YELLOW ALERT: Persistent Yellow Fever Virus Circulation among Non-Human Primates in Urban Areas of Minas Gerais State, Brazil (2021-2023)

Yellow fever virus (YFV) is the agent of yellow fever (YF), which affects both humans and non-human primates (NHP). Neotropical NHP are highly susceptible to YFV and considered sentinels for YFV circulation. Brazil faced a significant YF outbreak in 2017-2018, with over 2000 human cases and 2000 epizootics cases, mainly in the State of Minas Gerais, Brazil. This study aimed to investigate whether YFV circulation persisted in NHP after the human outbreak had subsided. To this end, NHP carcass samples collected in Minas Gerais from 2021 to 2023 were screened for YFV. RNA was extracted from tissue fragments and used in RT-qPCR targeting the YFV 5'UTR. Liver and lung samples from 166 animals were tested, and the detection of the β-actin mRNA was used to ensure adequacy of RNA isolation. YFV RNA was detected in the liver of 18 NHP carcasses collected mainly from urban areas in 2021 and 2022. YFV positive NHP were mostly represented by Callithrix, from 5 out of the 12 grouped municipalities (mesoregions) in Minas Gerais state. These findings reveal the continued YFV circulation in NHP in urban areas of Minas Gerais during 2021 and 2022, with the attendant risk of re-establishing the urban YFV cycle.

Ecological drivers of sustained enzootic yellow fever virus transmission in Brazil, 2017-2021

Beginning December 2016, sylvatic yellow fever (YF) outbreaks spread into southeastern Brazil, and Minas Gerais state experienced two sylvatic YF waves (2017 and 2018). Following these massive YF waves, we screened 187 free-living non-human primate (NHPs) carcasses collected throughout the state between January 2019 and June 2021 for YF virus (YFV) using RTqPCR. One sample belonging to a Callithrix, collected in June 2020, was positive for YFV. The viral strain belonged to the same lineage associated with 2017-2018 outbreaks, showing the continued enzootic circulation of YFV in the state. Next, using data from 781 NHPs carcasses collected in 2017-18, we used generalized additive mixed models (GAMMs) to identify the spatiotemporal and host-level drivers of YFV infection and intensity (an estimation of genomic viral load in the liver of infected NHP). Our GAMMs explained 65% and 68% of variation in virus infection and intensity, respectively, and uncovered strong temporal and spatial patterns for YFV infection and intensity. NHP infection was higher in the eastern part of Minas Gerais state, where 2017-2018 outbreaks affecting humans and NHPs were concentrated. The odds of YFV infection were significantly lower in NHPs from urban areas than from urban-rural or rural areas, while infection intensity was significantly lower in NHPs from urban areas or the urban-rural interface relative to rural areas. Both YFV infection and intensity were higher during the warm/rainy season compared to the cold/dry season. The higher YFV intensity in NHPs in warm/rainy periods could be a result of higher exposure to vectors and/or higher virus titers in vectors during this time resulting in the delivery of a higher virus dose and higher viral replication levels within NHPs. Further studies are needed to better test this hypothesis and further compare the dynamics of YFV enzootic cycles between different seasons.

Wild-type Yellow fever virus in cerebrospinal fluid from fatal cases in Brazil, 2018

Yellow fever virus (YFV) is the causative agent of yellow fever (YF), a hemorrhagic and viscerotropic acute disease. Severe YF has been described in approximately 15-25% of YF patients, with 20-50% of severe YF cases being fatal. Here we analyzed cerebrospinal fluid (CSF) samples collected during the YF outbreak in Brazil in 2018, aiming to investigate CNS neuroinvasion in fatal YFV cases. YFV RNA was screened by RT-qPCR targeting the 3'UTR region of the YFV genome in CSF. CSF samples were tested for the presence of anti-YFV IgM and neutralizing antibodies, coupled with routine laboratory examinations. Among the 13 patients studied, we detected anti-YFV IgM in CSF from eight patients and YFV RNA in CSF from five patients. YFV RNA genomic load in CSF samples ranged from 1.75×103 to 5.42×103 RNA copies/mL. We genotyped YFV from three CSF samples that grouped with other YFV samples from the 2018 outbreak in Brazil within the South-American I genotype. Even though descriptions of neurologic manifestations due to wild type YFV (WT-YFV) infection are rare, since the last YF outbreak in Brazil in 2017-2018, a few studies have demonstrated WT-YFV RNA in CSF samples from YF fatal cases. Serological tests indicated the presence of IgM and neutralizing antibodies against YFV in CSF samples from two patients. Although the presence of viral RNA, IgM and neutralizing antibodies in CSF samples could indicate neuroinvasiveness, further studies are needed to better elucidate the role of YFV neuroinvasion and possible impacts in disease pathogenesis.

