Optimisation of a quantitative polymerase chain reaction-based strategy for the detection and quantification of human herpesvirus 6 DNA in patients undergoing allogeneic haematopoietic stem cell transplantation.

Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and early diagnosis of related clinical diseases, constitute essential measures to improve outcomes. A prospective survey on the incidence and clinical features of HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the impact of this infection on HSCT outcome remains unclear. A rapid test based on real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen and quantify clinical samples for HHV-6. The detection step was based on reaction with TaqMan® hydrolysis probes. A set of previously described primers and probes have been tested to evaluate efficiency, sensitivity and reproducibility. The target efficiency range was 91.4% with linearity ranging from 10-106 copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of plasma. The qPCR assay developed in the present study was simple, rapid and sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this test may be useful as a practical tool to help elucidate the clinical relevance of HHV-6 infection and reactivation in different scenarios and to determine the need for surveillance.

[Relationship between air temperature and dengue incidence: time series study in Minas Gerais, Brazil (2010-2019)]. / Relação entre temperatura do ar e incidência de dengue: estudo de séries temporais em Minas Gerais, Brasil (2010-2019).

Air temperature is a climatic factor that affects the incidence of dengue, with effects varying according to time and space. We investigated the relationship between minimum air temperature and dengue incidence in Minas Gerais, Brazil, and evaluated the influence of socioeconomic and geographic variables on this relationship. This is a time series study with analysis conducted in three distinct stages: modeling using a distributed lag non-linear model, meta-analysis of models obtained, and meta-regression with geographic and socioeconomic data. Minimum temperature was a protective factor at extreme cold temperatures (RR = 0.65; 95%CI: 0.56-0.76) and moderate cold temperatures (RR = 0.71; 95%CI: 0.64-0.79), and a risk factor at moderate hot temperatures (RR = 1.15; 95%CI: 1.07-1.24), but not at extreme hot temperatures (RR = 1.1; 95%CI: 0.99-1.22). Heterogeneity of the models was high (I2 = 60%), which was also observed in meta-regression. Moderate and extreme cold temperatures have a protective effect, while moderate hot temperatures increase the risk. However, minimum air temperature does not explain the variability in the region, not even with the other variables in meta-regression.

A temperatura do ar é um fator climático que afeta a incidência da dengue, com efeitos variando conforme o tempo e o espaço. Investigamos a relação entre a temperatura mínima do ar e a incidência da doença em Minas Gerais, Brasil, e avaliamos a influência de variáveis socioeconômicas e geográficas nessa relação, calculando-se o risco relativo (RR). Este é um estudo de série temporal com análise conduzida em três etapas distintas: modelagem por uso de distributed lag non-linear model (modelos não-lineares distributivos com defasagem), metanálise dos modelos obtidos e metarregressão com dados geográficos e socioeconômicos. A temperatura mínima foi um fator de proteção quando em temperaturas frias extremas (RR = 0,65; IC95%: 0,56-0,76) e moderadas (RR = 0,71; IC95%: 0,64-0,79) e fator de risco em temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), mas não em extremo (RR = 1,1; IC95%: 0,99-1,22). A heterogeneidade dos modelos foi elevada (I2 = 60%) e essa medida não foi alterada em metarregressão. Temperaturas frias moderadas e extremas causam efeito protetivo, enquanto moderadas quentes aumentam o risco. No entanto, a temperatura mínima do ar não explica nem a variabilidade da região, nem mesmo com as outras variáveis em metarregressão.

La temperatura del aire es un factor climático que afecta la incidencia del dengue, con efectos que varían según el tiempo y el territorio. Investigamos la relación entre la temperatura mínima del aire y la incidencia de la enfermedad en Minas Gerais, Brasil, y evaluamos la influencia de variables socioeconómicas y geográficas en esta relación. Se trata de un estudio de serie temporal cuyo análisis se realiza en tres etapas distintas: modelación mediante el uso de distributed lag non-linear model (modelos distributivos no lineales con retraso), metaanálisis de los modelos obtenidos y metarregresión con datos geográficos y socioeconómicos. La temperatura mínima fue un factor de protección ante temperaturas extremadamente frías (RR = 0,65; IC95%: 0,56-0,76) y moderadas (RR = 0,71; IC95%: 0,64-0,79) y factor de riesgo en temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), pero no en extremo (RR = 1,1; IC95%: 0,99-1,22). La heterogeneidad de los modelos fue alta (I2 = 60%), y esta medida no se modificó en la metarregresión. Las temperaturas frías moderadas y extremas tienen un efecto protector, mientras que las temperaturas moderadamente altas aumentan el riesgo. Sin embargo, la temperatura mínima del aire no explica la variabilidad de la región, ni siquiera con las demás variables en metarregresión.

