Acute Chagas disease outbreaks in Colombia in 2019.

This study seeks to address the critical knowledge gap surrounding the acute phase of Chagas disease in Colombia, with a specific focus on cases reported in 2019. The acute phase of Chagas disease is a pivotal period for intervention, yet it remains poorly understood, particularly in regions where oral transmission is presumed to be a significant factor. By analyzing these recent cases, our research aims to provide a deeper understanding of the dynamics of Chagas disease during its acute phase in Colombia in 2019. This understanding is essential not only for improving disease management and treatment strategies but also for enhancing public health responses to this neglected tropical disease. In particular, our study highlights the importance of identifying and addressing the unique challenges posed by oral transmission routes, which have been increasingly recognized within Colombia's Chagas disease landscape.

Addressing Chagas disease from a One Health perspective: risk factors, lessons learned and prevention of oral transmission outbreaks in Colombia.

Background: Chagas disease (CD) is transmitted by vectors but can also be transmitted orally through contaminated food, drinks, or meat. The One Health perspective aims to understand the complex interaction between human, animal, and environmental health in controlling disease. This study analyzed risk factors and drew lessons from past outbreaks of orally transmitted CD to develop effective preventive strategies. Methods: A simultaneous mixed methods study was conducted. The study consisted of two phases: an ecological epidemiological analysis at the municipal level using secondary data spanning from 1992 to 2023, and semistructured interviews with health providers and policymakers at the national level in Colombia. The results from both phases were triangulated to gain a comprehensive understanding of the topic. Results: A total of 64 outbreaks, infecting 302 individuals, were reported. Most of these outbreaks (89.2%) were classified as family-related, and they occurred most frequently during the months of April to June (46.6%). It is worth noting that a significant number of these outbreaks took place in municipalities that lacked vector control plans. Risk factors for oral transmission included the location of food preparation, poor housing quality, food preparation water source, the presence of vectors/marsupials, forest type, and climatic variables. Interviews conducted emphasized the importance of implementing outbreak plans and providing staff training to effectively address the issue. Conclusion: A One Health approach strengthening prevention, surveillance, case management and cross-sectoral collaboration is needed to control outbreaks and reduce transmission in Colombia. Preparedness plans and education of health professionals are also important. This study identified modifiable risk factors to guide public health interventions.

The Development of a One-Step RT-qPCR for the Detection and Quantification of Viable Forms of Trypanosoma cruzi in Açai Samples from Areas at Risk of Chagas Disease through Oral Transmission.

Currently, approximately 70% of new cases of Chagas disease (CD) in Brazil are attributed to oral transmission, particularly through foods such as açaí, bacaba, and sugarcane juice, primarily in the northern and northeastern regions of the country. This underscores the imperative need to control the spread of the disease. The methods utilized to conduct quality control for food associated with outbreaks and to assess the potential for the oral transmission of CD through consuming açaí primarily rely on isolating the parasite or inoculating food into experimental animals, restricting the analyses to major research centers. While there are existing studies in the literature on the detection and quantification of T. cruzi DNA in açaí, the evaluation of parasites' viability using molecular methods in this type of sample and differentiating between live and dead parasites in açaí pulp remain challenging. Consequently, we developed a molecular methodology based on RT-qPCR for detecting and quantifying viable T. cruzi in açaí pulp samples. This protocol enables the stabilization and preservation of nucleic acids in açaí, along with incorporating an exogenous internal amplification control. The standardization of the RNA extraction method involved a simple and reproducible approach, coupled with a one-step RT-qPCR assay. The assay underwent validation with various T. cruzi DTUs and demonstrated sensitivity in detecting up to 0.1 viable parasite equivalents/mL in açaí samples. Furthermore, we investigated the effectiveness of a bleaching method in eliminating viable parasites in açaí samples contaminated with T. cruzi by comparing the detection of DNA versus RNA. Finally, we validated this methodology using açaí pulp samples positive for T. cruzi DNA, which were collected in a municipality with a history of oral CD outbreaks (Coari-AM). This validation involved comparing the detection and quantification of total versus viable T. cruzi. Collectively, our findings demonstrate the feasibility of this methodology in detecting viable forms of T. cruzi in açaí pulp samples, emerging as a crucial tool for monitoring oral outbreaks of Chagas disease resulting from açaí consumption.

