Epidemiological aspects of influenza A related to climatic conditions during and after a pandemic period in the city of Salvador, northeastern Brazil

During the influenza pandemic of 2009, the A(H1N1)pdm09, A/H3N2 seasonal and influenza B viruses were observed to be co-circulating with other respiratory viruses. To observe the epidemiological pattern of the influenza virus between May 2009-August 2011, 467 nasopharyngeal aspirates were collected from children less than five years of age in the city of Salvador. In addition, data on weather conditions were obtained. Indirect immunofluorescence, real-time transcription reverse polymerase chain reaction (RT-PCR), and sequencing assays were performed for influenza virus detection. Of all 467 samples, 34 (7%) specimens were positive for influenza A and of these, viral characterisation identified Flu A/H3N2 in 25/34 (74%) and A(H1N1)pdm09 in 9/34 (26%). Influenza B accounted for a small proportion (0.8%) and the other respiratory viruses for 27.2% (127/467). No deaths were registered and no pattern of seasonality or expected climatic conditions could be established. These observations are important for predicting the evolution of epidemics and in implementing future anti-pandemic measures.

Detection of respiratory viruses by real-time polymerase chain reaction in outpatients with acute respiratory infection

Viruses are the major contributors to the morbidity and mortality of upper and lower acute respiratory infections (ARIs) for all age groups. The aim of this study was to determine the frequencies for a large range of respiratory viruses using a sensitive molecular detection technique in specimens from outpatients of all ages with ARIs. Nasopharyngeal aspirates were obtained from 162 individuals between August 2007-August 2009. Twenty-three pathogenic respiratory agents, 18 respiratory viruses and five bacteria were investigated using multiplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) and indirect immunofluorescence assay (IIF). Through IIF, 33 (20.4%) specimens with respiratory virus were recognised, with influenza virus representing over half of the positive samples. Through a multiplex real-time RT-PCR assay, 88 (54.3%) positive samples were detected; the most prevalent respiratory viral pathogens were influenza, human rhinovirus and respiratory syncytial virus (RSV). Six cases of viral co-detection were observed, mainly involving RSV. The use of multiplex real-time RT-PCR increased the viral detection by 33.9% and revealed a larger number of respiratory viruses implicated in ARI cases, including the most recently described respiratory viruses [human bocavirus, human metapneumovirus, influenza A (H1N1) pdm09 virus, human coronavirus (HCoV) NL63 and HCoV HKU1].

Evaluation of Haemophilus influenzaetype b carrier status among children 10 years after the introduction of Hib vaccine in Brazil

The aim of the present study was to assess the prevalence of Haemophilus influenzaetype b (Hib) nasopharyngeal (NP) colonisation among healthy children where Hib vaccination using a 3p+0 dosing schedule has been routinely administered for 10 years with sustained coverage (> 90%). NP swabs were collected from 2,558 children who had received the Hib vaccine, of whom 1,379 were 12-< 24 months (m) old and 1,179 were 48-< 60 m old. Hi strains were identified by molecular methods. Hi carriage prevalence was 45.1% (1,153/2,558) and the prevalence in the 12-< 24 m and 48-< 60 m age groups were 37.5% (517/1,379) and 53.9% (636/1,179), respectively. Hib was identified in 0.6% (16/2,558) of all children in the study, being 0.8% (11/1,379) and 0.4% (5/1,179) among the 12-< 24 m and 48-< 60 m age groups, respectively. The nonencapsulate Hi colonisation was 43% (n = 1,099) and was significantly more frequent at 48-< 60 m of age (51.6%, n = 608) compared with that at 12-< 24 m of age (35.6%, n = 491). The overall resistance rates to ampicillin and chloramphenicol were 16.5% and 3.7%, respectively; the co-resistance was detected in 2.6%. Our findings showed that the Hib carrier rate in healthy children under five years was very low after 10 years of the introduction of the Hib vaccine.

Viral aetiology of common colds of outpatient children at primary care level and the use of antibiotics

Although antibiotics are ineffective against viral respiratory infections, studies have shown high rates of prescriptions worldwide. We conducted a study in Brazil to determine the viral aetiologies of common colds in children and to describe the use of antibiotics for these patients. Children up to 12 years with common colds were enrolled from March 2008-February 2009 at a primary care level facility and followed by regular telephone calls and medical consultations. A nasopharyngeal wash was obtained at enrollment and studied by direct fluorescence assay and polymerase chain reaction for nine different types of virus. A sample of 134 patients was obtained, median age 2.9 years (0.1-11.2 y). Respiratory viruses were detected in 73.9% (99/134) with a coinfection rate of 30.3% (30/99). Rhinovirus was the most frequent virus (53/134; 39.6%), followed by influenza (33/134; 24.6%) and respiratory syncytial virus (8/134; 13.4%). Antibiotic prescription rate was 39.6% (53/134) and 69.8% (37/53) were considered inappropriate. Patients with influenza infection received antibiotics inappropriately in a greater proportion of cases when compared to respiratory syncytial virus and rhinovirus infections (p = 0.016). The rate of inappropriate use of antibiotics was very high and patients with influenza virus infection were prescribed antibiotics inappropriately in a greater proportion of cases.