Thyroid autoimmunity and thyroid dysfunction in women with endometriosis

BACKGROUND

Women with endometriosis may have higher rates of autoimmune disorders, including hypothyroidism. The objective of this study was to compare the prevalence of thyroid dysfunction and autoimmune thyroid disease (AITD) between women with endometriosis and a control group.

METHODS

This was a cross-sectional study carried out in 148 women with surgically confirmed endometriosis and 158 controls. The mean age of the study group was 34.6 (7.1 SD) years (range 21-42) and 32.1 (7.7 SD) years (range 18-44) for controls. Serum levels of thyroid-stimulating hormone, free thyroxine and the anti-thyroperoxidase and anti-thyroglobulin antibodies were evaluated.

RESULTS

Thyroid disorders were identified in 20.9% of the endometriosis group and 26.5% of the control group (P = 0.25). The overall frequency of thyroid dysfunction was 12.2% and 10.8% for the endometriosis and control groups, and the frequency of positive thyroid antibodies, 14.9% and 22.2%, respectively (P = 0.20). Endometriosis stage and infertility history were not associated with thyroid dysfunction and AITD in the study group.

CONCLUSIONS

The prevalence of thyroid dysfunction and AITD was similar in the two study groups. Screening for thyroid disturbances in women with endometriosis is not indicated.

Time elapsed from onset of symptoms to diagnosis of endometriosis in a cohort study of Brazilian women

BACKGROUND

The study aim was to assess the time elapsed between onset of symptoms and diagnosis of endometriosis, and to identify the factors associated with diagnostic delay in a group of Brazilian women.

METHODS

In this retrospective cohort study, 200 women with surgically confirmed endometriosis were interviewed at an endometriosis outpatient clinic.

RESULTS

The median (interquartile range) time elapsed from onset of symptoms until diagnosis of endometriosis was 7.0 (range 3.5-12.1) years. The younger the women at onset of symptoms, the longer the period for diagnosis to be made: the median delay was 12.1 (range 8.0-17.2) years in women aged < or =19 years, and 3.3 (range 2.0-5.5) years in women aged > or =30 years. The median time period between onset of symptoms and diagnosis was 4.0 (2.0-6.0) years for women whose main complaint was infertility, but 7.4 (3.6-13.0) years for those with pelvic pain.

CONCLUSIONS

The delay in diagnosis of endometriosis was considered to be long, and especially so for young women with pelvic pain. More information relating to endometriosis should be offered to general physicians and gynaecologists in order to reduce the time taken to diagnose this condition.

Transseptal left heart catheterization for cardiac ablation procedures

Transseptal left heart catheterization has been performed as an alternative to the retrograde approach since 1958. However, this procedure can result in life-threatening complications, some of which may occur because of insufficient anatomical landmarks. Accordingly, we sought to assess the safety and efficacy of a new transseptal left heart catheterization technique designed for ablation procedures. Specifically, we examined whether electrode catheters could be used as anatomical landmarks, permitting identification of the aortic root and other critical structures.

RESULTS

One hundred and eight consecutive patients underwent transseptal left heart catheterization under biplane fluoroscopy during catheter ablation. Electrode catheters positioned in the right atrial appendage, His bundle region, and coronary sinus were used as anatomical landmarks to guide the transseptal unit to the fossa ovalis. The angles of the right anterior and left anterior oblique projections were selected in each patient based on the orientation of the His bundle and coronary sinus catheters. Transseptal left heart catheterization was successfully performed in all patients without complications. In contrast to previous reports, the direction of the needle at the successful puncture site in the last 96 patients varied substantially: 2 o'clock in 13 patients (13 %); 3 o'clock in 43 patients (45 %); and 4 o'clock in 40 patients (42 %).