Oral Chagas Disease in Colombia-Confirmed and Suspected Routes of Transmission.

Chagas disease (CD) remains endemic throughout many regions of Colombia despite implementing decades of vector control strategies in several departments. Some regions have had a significant decrease in vectorial transmission, but the oral ingestion of Trypanosoma cruzi through consumption of contaminated food and drink products is increasingly described. This form of transmission has important public health relevance in Colombia due to an increase in reported acute CD cases and clinical manifestations that often lead to significant morbidity and mortality. Oral CD in Colombia has been associated with the consumption of contaminated fruit juices, such as palm wine, sugar cane, or tangerine juice and water for consumption, or contaminated surfaces where food has been prepared. Another interesting route of oral transmission includes ingestion of unbeknownst infected armadillos' blood, which is related to a traditional medicine practice in Colombia. Some earlier reports have also implemented consumption of infected bush meat as a source, but this is still being debated. Within the Amazon Basin, oral transmission is now considered the principal cause of acute CD in these regions. Furthermore, new cases of acute CD are now being seen in departments where CD has not been documented, and triatomine vectors are not naturally found, thus raising suspicion for oral transmission. The oral CD could also be considered a food-borne zoonosis, and odoriferous didelphid secretions have been implemented in contaminating the human dwelling environment, increasing the risk of consumption of infectious metacyclic trypomastigotes. In this article, we will discuss the complex transmission dynamics of oral CD in Colombia and further examine the unique clinical manifestations of this route of infection. New insights into the oral transmission of Trypanosoma cruzi are being discovered in Colombia, which can help bring increased awareness and a better understanding of this neglected tropical disease to reduce the burden of CD throughout Latin America.

Availability of Hand Sanitizers in Food Establishments of New York City: An Observational Study.

Hand hygiene is a crucial tool to limit the transmission of common respiratory and gastrointestinal infections. While hand sanitizers were ubiquitous early in the COVID-19 pandemic, the number of food establishments that have adequately maintained them remains unknown. Through systematic observations in 89 New York City food establishments, we found that hand sanitizer dispensers were present in only 40% of the stores, and only 23% had functional ones. This scarcity highlights the necessity of providing ongoing support to small business owners nationwide to promote and maintain primary prevention measures at all times, extending beyond periods of public health crises.

Putative 14th Century Outbreak of Foodborne Chagas Disease, Mexico.

A severe epidemic erupted in Coyoacán at the southern end of Lake Texcoco, in Central Mexico, around 1330. Chroniclers of the 16th century reported that after disrupted fish supply, the inhabitants of Coyoacán had suffered high morbidity and mortality. They developed edema of their eyelids, face, and feet, and hemorrhagic diarrhea. Many died, mainly the young and the old. Pregnant women miscarried. The disease is classically considered an illness of nutritional origin. However, its clinical picture and the circumstances of its emergence are remarkably consistent with an outbreak of foodborne Chagas disease, possibly acquired upon the hunting and consumption of alternative food sources, such as infected opossums (Didelphis spp.), unique reservoirs of Trypanosoma cruzi.

Acute Chagas disease associated with ingestion of contaminated food in Brazilian western Amazon.

