repercussion on possible stigmatization of certain population groups. Methods. The Bolivian immigrant population resident in 2012 was estimated and the affected population in different European countries was calculated with data on carrier prevalence that were recently published. The preventive measures and regulations available in Europe were also reviewed. MEDLINE-PubMed, GoPubMed, and Embase were consulted for the literature review. Results. The Bolivian immigrant population has the highest prevalence of Chagas carriers (6.7%–25%) compared to the overall Latin American population (1.3%–2.4%). Only in Spain, France, Belgium, UK, Portugal, Italy, Switzerland, The Netherlands, and Germany, preventive measures are applied to this population. The established regulations are insufficient and completely different criteria are applied in the different countries and this could reflect a certain degree of stigmatization.

Globalization of Chagas Disease: A Growing Concern in Nonendemic Countries

Chagas disease, caused by the parasite Trypanosoma cruzi, is a major cause of morbidity and mortality in Central and South America. Initial infection and ensuing chronic infection often go undetected in the human host. High seroprevalence of T. cruzi infection is well documented in endemic areas. Designated as “a neglected tropical disease” by the World Health Organization, rural economically disadvantaged and marginalized populations in endemic countries traditionally have the highest rates of infection. As economic hardship, political instability, and the search for opportunity spur migration of infected humans from endemic to non-endemic areas of the world, blood bank data have documented rising seroprevalence of T. cruzi in traditionally nonendemic areas. In these areas, T. cruzi is transmitted through blood transfusion, organ transplantation, and maternal-fetal mechanisms. Increasing awareness of large numbers of infected immigrants in nonendemic countries, and the medical care they require, has focused attention on the need for strategic programs for screening affected populations, education of healthcare providers, and provision of necessary medical services for those infected. Physicians in nonendemic countries should be able to recognize signs and symptoms of acute and chronic Chagas disease as migration and globalization increase the burden of disease in non-endemic areas.

Chagas disease in Latin American pregnant immigrants: experience in a non-endemic country

PURPOSE

Chagas disease is a systemic chronic parasitic infection by Trypanosoma cruzi endemic in Latin America. Migration of women of childbearing age from Latin America to developed countries may spread the disease to non-endemic areas through vertical transmission.

METHODS

Prospective study of seroprevalence of T. cruzi infection in immigrant Latin American pregnant women during a 5-year period (from 2006 to 2010) in Spain.

RESULTS

Seven out of 545 participants were seropositive for T. cruzi [prevalence 1.28%, 95% confidence interval (CI) 0.06-2.56]. Four (57%) were from Bolivia and three (43.%) from Paraguay. The seroprevalence in pregnant women from Bolivia was 10.26% (95% CI 4.06-23.58) and in participants from Paraguay was 6.52% (95% CI 2.24-17.5). No congenital transmission occurred.

CONCLUSIONS

Seroprevalence of T. cruzi infection in Latin American pregnant women coming from Bolivia and Paraguay is high. Those women should be screened for T. cruzi to control mother-to-child transmission in non-endemic areas.

Economic evaluation of Chagas disease screening of pregnant Latin American women and of their infants in a non endemic area

Migration is a channel through which Chagas disease is imported, and vertical transmission is a channel through which the disease is spread in non-endemic countries. This study presents the economic evaluation of Chagas disease screening in pregnant women from Latin America and in their newborns in a non endemic area such as Spain. The economic impact of Chagas disease screening is tested through two decision models, one for the newborn and one for the mother, against the alternative hypothesis of no screening for either the newborn or the mother. Results show that the option "no test" is dominated by the option "test". The cost effectiveness ratio in the "newborn model" was 22€/QALYs gained in the case of screening and 125€/QALYs gained in the case of no screening. The cost effectiveness ratio in the "mother model" was 96€/QALYs gained in the case of screening and 1675€/QALYs gained in the case of no screening. Probabilistic sensitivity analysis highlighted the reduction of uncertainty in the screening option. Threshold analysis assessed that even with a drop in Chagas prevalence from 3.4% to 0.9%, a drop in the probability of vertical transmission from 7.3% to 2.24% and with an increase of screening costs up to €37.5, "test" option would still be preferred to "no test". The current study proved Chagas screening of all Latin American women giving birth in Spain and of their infants to be the best strategy compared to the non-screening option and provides useful information for health policy makers in their decision making process.