Radiographic adenoid evaluation: proposal of an objective parameter

Objective The objective of the present study was to evaluate current radiographic parameters designed to investigate adenoid hypertrophy and nasopharyngeal obstruction, and to present an alternative radiographic assessment method. Materials and Methods In order to do so, children (4 to14 years old) who presented with nasal obstruction or oral breathing complaints were submitted to cavum radiographic examination. One hundred and twenty records were evaluated according to quantitative radiographic parameters, and data were correlated with a gold-standard videonasopharyngoscopic study, in relation to the percentage of choanal obstruction. Subsequently, a regression analysis was performed in order to create an original model so the percentage of the choanal obstruction could be predicted. Results The quantitative parameters demonstrated moderate, if not weak correlation with the real percentage of choanal obstruction. The regression model (110.119*A/N) demonstrated a satisfactory ability to “predict” the actual percentage of choanal obstruction. Conclusion Since current adenoid quantitative radiographic parameters present limitations, the model presented by the present study might be considered as an alternative assessment method in cases where videonasopharyngoscopic evaluation is unavailable.

Outbreaks of rhinofacial and rhinopharyngeal zygomycosis in sheep in Paraíba, northeastern Brazil

Two outbreaks of zigomycosis with rhinofacial and two other with rhinopharyngeal lesions involving fungi with filamentous coaenocytic hyphae characteristic of entomoph-thoramycetous fungi are reported in the state of Paraíba, northeastern Brazil. One outbreak of rhinofacial zygomycosis occurred during the rainy season affecting 5 sheep. Another outbreak of the clinical form affected one out of 40 sheep during the dry season. Common clinical signs of the rhinofacial infection were bilateral serosanguineous nasal discharge with swelling of nostrils, upper lip, and the skin of the face. At necropsy the nasal mucosa showed dark brownish ulcerated areas which extended from the mucocutaneous region to 10cm inside the nasal vestibule. The mucosa of the hard palate was also ulcerated. The cutting surface of nostrils and palate showed a brownish or red spongeous tissue of friable consistency. One outbreak of rhinopharyngitis took place on an irrigated coconut farm; 7 out of 60 adult sheep were affected. Another outbreak affected a sheep in a flock of 80 during the dry season. Clinical signs as noisy respiration and dyspnoea due to mechanical blockage of the nasal cavities, swelling of the nostrils, and serosanguineous nasal discharge were observed. Six out of 8 sheep in this group showed exophthalmia, keratitis and unilateral corneal ulceration of the eye. The sheep either died of their infection or were euthanized after a clinical course of 7-30 days. At necropsy there was a dense yellow exudate in the nasopharyngeal area affecting the ethmoidal region, turbinate bones, paranasal sinuses, hard and soft palates, orbital cavity, pharynges, regional muscles and lymph nodes. Histopathologically both forms of the disease showed multifocal granulomas with an eosinophilic necrotic reaction (Splendore-Hoeppli phenomenon) containing ribbon-type coenocytic hyphae with 7-30mum in diameter similar to hyphae of zygomycetous fungi, possibly Conidiobolus spp. Outbreaks of both forms of mycotic rhinitis are common in northeastern Brazil and in other regions of the country.

Caspase-8 and p38MAPK in DATS-induced apoptosis of human CNE2 cells

Nasopharyngeal carcinoma is a common malignancy in Southern China of uncertain etiologic origin. Diallyl trisulfide (DATS), one of the major components of garlic (Allium sativum), is highly bactericidal and fungicidal. In this study, we investigated the function of p38 mitogen-activated protein kinase (MAPK) and caspase-8 in DATS-induced apoptosis of human CNE2 cells using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide], flow cytometry assay, and Western blotting. After CNE2 cells were treated with DATS (50, 100, or 150 μM) for 24 h, cell viability rates were 75.9, 63.4 and 39.6%, and apoptosis rates were 24.5, 36.9, and 62.4%, respectively. The data showed that DATS induced CNE2 cell death in a dose-dependent manner. After human CNE2 cells were treated with 100 μM DATS and inhibitors (10 μM SB203580 and Z-LETD-FMK for p38MAPK and caspase-8, respectively), changes in cell viability and apoptosis and in p38MAPK and caspase-8 activity were detected. Cell viability rates were 66.5 and 68.1% and decreased 9.9 and 11.5% compared with inhibitor treatment alone. Apoptosis rates were 31.53 and 29.98% and increased 9.1 and 10% compared with inhibitor treatment alone. The results indicated that DATS activates p38MAPK and caspase-8, but both inhibitors have an effect on P38MAPK and caspase-8 activity. In conclusion, our data indicate that p38MAPK and caspase-8 are involved in the process of DATS-induced apoptosis in human CNE2 cells and interact with each other.