Cristina Calvo
Hospital Universitario La Paz
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Publication
Featured researches published by Cristina Calvo.
Journal of Clinical Virology | 2008
Cristina Calvo; María Luz García-García; Carolina Blanco; Mª Carmen Vázquez; Mª Elena Frías; Pilar Pérez-Breña; Inmaculada Casas
Abstract Background The clinical significance of the presence of more than one type of virus in the respiratory specimens of children with respiratory infections is not clear. Objectives To describe the clinical characteristics of multiple viral infections versus single infection by respiratory syncytial virus (RSV) in hospitalized infants. Study design This is a prospective study conducted in all infants under 2 years of age admitted for acute respiratory infection (September 2000–June 2003) in a secondary teaching hospital. Virological diagnosis was made by two different multiplex reverse transcription-nested polymerase chain reaction (RT-PCR) assays in nasopharyngeal aspirates. We describe the clinical characteristics of the patients with multiple viral infections and compare them to a group of 86 randomly selected patients infected only with RSV. Results 749 specimens taken were analyzed. Respiratory viruses were detected in 65.9% of the samples. 86 children had multiple viral infections (17.4% of all positive specimens). The most frequent clinical diagnosis in this group was recurrent wheezing in 44% and bronchiolitis in 52%. Fever was significantly more frequent (p <0.001), hospital stays were longer (p =0.05), and antibiotic treatment was used more (p =0.03) in infants with multiple viral infections than in the RSV-infected group. Conclusions Multiple viral infections are frequent in hospitalized children with respiratory tract disease (17.4%). Multiple viral infections are linked to higher fever, longer hospital stays and more frequent use of antibiotics than in the case of infants with single RSV infections.
Acta Paediatrica | 2010
Cristina Calvo; Francisco Pozo; María Luz García-García; M Sanchez; M Lopez-Valero; Pilar Pérez-Breña; Inmaculada Casas
Aim: We have designed a study with the objective of describing the clinical impact of other viruses different from the respiratory syncytial virus (RSV) in hospitalized infants with bronchiolitis.
Journal of Virology | 2010
Alfonsina Trento; Inmaculada Casas; Ana Calderón; María Luz García-García; Cristina Calvo; Pilar Pérez-Breña; José A. Melero
ABSTRACT The emergence of natural isolates of human respiratory syncytial virus group B (HRSV-B) with a 60-nucleotide (nt) duplication in the G protein gene in Buenos Aires, Argentina, in 1999 (A. Trento et al., J. Gen. Virol. 84:3115-3120, 2003) and their dissemination worldwide allowed us to use the duplicated segment as a natural tag to examine in detail the evolution of HRSV during propagation in its natural host. Viruses with the duplicated segment were all clustered in a new genotype, named BA (A. Trento et al., J. Virol. 80:975-984, 2006). To obtain information about the prevalence of these viruses in Spain, we tested for the presence of the duplicated segment in positive HRSV-B clinical samples collected at the Severo Ochoa Hospital (Madrid) during 12 consecutive epidemics (1996-1997 to 2007-2008). Viruses with the 60-nt duplication were found in 61 samples, with a high prevalence relative to the rest of B genotypes in the most recent seasons. Global phylogenetic and demographic analysis of all G sequences containing the duplication, collected across five continents up until April 2009, revealed that the prevalence of the BA genotype increased gradually until 2004-2005, despite its rapid dissemination worldwide. After that date and coinciding with a bottleneck effect on the population size, a relatively new BA lineage (BA-IV) replaced all other group B viruses, suggesting further adaptation of the BA genotype to its natural host.
Pediatric Pulmonology | 2006
María Luz García-García; Cristina Calvo; Pilar Pérez-Breña; J.M. De Cea; B. Acosta; Inmaculada Casas
Human metapneumovirus (hMPV), a condition recently described in the Netherlands, causes lower respiratory infections, particularly in young children and among the elderly. The objective of this study was to describe the characteristics of hMPV infections in hospitalized infants <2 years of age and to compare them to those of infections caused by respiratory syncytial virus (RSV). A prospective study was conducted on the clinical characteristics of infants admitted to hospital for respiratory infection through 5 years. Simultaneous detection of influenza A, B, and C viruses, RSV, and adenoviruses was performed in clinical samples by multiple reverse transcription nested‐PCR assay. The presence of hMPV was tested in all samples using two separate RT‐PCR tests. Some respiratory virus was detected in 70.5% of the 1,322 children included in the study. hMPV was found in 101 of the positive nasopharyngeal aspirates (10.8%), and was the most common virus after RSV and rhinovirus. Peak incidence was found in March. Over 80% of children were <12 months. The more common diagnoses were bronchiolitis (49.5%) and recurrent wheezing (45.5%). Fifty‐four percent of cases required oxygen therapy and, one percent, assisted ventilation. Thirty percent were co‐infections, with clinical characteristics indistinguishable from single infections. Seventy‐one hMPV single infections were compared to 88 RSV single infections. hMPV infections were significantly more frequent than RSV in infants older than 6 months (P = 0.04). Recurrent wheezing was diagnosed more frequently in hMPV patients (P = 0.001). All other variables tested were similar, in both groups. hMPV was the third most frequent virus after RSV and rhinovirus in infants <2 years of age, hospitalized for respiratory infection, and was associated with bronchiolitis and recurrent wheezing. hMPV predominantly occurred in spring. Co‐infections were frequent and clinically similar to single infections and RSV infections. Pediatr Pulmonol.