Cryptic circulation of chikungunya virus in São Jose do Rio Preto, Brazil, 2015-2019.

BACKGROUND: Chikungunya virus (CHIKV) has spread across Brazil with varying incidence rates depending on the affected areas. Due to cocirculation of arboviruses and overlapping disease symptoms, CHIKV infection may be underdiagnosed. To understand the lack of CHIKV epidemics in São José do Rio Preto (SJdRP), São Paulo (SP), Brazil, we evaluated viral circulation by investigating anti-CHIKV IgG seroconversion in a prospective study of asymptomatic individuals and detecting anti-CHIKV IgM in individuals suspected of dengue infection, as well as CHIKV presence in Aedes mosquitoes. The opportunity to assess two different groups (symptomatic and asymptomatic) exposed at the same geographic region aimed to broaden the possibility of identifying the viral circulation, which had been previously considered absent. METHODOLOGY/PRINCIPAL FINDINGS: Based on a prospective population study model and demographic characteristics (sex and age), we analyzed the anti-CHIKV IgG seroconversion rate in 341 subjects by ELISA over four years. The seroprevalence increased from 0.35% in the first year to 2.3% after 3 years of follow-up. Additionally, we investigated 497 samples from a blood panel collected from dengue-suspected individuals during the 2019 dengue outbreak in SJdRP. In total, 4.4% were positive for anti-CHIKV IgM, and 8.6% were positive for IgG. To exclude alphavirus cross-reactivity, we evaluated the presence of anti-Mayaro virus (MAYV) IgG by ELISA, and the positivity rate was 0.3% in the population study and 0.8% in the blood panel samples. In CHIKV and MAYV plaque reduction neutralization tests (PRNTs), the positivity rate for CHIKV-neutralizing antibodies in these ELISA-positive samples was 46.7%, while no MAYV-neutralizing antibodies were detected. Genomic sequencing and phylogenetic analysis revealed CHIKV genotype ECSA in São José do Rio Preto, SP. Finally, mosquitoes collected to complement human surveillance revealed CHIKV positivity of 2.76% of A. aegypti and 9.09% of A. albopictus (although it was far less abundant than A. aegypti) by RT-qPCR. CONCLUSIONS/SIGNIFICANCE: Our data suggest cryptic CHIKV circulation in SJdRP detected by continual active surveillance. These low levels, but increasing, of viral circulation highlight the possibility of CHIKV outbreaks, as there is a large naïve population. Improved knowledge of the epidemiological situation might aid in outbreaks prevention.

Severe metapneumovirus infections among immunocompetent and immunocompromised patients admitted to hospital with respiratory infection.

Human metapneumovirus (hMPV) is considered an important cause of acute respiratory infections. hMPV can cause morbidity in hematopoietic stem cell transplant recipients and recent research has demonstrated that it is an important virus in patients admitted to hospital with respiratory infections and suspected of having pandemic 2009 influenza A (H1N1pdm09) virus. The purpose of this study was to investigate infections caused by hMPV in two groups of patients admitted to hospital: Immunocompromized patients with a potential risk of severe outcomes and immunocompetent patients with severe acute respiratory syndrome. A total of 288 samples were tested: 165 samples were collected from patients with suspected influenza A (H1N1) pdm09 infection during the first pandemic wave in 2009; and 123 samples were collected from patients of a hematopoietic stem cell transplantation program in 2008-2009. Amplification of the hMPV genes was performed by polymerase chain reaction. This was followed by sequencing and phylogenetic analysis. hMPV was detected in 14.2% (41/288) of all samples: 17% (28/165) of immunocompetent patients with suspected H1N1 infection and 10.6% (13/123) among hematopoietic stem cell transplant recipients. hMPV accounted for 12.1% (8/66) of immunocompetent adults patients with severe respiratory infections (median age, 55.9 years). Two hMPV subtypes were identified, A2 (26.9%; 7/26) and B2 (73.1%; 19/26) but no difference was observed between the patient groups in terms of age or immunosuppression level. This study highlights the significance of hMPV in immunocompetent adult patients with severe infections and further investigations are recommended for understanding the impact of this virus.

