Cohort profile: follow-up of a household cohort throughout five epidemic waves of SARS-CoV-2 in Rio de Janeiro, Brazil.

Since May 2020, we have been conducting a comprehensive study to understand the natural history of SARS-CoV-2 infection in Rio de Janeiro, Brazil. Our focus has been on following families, systematically collecting respiratory tract swabs and blood samples, monitoring symptoms, and gathering data on vaccine status. This paper aims to describe the household cohort across five epidemic waves of SARS-CoV-2, providing an overview of the collected data and a description of the epidemiological, clinical, and immunological characteristics and incidence of SARS-CoV-2 infection. Our cohort includes 691 participants from 189 households. During the five epidemic waves, we detected 606 infections. The incidence density of SARS-CoV-2 infection ranged from 4 (Delta) to 56 (B.1.1.33) per 1,000 person-week, with a peak in wave B.1.1.33 in all age groups. The seroprevalence of SARS-CoV-2 antibodies (IgG anti spike protein) varied from 37%, in the pre-VoC period, to 99%, in the Omicron period, progressively increasing after each wave in a similar manner regardless of age. As we have monitored the cohort continuously since the beginning of the pandemic, we were able to collect data across different scenarios according to the predominant lineage in circulation. Via active monitoring of families, we were able to carry out an epidemiological surveillance on SARS-CoV-2, including its variants, persistence of symptoms, and changes in immunity over time in the population, contributing to knowledge of the natural history of SARS-CoV-2 infection.

Viral shedding of SARS-CoV-2 in body fluids associated with sexual activity: a systematic review and meta-analysis.

OBJECTIVE: To identify and summarise the evidence on the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA detection and persistence in body fluids associated with sexual activity (saliva, semen, vaginal secretion, urine and faeces/rectal secretion). ELIGIBILITY: All studies that reported detection of SARS-CoV-2 in saliva, semen, vaginal secretion, urine and faeces/rectal swabs. INFORMATION SOURCES: The WHO COVID-19 database from inception to 20 April 2022. RISK OF BIAS ASSESSMENT: The National Institutes of Health tools. SYNTHESIS OF RESULTS: The proportion of patients with positive results for SARS-CoV-2 and the proportion of patients with a viral duration/persistence of at least 14 days in each fluid was calculated using fixed or random effects models. INCLUDED STUDIES: A total of 182 studies with 10 023 participants. RESULTS: The combined proportion of individuals with detection of SARS-CoV-2 was 82.6% (95% CI: 68.8% to 91.0%) in saliva, 1.6% (95% CI: 0.9% to 2.6%) in semen, 2.7% (95% CI: 1.8% to 4.0%) in vaginal secretion, 3.8% (95% CI: 1.9% to 7.6%) in urine and 31.8% (95% CI: 26.4% to 37.7%) in faeces/rectal swabs. The maximum viral persistence for faeces/rectal secretions was 210 days, followed by semen 121 days, saliva 112 days, urine 77 days and vaginal secretions 13 days. Culturable SARS-CoV-2 was positive for saliva and faeces. LIMITATIONS: Scarcity of longitudinal studies with follow-up until negative results. INTERPRETATION: SARS-CoV-2 RNA was detected in all fluids associated with sexual activity but was rare in semen and vaginal secretions. Ongoing droplet precautions and awareness of the potential risk of contact with faecal matter/rectal mucosa are needed. PROSPERO REGISTRATION NUMBER: CRD42020204741.

Evidence of Zika Virus Reinfection by Genome Diversity and Antibody Response Analysis, Brazil.