OBJECTIVE: To describe clinical, epidemiological and management information on cases of acute Chagas disease (ACD) by oral transmission in the state of Amazonas in western Amazon. METHODS: Manual and electronic medical records of patients diagnosed with ACD at the Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD) were included. RESULTS: There were 147 cases of acute CD registered from 10 outbreaks that occurred in the state of Amazonas between 2004 and 2022. The transmission pathway was through oral route, with probable contaminated palm fruit juice (açaí and/or papatuá), and involved people from the same family, friends or neighbours. Of 147 identified cases, 87 (59%) were males; cases were aged 10 months to 82 years. The most common symptom was the febrile syndrome (123/147; 91.8%); cardiac alterations were present in 33/100 (33%), (2/147; 1.4%) had severe ACD with meningoencephalitis, and 12 (8.2%) were asymptomatic. Most cases were diagnosed through thick blood smear (132/147; 89.8%), a few (14/147; 9.5%) were diagnosed by serology and (1/147; 0.7%) by polymerase chain reaction (PCR) and blood culture. In all these outbreaks, 74.1% of the patients were analysed by PCR, and Trypanosoma cruzi TcIV was detected in all of them. No deaths were recorded. The incidence of these foci coincided with the fruit harvest period in the state of Amazonas. CONCLUSION: The occurrence of ACD outbreaks in the Amazon affected individuals of both sexes, young adults, living in rural and peri-urban areas and related to the consumption of regional foods. Early diagnosis is an important factor in surveillance. There was a low frequency of cardiac alterations. Continuous follow-up of most patients was not carried out due to difficulty in getting to specialised centres; therefore, little is known about post-treatment.

Chorioamnionitis and early pregnancy loss caused by ampicillin-resistant non-typeable Haemophilus influenzae.

Haemophilus influenzae can cause intra-amniotic infection and early pregnancy loss. The mode of transmission and risk factors for H. influenzae uterine cavity infections are unknown. Here, we present the case of chorioamnionitis caused by ampicillin-resistant H. influenzae in a 32-year-old Japanese woman at 16 weeks of gestation. Despite empirical treatment, including ampicillin, as recommended by the current guidelines, she had fetal loss. The antimicrobial regimen was changed to ceftriaxone, and the treatment was completed without complications. Although the prevalence and risk factors for chorioamnionitis caused by ampicillin-resistant H. influenzae are unknown, clinicians need to recognize H. influenzae as a potentially drug-resistant and lethal bacterium for pregnant women.

A Randomized Clinical Trial of 1-Dose vs Accelerated 2-Dose Schedule for Hepatitis A Virus (HAV) Revaccination Among People With Human Immunodeficiency Virus Who Were Nonresponders or Had Seroreversion After Primary HAV Vaccination.

BACKGROUND: For people with human immunodeficiency virus (PWH) who have no serological responses to their primary hepatitis A virus (HAV) vaccination or have seroreversion after successful primary vaccination, the optimal revaccination strategy remains unclear. METHODS: In this open-label, randomized clinical trial, PWH who tested negative for anti-HAV antibodies after receiving a standard 2-dose series of primary HAV vaccination were enrolled and assigned in a 1:1 ratio to receive either 1 dose (the 1-dose group) or 2 doses of HAV vaccine administered 4 weeks apart (the 2-dose group). Serological response rates and anti-HAV antibody titers were compared at weeks 24 and 48. RESULTS: Of the 153 participants (77 in the 1-dose group and 76 in the 2-dose group), the overall serological response rates at week 48 after revaccination were similar between the 2 groups (2- vs 1-dose, 80.2% vs 71.4%, P = .20). However, anti-HAV antibody titers were consistently higher in the 2-dose group than in the 1-dose group. In subgroup analysis, PWH who were nonresponders to primary HAV vaccination were significantly more likely to mount a serological response after 2-dose HAV revaccination (68.4% vs 44.1%, P = .038). No severe adverse events were reported throughout the study. CONCLUSIONS: Two-dose HAV revaccination administered 4 weeks apart yielded similar serological responses as 1-dose revaccination among PWH who were nonresponders or had seroreversion after primary HAV vaccination. The 2-dose revaccination schedule generated significantly higher anti-HAV antibody titers and was more likely to elicit serological responses at week 48 among PWH who were nonresponders to primary HAV vaccination. Clinical Trials Registration. NCT03855176.