Survey of obstetrician-gynecologists in the United States about Chagas disease

Chagas disease affects an estimated 300,000 people in the United States, and as many as 300 congenital infections are estimated to occur annually. The level of knowledge about Chagas disease among obstetricians-gynecologists in the United States has not been assessed. The American College of Obstetricians and Gynecologists surveyed a representative sample of 1,000 members about Chagas disease. Among 421 respondents, 68.2% (95% confidence interval [CI] = 63.5-72.6) described their knowledge level about Chagas disease as "very limited." Only 8.8% (95% CI = 6.2-12.0) knew the risk of congenital infection, and 7.4% (95% CI = 5.1-10.4) were aware that both acute and chronic maternal infections can lead to congenital transmission. The majority of respondents (77.9%; 95% CI = 73.5-81.9) reported "never" considering a diagnosis of Chagas disease among their patients from endemic countries. Most of those who did consider the diagnosis did so "rarely." Knowledge of Chagas disease among obstetricians-gynecologists in the United States is limited. Greater awareness may help to detect treatable congenital Chagas cases.

Chagas disease: a Latin American health problem becoming a world health problem

Political repression and/or economic stagnation stimulated the flow of migration from the 17 Latin American countries endemic for Chagas disease to developed countries. Because of this migration, Chagas disease, an autochthonous disease of the Continental Western Hemisphere is becoming a global health problem. In 2006, 3.8% of the 80,522 immigrants from those 17 countries to Australia were likely infected with Trypanosoma cruzi. In Canada in 2006, 3.5% of the 156,960 immigrants from Latin America whose country of origin was identified were estimated to have been infected. In Japan in 2007, there were 80,912 immigrants from Brazil, 15,281 from Peru, and 19,413 from other South American countries whose country of origin was not identified, a portion of whom may have been also infected. In 15 countries of Europe in 2005, excluding Spain, 2.9% of the 483,074 legal Latin American immigrants were estimated to be infected with T. cruzi. By 2008, Spain had received 1,678,711 immigrants from Latin American endemic countries; of these, 5.2% were potentially infected with T. cruzi and 17,390 may develop Chagas disease. Further, it was estimated that 24-92 newborns delivered by South American T. cruzi infected mothers in Spain may have been congenitally infected with T. cruzi in 2007. In the USA we estimated that 1.9% of approximately 13 million Latin American immigrants in 2000, and 2% of 17 million in 2007, were potentially infected with T. cruzi. Of these, 49,157 and 65,133 in 2000 and 2007 respectively, may have or may develop symptoms and signs of chronic Chagas disease. Governments should implement policies to prevent donations of blood and organs from T. cruzi infected donors. In addition, an infrastructure that assures detection and treatment of acute and chronic cases as well as congenital infection should be developed.

Chagas disease in Spain, the United States and other non-endemic countries

Due to recent trends in migration, there are millions of people from Chagas disease-endemic countries now living in North America, Europe, Australia and Japan, including thousands of people with Trypanosoma cruzi infection. Most infected individuals are not aware of their status. Congenital, transfusion- and/or transplant-associated transmission has been documented in the United States, Spain, Canada and Switzerland; most instances likely go undetected. High priorities include the implementation of appropriate screening, evaluation and clinical management, and better assessment of the true burden associated with this disease.

The baboon model (Papio hamadryas) of fetal loss: maternal weight, age, reproductive history and pregnancy outcome

BACKGROUND

Several risk factors are associated with the incidence of human stillbirths. The prevention of stillbirths in women is a pressing clinical problem.