A survey strategy for human respiratory syncytial virus detection among haematopoietic stem cell transplant patients: epidemiological and methodological analysis.

Human respiratory syncytial virus (HRSV) causes severe infections among children and immunocompromised patients. We compared HRSV infections among Haematopoietic Stem Cell Transplant program (HSCT) patients and children using direct immunofluorescence (DFA), point-of-care RSV Bio Easy® and a polymerase chain reaction (PCR) assay. Overall, 102 samples from HSCT patients and 128 from children obtained positivity rate of 18.6% and 14.1% respectively. PCR sensitivity was highest mainly on samples collected after five days of symptoms onset. A combination of both DFA and reverse transcriptase-PCR methods for HSCT high-risk patients is the best diagnostic flow for HRSV diagnosis among these patients.

Infections with human coronaviruses NL63 and OC43 among hospitalised and outpatient individuals in São Paulo, Brazil.

The incidence and clinical features of human coronaviruses (HCoVs) among Brazilian patients with respiratory illness are not well known. We investigated the prevalence of HCoVs among Brazilian outpatients and hospitalised patients with respiratory illnesses during 2009 and 2010. To identify the HCoVs, pancoronavirus and species-specific reverse-transcriptase polymerase chain reaction assays were performed. Five of 394 samples were positive for HCoVs (1.2%): 1/182 (0.5%) outpatients and 4/212 (1.8%) hospitalised patients. The OC43 and NL63 HCoVs were identified. Two patients were admitted to the intensive care unit. Underlying chronic disease was reported in cases and one diabetic adult died. HCoVs can cause lower respiratory infections and hospitalisation. Patients with pre-existing conditions and respiratory infections should be evaluated for HCoV infections.

Serine proteases in neutrophil extracellular traps exhibit anti-Respiratory Syncytial Virus activity.

Human respiratory syncytial virus (hRSV) is an infectious agent in infants and young children which there are no vaccines or drugs for treatment. Neutrophils are recruited for airway, where they are stimulated by hRSV to release large amounts of neutrophil extracellular traps (NETs). NETs are compound by DNA and proteins, including microbicidal enzymes. They constitute a large part of the mucus accumulated in the lung of patients, compromising their breathing capacity. In contrast, NETs can capture/inactivate hRSV, but the molecules responsible for this effect are unknown. OBJECTIVES: We selected microbicidal NET enzymes (elastase, myeloperoxidase, cathepsin-G, and proteinase-3) to assess their anti-hRSV role. METHODS AND RESULTS: Through in vitro assays using HEp-2 cells, we observed that elastase, proteinase-3, and cathepsin-G, but not myeloperoxidase, showed virucidal effects even at non-cytotoxic concentrations. Elastase and proteinase-3, but not cathepsin-G, cleaved viral F-protein, which is responsible for viral adhesion and fusion with the target cells. Molecular docking analysis indicated the interaction of these macromolecules in the antigenic regions of F-protein through the active regions of the enzymes. CONCLUSIONS: Serine proteases from NETs interact and inactive hRSV. These results contribute to the understanding the role of NETs in hRSV infection and to designing treatment strategies for the inflammatory process during respiratory infections.

An exploration of the political, social, economic and cultural factors affecting how different global regions initially reacted to the COVID-19 pandemic.

Responses to the early (February-July 2020) COVID-19 pandemic varied widely, globally. Reasons for this are multiple but likely relate to the healthcare and financial resources then available, and the degree of trust in, and economic support provided by, national governments. Cultural factors also affected how different populations reacted to the various pandemic restrictions, like masking, social distancing and self-isolation or self-quarantine. The degree of compliance with these measures depended on how much individuals valued their needs and liberties over those of their society. Thus, several themes may be relevant when comparing pandemic responses across different regions. East and Southeast Asian populations tended to be more collectivist and self-sacrificing, responding quickly to early signs of the pandemic and readily complied with most restrictions to control its spread. Australasian, Eastern European, Scandinavian, some Middle Eastern, African and South American countries also responded promptly by imposing restrictions of varying severity, due to concerns for their wider society, including for some, the fragility of their healthcare systems. Western European and North American countries, with well-resourced healthcare systems, initially reacted more slowly, partly in an effort to maintain their economies but also to delay imposing pandemic restrictions that limited the personal freedoms of their citizens.