We generated 238 Zika virus (ZIKV) genomes from 135 persons in Brazil who had samples collected over 1 year to evaluate virus persistence. Phylogenetic inference clustered the genomes together with previously reported ZIKV strains from northern Brazil, showing that ZIKV has been remained relatively stable over time. Temporal phylogenetic analysis revealed limited within-host diversity among most ZIKV-persistent infected associated samples. However, we detected unusual virus temporal diversity from >5 persons, uncovering the existence of divergent genomes within the same patient. All those patients showed an increase in neutralizing antibody levels, followed by a decline at the convalescent phase of ZIKV infection. Of interest, in 3 of those patients, titers of neutralizing antibodies increased again after 6 months of ZIKV infection, concomitantly with real-time reverse transcription PCR re-positivity, supporting ZIKV reinfection events. Altogether, our findings provide evidence for the existence of ZIKV reinfection events.

Cohort profile: follow-up of a household cohort throughout five epidemic waves of SARS-CoV-2 in Rio de Janeiro, Brazil / Perfil da coorte: acompanhamento de uma coorte domiciliar ao longo de cinco ondas epidêmicas de SARS-CoV-2 no Rio de Janeiro, Brasil / Perfil de la cohorte: seguimiento de una cohorte de hogares durante cinco olas epidémicas de SARS-CoV-2 en Río de Janeiro, Brasil

Abstract: Since May 2020, we have been conducting a comprehensive study to understand the natural history of SARS-CoV-2 infection in Rio de Janeiro, Brazil. Our focus has been on following families, systematically collecting respiratory tract swabs and blood samples, monitoring symptoms, and gathering data on vaccine status. This paper aims to describe the household cohort across five epidemic waves of SARS-CoV-2, providing an overview of the collected data and a description of the epidemiological, clinical, and immunological characteristics and incidence of SARS-CoV-2 infection. Our cohort includes 691 participants from 189 households. During the five epidemic waves, we detected 606 infections. The incidence density of SARS-CoV-2 infection ranged from 4 (Delta) to 56 (B.1.1.33) per 1,000 person-week, with a peak in wave B.1.1.33 in all age groups. The seroprevalence of SARS-CoV-2 antibodies (IgG anti spike protein) varied from 37%, in the pre-VoC period, to 99%, in the Omicron period, progressively increasing after each wave in a similar manner regardless of age. As we have monitored the cohort continuously since the beginning of the pandemic, we were able to collect data across different scenarios according to the predominant lineage in circulation. Via active monitoring of families, we were able to carry out an epidemiological surveillance on SARS-CoV-2, including its variants, persistence of symptoms, and changes in immunity over time in the population, contributing to knowledge of the natural history of SARS-CoV-2 infection.

Resumo: Desde maio de 2020, temos conduzido um estudo abrangente para entender a história natural da infecção por SARS-CoV-2 no Rio de Janeiro, Brasil. Nosso foco tem sido acompanhar as famílias das quais coletamos sistematicamente amostras de sangue e do trato respiratório, monitoramos os sintomas e reunimos dados sobre o status de vacinação. Este artigo tem como objetivo descrever a coorte de domicílios ao longo de cinco ondas epidêmicas de SARS-CoV-2, fornecendo uma visão geral dos dados coletados e uma descrição das características epidemiológicas, clínicas e imunológicas e da incidência da infecção por SARS-CoV-2. Nossa coorte inclui 691 participantes de 189 domicílios. Ao longo das cinco ondas epidêmicas, detectamos 606 infecções. A densidade de incidência da infecção por SARS-CoV-2 variou de 4 (Delta) a 56 (B.1.1.33) a cada 1.000 pessoas por semana e foi mais alta na onda B.1.1.33 em todas as faixas etárias. A soroprevalência de anticorpos contra o SARS-CoV-2 (proteína IgG anti-spike) variou de 37% no período pré-VoC a 99% no período Omicron e aumentou onda após onda de maneira semelhante, independentemente da idade dos participantes. Como monitoramos a coorte continuamente desde o início da pandemia, pudemos coletar dados em diferentes cenários, de acordo com a cepa predominante em circulação. Por meio do monitoramento ativo das famílias, conseguimos conduzir uma vigilância epidemiológica do SARS-CoV-2, de suas variantes, da persistência dos sintomas e das mudanças na imunidade da população ao longo do tempo, contribuindo para o conhecimento da história natural da infecção pelo SARS-CoV-2.