Prolonged Streptococcus gallolyticus subsp. pasteurianus gut colonization in healthcare workers and potential transmission role in neonatal sepsis.

BACKGROUND: Streptococcus gallolyticus subsp. pasteurianus (SGSP) is a commensal in the intestinal tract and a potential pathogen of neonatal sepsis. During an 11-month period, four consecutive cases of SGSP sepsis were identified in one postnatal care unit (unit A) without evidence of vertical transmission. Therefore, we initiated this study to investigate the reservoir and mode of transmission of SGSP. METHOD: We performed cultures of stool samples from healthcare workers in unit A and unit B (another unit without SGSP sepsis). If SGSP was positive in feces, we performed isolate pulsotyping and genotyping by using pulsed-field gel electrophoresis (PFGE) and analyzing random amplified polymorphic DNA (RAPD) patterns, respectively. RESULTS: Five staff members in unit A showed positivity for SGSP. All samples from unit B were negative. We identified two major pulsogroups (groups C and D) by PFGE. In group D, the strains isolated from 3 consecutive sepsis patients (P1, P2 and P3) were closely related and clustered together as those from 2 staff members (C1/C2, C6). One staff (staff 4) had a direct contact history with patient (P1) confirmed to have the same clone. The last isolate of the patient in our study (P4) belonged to a distinct clone. CONCLUSION: We found prolonged gut colonization of SGSP in healthcare workers and its epidemiological relatedness to neonatal sepsis. Fecal-oral or contact transmission is a possible route of SGSP infection. Fecal shedding among staff may be associated with neonatal sepsis in healthcare facilities.

Large-scale iterated singing experiments reveal oral transmission mechanisms underlying music evolution.

Speech and song have been transmitted orally for countless human generations, changing over time under the influence of biological, cognitive, and cultural pressures. Cross-cultural regularities and diversities in human song are thought to emerge from this transmission process, but testing how underlying mechanisms contribute to musical structures remains a key challenge. Here, we introduce an automatic online pipeline that streamlines large-scale cultural transmission experiments using a sophisticated and naturalistic modality: singing. We quantify the evolution of 3,424 melodies orally transmitted across 1,797 participants in the United States and India. This approach produces a high-resolution characterization of how oral transmission shapes melody, revealing the emergence of structures that are consistent with widespread musical features observed cross-culturally (small pitch sets, small pitch intervals, and arch-shaped melodic contours). We show how the emergence of these structures is constrained by individual biases in our participants-vocal constraints, working memory, and cultural exposure-which determine the size, shape, and complexity of evolving melodies. However, their ultimate effect on population-level structures depends on social dynamics taking place during cultural transmission. When participants recursively imitate their own productions (individual transmission), musical structures evolve slowly and heterogeneously, reflecting idiosyncratic musical biases. When participants instead imitate others' productions (social transmission), melodies rapidly shift toward homogeneous structures, reflecting shared structural biases that may underpin cross-cultural variation. These results provide the first quantitative characterization of the rich collection of biases that oral transmission imposes on music evolution, giving us a new understanding of how human song structures emerge via cultural transmission.

Solar desalination/purification (solar stills, humidification-dehumidification, solar disinfection) in high altitude during COVID19: Insights of gastrointestinal manifestations and systems' mechanism.