Adjusting RT-qPCR conditions to avoid unspecific amplification in SARS-CoV-2 diagnosis.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 and quickly spread around the world, forcing global health authorities to develop protocols for its diagnosis. Here we report dimer formation in the N2 primers-probe set (CDC 2019-nCoV Real-Time RT-PCR) used in the diagnostic routine, and propose alternatives to reduce dimerization events. Late unspecific amplifications were visualized in 56.4% of negative samples and 57.1% of no-template control, but not in positive samples or positive control. In silico analysis and gel electrophoresis confirmed the dimer formation. The RT-qPCR parameters were optimized and the late unspecific amplifications decreased to 11.5% in negative samples and no-template control. The adjustment of PCR parameters was essential to reduce the risk of false-positives results and to avoid inclusive results requiring repeat testing, which increases the costs and generates delays in results or even unnecessary requests for new samples.

Rhinovirus species and their clinical presentation among different risk groups of non-hospitalized patients.

Infections caused by Human Rhinoviruses (HRVs) account for 25-50% of respiratory illnesses among individuals presenting influenza-like illness (ILI). HRVs could be classified in at least three species: HRV-A, HRV-B, and HRV-C. The HRV-C species has frequently been described among children and has led to severe illness resulting in hospitalization; however, the occurrence among adults is unknown. The aim of this study was to assess the clinical presentation and species distribution of HRV infections in different populations during 2001-2008. A total of 770 samples were collected. Subjects consisted of 136 adults from the general community and 207 health-care workers (2001-2003), 232 renal-transplanted outpatients (2002-2004), 70 children with congenital heart disease (2005) and 125 children from a day-care center (2008). Amplification of HRV genes was performed by reverse transcriptase-polymerase chain reaction (RT-PCR) and followed by sequencing and phylogenetic analysis. HRV was detected in 27.4% of samples (211/770), with 72 children (36.9%) and 139 adults infected (24.2%). A total of 89.61% (138/154) unknown HRV strains were sequenced, and 79.22% (122/138) were analyzed. We identified 74 isolates (60.7%) of the HRV A species, 21 (17.2%) of the HRV B species and 27 isolates (22.1%) of the HRV C species. HRV species A and B caused ILI among adult patients, whereas HRV-C did not. The dynamics of infection among different species deserve further analysis.

Genomic Analyses of Potential Novel Recombinant Human Adenovirus C in Brazil.

Human Adenovirus species C (HAdV-C) is the most common etiologic agent of respiratory disease. In the present study, we characterized the nearly full-length genome of one potential new HAdV-C recombinant strain constituted by Penton and Fiber proteins belonging to type 89 and a chimeric Hexon protein of types 1 and 89. By using viral metagenomics techniques, we screened out, in the states of Tocantins and Pará, Northern and North regions of Brazil, from 2010 to 2016, 251 fecal samples of children between 0.5 to 2.5 years old. These children were presenting acute diarrhea not associated with common pathogens (i.e., rotavirus, norovirus). We identified two HAdV-C strains in two distinct patients. Phylogenetic analysis performed using all complete genomes available at GenBank database indicated that one strain (HAdV-C BR-245) belonged to type 1. The phylogenetic analysis also indicated that the second strain (HAdV-C BR-211) was located at the base of the clade formed by the newly HAdV-C strains type 89. Recombination analysis revealed that strain HAdV-C BR-211 is a chimera in which the variable regions of Hexon gene combined HAdV-C1 and HAdV-C89 sequences. Therefore, HAdV-C BR-211 strain possesses a genomic backbone of type HAdV-C89 and a unique insertion of HAdV-C1 in the Hexon sequence. Recombination may play an important driving force in HAdV-C diversity and evolution. Studies employing complete genomic sequencing on circulating HAdV-C strains in Brazil are needed to understand the clinical significance of the presented data.

The occurrence of polyomaviruses WUPyV and KIPyV among patients with severe respiratory infections.