Resumen: Desde mayo de 2020 se realiza un estudio exhaustivo con el fin de estimar el curso natural de la infección por SARS-CoV-2 en Río de Janeiro, Brasil. Se aplica un seguimiento a las familias en el cual se recolectan sistemáticamente muestras de sangre y de las vías respiratorias, se controlan los síntomas y se recogen datos sobre el estado de vacunación. Este artículo tiene como objetivo describir la cohorte de hogares durante cinco olas epidémicas de SARS-CoV-2, y proporcionar una visión general de los datos recopilados y una descripción de las características epidemiológicas, clínicas e inmunológicas, y de la incidencia de la infección por SARS-CoV-2. La cohorte incluyó a 691 participantes de 189 hogares. A lo largo de las cinco olas epidémicas, se detectaron 606 infecciones. La densidad de incidencia de la infección por SARS-CoV-2 varió de 4 (Delta) a 56 (B.1.1.33) por cada 1.000 personas por semana, y fue más alta en la ola B.1.1.33 en todos los grupos de edad. La seroprevalencia de anticuerpos contra el SARS-CoV-2 (proteína IgG antipico) varió del 37% en el período anti-VOC al 99% en el período Ómicron y aumentó ola tras ola de manera similar, independientemente de la edad de los participantes. El monitoreo continuo de la cohorte desde el comienzo de la pandemia permitió recopilar datos en diferentes escenarios según la cepa predominante en circulación. A partir del monitoreo activo de las familias, se realizó una vigilancia epidemiológica del SARS-CoV-2, sus variantes, la persistencia de los síntomas y los cambios en la inmunidad de la población a lo largo del tiempo, contribuyendo al conocimiento del curso natural de la infección por SARS-CoV-2.

Detection and persistence of Zika virus in body fluids and associated factors: a prospective cohort study.

This study aimed to analyze the detection and duration of the Zika virus (ZIKV) in plasma, urine, saliva, sweat, rectal swabs, vaginal secretions, breast milk, and semen and to explore risk factors associated with prolonged viral persistence. A prospective cohort study of symptomatic patients and their household contacts was conducted in Brazil from July 2017 to June 2019. A total of 260 individuals (184 women and 76 men) with confirmed ZIKV infection were enrolled and followed up for 12 months. ZIKV RNA was present in all body fluid specimens and detectable for extended periods in urine, sweat, rectal swabs, and semen. The longest detection duration was found in semen, with high viral loads in the specimens. ZIKV RNA clearance was associated with several factors, including age, sex, education level, body mass index, non-purulent conjunctivitis, joint pain, and whether the participant had a history of yellow fever vaccination. The influence of each of these factors on the low or fast viral clearance varied according to the specific body fluid under investigation. Recurrent ZIKV detection events after total viral clearance were observed in the cohort. Our findings provide valuable insights into the persistence and potential recurrence of ZIKV infection, highlighting the need for continued monitoring and follow-up of individuals infected with ZIKV and for effective prevention measures to reduce the risk of transmission.

Long COVID-19 syndrome associated with Omicron XBB.1.5 infection: a case report.

BACKGROUND: There is interest in lingering non-specific symptoms after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, referred to as Long coronavirus disease 2019 (Long COVID-19). It remains unknown whether the risk of Long COVID-19 is associated with pre-existing comorbidities or initial COVID-19 severity, including infections due to new Omicron lineages which predominated in 2023. OBJECTIVES: The aim of this case report was to characterize the clinical features of acute XBB.1.5 infection followed by Long COVID-19. METHODS: We followed a 73-year old female resident of Rio de Janeiro with laboratory-confirmed SARS-CoV-2 during acute infection and subsequent months. The SARS-CoV-2 lineage was determined by genome sequencing. FINDINGS: The participant denied comorbidities and had completed a two-dose vaccination schedule followed by two booster doses eight months prior to SARS-CoV-2 infection. Primary infection by viral lineage XBB.1.5. was clinically mild, but the participant subsequently reported persistent fatigue. MAIN CONCLUSIONS: This case demonstrates that Long COVID-19 may develop even after mild disease due to SARS-CoV-2 in fully vaccinated and boosted individuals without comorbidities. Continued monitoring of new SARS-CoV-2 lineages and associated clinical outcomes is warranted. Measures to prevent infection should continue to be implemented including development of new vaccines and antivirals effective against novel variants.

