Browsing by Autor "Freddy Tinajeros"

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32. Risk Factors for Vertical Transmission of <i>t. Cruzi</i> infection in an Endemic Setting
(Oxford University Press, 2020) Melissa D. Klein; Freddy Tinajeros; Edith Málaga; Manuela Verástegui; Beth Jessy Condori; Federico Urquizu; Robert H. Gilman; Natalie M. Bowman
Abstract Members of the Chagas Disease Working Group in Peru and Bolivia include Edith Hinojosa, Clariza Chavez, Jean Karla Velarde, Carla Chavarria, Victoria Serrudo, Roberto Araya, Alcides Buitron, Rita Mendieta, Holger Mayta, Maritza Calderon, Holger Mayta and Yagahira Castro. Background Vertical transmission of Trypanosoma cruzi infection accounts for a growing proportion of new cases of Chagas disease. Congenital infection is curable if treated promptly, but the majority of infected infants do not receive timely diagnosis or treatment. Better risk stratification is needed to predict which women are more likely to transmit the infection. Methods This study enrolled women who presented for delivery and their infants at the Percy Boland Women’s Hospital in Santa Cruz, Bolivia. Pregnant women were screened for Chagas disease by rapid test. The infants of seropositive mothers underwent diagnostic testing with microscopy (“micromethod”) and quantitative polymerase chain reaction (qPCR) as newborns and at one- and nine-month follow-up. Mothers completed surveys about demographics and medical history. Results Among 5,828 enrolled women, 1,271 (21.8%) screened positive for Chagas disease. Of the 1,325 infants of seropositive mothers, 113 (8.5%) were diagnosed with congenital Chagas disease by microscopy or qPCR. Cesarean delivery was significantly associated with lower odds of vertical transmission (adjusted OR: 0.63, 95% CI: 0.41–0.98, p=0.040). Congenital infection was more common in twins (adjusted OR: 3.30, 95% CI: 1.97–5.54, p&lt; 0.001) and male infants (adjusted OR: 1.50, 95% CI: 1.01–1.22, p=0.045). Conclusion Our findings suggest that Cesarean delivery may be protective against vertical transmission of T. cruzi, while twins and male infants may have an increased risk. A better understanding of risk stratification for congenital Chagas disease may help improve regional initiatives to reduce disease burden. Disclosures All Authors: No reported disclosures
Abstract 16978: Use of 2-D Speckle Tracking Strain to Predict Onset of Cardiomyopathy in Chagas Disease
(Lippincott Williams & Wilkins, 2018) Monica Miranda Schaeubinger; Sithu Win; Lola Camila Telleria; Freddy Tinajeros; Jorge Flores; Paula P. Carballo-Jimenez; Caryn Bern; Ronald Gustavo Durán Saucedo; Robert H. Gilman; Monica Mukherjee
Introduction: Chagas disease is a major cause of morbidity in Latin America where it affects approximately 8 million people, with highest prevalence in Bolivia. An estimated 20-30% of those infected develop Chagas cardiomyopathy (CC) and clinical heart failure. There is currently a lack of reliable predictors of CC, hindering early identification and treatment of patients at highest risk of progression. Methods: This prospective observational study was conducted at the Hospital San Juan de Dios in Santa Cruz, Bolivia. Between 2016 and 2018, participants with Chagas disease underwent a focused history and physical exam, 12-lead ECG and echocardiogram at baseline and at 1-year follow-up. Participants were assigned cardiac disease severity stages according to ECG findings and systolic function as done by Okamoto et al. Those classified as stage A or B at baseline were selected from the overall cohort, and considered to have developed cardiomyopathy (stage C or D) by structural abnormalities on their follow-up echo. Echocardiograms were analyzed for peak averaged and regional left ventricular global longitudinal systolic strain (GLS) using TomTec Image-Arena software. Baseline GLS was compared between those who progressed and those who did not using two-sample t-tests. Results: Of the 113 participants with stage A or B at baseline, 10 had progressed to stage C or D at follow-up 1 year later. Mean age was similar in the two groups, however those who progressed were more likely to be male (see table). At baseline, mean LVEF was lower and peak GLS was less negative among those who progressed compared to those who did not. These differences were similar at the follow-up visit. Conclusion: Mild abnormalities in GLS identify patients with Chagas disease with a higher risk of developing cardiomyopathy within 1 year. Screening for these changes may provide a non-invasive and cost-effective approach to identify patients who could benefit from timely management.