In 2007, the new polyomaviruses WUPyV and KIPyV were identified in patients with acute respiratory infections. The aim of this study was to investigate these viruses in hospitalized patients with severe acute respiratory infection (SARI). A retrospective study was conducted with 251 patients, from April 2009 to November 2010, using nasopharyngeal aspirates, naso- and oropharyngeal swab samples from hospitalized patients (children < 12 years and adults) who had SARI within 7 days of the onset of symptoms, including fever (> 38.8 °C), dyspnea, and cough. Clinical and epidemiological information was obtained through standardized questionnaire. Enrolled patients were initially suspected to have influenza A(H1N1)pdm09 infections. WUPyV and KIPyV were detected by real-time PCR. Samples were also tested for influenza A and B viruses, human respiratory syncytial virus, rhinovirus, metapneumovirus, coronavirus, adenovirus, and parainfluenza viruses. WUPyV and KIPyV were detected in 6.77% (4.78% and 1.99%, respectively) of hospitalized patients with SARI. All samples from children showed coinfections (rhinovirus was the most commonly detected). Six adults had polyomavirus infection and four (1.6%) had monoinfection. Of them, 3 reported comorbidities including immunosuppression and 1 patient had worse outcome, requiring ICU admission. These preliminary data may suggest a possible role of polyomaviruses in SARI among immunocompromised adult patients.

Relação entre temperatura do ar e incidência de dengue: estudo de séries temporais em Minas Gerais, Brasil (2010-2019) / Relationship between air temperature and dengue incidence: time series study in Minas Gerais, Brazil (2010-2019) / Relación entre la temperatura del aire y la incidencia del dengue: estudio de series temporales en Minas Gerais, Brasil (2010-2019)

Resumo A temperatura do ar é um fator climático que afeta a incidência da dengue, com efeitos variando conforme o tempo e o espaço. Investigamos a relação entre a temperatura mínima do ar e a incidência da doença em Minas Gerais, Brasil, e avaliamos a influência de variáveis socioeconômicas e geográficas nessa relação, calculando-se o risco relativo (RR). Este é um estudo de série temporal com análise conduzida em três etapas distintas: modelagem por uso de distributed lag non-linear model (modelos não-lineares distributivos com defasagem), metanálise dos modelos obtidos e metarregressão com dados geográficos e socioeconômicos. A temperatura mínima foi um fator de proteção quando em temperaturas frias extremas (RR = 0,65; IC95%: 0,56-0,76) e moderadas (RR = 0,71; IC95%: 0,64-0,79) e fator de risco em temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), mas não em extremo (RR = 1,1; IC95%: 0,99-1,22). A heterogeneidade dos modelos foi elevada (I2 = 60%) e essa medida não foi alterada em metarregressão. Temperaturas frias moderadas e extremas causam efeito protetivo, enquanto moderadas quentes aumentam o risco. No entanto, a temperatura mínima do ar não explica nem a variabilidade da região, nem mesmo com as outras variáveis em metarregressão.

Abstract Air temperature is a climatic factor that affects the incidence of dengue, with effects varying according to time and space. We investigated the relationship between minimum air temperature and dengue incidence in Minas Gerais, Brazil, and evaluated the influence of socioeconomic and geographic variables on this relationship. This is a time series study with analysis conducted in three distinct stages: modeling using a distributed lag non-linear model, meta-analysis of models obtained, and meta-regression with geographic and socioeconomic data. Minimum temperature was a protective factor at extreme cold temperatures (RR = 0.65; 95%CI: 0.56-0.76) and moderate cold temperatures (RR = 0.71; 95%CI: 0.64-0.79), and a risk factor at moderate hot temperatures (RR = 1.15; 95%CI: 1.07-1.24), but not at extreme hot temperatures (RR = 1.1; 95%CI: 0.99-1.22). Heterogeneity of the models was high (I2 = 60%), which was also observed in meta-regression. Moderate and extreme cold temperatures have a protective effect, while moderate hot temperatures increase the risk. However, minimum air temperature does not explain the variability in the region, not even with the other variables in meta-regression.