Paracoccidioidomycosis and pregnancy: A 40-year single-center cohort study in the endemic area of Rio de Janeiro, Brazil.

The occurrence of acute paracoccidioidomycosis (PCM) in urban areas of the Rio de Janeiro state, Brazil, has emerged in recent years. Therefore, young populations, including pregnant women, are at a higher risk of infection. Furthermore, young women undergoing itraconazole treatment for PCM have increased chances to get pregnant because this medication may reduce the effectiveness of contraceptives. Acute PCM is invasive, reaching abdominal organs, posing a maternal-fetal risk. PCM treatment in pregnant women is also challenging due to the teratogenicity associated with the currently available oral drugs. There are scarce studies on PCM and pregnancy, mainly consisting of case reports and experimental murine models that highlight the severity of this association. We conducted a database research at a PCM reference center in Rio de Janeiro state from 1980 to 2020. We included patients diagnosed with PCM who were pregnant shortly before, at admission, or at any moment of their PCM follow-up care. Data related to pregnancy, childbirth, and the newborn were obtained from the Brazilian official public databases. We also reviewed the epidemiological and clinical features of these patients. During the study period, we identified 18 pregnant patients, with a median age of 26 years (range: 16-38). Among these cases, six (33.3%) were detected in the last 5 years, and 14 (77.8%) presented acute PCM, supporting the recent shift in the epidemiological profile towards acute PCM. Most pregnancies occurred during PCM treatment (n = 11, 61.1%), which led to challenges in the therapeutic management. Maternal-fetal complications occurred in some of these cases, including vaginal bleeding (n = 1), preeclampsia (n = 1), prematurity (n = 2), low birth weight (n = 4), and fetal deaths (n = 2). PCM during pregnancy presents a significant public health concern in the context of the emergence of acute PCM in urban areas.

Oral manifestations of COVID-19 in unvaccinated patients: a cross-sectional study.

BACKGROUND: Early studies have highlighted the possible development of dysgeusia and anosmia in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and these manifestations should be considered a potential indication of coronavirus disease 19 (COVID-19). As potential contributors to these symptoms, dentists should perform careful oral and oropharyngeal examinations and document suspicious oral lesions in patients with COVID-19, especially in those who complain of loss of taste and smell. The study's objective was to assess the prevalence of oral manifestations among ambulatory unvaccinated symptomatic patients with suspected COVID-19 during the acute phase of the disease. METHODS: This cross-sectional study evaluated oral manifestations in adults (aged ≥ 18 years) with suspected and confirmed SARS-CoV-2 infection. Chi-square and Fisher's exact tests were used to compare data between the groups (rRT-PCR-positive and rRT-PCR-negative patients). RESULTS: One hundred thirty-six participants were included. Most were female (n = 79; 58.1%), with a mean age of 39.53 (± 14.17) years. Of these, 54 (39.7%) had a positive rRT-PCR test, and 82 (60.3%) had negative rRT-PCR results. Oral manifestations were observed in 40 participants (74.1%) in the rRT-PCR-positive group and 67 participants (81.7%) in the rRT-PCR-negative group. The most common oral manifestations were xerostomia (n = 85; 62.5%) and dysgeusia/ageusia (n = 57; 41.9%). Different rates of gingivitis (n = 12; 22.2% vs. n = 5; 6.1%; p = 0.005) and halitosis (n = 7; 13.0% vs. n = 1; 1.2%; p = 0.007) were observed between the rRT-PCR-positive and -negative groups, respectively. Mouth ulcers, glossitis, tongue coating, and petechiae were reported in both groups without significant differences. CONCLUSIONS: A high prevalence of oral manifestations was observed in symptomatic patients with suspected or confirmed COVID-19. CLINICAL RELEVANCE: This study highlights the importance of routine oral examinations by dentists as part of the multidisciplinary care of COVID-19 patients.