Journal of Clinical Virology | 2007
Francisco Pozo; Mari Luz García-García; Cristina Calvo; Isabel Cuesta; Pilar Pérez-Breña; Inmaculada Casas
Abstract Background The newly identified human bocavirus (HBoV), a member of the Parvoviridae family, has been associated to low respiratory tract infections in young children. Objectives To present the epidemiological profile and the main clinical characteristics showed by children infected with this virus in Spain. Study design We have studied the incidence of HBoV and other 15 respiratory viruses in 917 nasopharyngeal aspirates taken from 730 infants and children under age of 14 with acute lower respiratory tract infection from September-04 to August-06. Results HBoV was detected in 123 samples (13.4%) showing a seasonal distribution with November and December as the peak months. Out of the 558 samples which rendered a positive result for at least one of the virus tested, HBoV (22%) ranked fourth behind respiratory syncytial virus (181, 32%), adenoviruses (155, 28%) and rhinoviruses (136, 24%). Co-infections with HBoV and other respiratory viruses were detected in 74 out of 123 HBoV-positive specimens (60%). In addition, HBoV was also found in stool and, for the first time, in urine samples. Conclusions Results obtained provide further evidence that HBoV is involved in acute lower respiratory tract infections. HBoV-associated disease should not be limited to the respiratory tract.
Emerging Infectious Diseases | 2008
Thomas Briese; Neil Renwick; Marietjie Venter; Richard G. Jarman; Dhrubaa Ghosh; Sophie Köndgen; Sanjaya K. Shrestha; A. Mette Hoegh; Inmaculada Casas; Edgard V. Adjogoua; Chantal Akoua-Koffi; Khin Saw Aye Myint; David T. Williams; Glenys Chidlow; Ria van den Berg; Cristina Calvo; Orienka Koch; Gustavo Palacios; Vishal Kapoor; Joseph Villari; Samuel R. Dominguez; Kathryn V. Holmes; Gerry Harnett; David Smith; John S. Mackenzie; Heinz Ellerbrok; Brunhilde Schweiger; Kristian Schønning; Mandeep S. Chadha; Fabian H. Leendertz
Global surveillance for a novel rhinovirus genotype indicated its association with community outbreaks and pediatric respiratory disease in Africa, Asia, Australia, Europe, and North America. Molecular dating indicates that these viruses have been circulating for at least 250 years.
Pediatric Infectious Disease Journal | 2007
Cristina Calvo; María Luz García-García; Carolina Blanco; Francisco Pozo; Inmaculada Casas Flecha; Pilar Pérez-Breña
Background: Rhinovirus is a recognized cause of common cold, proven to cause asthma exacerbations in children. In Spain, no description exists, as yet, as to the degree of burden rhinovirus infections represent among hospitalized infants. Our aim was to describe rhinovirus infections in hospitalized children, under 2 years of age, and to compare these with patients infected with respiratory syncytial virus (RSV). Patients and Methods: The prospective study was performed between September 2003 and July 2005, in children <2 years of age, admitted at the Severo Ochoa Hospital (Leganés, Madrid) with fever or respiratory tract infection and with positive rhinovirus detection in the nasopharyngeal aspirate samples. Virologic diagnosis was made by multiplex reverse transcription-polymerase chain reaction and for some virus by direct immunofluorescent assay in nasopharyngeal samples. Demographic and clinical data of those patients with rhinovirus infection were described and compared with a group of 86 patients, infected only with RSV, randomly selected from the same population. Results: We detected 85 children admitted to hospital with rhinovirus infection. Rhinovirus was the cause of 25% of all admissions, among the total of 340 under 2-year olds diagnosed with fever or respiratory tract infection. Rhinovirus was the second viral agent identified, after RSV. Clinical diagnosis was recurrent wheezing in 48.2%; bronchiolitis in 36.5%; and pneumonia in 3.5%. Fever was present in 60% of the patients. Radiologic infiltrates were found in 22.4% of the children. In 50.6% of the infants, oxygen saturation under 95% was detected, at the time of admission. Hypoxia was present in RSV-infected children more frequently (P = 0.005). Also, in this group, final diagnosis was, most frequently, bronchiolitis (P = 0.0001), and rhinovirus-infected patients were most frequently males (P = 0.004). Conclusions: Rhinovirus was detected in hospitalized infants with respiratory tract disease and was the second most common virus after RSV. In our experience, it was the second etiologic agent associated with recurrent wheezing in hospitalized children, under the age of 2 years.