METHODS

We reviewed 402 pathology records of fetal loss occurring in a large baboon (Papio spp.) colony during a 15-year period. Clinical histories of 565 female baboons with one or more fetal losses during a 20-year period were analyzed for weight, age, and reproductive history.

RESULTS

Fetal loss was most common at term (35.57%) and preterm (28.61%) and less common in the first half of gestation (11.20%) and post-term (5.22%). Greater maternal weight, older age, history of stillbirth and higher parity were independent predictors for stillbirth. An exponential increase in the incidence of fetal loss was observed beginning at age 14 years in baboons.

CONCLUSIONS

Fetal loss and maternal risk factors associated with stillbirths in baboons were similar to those documented in women.

Emerging and zoonotic infections in women

Emerging infections, many zoonotic, are caused by a variety of pathogens with global distribution. Previously rare pathogens have emerged; global travel facilitates their rapid spread. Human encroachment on remote areas has brought contact with zoonotic diseases never before characterized. Although systematic study of rare outbreaks can be challenging, knowledge of emerging pathogens and their effects on women is accumulating. This article discusses effects of lymphocytic choriomeningitis virus, West Nile virus, severe acute respiratory syndrome coronavirus, avian influenza A virus, viral hemorrhagic fevers, spirochetal illnesses, and Chagas' disease. The potential impact of candidate bioterror agents and issues of prophylaxis and therapy are discussed.

Natural Chagas disease in four baboons

BACKGROUND

Chagas disease is common in Central and South America and the southern United States. The causative agent is Trypanosoma cruzi (order Kinetoplastida, family Trypanosomatidae), a kinetoplastid protozoan parasite of humans and other vertebrates. It is a serious public health issue and the leading cause of heart disease and cardiovascular death in Central and South America. In 1984, a colony baboon was discovered to be infected with T. cruzi.

METHODS

As the initial diagnosis was made by microscopic observation of the amastigote forms of T. cruzi in myocardial fibers, T. cruzi amastigotes have been identified in three additional baboons.

RESULTS

The primary findings were similar in all four baboons and were congestive heart failure with edema of dependent areas, hydrothorax, hydropericardium, and multifocal to diffuse lymphoplasmacytic myocarditis.

CONCLUSIONS

A baboon animal model of Chagas disease could contribute significantly to the development of therapies for the disease in humans.

Trypanosoma cruzi in non-human primates with a history of stillbirths: a retrospective study (Papio hamadryas spp.) and case report (Macaca fascicularis)

BACKGROUND

Congenital transmission of Trypanosoma cruzi has been described in humans and experimental work has been conducted with mice, but not with non-human primates (NHPs).

METHODS

We conducted a retrospective study of female baboons (Papio hamadryas spp.) naturally seropositive or seronegative for T. cruzi with history of fetal loss, and we report a stillbirth in a cynomolgus macaque (Macaca fascicularis) with placental T. cruzi amastigotes.

RESULTS

There were no differences in menstrual cycle parameters and the number of fetal losses between seropositive and seronegative baboons with history of fetal loss. The amount of parasite DNA detected using quantitative polymerase chain reaction (Q-PCR) in M. fascicularis placenta was within the range detected in infected baboon tissues.

CONCLUSIONS

There is no evidence that chronic maternal T. cruzi infection causes fetal loss in baboons. Q-PCR is a useful diagnostic tool to study archived NHP placentas.