Resumen La temperatura del aire es un factor climático que afecta la incidencia del dengue, con efectos que varían según el tiempo y el territorio. Investigamos la relación entre la temperatura mínima del aire y la incidencia de la enfermedad en Minas Gerais, Brasil, y evaluamos la influencia de variables socioeconómicas y geográficas en esta relación. Se trata de un estudio de serie temporal cuyo análisis se realiza en tres etapas distintas: modelación mediante el uso de distributed lag non-linear model (modelos distributivos no lineales con retraso), metaanálisis de los modelos obtenidos y metarregresión con datos geográficos y socioeconómicos. La temperatura mínima fue un factor de protección ante temperaturas extremadamente frías (RR = 0,65; IC95%: 0,56-0,76) y moderadas (RR = 0,71; IC95%: 0,64-0,79) y factor de riesgo en temperaturas de calor moderado (RR = 1,15; IC95%: 1,07-1,24), pero no en extremo (RR = 1,1; IC95%: 0,99-1,22). La heterogeneidad de los modelos fue alta (I2 = 60%), y esta medida no se modificó en la metarregresión. Las temperaturas frías moderadas y extremas tienen un efecto protector, mientras que las temperaturas moderadamente altas aumentan el riesgo. Sin embargo, la temperatura mínima del aire no explica la variabilidad de la región, ni siquiera con las demás variables en metarregresión.

Excess mortality is associated with influenza A (H1N1) in patients with severe acute respiratory illness.

BACKGROUND: Acute respiratory infections caused by viruses are among the leading causes of morbidity and mortality. The inflammatory response that follows viral infection is important for the control of virus proliferation. However, if overwhelming, may be associated with complicated outcomes. OBJECTIVES: We assessed the clinical characteristics of patients with severe acute respiratory illness (SARI) evolving to acute respiratory distress syndrome (ARDS) and the factors related to death. STUDY DESIGN: Prospective study in 273 adult patients with SARI performed in a university-affiliated 800-bed hospital serving an area of epidemiologic vigilance of 102 municipalities and more than 2 million inhabitants. Influenza A (H1N1) 2009 (A/H1N1), influenza A H3N2, and influenza B were tested in all patients by RT-PCR. RESULTS: The overall hospital mortality rate was 17.6%. A total of 30.4% of patients tested positive for influenza A/H1N1. Patients with SARI that evolved to ARDS took significantly longer to take the first dose of oseltamivir (6.0 vs 1.0 days, p=0.002). Patients with H1N1 positive tests had almost 3 times higher probability of death, despite having significantly less comorbidities (p=0.027). The influenza A/H1N1 pdm09 vaccine reduced the odds of death by 78%. Nonsurvivors had a more intense inflammatory response than did survivors at 48 h (C-reactive protein: 31.0 ± 17.5 vs. 14.6 ± 8.9 mg/dl, p=0.001) as well as a more positive fluid balance. CONCLUSIONS: Hospital mortality associated with influenza H1N1-associated SARI and ARDS continued to be high years after the 2009 pandemic in a population with low vaccine coverage. Antiviral treatment started more than two days after onset of symptoms was more frequently associated with ARDS and death and, having had vaccine against influenza A (H1N1) was a factor independently related to survival.

Comparative global epidemiology of influenza, respiratory syncytial and parainfluenza viruses, 2010-2015.

OBJECTIVES: To improve our understanding of the global epidemiology of common respiratory viruses by analysing their contemporaneous incidence at multiple sites. METHODS: 2010-2015 incidence data for influenza A (IAV), influenza B (IBV), respiratory syncytial (RSV) and parainfluenza (PIV) virus infections were collected from 18 sites (14 countries), consisting of local (n = 6), regional (n = 9) and national (n = 3) laboratories using molecular diagnostic methods. Each site submitted monthly virus incidence data, together with details of their patient populations tested and diagnostic assays used. RESULTS: For the Northern Hemisphere temperate countries, the IAV, IBV and RSV incidence peaks were 2-6 months out of phase with those in the Southern Hemisphere, with IAV having a sharp out-of-phase difference at 6 months, whereas IBV and RSV showed more variable out-of-phase differences of 2-6 months. The tropical sites Singapore and Kuala Lumpur showed fluctuating incidence of these viruses throughout the year, whereas subtropical sites such as Hong Kong, Brisbane and Sydney showed distinctive biannual peaks for IAV but not for RSV and PIV. CONCLUSIONS: There was a notable pattern of synchrony of IAV, IBV and RSV incidence peaks globally, and within countries with multiple sampling sites (Canada, UK, Australia), despite significant distances between these sites.

