20 research outputs found
Seasonality, age, gender and general clinical and laboratory profile of Cases and Controls.
<p>Seasonality, age, gender and general clinical and laboratory profile of Cases and Controls.</p
Pattern of illnesses in febrile children with differentiated fever.
<p>Pattern of illnesses in febrile children with differentiated fever.</p
Pattern of infections in children with undifferentiated fever.
<p>Pattern of infections in children with undifferentiated fever.</p
Prevalence of undifferentiated fever and contribution of LVD and malaria parasitaemia to undifferentiated fever in Cases with febrile versus non-febrile convulsions.
<p>Prevalence of undifferentiated fever and contribution of LVD and malaria parasitaemia to undifferentiated fever in Cases with febrile versus non-febrile convulsions.</p
Presenting features in children with LVD versus children with other infections.
<p>Presenting features in children with LVD versus children with other infections.</p
Association between the prevalence of LVD and age, gender, season, and clinical status on presentation.
<p>Association between the prevalence of LVD and age, gender, season, and clinical status on presentation.</p
Development and evaluation of antibody-capture immunoassays for detection of Lassa virus nucleoprotein-specific immunoglobulin M and G
<div><p>Background</p><p>The classical method for detection of Lassa virus-specific antibodies is the immunofluorescence assay (IFA) using virus-infected cells as antigen. However, IFA requires laboratories of biosafety level 4 for assay production and an experienced investigator to interpret the fluorescence signals. Therefore, we aimed to establish and evaluate enzyme-linked immunosorbent assays (ELISA) using recombinant Lassa virus nucleoprotein (NP) as antigen.</p><p>Methodology/Principal findings</p><p>The IgM ELISA is based on capturing IgM antibodies using anti-IgM, and the IgG ELISA is based on capturing IgG antibody–antigen complexes using rheumatoid factor or Fc gamma receptor CD32a. Analytical and clinical evaluation was performed with 880 sera from Lassa fever endemic (Nigeria) and non-endemic (Ghana and Germany) areas. Using the IFA as reference method, we observed 91.5–94.3% analytical accuracy of the ELISAs in detecting Lassa virus-specific antibodies. Evaluation of the ELISAs for diagnosis of Lassa fever on admission to hospital in an endemic area revealed a clinical sensitivity for the stand-alone IgM ELISA of 31% (95% CI 25–37) and for combined IgM/IgG detection of 26% (95% CI 21–32) compared to RT-PCR. The specificity of IgM and IgG ELISA was estimated at 96% (95% CI 93–98) and 100% (95% CI 99–100), respectively, in non-Lassa fever patients from non-endemic areas. In patients who seroconverted during follow-up, Lassa virus-specific IgM and IgG developed simultaneously rather than sequentially. Consistent with this finding, isolated IgM reactivity, i.e. IgM in the absence of IgG, had no diagnostic value.</p><p>Conclusions/Significance</p><p>The ELISAs are not equivalent to RT-PCR for early diagnosis of Lassa fever; however, they are of value in diagnosing patients at later stage. The IgG ELISA may be useful for epidemiological studies and clinical trials due its high specificity, and the higher throughput rate and easier operation compared to IFA.</p></div
Clinical performance characteristics of the IgM ELISA as stand-alone test and in combination with the IgG ELISA for early diagnosis of Lassa fever.
<p>Clinical performance characteristics of the IgM ELISA as stand-alone test and in combination with the IgG ELISA for early diagnosis of Lassa fever.</p
IgM and IgG ELISA results in patients grom various settings.
<p>IgM and IgG ELISA results in patients grom various settings.</p
Sample-to-cut-off (S/CO) values for 880 sera tested in IgM ELISA, RF-based IgG ELISA, and CD32-based IgG ELISA and comparison with IFA results.
<p>The S/CO values obtained with the ELISA are shown as histograms according to sample origin, type of ELISA, and IFA results. The cut-offs for the ELISAs are indicated by vertical dotted lines. The number of samples with OD < CO and OD > CO is indicated in left and right corner, respectively, of each diagram.</p