[Show abstract][Hide abstract] ABSTRACT: The aim of the European Sero-Epidemiology Network 2 (ESEN2) project was to estimate age-specific seroprevalence for a number of vaccine-preventable diseases in Europe. To achieve this serosurveys were collected by 22 national laboratories. To adjust for a variety of laboratory methods and assays, all quantitative results were transformed to a reference laboratory's units and were then classified as positive or negative to obtain age-specific seroprevalence. The aim of this study was to assess the value of standardization by comparing the crude and standardized seroprevalence estimates. Seroprevalence was estimated for measles, mumps, rubella, diphtheria, varicella zoster and hepatitis A virus (HAV) and compared before and after serological results had been standardized. The results showed that if no such adjustment had taken place, seroprevalence would have differed by an average of 3·2% (95% bootstrap interval 2·9–3·6) although this percentage varied substantially by antigen. These differences were as high as 16% for some serosurveys (HAV) which means that standardization could have a considerable impact on seroprevalence estimates and should be considered when comparing serosurveys performed in different laboratories using different assay methods.
Epidemiology and Infection 11/2014; Epidemiol. Infect.(25):1-10. · 2.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Immunoblot (IB) techniques using different Epstein-Barr virus (EBV) antigens have been applied for detecting specific antibodies, making possible to obtain EBV seroprofiles in a single determination. The aim of this study was to evaluate a commercial IB for the detection of EBV-specific IgG (Euroimmun, Lübeck, Germany).
A total of 117 samples classified as EBV primary recent infections (n = 70), past infections (n = 29), or not infected (n = 18) have been used. The samples were characterized by immunofluorescence, by testing EBV capsid antigens IgM and IgG (using indirect approaches) and EBV nuclear antigen (by anticomplement technique; Meridian Bioscience Inc.).
Using the cut-off value as defined by the IB manufacturer, the concordance, relative sensitivity, and relative specificity were 85.5 (100/117), 94.3% (66/70), and 72.3% (34/47), respectively. If a corrected cut-off value was considered to classify the samples, the corresponding corrected figures were 89.7, 88.6, and 91.5%, respectively.
Being a useful serological diagnostic tool, IB for testing EBV IgG seems to be an adequate approach to define EBV seroprofiles. However, efforts to better define the cut-off value should be made in order to improve the performance of the assay in evaluation.
Journal of Clinical Laboratory Analysis 03/2014; · 1.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mumps virus (MuV) was detected in the cerebrospinal fluid (CSF) of 6 of 158 patients with meningitis or encephalitis in absence of clinical mumps in the context of mumps epidemics. Our results suggest the need for the study of MuV RNA in the CSF of neurological patients in this context.
Diagnostic microbiology and infectious disease 03/2014; · 2.45 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: : Study Design: Case report.Objective: To report this rare Varicella Zoster Virus (VZV) complication in a multiple sclerosis patient.Summary of Background Data: Longitudinally extensive transverse myelitis (LETM) is a spinal cord lesion that extends over 3 or more vertebral segments. A common feature in neuromyelitis optica, LETM can also occur in several other diseases.Methods: A 15 year-old boy with relapsing-remitting Multiple Sclerosis, who has been treated with immunomodulators for 6 months, developed a subacute left brachio-crural hemiparesis with ipsilateral decreased sensation in the trunk and limbs. This was interpreted as a new relapse, and was treated consequently. During the evolution, the patient developed a cutaneous rash in the left C8 metameres followed by asymmetric tetraparesis.Results: MRI demonstrated an extensive cervical-thoracic medullar lesion. Cerebrospinal fluid (CSF) analysis revealed 17 leukocytes /μL (95% mononuclear), protein 41 mg/dL, negative VZV-DNA by polymerase chain reaction, but elevated anti-VZV IgG CSF/serum index, with a normal albumin CSF/serum index, all of which were consistent with intrathecal synthesis of anti-VZV antibody. We were able to rule out all other causes included in the differential diagnosis, namely, vascular disease, tumor, and autoimmune conditions, especially those associated with NMO spectrum disorders.Conclusions: Awareness of the potentially varied presentation of VZV myelitis can enable earlier recognition and specific treatment.