Zika-specific neutralizing antibodies targeting inter-dimer envelope epitopes.

Zika virus (ZIKV) is an emerging pathogen that causes devastating congenital defects. The overlapping epidemiology and immunologic cross-reactivity between ZIKV and dengue virus (DENV) pose complex challenges to vaccine design, given the potential for antibody-dependent enhancement of disease. Therefore, classification of ZIKV-specific antibody targets is of notable value. From a ZIKV-infected rhesus macaque, we identify ZIKV-reactive B cells and isolate potent neutralizing monoclonal antibodies (mAbs) with no cross-reactivity to DENV. We group these mAbs into four distinct antigenic groups targeting ZIKV-specific cross-protomer epitopes on the envelope glycoprotein. Co-crystal structures of representative mAbs in complex with ZIKV envelope glycoprotein reveal envelope-dimer epitope and unique dimer-dimer epitope targeting. All four specificities are serologically identified in convalescent humans following ZIKV infection, and representative mAbs from all four groups protect against ZIKV replication in mice. These results provide key insights into ZIKV-specific antigenicity and have implications for ZIKV vaccine, diagnostic, and therapeutic development.

Challenges of acute febrile illness diagnosis in a national infectious diseases center in Rio de Janeiro: 16-year experience of syndromic surveillance.

INTRODUCTION: Acute febrile illnesses (AFI) are a frequent chief complaint in outpatients. Because the capacity to investigate the causative pathogen of AFIs is limited in low- and middle-income countries, patient management may be suboptimal. Understanding the distribution of causes of AFI can improve patient outcomes. This study aims to describe the most common etiologies diagnosed over a 16-years period in a national reference center for tropical diseases in a large urban center in Rio de Janeiro, Brazil. METHODS: From August 2004-December 2019, 3591 patients > 12 years old, with AFI and/or rash were eligible. Complementary exams for etiological investigation were requested using syndromic classification as a decision guide. Results. Among the 3591 patients included, endemic arboviruses such as chikungunya (21%), dengue (15%) and zika (6%) were the most common laboratory-confirmed diagnosis, together with travel-related malaria (11%). Clinical presumptive diagnosis lacked sensitivity for emerging diseases such as zika (31%). Rickettsia disease and leptospirosis were rarely investigated and an infrequent finding when based purely on clinical features. Respiratory symptoms increased the odds for the diagnostic remaining inconclusive. CONCLUSIONS: Numerous patients did not have a conclusive etiologic diagnosis. Since syndromic classification used for standardization of etiological investigation and presumptive clinical diagnosis had moderate accuracy, it is necessary to incorporate new diagnostic technologies to improve diagnostic accuracy and surveillance capacity.

Long COVID-19 syndrome associated with Omicron XBB.1.5 infection: a case report

BACKGROUND There is interest in lingering non-specific symptoms after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, referred to as Long coronavirus disease 2019 (Long COVID-19). It remains unknown whether the risk of Long COVID-19 is associated with pre-existing comorbidities or initial COVID-19 severity, including infections due to new Omicron lineages which predominated in 2023. OBJECTIVES The aim of this case report was to characterize the clinical features of acute XBB.1.5 infection followed by Long COVID-19. METHODS We followed a 73-year old female resident of Rio de Janeiro with laboratory-confirmed SARS-CoV-2 during acute infection and subsequent months. The SARS-CoV-2 lineage was determined by genome sequencing. FINDINGS The participant denied comorbidities and had completed a two-dose vaccination schedule followed by two booster doses eight months prior to SARS-CoV-2 infection. Primary infection by viral lineage XBB.1.5. was clinically mild, but the participant subsequently reported persistent fatigue. MAIN CONCLUSIONS This case demonstrates that Long COVID-19 may develop even after mild disease due to SARS-CoV-2 in fully vaccinated and boosted individuals without comorbidities. Continued monitoring of new SARS-CoV-2 lineages and associated clinical outcomes is warranted. Measures to prevent infection should continue to be implemented including development of new vaccines and antivirals effective against novel variants.