CONCLUSION

The use of electrode catheters as anatomical landmarks and biplane fluoroscopy facilitates transseptal catheterization. This approach can be used safely during catheter ablation procedures.

A dimeric ArC2 compound from Peperomia pellucida

Pellucidin A, a novel dimeric ArC2 compound, together with dill-apiol have been isolated from the aerial parts of Peperomia pellucida. The structure of pellucidin A was established by 1D and 2D NMR spectroscopy (1H-1H COSY; 1H-13C COSY; DEPT; NOESY and double irradiation) and other spectroscopic techniques. The biogenesis of pellucidin A is also briefly discussed.

Pressure sores among malnourished necropsied adults--preliminary data

Pressure sores are common among bedridden, elderly, or malnourished patients, and may occur in terminal ill patients because of impaired mobility, fecal or urinary incontinence, and decreased healing capacity. The aim of this study was to compare frequency of pressure sores between malnourished and non-malnourished necropsied adults.

METHOD

All (n = 201) adults (age >/= 18 years) autopsied between 1986 and 1996 at the Teaching Hospital of Triangulo Mineiro Medical School (Uberaba) were eligible for the study. Gender, race, weight, height and main diagnoses were recorded. Ninety-six cases were excluded because of probable body water retention (congestive heart failure, hepatic insufficiency, nephrotic syndrome) or pressure sores secondary to peripheral vascular ischemia. Body mass index (BMI) was used to define malnourished (BMI < 18.5 kg/m2) and non-malnourished (BMI > 18.5kg/m2) groups.

RESULTS

Except for weight (42.5kg; range: 28-57 vs. 60; 36-134.5kg) and BMI (16.9; range: 12.4-18.5 vs. 22.7; range: 18.5-54.6kg/m2), respectively, there were no statistical differences among 43 malnourished and 62 non-malnourished cases in relation to age (54.9 +/- 20.4 vs. 52.9 +/- 17.9 years), percentage of white persons (74.4 vs. 64.5%), male gender (76.7 vs. 69.3%) and main diagnoses. Five malnourished (11. 6%) and 7 (11.5%) non-malnourished cases had pressure sores (p=0.89).

CONCLUSION

Pressure sores were equally common findings in necropsied persons with protein-energy malnutrition, as assessed by body mass index.

Flavonoids from Brosimum acutifolium

4'-Hydroxy-7,8-[2-(2-hydroxyisopropyl)dihydrofuran]flavan and 4',7-dihydroxy-8-(3,3-dimethylallyl)flavan, together with 10 known plant constituents, were obtained from the trunk bark of Brosimum acutifolium. Their structures were elucidated by spectroscopic methods, including 2D NMR spectroscopic techniques.

Dermatophytosis: association between ABO blood groups and reactivity to the trichophytin

The authors investigated the relationship between dermatophytosis and ABO blood groups through blood typing, identification of isolated dermatophytes and specific cellular immune response of 40 individuals carriers of this mycosis. They verified that the fungus Trichophyton rubrum, isolated from 54.5% of the patients, was more frequent in individuals belonging to blood group A. The cellular immune response, evaluated through the trichophytin antigen, was positive in 25% of the studied patients; the presence of immediate reactions (30 minutes) was verified in 35%. The blood group distribution among patients with dermatophytosis and control groups was, respectively: 47.5% X 36% in group A, 40% X 50% in group O, 12. 5% X 11% in group B. Even though the authors have found a higher number of patients belonging to blood group A infected by T. rubrum, these results suggest that there is no statistical evidence that these individuals are more susceptible to dermatophytosis.

Development and validation of an ECG algorithm for identifying accessory pathway ablation site in Wolff-Parkinson-White syndrome

INTRODUCTION

Delta wave morphology correlates with the site of ventricular insertion of accessory AV pathways. Because lesions due to radiofrequency (RF) current are small and well defined, it may allow precise localization of accessory pathways. The purpose of this study was to use RF catheter ablation to develop an ECG algorithm to predict accessory pathway location.