Amplicon sequencing reveals complex infection in infants congenitally infected with <i>Trypanosoma cruzi</i> and informs the dynamics of parasite transmission
(2022) Jill Hakim; Andreea Waltmann; Freddy Tinajeros; Oksana Kharabora; Edith Málaga; Maritza Calderón; María del Carmen Menduiña; Jeremy Wang; Daniel Rueda; Mirko Zimic
Abstract Congenital transmission of Trypanosoma cruzi , the causative agent of Chagas disease, is an important source of new infections worldwide. The mechanisms of congenital transmission remain poorly understood, but there is evidence that parasite factors could play a role. Investigating changes in parasite strain diversity during transmission could provide insight into the parasite factors that influence the process. Here we use deep amplicon sequencing of a single copy gene in the T. cruzi genome to evaluate the diversity of infection in a collection of clinical blood samples from Chagas positive mothers and their infected infants. We found several infants and mothers infected with more than two parasite haplotypes, indicating infection with multiple parasite strains. Two haplotypes were detected exclusively in infant samples, while one haplotype was never found in infants, suggesting a relationship between the probability of transmission and parasite genotype. Finally, we found an increase in parasite population diversity in children after birth compared to their mothers, suggesting that there is no transmission bottleneck during congenital infection and that multiple parasites breach the placenta in the course of congenital transmission.
Amplicon Sequencing Reveals Complex Infection in Infants Congenitally Infected With <i>Trypanosoma Cruzi</i> and Informs the Dynamics of Parasite Transmission
(Oxford University Press, 2023) Jill Hakim; Andreea Waltmann; Freddy Tinajeros; Oksana Kharabora; Edith Málaga; Maritza Calderón; María del Carmen Menduiña; Jeremy Wang; Daniel Rueda; Mirko Zimic
Congenital transmission of Trypanosoma cruzi is an important source of new Chagas infections worldwide. The mechanisms of congenital transmission remain poorly understood, but there is evidence that parasite factors are involved. Investigating changes in parasite strain diversity during transmission could provide insight into the parasite factors that influence the process. Here we use amplicon sequencing of a single copy T. cruzi gene to evaluate the diversity of infection in clinical samples from Chagas positive mothers and their infected infants. Several infants and mothers were infected with multiple parasite strains, mostly of the same TcV lineage, and parasite strain diversity was higher in infants than mothers. Two parasite haplotypes were detected exclusively in infant samples, while one haplotype was never found in infants. Together, these data suggest multiple parasites initiate a congenital infection and that parasite factors influence the probability of vertical transmission.
Building Public Health Capacity through a Sustainable South–South–North Training Program
(American Society of Tropical Medicine and Hygiene, 2020) Taryn Clark; Manuela Verástegui; Freddy Tinajeros; Maritza Calderón; Rony Colanzi; Robert H. Gilman
Capacity building in public health is an urgent global priority. Recently, there has been an increasing emphasis on South-South and triangular cooperation. We describe our experience with a public health training collaboration between Peru and Bolivia, with Peru providing capacity building and expertise to Bolivia, while receiving supportive funding and training from the United States. This collaboration has led to a groundswell of research on clinically significant diseases, outreach to more than 800 scientists, several dozen publications, and the start of four institutional review boards. South-South and South-South-North collaborations should publish their experiences, and Northern funding organizations should consider funding such collaborations.
Congenital transmission of Chagas disease by vector circulation zone in Bolivia
(Public Library of Science, 2025) Beatriz Amparo Rodríguez Olguín; Freddy Tinajeros; Beth Jessy Condori; Melissa K. Cutshaw
Congenital transmission of Chagas disease remains common through multiple regions of Bolivia, regardless of local vector circulation control, and is associated with markedly higher rates of infant hospitalization after birth.