Fatal Brazilian spotted fever in a healthy military man during field training in Rio de Janeiro city, southeastern Brazil.

Brazilian spotted fever, a zoonotic disease transmitted by ticks, is caused by Rickettsia rickettsii. We report a fulminant case of this zoonosis in a healthy 46-year-old military man in the urban region of Rio de Janeiro city, in October, 2021. Ticks and capybaras (Amblyomma sculptum, Hydrochoerus hydrochaeris, respectively) were identified in the military fields, pointing to the participation of this large synanthropic rodent, recognized as an efficient amplifier host of Rickettsia rickettsii in Brazil. As the military population is considered a risk group for spotted fever, it is necessary to alert health professionals to the importance of the early detection of the disease and its adequate management, mainly in populations that are particularly at risk of exposure to ticks, in order to avoid fatal outcomes.

Beyond arboviruses: A multicenter study to evaluate differential diagnosis of rash diseases and acute febrile illness cases in Rio de Janeiro, Brazil.

INTRODUCTION: A wide variety of viruses can cause rash diseases (RDs) or acute febrile illness (AFIs) in children, adolescents and adults; however, approximately 19% of RD cases and 40% of AFI cases remain without a defined etiology. Parvovirus B19 (B19V) and herpesvirus infection can also cause RD and/or AFI, and in some risk groups, these infections can become persistent (or latent) and may require hospital treatment. Since these infections do not have mandatory reporting, they can be hidden by other diseases, such as those caused by arboviruses (e.g., dengue virus). In this context, the aim of this study was to pursue the differential laboratory diagnoses of B19V and herpesvirus infections in patients with RD and AFI, without a defined etiology, seen in hospitals and/or reference centers for infectious diseases in Rio de Janeiro. METHODS: A total of 114 participants were enrolled in the study, including 54 children and 60 adults. B19V infection was assessed by real-time PCR (qPCR) and ELISA (anti-B19V IgM and IgG). EBV was assessed through qPCR, and betaherpesviruses (HCMV, HHV-6 and HHV-7) were assessed through multiplex qPCR. Sociodemographic and clinical data were obtained from the medical record data of these participants. RESULTS: The median age of children with RD was 2 years (interquartile range (IQR): 5), and 55.6% were male. Among adults with AFI, the median age was 38 years (IQR: 21), and 56.7% were female. Regarding RD patients, viral prevalence (and load) were 5.5%(104IU/mL), 3.4%(104IU/mL), 5.5%(104IU/mL) and 11.1%(105IU/mL) for B19V, EBV, HCMV and HHV-6 infection, respectively, and in AFI patients they were 6.6%(105IU/mL), 1.6%(103IU/mL), 3.3%(104IU/mL) for B19V, HCMV and HHV-6, respectively. HHV-7 was not detected in RD or AFI patients. CONCLUSION: These results suggest the importance of including B19V and herpesviruses in the differential laboratory diagnoses for patients with RD and AFI, not only for epidemiological purposes but also for the proper management of the patient.

Myopericarditis associated with acute Zika virus infection: a case report.

BACKGROUND: Zika virus infection is commonly described as a mild and self-limiting illness. However, cardiac complications were associated with acute Zika virus infection. CASE PRESENTATION: A 46-year-old woman without previous comorbidities with a 1-day history of symptoms tested positive for ZIKV by real time reverse transcriptase polymerase chain reaction (rRT-PCR). She was admitted two days after with clinical worsening, cardiac enzymes elevated, and cardiac imaging findings, and the diagnosis of myopericarditis was made. The patient was treated and presented significant clinical improvement after one year. CONCLUSIONS: Cardiac complication following ZIKV infection appears to be infrequent. Here, we report a rare case of viral myopericarditis caused by ZIKV infection.

