Detection of dengue cases by serological testing in a dengue vaccine efficacy trial: Utility for efficacy evaluation and impact of future vaccine introduction

Long-term immunogenicity and safety of tetravalent dengue vaccine (CYD-TDV) in healthy populations in Singapore and Vietnam: 4-year follow-up of randomized, controlled, phase II trials

“…However, two of these cases were only serologically confirmed, which lacks specificity and bias towards false positives in CYD-TDV recipients. 23 These participants could have been seronegative at baseline, but as the influence of pre-vaccination serostatus was not part of the original study design, the serostatus of these participants with serologically confirmed cases was not assessed. It was not part of the original study design to split immunogenicity data by immune versus naïve, so performing sub-analyses based on pre-vaccination serostatus was not possible.…”

Vaccine Update: Recent Progress With Novel Vaccines, and New Approaches to Safety Monitoring and Vaccine Shortage

“…Serologic assays are used more widely but can lead to false-positive results during postvaccination surveillance. 42 With most surveillance unable to detect every dengue case, the capacity to monitor program baseline rates and the success of disease prevention remains limited.…”

Rapid and accurate interpretation of dengue diagnostics in the context of dengue vaccination implementation: Viewpoints and guidelines issued from an experts group consultation

“… a Several factors may generate possible suboptimal detection of NS1 (see text) b Asymptomatic or missed dengue infection occurring less than 3 months before testing c Residual dengue IgM elicited by CYD-TDV may last at least 2 months [ 4 ] d Flavivirus cross-reactive antibodies (in secondary infection) Abbreviations: DPO, days post onset; IgM, immunoglobin M; Pos, Positive result; Neg, Negative result; Pos/Neg, the sensitivity of the test, the time point of serum sampling, and the serological status of the patient may affect the result …”

“…The vaccine clinical monitoring and careful diagnosis of the vaccinated and unvaccinated populations enrolled in these studies have provided valuable information that is useful for the later stage of vaccination implementation and its monitoring [ 2 ]. A recent study of the validity of the serological diagnosis of dengue immunoglobulin G (IgG) and immunoglobulin M (IgM) by ELISA according to WHO recommendations [ 3 ] in acute febrile and in convalescent individuals vaccinated and unvaccinated (Placebo), and virologically confirmed or not, showed a high sensitivity (97.1%) but a low specificity (85.1%) in the IgM ELISA due to the presence of residual IgM from previous vaccination or subclinical undetected dengue, which may introduce a diagnostic bias [ 4 ]. The proportion of false positives IgM in the CYD-TDV vaccinated group (17.4%) was higher than in the control group (10.1%), particularly within the 2 months following vaccination.…”