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate enzyme immunoassays (EIA) (Euroimmun, Lübeck, Germany) and chemiluminiscent immunoassays (CLIA) (Diasorin, Saluggia, Italy) in their application to detect B19V-IgM and -IgG. For this purpose, one hundred and ninety samples were studied. Of them, 101 came from recent infection cases (B19V-specific IgM (86) and/or PCR (87), 42 from past infections, 18 from non-infected, and 29 from other viral recent infections (Epstein-Barr virus, measles, and rubella). Samples were characterized by capture (for IgM), or indirect (for IgG) EIA (Biotrin, Dublin, Ireland); indeterminate samples were classified by indirect immunofluorescence (IIF) (Biotrin). All the samples were used for testing IgM assays, and all but the cases from other viral infections were used for IgG tests. For IgM, CLIA, and EIA identified 76 and 62 of 86 IgM positives, respectively (sensitivity 88.4% and 72.1%). Considering B19V IgM negative samples, negative result was obtained in 95 and 92 of 104, being the specificity values of CLIA and EIA 91.3% and 88.5%, respectively. For IgG, CLIA and EIA identified correctly 114 and 115 of the 122 positive samples (sensitivity 93.4% and 94.3%, respectively), and 39 and 36 of 39 negative samples (specificity 100% and 92.3%). As conclusion, CLIA methods can be used in clinical laboratories as adequate alternatives to the well-established Biotrin EIAs.
[Show abstract][Hide abstract] ABSTRACT: Abstract Toscana virus (TOSV), an arthropod-borne phlebovirus, is an important agent of acute meningitis and meningoencephalitis in the Mediterranean area. The epidemiology of the infection in humans in Catalonia is at present unknown. In this study, we found a seroprevalence of infection of 6%, and 2 clinical cases were detected by serology and/or PCR.
[Show abstract][Hide abstract] ABSTRACT: Objectives
To describe the prevalence of influenza-like syndrome in winter 2009 and the factors associated with its occurrence.MethodsA cross-sectional study was carried out in 18 hospitals in Spain. Volunteers completed a health questionnaire in which they reported the occurrence of influenza-like syndrome and vaccination and demographic status.ResultsA total of 1,289 healthcare workers participated. Of these, 72 (5.6%) reported influenza in their family, 195 (15.1%) had been vaccinated against the A/California/7/2009/H1N1 virus and 75 (5.8%, 95%CI: 4.5-7.1%) had been diagnosed with influenza like-syndrome. There were differences among regions. In logistic regression analysis, the following factors were associated with a higher prevalence of influenza-like syndrome: working in Madrid (OR = 8.31, 95%CI: 1.05-65.39), the occurrence of cases of influenza in the family (OR = 2.84, 95%CI: 1.41-5.73) and not having been vaccinated against influenza A (H1N1) (OR = 2.68, 95% CI: 1.05-6.82).Conclusions
Differences in the prevalence of influenza-like syndrome were due to the occurrence of familiar cases and region. Vaccination against influenza A (H1N1) was associated with a lower prevalence of the disease.
[Show abstract][Hide abstract] ABSTRACT: Enzyme linked fluorescent assays (VIDAS EBV VCA IgM, VIDAS EBV VCA/EA IgG and VIDAS EBV EBNA IgG (Biomérieux, France) were evaluated to determine markers for infection of Epstein Barr virus, as well as to establish antibody profiles, compared with immunofluorescence assays as reference. The assays evaluated showed good values for sensitivity, specificity and agreement, making them useful for their application in clinical laboratories.