From the starting of the pandemic different transmission routes of the pathogen was brought into the spotlight by researchers from different disciplines. This matter in high-altitudes was more boosted as the main parameters were not exactly realized. In this review we are about to highlight the possibility of consuming contaminated water generated form solar water desalination/disinfection systems in highlands. Three systems including solar still, solar disinfection (which experimented by the authors in 2019 in high altitude) and humidification-dehumidification were consider in this context. Ascribe to the risks of pathogens transmission in solar desalination/disinfection systems where the water resources are heavily polluted in every corner of the world, highlighting the risk of consuming water in high-altitude where there are many other parameters associated with spread of pathogen is of great importance. As it was reported, reliability of solar desalination and solar water disinfections systems against contaminated water by the novel coronavirus remained on the question because the virus can be transmitted by vapor in solar stills due to tiny particle size (60-140 nm) and would not be killed by solar disinfections due to low-temperature of operation <40 °C while for HDH contamination of both water and air by sars-cov-2 could be a concern. Although the SARS-CoV-2 is not a waterborne pathogen, its capability to replicate in stomach and infection of gastrointestinal glandular suggested the potential of transmission via fecal-oral. Eventually, it was concluded that using solar-based water treatment as drinking water in high altitude regions should be cautiously consider and recommendations and considerations are presented. Importantly, this critical review not only about the ongoing pandemic, but it aims is to highlight the importance of produced drinking water by systems for future epidemic/pandemic to prevent spread and entering a pathogen particularly in high-altitude regions via a new routes.

Genetic Characterization of Trypanosoma cruzi I Populations from an Oral Chagas Disease Outbreak in Venezuela: Natural Resistance to Nitroheterocyclic Drugs.

The oral transmission of Chagas disease (oCD) in Venezuela announced its appearance in 2007. Different from other populations affected by oCD and despite close supervision during treatment with nitroheterocyclic drugs, the result was treatment failure. We studied genetic features of natural bloodstream parasite populations and populations after treatment of nine patients of this outbreak. In total, we studied six hemoculture isolates, eight Pre-Tx blood samples, and 17 samples collected at two or three Post-Tx time-points between 2007 and 2015. Parasitic loads were determined by quantitative polymerase chain reaction (qPCR), and discrete typing units (DTU), minicircle signatures, and Tcntr-1 gene sequences were searched from blood samples and hemocultures. Half-maximal inhibitory concentration (IC50) values were measured from the hemocultures. All patients were infected by TcI. Significant decrease in parasitic loads was observed between Pre-Tx and Post-Tx samples, suggesting the evolution from acute to chronic phase of Chagas disease. 60% of intra-DTU-I variability was observed between Pre-Tx and Post-Tx minicircle signatures in the general population, and 43 single-nucleotide polymorphisms (SNPs) were detected in a total of 12 Tcntr-1 gene sequences, indicative of a polyclonal source of infection. SNPs in three post-Tx samples produced stop codons giving rise to putative truncated proteins or displaced open reading frames, which would render resistance genes. IC50 values varied from 5.301 ± 1.973 to 104.731 ± 4.556 µM, demonstrating a wide range of susceptibility. The poor drug response in the Pre-Tx parasite populations may be associated with the presence of naturally resistant parasite clones. Therefore, any information that can be obtained on drug susceptibility from in vitro assays, in vivo assays, or molecular characterization of natural populations of Trypanosoma cruzi becomes essential when therapeutic guidelines are designed in a given geographical area.

Impact of temperature on infection with Japanese encephalitis virus of three potential urban vectors in Taiwan; Aedes albopictus, Armigeres subalbatus, and Culex quinquefasciatus.

Japanese encephalitis (JE) is an important mosquito-borne infectious disease in rural areas of Asia that is caused by Japanese encephalitis virus (JEV). Culex tritaeniorhynchus is the major vector of JEV, nevertheless there are other mosquitoes that may be able to transmit JEV. This study confirms that the midgut, head tissue, salivary glands, and reproductive tissue of Aedes albopictus, Armigeres subalbatus, and Culex quinquefasciatus are all able to be infected with JEV after a virus-containing blood meal was ingested by female mosquitoes. Even though the susceptibility to JEV of the different tissues varies, the virus-positive rate increased with the number of days after JEV infection. Moreover, once JEV escapes the midgut barrier, the oral transmission rates of JEV were 16%, 2%, and 21% for Ae. albopictus, Ar. subalbatus, and Cx. quinquefasciatus at 14 days after infection at 30 °C, respectively. There is no supporting evidence to suggest vertical transmission of JEV by the tested mosquitoes. Collectively, raising the temperature enhances JEV replication in the salivary gland of the three mosquito species, suggesting that global warming will enhance mosquito vector competence and that this is likely to lead to an increase in the probability of JEV transmission.