Acute respiratory infection and influenza-like illness viral etiologies in Brazilian adults.

Influenza-like illness (ILI) definitions have been used worldwide for influenza surveillance. These different case definitions can vary with regard to sensitivity and predictive values for laboratory confirmed influenza. The literature has indicated the inclusion of other viruses may be the cause of these variable results. The objective of the study was to evaluate ILI national sentinel criteria and viral etiologies in adults diagnosed with acute respiratory infection (ARI) and/or ILI from 2001 to 2003 in Sao Paulo, Brazil. Clinical and laboratory evaluations were observed from 420 adults and collected on a daily basis from outpatient care units at University Hospital. The ILI definition included: fever plus at least one respiratory symptom (cough and/or sore throat) and one constitutional symptom (headache, malaise, myalgia, sweat or chills, or fatigue). DFA and RT-PCR for influenza, parainfluenza, respiratory syncytial virus, adenovirus, enterovirus, coronavirus, rhinovirus, and metapneumovirus were performed on nasal washes and 61.8% resulted positive. The respiratory viruses detected most often were influenza and rhinovirus. ILI was reported for 240/420 patients (57.1%), with influenza and rhinovirus etiologies accounting for 30.9% and 19.6%, respectively. Rhinovirus peak activity was concurrent with the influenza season. These findings highlight the implications of other viruses in ILI etiology and suggest that during the influenza season, this clinical overlap must be considered in the diagnosis and clinical management of patients.

Influenza detection and subtyping by reverse transcriptase polymerase chain reaction-restriction fragment length polymorphism for laboratory surveillance in Brazil.

A duplex reverse transcriptase polymerase chain reaction-restriction fragment length polymorphism for influenza virus subtyping was applied to 412 patient samples. The assay was able to discriminate all 47 influenza A H1N1 and H3N2 viruses. This rapid technique assessed if positive samples were current circulating strains or an emergent one and could be used as the 1st test in prepandemic stages.

Respiratory syncytial virus evaluation among asymptomatic and symptomatic subjects in a university hospital in Sao Paulo, Brazil, in the period of 2009-2013.

BACKGROUND: The respiratory syncytial virus (RSV) is recognized as an important cause of respiratory tract infections. Immunocompromised patients, healthcare workers (HCWs) and children contacts are at increased risk of acquiring the infection. However, the impact of asymptomatic infection in transmission has not been well studied. OBJECTIVES: this study evaluated the frequency and viral load (VL) of RSV in nasal swab samples of individuals with different risk factors for acquiring infection in a university hospital in Sao Paulo, Brazil. METHODS: We included 196 symptomatic children and their 192 asymptomatic caregivers, 70 symptomatic and 95 asymptomatic HCWs, 43 samples from symptomatic HIV-positive outpatients, and 100 samples of asymptomatic HIV patients in the period of 2009-2013. RESULTS: RSV infection was detected in 10.1% (70/696) of samples, 4.4% (17/387) of asymptomatic patients, and 17.1% (53/309) from symptomatic patients. (P < .0001). The VL of symptomatic patients (4.7 log copies/mL) was significantly higher compared to asymptomatic patients (2.3 log copies/mL). RSV detection among asymptomatic caregivers (6.8%; 13/192) was significantly higher compared to other asymptomatic adults, HIV and HCWs (2.0%; 4/195; P = .0252). A close contact with an infected child at home was an important risk to RSV acquisition [OR 22.6 (95% CI 4.8-106.7)]. Children who possibly transmitted the virus to their asymptomatic contacts had significantly higher viral load than children who probably did not transmit (P < .0001). CONCLUSIONS: According to our results, it is important to know if people circulating inside the hospital have close contact with acute respiratory infected children.