Enfermedades Infecciosas y Microbiología Clínica 07/2012; · 1.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Mumps outbreaks have recently been recorded in a number of highly vaccinated populations. We related seroprevalence, epidemiological and vaccination data from 18 European countries participating in The European Sero-Epidemiology Network (ESEN) to their risk of mumps outbreaks in order to inform vaccination strategies. Samples from national population serum banks were collected, tested for mumps IgG antibodies and standardized for international comparisons. A comparative analysis between countries was undertaken using age-specific mumps seroprevalence data and information on reported mumps incidence, vaccine strains, vaccination programmes and vaccine coverage 5-12 years after sera collection. Mean geometric mumps antibody titres were lower in mumps outbreak countries [odds ratio (OR) 0·09, 95% confidence interval (CI) 0·01-0·71)]. MMR1 vaccine coverage ⩾95% remained protective in a multivariable model (P<0·001), as did an interval of 4-8 years between doses (OR 0·08, 95% CI 0·01-0·85). Preventing outbreaks and controlling mumps probably requires several elements, including high-coverage vaccination programmes with MMR vaccine with 4-8 years between doses.
Epidemiology and Infection 06/2012; · 2.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Our aim was to study the proportion of healthcare workers with a positive serology for Influenza A(H1N1)2009 without having flu, in a Spanish hospital at the beginning of the pandemic.
A survey study carried out during August 2009 (before the peak of the pandemic in Spain) in the Hospital Costa del Sol, a second level hospital with almost 300 beds in the South of Spain. The participants were workers in the following hospital units: Emergencies, Medical Area (Internal Medicine, Chest Diseases), Surgical Area (General Surgery and Anaesthesia) of any professional category. A study was made of the proportion of healthcare workers in our hospital with positive serology for the new influenza A (H1N1)2009 virus, as determined by the haemagglutination inhibition technique (≥1/40). The subjects completed a health status questionnaire, and provided a blood sample for serology testing.
A total of 239 workers participated, of whom 25.1% had positive serology. The hospital area in which most individuals had positive serology was the Emergency Department (36.6%), while the professional category in which most individuals with a positive serology worked was that of the orderlies (41.7%).
Around 25% of healthcare workers in our hospital had positive serology before the peak of the pandemic, none of them had received vaccine for Influenza A (H1N1) 2009 or had been diagnosed of influenza previously.
[Show abstract][Hide abstract] ABSTRACT: IgM detection is considered as the gold standard for mumps diagnosis. Currently, most cases in developed countries occur in highly vaccinated populations due to secondary vaccine failure. In these patients, pre-existing vaccine-induced antibodies are not able to neutralise the virus, but prevent the typical primary response, so that specific IgM is not always elicited. Consequently, acute infection has to be demonstrated by direct detection of the virus by viral isolation or genomic amplification. RT-PCR allows a diagnosis with the maximum sensitivity to be made and also forms the basis for genotype characterisation by sequencing the SH gene, according to WHO recommendations. However, none of the RT-PCR techniques properly evaluated for the diagnosis of acute mumps infection yields an amplification fragment useful for genotyping, and none of the amplification techniques described for genotyping has proved to be sensitive enough for diagnosis.
Development of a RT-PCR for the mumps virus diagnosis and genotyping, properly evaluated in comparison with serological gold-standard technique.
195 suspected mumps cases and six wild type MuV genotypes were studied.
Our method was able to detect 0.001 TCID(50) of mumps virus. Fifty-eight of these showed positive results, of which 54 (93.3%) showed mumps RNA in saliva, while only 20 (34.5%) had mumps IgM in serum. Genotypes G1, G2, H1, H2, D1 and C were identified in positive samples.
The technique described could be a very useful tool for mumps surveillance, management and control.
Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 12/2011; 52(4):359-62. · 3.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain.
[Show abstract][Hide abstract] ABSTRACT: The association between respiratory viruses and myocarditis has hardly ever been described. We report a case of acute myocarditis in an immunocompetent child associated with the presence of parainfluenza virus type 3 infection, in a context of recent influenza illness, confirmed by molecular and serological studies.