Guideline of the Brazilian Society of Cardiology on Diagnosis and Treatment of Patients with Chagas Disease Cardiomyopathy / Diretriz da Sociedade Brasileira de Cardiologia sobre Diagnóstico e Tratamento de Pacientes com Cardiomiopatia da Doença de Chagas

This guideline aimed to update the concepts and formulate the standards of conduct and scientific evidence that support them, regarding the diagnosis and treatment of the Cardiomyopathy of Chagas disease, with special emphasis on the rationality base that supported it.  Chagas disease in the 21st century maintains an epidemiological pattern of endemicity in 21 Latin American countries. Researchers and managers from endemic and non-endemic countries point to the need to adopt comprehensive public health policies to effectively control the interhuman transmission of T. cruzi infection, and to obtain an optimized level of care for already infected individuals, focusing on diagnostic and therapeutic opportunistic opportunities.   Pathogenic and pathophysiological mechanisms of the Cardiomyopathy of Chagas disease were revisited after in-depth updating and the notion that necrosis and fibrosis are stimulated by tissue parasitic persistence and adverse immune reaction, as fundamental mechanisms, assisted by autonomic and microvascular disorders, was well established. Some of them have recently formed potential targets of therapies.  The natural history of the acute and chronic phases was reviewed, with enhancement for oral transmission, indeterminate form and chronic syndromes. Recent meta-analyses of observational studies have estimated the risk of evolution from acute and indeterminate forms and mortality after chronic cardiomyopathy. Therapeutic approaches applicable to individuals with Indeterminate form of Chagas disease were specifically addressed. All methods to detect structural and/or functional alterations with various cardiac imaging techniques were also reviewed, with recommendations for use in various clinical scenarios. Mortality risk stratification based on the Rassi score, with recent studies of its application, was complemented by methods that detect myocardial fibrosis.  The current methodology for etiological diagnosis and the consequent implications of trypanonomic treatment deserved a comprehensive and in-depth approach. Also the treatment of patients at risk or with heart failure, arrhythmias and thromboembolic events, based on pharmacological and complementary resources, received special attention. Additional chapters supported the conducts applicable to several special contexts, including t. cruzi/HIV co-infection, risk during surgeries, in pregnant women, in the reactivation of infection after heart transplantation, and others.     Finally, two chapters of great social significance, addressing the structuring of specialized services to care for individuals with the Cardiomyopathy of Chagas disease, and reviewing the concepts of severe heart disease and its medical-labor implications completed this guideline.