Cohort-profile: Household transmission of SARS-CoV-2 in a low-resource community in Rio de Janeiro, Brazil.

PURPOSE: To better understand the household transmission of SARS-COV-2 in a low-resource community in Rio de Janeiro during the COVID-19 pandemic (2020-2022). PARTICIPANTS: This is an open prospective cohort study of children ≤12 years old and their household contacts. During home visits over 24 months, we collected data on sociodemographic characteristics, behavioural data, clinical manifestations of SARS-CoV-2, vaccination status, SARS-CoV-2 (reverse transcription-polymerase chain reaction) RT-PCR and anti-S antibody tests. Among adults, the majority of participants were women (62%). FINDINGS TO DATE: We enrolled 845 families from May 2020 to May 2022. The median number of residents per household was four. The median household density, defined as the number of persons per room, was 0.95. The risk of SARS-CoV-2 occurrence was higher in households with a high number of persons per room. Children were not the principal source of SARS-CoV-2 infections in their households during the first wave of the pandemic. FUTURE PLANS: Future studies will investigate cellular and humoral immune responses to locally circulating SARS-CoV-2 variants, which is relevant for the design of vaccines, antivirals and monoclonal antibodies. We will also engage in outreach to encourage vaccination as a means of limiting the transmission of novel SARS-CoV-2 variants and other emerging pathogens.

Fatal Brazilian spotted fever in a healthy military man during field training in Rio de Janeiro city, southeastern Brazil

ABSTRACT Brazilian spotted fever, a zoonotic disease transmitted by ticks, is caused by Rickettsia rickettsii. We report a fulminant case of this zoonosis in a healthy 46-year-old military man in the urban region of Rio de Janeiro city, in October, 2021. Ticks and capybaras (Amblyomma sculptum, Hydrochoerus hydrochaeris, respectively) were identified in the military fields, pointing to the participation of this large synanthropic rodent, recognized as an efficient amplifier host of Rickettsia rickettsii in Brazil. As the military population is considered a risk group for spotted fever, it is necessary to alert health professionals to the importance of the early detection of the disease and its adequate management, mainly in populations that are particularly at risk of exposure to ticks, in order to avoid fatal outcomes.

Chikungunya associated vulvitis: case report and literature review / Vulvite associada a Chikungunya: relato de caso e revisão de literatura

Introduction: Chikungunya virus is spreading worldwide due to migration and globalization and could be presented with systemic and with unusual symptoms. Objective: To report a case of virus-transmitted infection detected in a woman during the gynecological examination at a vulvar clinic. Case report: A 73-year-old Caucasian woman attended a vulvar clinic because of dyspareunia and vulvar burning. Ulcers were observed on labia minora and perineum. A Chikungunya was diagnosed by seroconversion in paired specimens. She was prescribed prednisolone 40 mg once a day for 10 days. After oral steroid treatment, the woman had no body rashes or lesions on her genitals. Conclusion: This study emphasized that rare signs of unusual vulvitis with ulcers could be associated with Chikungunya infection.

Introdução: O vírus Chikungunya está se espalhando pelo mundo por conta da migração e da globalização, podendo apresentar sintomas sistêmicos e incomuns. Objetivo: Relatar um caso de infecção pelo vírus detectado em uma mulher por ocasião do exame ginecológico em clínica de patologia vulvar. Relato do caso: Uma mulher caucasiana de 73 anos foi a uma clínica vulvar por causa de dispareunia e queimação vulvar. Úlceras foram observadas nos pequenos lábios e no períneo. O diagnóstico de Chikungunya foi realizado por soroconversão em espécimes pareados. Foi prescrita prednisolona 40 mg uma vez ao dia por dez dias. Após o tratamento com esteróides orais, a mulher não apresentou erupções ou lesões nos órgãos genitais. Conclusão: Este estudo enfatizou que quadros raros de vulvite com úlcera podem estar associados à infecção por Chikungunya.