Contraception and Condom Use Among Bolivian Female Sex Workers: Relationship-Specific Associations Between Disease Prevention and Family Planning Behaviors
(Taylor & Francis, 2013) Eileen A. Yam; Freddy Tinajeros; Rita Revollo; Kara Richmond; Deanna Kerrigan; Sandra G. García
We examined data from a clinic-based survey of 1,222 Bolivian female sex workers (FSWs) to assess whether use of nonbarrier modern contraception is associated with less consistent condom use with clients and noncommercial partners. Women who were using nonbarrier modern contraception were less likely than nonusers to consistently use condoms with noncommercial partners (AOR 0.393, 95% CI 0.203-0.759, p = .005). With clients, this inverse association did not hold. Public health professionals must consider both disease prevention and pregnancy prevention needs in this vulnerable population, and messages should be tailored to encourage dual method use with all partners.
Demonstrating Public Health at Work: A Demonstration Project of Congenital Syphilis Prevention Efforts in Bolivia
(Lippincott Williams & Wilkins, 2006) Sandra G. García; Freddy Tinajeros; Rita Revollo; Eileen A. Yam; Kara Richmond; Claudia Dı́az-Olavarrieta; Daniel Grossman
Based on these findings, by mid-2006, the Bolivian Ministry of Health will offer the ICS tests in rural ANC settings.
Genome Sequences of Chikungunya Virus Isolates from Bolivia
(American Society for Microbiology, 2020) Caio M B França; Roxana Loayza; Yelin Roca; Ana Maria Montaño Arias; Freddy Tinajeros; José R. Loaiza; Anshule Takyar; Robert H. Gilman; Matthew J. Miller
We generated nine coding-complete chikungunya virus genome sequences from blood samples collected during the early 2015 outbreak in Bolivia. Relative to other publicly available chikungunya sequences, the Bolivian samples represent a monophyletic group, suggesting that a single lineage was widely circulating in the country between February and May 2015.
[Health-worker barriers to syphilis screening in pregnant women in Bolivia's Los Andes network].
(National Institutes of Health, 2017) Freddy Tinajeros; Lucila Rey Ares; Vanessa Elías; Ludovic Revéiz; F. Galán Sánchez; Martha Mejía; Rosalinda Hernández; Rita Revollo
Syphilis screening is not being done according to Bolivia's strategy for the elimination of congenital syphilis, and is not done on more than half of pregnant women in prenatal care with perinatal clinical history records. This is not perceived by health professionals and can become a barrier to syphilis screening in pregnant women.
IgG Subclasses and Congenital Transmission of Chagas Disease
(American Society of Tropical Medicine and Hygiene, 2021) Cristian Roca; Edith S. Málaga-Machaca; Manuela Verástegui; Billy Scola; Edward Valencia Ayala; María del Carmen Menduiña; Sassan Noazin; Natalie M. Bowman; Freddy Tinajeros; Robert H. Gilman
The mechanism of vertical transmission of Trypanosoma cruzi is poorly understood. In this study, we evaluated the role of IgG subclasses in the congenital transmission of Chagas disease. We conducted a case-control study in a public maternity hospital in Santa Cruz, Bolivia, enrolling women at delivery. Thirty women who transmitted T. cruzi to their newborns (cases), and 51 women who did not (controls) were randomly selected from 676 total seropositive women. Trypanosoma cruzi-specific IgG1, IgG2, and IgG3 levels were measured by in-house ELISA. The IgG4 levels were unmeasurable as a result of low levels in all participants. Quantitative polymerase chain reaction results and demographic factors were also analyzed. One-unit increases in normalized absorbance ratio of IgG1 or IgG2 levels increased the odds of congenital T. cruzi transmission in Chagas-seropositive women by 2.0 (95% CI: 1.1-3.6) and 2.27 (95% CI: 0.9-5.7), adjusted for age and previous blood transfusion. Odds of congenital transmission were 7.0 times higher in parasitemic mothers (95% CI: 2.3-21.3, P < 0.01) compared with nonparasitemic mothers. We observed that all mothers with IgG1 ≥ 4 were transmitters (sensitivity = 20%, specificity = 100%). Additionally, no mothers with IgG2 < 1.13 were transmitters (sensitivity = 100%, specificity = 21.6%). We demonstrated that IgG subclasses and parasite presence in blood are associated with vertical transmission of T. cruzi and could identify women at increased risk for congenital transmission by measuring IgG subclasses. These measures have potential as objective screening tests to predict the congenital transmission of Chagas.