Esta diretriz teve como objetivo principal atualizar os conceitos e formular as normas de conduta e evidências científicas que as suportam, quanto ao diagnóstico e tratamento da CDC, com especial ênfase na base de racionalidade que a embasou. A DC no século XXI mantém padrão epidemiológico de endemicidade em 21 países da América Latina. Investigadores e gestores de países endêmicos e não endêmicos indigitam a necessidade de se adotarem políticas abrangentes, de saúde pública, para controle eficaz da transmissão inter-humanos da infecção pelo T. cruzi, e obter-se nível otimizado de atendimento aos indivíduos já infectados, com foco em oportunização diagnóstica e terapêutica. Mecanismos patogênicos e fisiopatológicos da CDC foram revisitados após atualização aprofundada e ficou bem consolidada a noção de que necrose e fibrose sejam estimuladas pela persistência parasitária tissular e reação imune adversa, como mecanismos fundamentais, coadjuvados por distúrbios autonômicos e microvasculares. Alguns deles recentemente constituíram alvos potenciais de terapêuticas. A história natural das fases aguda e crônica foi revista, com realce para a transmissão oral, a forma indeterminada e as síndromes crônicas. Metanálises recentes de estudos observacionais estimaram o risco de evolução a partir das formas aguda e indeterminada e de mortalidade após instalação da cardiomiopatia crônica. Condutas terapêuticas aplicáveis aos indivíduos com a FIDC foram abordadas especificamente. Todos os métodos para detectar alterações estruturais e/ou funcionais com variadas técnicas de imageamento cardíaco também foram revisados, com recomendações de uso nos vários cenários clínicos. Estratificação de risco de mortalidade fundamentada no escore de Rassi, com estudos recentes de sua aplicação, foi complementada por métodos que detectam fibrose miocárdica. A metodologia atual para diagnóstico etiológico e as consequentes implicações do tratamento tripanossomicida mereceram enfoque abrangente e aprofundado. Também o tratamento de pacientes em risco ou com insuficiência cardíaca, arritmias e eventos tromboembólicos, baseado em recursos farmacológicos e complementares, recebeu especial atenção. Capítulos suplementares subsidiaram as condutas aplicáveis a diversos contextos especiais, entre eles o da co-infecção por T. cruzi/HIV, risco durante cirurgias, em grávidas, na reativação da infecção após transplante cardíacos, e outros.    Por fim, dois capítulos de grande significado social, abordando a estruturação de serviços especializados para atendimento aos indivíduos com a CDC, e revisando os conceitos de cardiopatia grave e suas implicações médico-trabalhistas completaram esta diretriz. 

Oral and Intragastric: New Routes of Infection by Leishmania braziliensis and Leishmania infantum?

Although Leishmania transmission in nature is associated with the bite of an infected sandfly vector, other possible transmission routes are speculated to occur, such as the oral route. We evaluated the possibility of infection by this route in golden hamsters (Mesocricetus auratus) using Leishmania braziliensis (Lb) and Leishmania infantum (Li). Hamsters were exposed to experimental oral or intragastrical infection with axenic promastigotes, besides oral ingestion of a suspension of cultivated macrophages infected with amastigotes, lesion-fed Lutzomyia longipalpis, skin lesion or infective spleen fragment. The parasite's isolation, besides a positive PCR and IFAT, confirmed the intragastric infection by promastigote parasites. The oral ingestion of macrophages infected with L. braziliensis amastigotes was also infective. These results confirmed that Leishmania parasites could infect mammals by the intragastric route through the ingestion of promastigote forms (what can happen after a sandfly ingestion) and by the oral ingestion of infected macrophages (what can happen in nature in a predator-prey interaction). The better understanding of these alternative routes is essential to understand their transmission dynamics in nature. As far as we know, this is the first time that oral and intragastric Leishmania transmission has been experimentally demonstrated, constituting new infection routes, at least for L. infantum and L. braziliensis.

Manifestaciones Gastrointestinales de COVID-19: puesta al día y revisión de literatura / Gastrointestinal Manifestations of COVID-19: update and literature review

The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a single-stranded RNA virus belonging to the beta coronavirus family, it is the cause of the COVID-19 disease and the pandemic that has revolutionized and challenged the medical research profession and health systems around the world. With the first coronavirus SARS-CoV, the important role of the angiotensin 2-converting enzyme (ACE2) in the pathophysiology of the disease caused by the virus was discovered, a discovery that would lay the foundations on which research on the new coronavirus is based. The virus is capable of producing disease with a wide spectrum of clinical presentation, from asymptomatic patients to patients with severe acute respiratory distress syndrome (ARDS) requiring admission to intensive care units (ICU). The most commonly described symptoms are fever, cough, myalgia, and dyspnea. However, and with advances in the knowledge of SARS-CoV-2 infection, it has been discovered that gastrointestinal (GI) symptoms are frequent and have been associated with severe disease. Viral RNA has been found in feces, urine, blood, and other fluids, which could mean that there are other routes of infection that have not been considered a threat by the medical community until now. In this article, an updated bibliographic review of this topic is presented, with articles selected from the PubMed platform.