Diagnostic performance of anti-Zika virus IgM, IgAM and IgG ELISAs during co-circulation of Zika, dengue, and chikungunya viruses in Brazil and Venezuela.

BACKGROUND: Serological diagnosis of Zika virus (ZIKV) infection is challenging because of the antibody cross-reactivity among flaviviruses. At the same time, the role of Nucleic Acid Testing (NAT) is limited by the low proportion of symptomatic infections and the low average viral load. Here, we compared the diagnostic performance of commercially available IgM, IgAM, and IgG ELISAs in sequential samples during the ZIKV and chikungunya (CHIKV) epidemics and co-circulation of dengue virus (DENV) in Brazil and Venezuela. METHODOLOGY/PRINCIPAL FINDINGS: Acute (day of illness 1-5) and follow-up (day of illness ≥ 6) blood samples were collected from nine hundred and seven symptomatic patients enrolled in a prospective multicenter study between June 2012 and August 2016. Acute samples were tested by RT-PCR for ZIKV, DENV, and CHIKV. Acute and follow-up samples were tested for IgM, IgAM, and IgG antibodies to ZIKV using commercially available ELISAs. Among follow-up samples with a RT-PCR confirmed ZIKV infection, anti-ZIKV IgAM sensitivity was 93.5% (43/46), while IgM and IgG exhibited sensitivities of 30.3% (10/33) and 72% (18/25), respectively. An additional 24% (26/109) of ZIKV infections were detected via IgAM seroconversion in ZIKV/DENV/CHIKV RT-PCR negative patients. The specificity of anti-ZIKV IgM was estimated at 93% and that of IgAM at 85%. CONCLUSIONS/SIGNIFICANCE: Our findings exemplify the challenges of the assessment of test performance for ZIKV serological tests in the real-world setting, during co-circulation of DENV, ZIKV, and CHIKV. However, we can also demonstrate that the IgAM immunoassay exhibits superior sensitivity to detect ZIKV RT-PCR confirmed infections compared to IgG and IgM immunoassays. The IgAM assay also proves to be promising for detection of anti-ZIKV seroconversions in sequential samples, both in ZIKV PCR-positive as well as PCR-negative patients, making this a candidate assay for serological monitoring of pregnant women in future ZIKV outbreaks.

Investigation of SARS-CoV-2 infection in dogs and cats of humans diagnosed with COVID-19 in Rio de Janeiro, Brazil.

BACKGROUND: Infection by SARS-CoV-2 in domestic animals has been related to close contact with humans diagnosed with COVID-19. Objectives: To assess the exposure, infection, and persistence by SARS-CoV-2 of dogs and cats living in the same households of humans that tested positive for SARS-CoV-2, and to investigate clinical and laboratory alterations associated with animal infection. METHODS: Animals living with COVID-19 patients were longitudinally followed and had nasopharyngeal/oropharyngeal and rectal swabs collected and tested for SARS-CoV-2. Additionally, blood samples were collected for laboratory analysis, and plaque reduction neutralization test (PRNT90) to investigate specific SARS-CoV-2 antibodies. RESULTS: Between May and October 2020, 39 pets (29 dogs and 10 cats) of 21 patients were investigated. Nine dogs (31%) and four cats (40%) from 10 (47.6%) households were infected with or seropositive for SARS-CoV-2. Animals tested positive from 11 to 51 days after the human index COVID-19 case onset of symptoms. Three dogs tested positive twice within 14, 30, and 31 days apart. SARS-CoV-2 neutralizing antibodies were detected in one dog (3.4%) and two cats (20%). In this study, six out of thirteen animals either infected with or seropositive for SARS-CoV-2 have developed mild but reversible signs of the disease. Using logistic regression analysis, neutering, and sharing bed with the ill owner were associated with pet infection. CONCLUSIONS: The presence and persistence of SARS-CoV-2 infection have been identified in dogs and cats from households with human COVID-19 cases in Rio de Janeiro, Brazil. People with COVID-19 should avoid close contact with their pets during the time of their illness.