Journal of clinical microbiology 03/2011; 49(5):2072-3. · 4.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To compare the performance of four diagnostic commercial systems for Epstein-Barr virus (EBV) serology (for IgM and IgG virus capsid antigen [VCA] and EBV nuclear antigen [EBNA] antibodies), a collection of 125 samples from clinically suspected infectious mononucleosis cases was studied. Indirect immunofluorescence (IIF) for VCA IgM and IgG antibodies and anticomplement immunofluorescence for EBNA antibodies (Meridian Bioscience Inc.) were used as reference methods. By these methods, the cases were classified EBV primary infection (presence of IgM to VCA or IgG to VCA in the absence of EBNA antibodies; n = 82), EBV past infection (presence of VCA IgG and EBNA antibodies in the absence of VCA IgM; n = 26), or no infection (negative for the three markers; n = 17). The following systems were tested: two chemiluminescent immunoassays (CLIAs; the Liason [CLIA-L; DiaSorin] and the Immulite 2000 [CLIA-I; Siemens]), immunofiltration (IF; All.Diag), and an enzyme-linked immunosorbent assay (ELISA; DiaSorin). In the IgM assays, sensitivities ranged from 67.1% (ELISA) to 92.2% (CLIA-L) and specificities ranged from 93.8% (CLIA-L) to 100% (IF). In the VCA IgG assays, sensitivities varied from 79.4% (IF) to 94.4% (CLIA-I) and specificities varied from 94.4% (IF and CLIA-L) to 100% (CLIA-I and ELISA). In EBNA assays, sensitivities ranged from 78.1% (IF) to 93.8% (CLIA-I) and specificities ranged from 32.3% (CLIA-L) to 91.4% (IF). In relation to EBV profiles, the corresponding figures for sensitivity (in detecting primary infection) for IF, CLIA-L, CLIA-I, and ELISA were 92.7%, 93.8%, 89%, and 89.6%, respectively, and those for specificity (to exclude primary recent infection) were 90.7%, 94.6%, 97.7%, and 95.2%, respectively. Although there were limitations in some individual markers, especially CLIA-L for EBNA IgG, the systems evaluated appear to be useful for diagnosis of EBV infection.
[Show abstract][Hide abstract] ABSTRACT: A new member of the phlebovirus genus, tentatively named Granada virus, was detected in sandflies collected in Spain. By showing the presence of specific neutralizing antibodies in human serum collected in Granada, we show that Granada virus infects humans. The analysis of the complete genome of Granada virus revealed that this agent is likely to be a natural reassortant of the recently described Massilia virus (donor of the long and short segments) with a yet unidentified phlebovirus (donor of the medium segment).
The American journal of tropical medicine and hygiene 10/2010; 83(4):760-5. · 2.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although the WHO recommends the use of genotyping as a tool for epidemiological surveillance for mumps, limited data on mumps virus (MV) genotype circulation that may be used to trace the patterns of virus spread are available. We describe the first complete series of data from Spain. The small hydrophobic region was sequenced from 237 MV-positive samples from several regions of Spain collected between 1996 and 2007. Six different genotypes were identified: A, C, D (D1), G (G1, G2), H (H1, H2), and J. Genotype H1 was predominant during the epidemic that occurred from 1999 to 2003 but was replaced by genotype G1 as the dominant genotype in the epidemic that occurred from 2005 to 2007. The same genotype G1 strain caused concomitant outbreaks in different parts of the world (the United States, Canada, and the United Kingdom). The remaining genotypes (genotypes A, C, D, and J) appeared in sporadic cases or small limited outbreaks. This pattern of circulation seems to reflect continuous viral circulation at the national level, despite the high rates of vaccine coverage.
Journal of clinical microbiology 04/2010; 48(4):1245-54. · 4.16 Impact Factor