Characteristics of COVID-19 Patients With SARS-CoV-2 Positivity in Feces.

Background: SARS-CoV-2 is highly contagious and poses a great threat to epidemic control and prevention. The possibility of fecal-oral transmission has attracted increasing concern. However, viral shedding in feces has not been completely investigated. Methods: This study retrospectively reviewed 97 confirmed coronavirus disease 2019 (COVID-19) patients hospitalized at the First Affiliated Hospital, School of Medicine, Zhejiang University, from January 19 to February 17, 2020. SARS-CoV-2 RNA in samples of sputum, nasopharyngeal or throat swabs, bronchoalveolar lavage and feces was detected by real-time reverse transcription polymerase chain reaction (RT-PCR). Clinical characteristics and parameters were compared between groups to determine whether fecal RNA was positive. Results: Thirty-four (35.1%) of the patients showed detectable SARS-CoV-2 RNA in feces, and 63 (64.9%) had negative detection results. The median time of viral shedding in feces was approximately 25 days, with the maximum time reaching 33 days. Prolonged fecal-shedding patients showed longer hospital stays. Those patients for whom fecal viral positivity persisted longer than 3 weeks also had lower plasma B-cell counts than those patients in the non-prolonged group [70.5 (47.3-121.5) per µL vs. 186.5 (129.3-376.0) per µL, P = 0.023]. Correlation analysis found that the duration of fecal shedding was positively related to the duration of respiratory viral shedding (R = 0.70, P < 0.001) and negatively related to peripheral B-cell counts (R = -0.44, P < 0.05). Conclusions: COVID-19 patients who shed SARS-CoV-2 RNA in feces presented similar clinical characteristics and outcomes as those who did not shed SARS-CoV-2 RNA in feces. The prolonged presence of SARS-CoV-2 nucleic acids in feces was highly correlated with the prolonged shedding of SARS-CoV-2 RNA in the respiratory tract and with lower plasma B-cell counts.

Potential intestinal infection and faecal-oral transmission of human coronaviruses.

Human coronaviruses (HCoVs) were first described in 1960s for patients experiencing common cold. Since then, increasing number of HCoVs have been discovered, including those causing severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and the circulating coronavirus disease 2019 (COVID-19), which can cause fatal respiratory disease in humans on infection. HCoVs are believed to spread mainly through respiratory droplets and close contact. However, studies have shown that a large proportion of patients with HCoV infection develop gastrointestinal (GI) symptoms, and many patients with confirmed HCoV infection have shown detectable viral RNA in their faecal samples. Furthermore, multiple in vitro and in vivo animal studies have provided direct evidence of intestinal HCoV infection. These data highlight the nature of HCoV GI infection and its potential faecal-oral transmission. Here, we summarise the current findings on GI manifestations of HCoVs. We also discuss how HCoV GI infection might occur and the current evidence to establish the occurrence of faecal-oral transmission.

Study of the correlation between Covid-19 cases and deaths and basic sanitation in Brazil: Is this a possible secondary route of virus transmission?

People with COVID-19 may excrete viable SARS-CoV-2 virus through urine and faeces, which has raised concerns about the possibility of transmission of COVID-19 via water contaminated or sewage. These concerns are especially exacerbated in underdeveloped countries like Brazil, where untreated sewage is usually discharged to surface water or soil. Because of that, a hypothesis emerged that was addressed in this study, which seeks to understand whether access to basic sanitation services can influence the proliferation of the virus. A correlation study was carried out between the cases of COVID-19 and the indicators of basic sanitation from all regions of Brazil. The results showed that there was a correlation only with the water supply indicator. A hypothesis that would explain the presented correlation would be the inefficiency of the water treatment systems in Brazil, not totally inactivating the virus, or possible contamination of the water distribution networks by sanitary sewage. In general, the data presented reinforce the need to expand and monitor basic sanitation services, especially to ensure the effective and efficient disinfection of drinking water. This monitoring could be useful for early warning surveillance of the spread of the virus.