Improved DNA extraction technique from clot for the diagnosis of Chagas disease
(Public Library of Science, 2019) Holger Mayta; Yomara K. Romero; Alejandra Pando-Caciano; Manuela Verástegui; Freddy Tinajeros; Ricardo Bozo; Josephine Henderson-Frost; Rony Colanzi; Jorge Flores; Richard M. Lerner
The new methodology for DNA extraction from clot samples improves the molecular diagnosis of Chagas disease.
Mass spectrometry-based discovery and diagnostic validation of T. cruzi antigens in the urine of congenitally infected Chagas Disease patients
(Public Library of Science, 2025) Kathryn Cassels; Raghad Almofeez; Jessica Roman; Hannah Steinberg; Ahana Byne; Amanda Haymond; Freddy Tinajeros; María del Carmen Menduiña; Edith Málaga; Manuela Verástegui
Our work suggests that it is possible to detect Trypanosoma cruzi infection directly from a noninvasively collected fluid such as urine. A direct test in urine with this success rate would be well suited for rapid diagnosis in low-resource areas. Further studies to validate this approach are warranted.
P4.42 Kap study and prevalence of hiv and syphilis in hondura´s private freedom persons
(2017) Freddy Tinajeros
<h3>Introduction</h3> According to the STI/HIV/AIDS Department’s has recorded a total of 32 573 cases Accumulated of which 22 737 are cases of Advanced Infection and 9836 are asymptomatic HIV. The only previous study of persons deprived of liberty (PPL) was in 1999, which included three cities in Honduras and 2095 people were recruited, the majority of which were men. The prevalence of syphilis was 1.8%. <h3>Methods</h3> A cross-sectional study, which used systematic random sampling by clusters, each penal centre gave a proportional share of its population. The universe of persons deprived of liberty consisted of 5813 men (3,531 TGUs and 2,282 SPS) and 430 women (346 TGUs and 84 SPS), who make a total of 6159. The protocol was approved by the Biomedical Research Committee of the National Autonomous University of Honduras (CEIB). <h3>Results</h3> Regarding HIV sero-prevalence, 1.9% (95% CI, 0.8–4.2) of HIV-infected men compared to 0.6% (CI 95%, 0.0–3.4) of women, however, men Of SPS 2 in 3.3% (IC 95%, 0.9–8.2) of HIV compared to 1.0% (95% CI, 0.1–3.5) in TGU men, whereas TGU 2 women were 0.8% (95% CI, 0.0–4.5) and women of SPS 0.0% (95% CI, 0.0–8.8), ie no cases were found in the study sample, however this does not mean that there is no HIV in them. The incidence of syphilis (using as a criterion RPR posi2vo confirmed by TPPA) was 1.5% (95% CI, 0.3–4.3) in TGU men compared to 3.3% (95% CI, 0.9–8.2) in SPS men, While in TGU women it was 0.8% (95% CI, 0.0–4.5) compared to 7.5% (CI 95%, 1.6–20.4) of SPS women. <h3>Conclusion</h3> HIV prevalence is higher in San Pedro Sula than in Tegucigalpa, as is the incidence of syphilis, but the highest of all is the prevalence of cumulative syphilis, which implies that there is unprotected sex and high risk. Also, while most know where to perform the HIV test only half were performed and the syphilis test less than a third. One-third of men and women suffered from discrimination and PPL discrimination, with verbal attacks (threats, scoldings, humiliations) among the 2p of attacks, and less than one-twentieth reported this discrimination.
Prevalence of Maternal Chagas Disease and Vertical Transmission Rates in Bolivia: A Systematic Review and Meta-Analysis
(American Society of Tropical Medicine and Hygiene, 2024) Freddy Tinajeros; Beatriz Amparo Rodríguez-Olguin; Melissa Klein Cutshaw
Bolivia has one of the highest burdens of Chagas disease in the world. Vertical transmission from mother to infant accounts for a growing number of cases. We performed a systematic review of articles assessing the prevalence of Chagas disease in pregnant women and rates of vertical transmission to infants in Bolivia. Studies were not excluded based on year of publication or language. Random-effects analyses were performed to estimate a pooled prevalence of maternal Chagas disease and pooled vertical transmission rate. Our search yielded 21 articles describing over 400,000 cases of Chagas disease among pregnant women in Bolivia. The reported prevalence of maternal Chagas disease ranged from 17.3% to 64.5%, with a pooled prevalence of 33.0% (95% CI, 27.4-38.7%). The prevalence of maternal Chagas disease trended down over time (P = 0.006), decreasing by approximately 25% to 30% over the last 40 years. Vertical transmission rates ranged from 2.0% to 13% with a pooled average of 6.2% (95% CI, 4.4-7.5%); rates did not significantly change over time. Our study is the first systematic review and meta-analysis of Chagas disease maternal prevalence and vertical transmission in Bolivia. Our findings indicate that maternal Chagas disease has fallen in prevalence but still affects 20% to 30% of pregnant women and poses a considerable risk of vertical transmission. Pregnant women and infants are an important target for public health interventions to limit the mortality and morbidity of Chagas disease and to reduce intergenerational spread.