METHODS AND RESULTS

An algorithm was developed by correlating a resting 12-lead ECG with the successful RF ablation site in 135 consecutive patients with a single, anterogradely conducting accessory pathway (Retrospective phase). This algorithm was subsequently tested prospectively in 121 consecutive patients (Prospective phase). The ECG findings included the initial 20 msec of the delta wave in leads I, II, aVF, and V1 [classified as positive (+), negative (-), or isoelectric (+/-)] and the ratio of R and S wave amplitudes in leads III and V1 (classified as R > or = S or R < S). When tested prospectively, the ECG algorithm accurately localized the accessory pathway to 1 of 10 sites around the tricuspid and mitral annuli or at subepicardial locations within the venous system of the heart. Overall sensitivity was 90% and specificity was 99%. The algorithm was particularly useful in correctly localizing anteroseptal (sensitivity 75%, specificity 99%), and mid-septal (sensitivity 100%, specificity 98%) accessory pathways as well as pathways requiring ablation from within ventricular venous branches or anomalies of the coronary sinus (sensitivity 100%, specificity 100%).

CONCLUSION

A simple ECG algorithm identifies accessory pathway ablation site in Wolff-Parkinson-White syndrome. A truly negative delta wave in lead II predicts ablation within the coronary venous system.

Granulomatous reaction in the hamster cheek pouch induced by killed Paracoccidioides brasiliensis

We have studied the role of Paracoccidioides brasiliensis viability in the morphology of paracoccidioidomycotic granulomas in the hamster cheek pouch, an immunologically privileged site. Naive (N = 75) and previously sensitized (N = 50) two-month old male hamsters (Mesocricetus auratus) were inoculated into the pouch with 5 x 10(5) live or heat- or formalin-killed fungi. Previously sensitized animals presented a positive footpad test and immunodiffusion demonstrable antibodies (titer 1/32), at the time of sacrifice; naive animals were always negative for those immunological tests. The histological results showed that, like viable P. brasiliensis, killed fungi evoke typical epithelioid granulomas in 100% of animals, even in the absence of immunodiffusion or footpad test detectable immune response. The granulomas elicited by killed fungi were devoid of giant cells or a mononuclear cell halo, suggesting that live proliferating fungi or their products may be involved in these events.

Experimental paracoccidioidomycosis of hamster inoculated in the cheek pouch

We compared the granuloma morphology and immune response of hamsters inoculated with Paracoccidioides brasiliensis (Pb) into the cheek pouch, which lacks lymphatic drainage, and into the footpad, which is rich in lymphatics. Our objective was to better understand the modulation of Pb granuloma in an immunocompetent animal inoculated in an immunologically privileged site. The humoral immune response (ELISA) and cell mediated immunity (footpad test) became positive on days 7 and 14, respectively in animals inoculated into footpad and on days 35 and 60 in animals inoculated into the pouch. Typical epithelioid granulomas were observed at both sites on day 14. The number of fungi gradually decreased from the beginning of the experiment in footpad lesions, but only after day 35 in pouch granulomas, when cell mediated immunity was detectable. The results indicate that typical epithelioid paracoccidioidomycotic granulomas may develop in the absence of a detectable immune response; however, they are incapable of controlling fungal reproduction. Lack of lymphatic drainage delays the appearance of a detectable immune response, but with time fungi escape from the pouch, elicit an immune response and reach other organs. Our results further indicate the importance of the lymphatics in the pathogenesis of paracoccidioidomycosis.

[Developmental aspects of the Rubino reaction]

The Rubino reaction was studied in 178 leprosy patients to correlate its positivity, clinical form, E.N.L., and time and activity of the disease. The patients studied were classified according to the criteria established by the 1953 Madrid Congress. The results show that the tuberculoid patients presented negative Rubino reactions regardless of any of the parameters studied. The borderline patients showed 9% positive Rubino reaction not related to any of the observed parameters studied. The lepromatous patients showed a significant difference of positivity to the Rubino reaction when grouped as to the disease's active or non-active presence. Active lepromatous patients showed 55% of positivity to the Rubino reaction whereas patients considered clinically inactive showed only 6% of positivity. The fact that the Rubino reaction is negative in the majority of patients who are clinically cured would indicate that this test could be included as part of the criteria used in determining which clinically cured lepromatous patients can discontinue medication without risking a relapse.