Pediatric Infectious Disease Journal | 2010
Cristina Calvo; Inmaculada Casas; María Luz García-García; Francisco Pozo; Noelia Reyes; Nieves Cruz; Luisa García-Cuenllas; Pilar Pérez-Breña
Background: Recently a new genogroup of human rhinovirus (HRV) has been described and named HRV-C. The relative importance of HRV-C in viral respiratory tract illnesses is unknown. Objective: We looked for HRV-C in pediatric patients with respiratory tract infections to determine the incidence of HRV-C and its role in sick and healthy children. We describe the clinical differences associated with HRV-C infections and other HRV genogroups. Patients and Methods: From January 2004 to December 2008, a prospective study was conducted in children younger than 14 years who were admitted with respiratory infection to the Pediatrics Department of the Severo Ochoa Hospital in Madrid, Spain. Specimens of nasopharyngeal aspirate were taken for virologic study with polymerase chain reaction, and clinical data were recorded. HRV specimens were genotyped. We studied the frequency of HRV-C infections, the clinical course of these patients and the differences with other HRV genogroups (HRV-A and HRV-B). Presence of HRV-C was also studied in a group of healthy children. Results: HRV was detected in 424 of 1555 episodes of illness (27.2%) and in 26 of 211 healthy children (12.3%) (P < 0.001). We amplified at random 248 of them (227 hospitalized children and 21 healthy children): 132 (53.2%) had HRV-A, 28 (11.2%) had HRV-B, and 88 (35.4%) HRV-C. HRV-C infections were associated with asthma, recurrent wheezing, and bronchiolitis but were not significantly different from the HRV-A genogroup. Nevertheless, significant clinical differences were observed between the HRV-B genogroup and the other groups: more frequent infiltrate on chest radiograph (P = 0.017), fever (P = 0.052), diagnosis of pneumonia (P = 0.01), and antibiotic treatment (P = 0.004). Conclusions: HRV-C infections were frequent in hospitalized children with respiratory diseases and were associated with asthma, recurrent wheezing, and bronchiolitis. No clinical differences were found with the HRV-A group: HRV-B group had clinical differences with both the other groups.
Archives of Disease in Childhood | 2006
María Luz García-García; Cristina Calvo; F Martín; Pilar Pérez-Breña; B. Acosta; Inmaculada Casas
Background: Human metapneumovirus (hMPV) causes lower respiratory tract infections, particularly in young children and the elderly. Methods: A prospective study was conducted on the clinical characteristics of infants <2 years of age admitted to hospital for respiratory infection and the characteristics of hMPV infections were compared with those of infections caused by respiratory syncytial virus (RSV). Influenza A, B and C viruses, RSV, parainfluenza viruses, and adenoviruses were simultaneously detected in clinical samples by multiple reverse transcription nested-PCR assay. The presence of hMPV was tested in all samples using two separate RT-PCR tests. Results: A respiratory virus was detected in 65.9% of the 749 children included in the study. hMPV, found in 69 of the positive nasopharyngeal aspirates (14%), was the most common virus after RSV. Peak incidence was in March and over 80% of children were <12 months of age. The most common diagnoses were recurrent wheezing (49.3%) and bronchiolitis (46.4%). Oxygen therapy was required by 58% of patients, and assisted ventilation by one. Clinical characteristics in the 18 co-infections were indistinguishable from those of single infections. Fifty one hMPV single infections were compared with 88 hRSV single infections. Recurrent wheezing was diagnosed more frequently in hMPV patients. All other variables tested were similar in both groups. Conclusions: hMPV was the second most frequent virus after RSV in infants <2 years of age hospitalised for respiratory infection and was associated with lower respiratory tract infections. hMPV occurred predominantly in springtime. Co-infections were frequent and clinically similar to single infections and RSV infections.
Pediatric Infectious Disease Journal | 2008
María Luz García-García; Cristina Calvo; Francisco Pozo; Pilar Pérez-Breña; Sergio Quevedo; Teresa Bracamonte; Inmaculada Casas
The main objective of our study was to determine the frequency of human bocavirus (HBoV) detection in asymptomatic children and to compare it with that in children hospitalized because of respiratory infection. HBoV was detected in 5% of 116 healthy children versus 17% of 908 hospitalized children. HBoV can be detected in healthy children but with a significantly lower frequency than in ill children.