Risk Factors for Maternal Chagas Disease and Vertical Transmission in a Bolivian Hospital
(Oxford University Press, 2020) Melissa D. Klein; Freddy Tinajeros; María del Carmen Menduiña; Edith Málaga; Beth Jessy Condori; Manuela Verástegui; Federico Urquizu; Robert H. Gilman; Natalie M. Bowman
Although improved access to screening and qPCR increased the number of infants diagnosed with congenital Chagas disease, many infants remain undiagnosed. A better understanding of risk factors and improved access to highly sensitive and specific diagnostic techniques for congenital Chagas disease may help improve regional initiatives to reduce disease burden.
Sífilis materna y congénita en cuatro provincias de Bolivia
(Instituto Nacional de Salud Pública, 2007) Rita Revollo; Freddy Tinajeros; Carolina Hilari; Sandra G. García; Lourdes Zegarra; Claudia Dı́az-Olavarrieta; Carlos J Conde-González
Rapid syphilis tests constitute an important tool to strengthen early diagnosis of syphilis during pregnancy. Preventing congenital and maternal syphilis in Bolivia remains a public health priority.
Target product profile for the development of pediatric formulations of new drugs for the treatment of children with T. cruzi infection
(Public Library of Science, 2026) Colin Forsyth; Facundo Garcia-Bournissen; Guillermo Moscatelli; Samanta Moroni; Ana Cristina Pereiro; Lourdes Ortiz-Daza; Elvira-Idalia Hernández Cuevas; Freddy Tinajeros; Tayná Marques; Andrea Marchiol
The TPP provides guidance for essential and ideal characteristics of formulations of new drugs for the treatment of children with T. cruzi infection.
VP44.17: Surgeon training is a crucial factor in the management of placenta accreta spectrum in hospitals with limited resources
(Wiley, 2021) L.M. Mojica Palacios; L.R. Aguilera Daga; Freddy Tinajeros; J.D. Farfán Choque; Mayo Robles; I.P. Ticona Uchani; A. Quintanilla; Lina María Vergara-Galliadi; A. Hidalgo Cardona; Albaro José Nieto‐Calvache
Placenta accreta spectrum (PAS) is a serious pathology, it is recommended that the management of this condition be done in centres of excellence. However, those hospitals are not available in many low and middle income countries (LMICs). We seek to describe the process of prenatal diagnosis, surgical management, and postnatal pathological analysis in a referral hospital for severe obstetric pathology in an LMIC. This is a descriptive, retrospective study including patients with intraoperative diagnosis of PAS between January 2019 and December 2020, treated at the Dr. Percy Boland Rodríguez Women's Hospital, in Santa Cruz de la Sierra, Bolivia. 110 patients with an intraoperative PAS diagnosis were included. 39 of them had a prenatal ultrasound diagnosis (Group 1, 35.4%) and in the remaining 71 (Group 2, 64.6%) the diagnosis of PAS was intraoperative. Although all the patients included had intraoperative confirmation of PAS and hysterectomy, 34 of them (31%) did not have a histological study of the uterus. The frequency of admission to the ICU, ureteral injury, bladder injury and surgical reintervention was low (14.5%, 0.018%, 0.054% and 0.036%, respectively). There were no maternal deaths. Despite the low frequency of prenatal diagnosis, the frequency of complications and the need for transfusion of more than 4 UGRE (8.1%) was low. Probably the high exposure of surgeons to this disease (110 patients in 22 months) favour surgical expertise and explain the good results despite limited resources. The frequency of prenatal diagnosis (35.4%) and the availability of postnatal histological study (69%) were very low in the studied population. Surgical skill, favoured by a high flow of patients, is an important factor in preventing complications in settings with limited resources.