Epidemiology of Chagas disease in non-endemic countries: the role of international migration

Human infection with the protozoa Trypanosoma cruzi extends through North, Central, and South America, affecting 21 countries. Most human infections in the Western Hemisphere occur through contact with infected bloodsucking insects of the triatomine species. As T. cruzi can be detected in the blood of untreated infected individuals, decades after infection took place; the infection can be also transmitted through blood transfusion and organ transplant, which is considered the second most common mode of transmission for T. cruzi. The third mode of transmission is congenital infection. Economic hardship, political problems, or both, have spurred migration from Chagas endemic countries to developed countries. The main destination of this immigration is Australia, Canada, Spain, and the United States. In fact, human infection through blood or organ transplantation, as well as confirmed or potential cases of congenital infections has been described in Spain and in the United States. Estimates reported here indicates that in Australia in 2005-2006, 1067 of the 65,255 Latin American immigrants (16 per 1000) may be infected with T. cruzi, and in Canada, in 2001, 1218 of the 131,135 immigrants (9 per 1000) whose country of origin was identified may have been also infected. In Spain, a magnet for Latin American immigrants since the 2000, 6141 of 38,777 to 339,954 [corrected] legal immigrants in 2003 (25 per 1000), could be infected. In the United States, 56,028 to 357,205 of the 7,20 million, legal immigrants (8 to 50 per 1000), depending on the scenario, from the period 1981-2005 may be infected with T. cruzi. On the other hand, 33,193 to 336,097 of the estimated 5,6 million undocumented immigrants in 2000 (6 to 59 per 1000) could be infected. Non endemic countries receiving immigrants from the endemic ones should develop policies to protect organ recipients from T. cruzi infection, prevent tainting the blood supply with T. cruzi, and implement secondary prevention of congenital Chagas disease.

Chagas disease in Texas: Recognizing the significance and implications of evidence in the literature

Chagas disease is endemic and is recognized as a major health problem in many Latin American countries. Despite the parallels between socio-economic and environmental conditions in Texas and much of Latin America, Chagas disease is not a notifiable human disease in Texas. Based on extensive review of related literature, this paper seeks to recognize the evidence that Chagas Disease is endemic to Texas but the epidemiological, parasitological and entomological patterns of Chagas disease in Texas are both different from and parallel to other endemic regions. We find that with a growing immigrant human reservoir, the epidemiological differences may be reduced and result in increasing incidence of the disease. Chagas disease should be recognized as an emerging disease among both immigrant and indigenous populations. Without proper actions, Chagas disease will place increasing burden on the health care system. Current medical treatments consist of chemotherapies that carry the risk of serious side effects; curing the potentially fatal disease remains equivocal. Therefore, as shown in South America, prevention is paramount and can be successfully achieved through intervention and education. We conclude that biogeographical research is needed to (1) distinguish the dynamic evolution of the agent-vector-host system, (2) document locations with greater risk and identify mechanisms responsible for observed changes in risk, and (3) assist in developing a model for Triatomid vector-borne disease in states like Texas where the disease is both endemic and may be carried by a sizeable immigrant population. Tracking of Chagas disease and planning for appropriate health care services would also be aided by including Chagas disease on the list of reportable diseases for humans.

Mother-to-Child Transmission of Chagas’ Disease in North America: Why Don’t We Do More?

OBJECTIVES

Mothers with Chagas' disease can transmit Trypanosoma cruzi to their fetuses, who often become carriers of the infection and are then at risk of developing severe cardiac disease later in the course of their lives. If identified early enough after birth, the infected newborns can be treated and cured. Our objective was to review the data available in Canada, Mexico, and the United States and to discuss the need for prevention programs.

METHODS

We reviewed the literature and estimated the number of seropositive mothers and newborns infected by T. cruzi.

RESULTS

We estimate that about 40,000 pregnant women and 2,000 newborns are likely to be infected by T. cruzi in North America. We have not identified any ongoing prevention programs.

CONCLUSIONS

Mother-to-child transmission of T. cruzi has all the characteristics required to be a public health priority, as it is relatively frequent, severe, identifiable, and treatable. In reality, it is a neglected disease and a missed opportunity. It is urgent to better understand the epidemiology of mother-to-child transmission of T. cruzi in North America and to develop effective prevention programs.