Perfil clínico-epidemiológico de pacientes com suspeita de síndrome respiratória aguda grave durante um período de cinco anos em um município de grande porte de Minas Gerais / Clinical and epidemiological profile of severe acute respiratory syndrome suspected patients during a period of five years in a large city of Minas Gerais

Introdução: As infecções do trato respiratório representam importante causa de morbidade e mortalidade no mundo. Dentre as apresentações clínicas das infecções virais temos a síndrome respiratória aguda grave (SRAG) que é um quadro de síndrome gripal com sinais de gravidade, representando um agravo de notificação compulsória. Objetivo: Avaliar a ocorrência da síndrome respiratória aguda grave na população de Juiz de Fora, Minas Gerais, durante o período de 5 anos. Material e Métodos: Os dados clínico/epidemiológicos presentes nas fichas de notificação entre os anos de 2016 a 2021 foram fornecidos pela vigilância epidemiológica do município sendo submetidos à análise, perfazendo 20.817 pacientes estudados. Resultados: A média de idade entre 2016 e 2019 foi de 24,36 anos (DP± 25,7) e entre 2020 e 2021 a média foi de 52,17 anos (DP± 24,4). Entre 2016-2019, o acometimento por faixa etária, se concentrou entre pacientes infantis (0-2 anos) 25,41% dos casos, crianças (3-12 anos) 22,31% e adultos jovens (18-39 anos) 23,45% dos casos. Entre 2019 e 2021, houve mudança nesse perfil com maior ocorrência dos casos concentrados em adultos de meia idade e idosos. Em relação à etiologia, o vírus Influenza foi responsável por 6,11 % dos casos, 19,4% foram causados por outros vírus respiratórios e o SARS-CoV-2 em 2 anos foi responsável por 72,59% dos casos. Entre 2019 e 2021, 99,41% dos casos precisaram de internação sendo que 48,01% dos pacientes foram para a unidade de terapia intensiva (UTI). Pacientes com fatores de risco apresentaram Odds Ratio de 3,7 de evoluir para óbito. Conclusão: Em Juiz de Fora, há um predomínio de casos em pacientes de 0-12 anos seguidos por adultos jovens (18-39 anos). A Covid-19 alterou o perfil epidemiológico de acometimento. Outros vírus respiratórios, além do Influenza podem ser etiologia de casos graves. Quase 100% dos casos necessitaram de internação em enfermaria, além disso, quase 50% dos casos necessitam de cuidados em UTI.

Introduction: Respiratory tract infections represent a significant cause of morbidity and mortality worldwide. Among the clinical presentations of viral infections the Severe Acute Respiratory Syndrome (SARS) which is a severe flu-like syndrome with signs of severity, representing a notifiable condition. Objective: To evaluate the occurrence of Severe Acute Respiratory Syndrome in the population of Juiz de Fora, MG, during a 5-year period. Material and Methods: Clinical/epidemiological data from notification forms between the years 2016 and 2021 were provided by the epidemiological surveillance of the municipality and subjected to analysis, comprising 20,817 studied patients.Results: The mean age between 2016 and 2019 was 24.36 years (SD ± 25.7), and between 2020 and 2021, the average age was 52.17 years (SD ± 24.4). Between 2016-2019, the affected age groups were mainly Infants (0-2 years) accounting for 25.41% of cases, Children (3-12 years) with 22.31%, and Young Adults (18-39 years) with 23.45% of cases. Between 2019 and 2021, there was a profile change, with a higher occurrence of cases concentrated among middle-aged adults and the elderly. Regarding etiology, the Influenza virus was responsible for 6.11% of cases, 19.4% were caused by other respiratory viruses, and the SARS-CoV-2 virus accounted for 72.59% of cases in a years period. Between 2019-2021, 99.41% of cases required hospitalization, with 48.01% of patients admitted to the ICU. Patients with risk factors presented an odds ratio of 3.7 to progress to death. Conclusion: In Juiz de Fora city, there is a predominance of cases in patients aged 0-12, followed by young adults (18-39 years). COVID-19 has altered the epidemiological profile of SARS. Besides Influenza, other respiratory viruses can be the etiology of severe cases. Almost 100% of the cases required hospitalization in the ward, and nearly 50% of the cases required ICU care.

Complete Genome Sequences of Six Human Bocavirus Strains from Patients with Acute Gastroenteritis in the North Region of Brazil.

Human bocavirus (HBoV) is commonly associated with acute respiratory tract illness and gastroenteritis. We report six complete genomic sequences of HBoV strains from patients with gastroenteritis in Belém do Pará and Tocantins in the North Region of Brazil. Phylogenetic analysis indicated that the six HBoV strains belong to genotypes 1, 2, and 3.