Dengue Serotype Differences in Urban and Semi-rural Communities in Ecuador

Dengue is a major vector-borne infection causing large outbreaks in urban communities in tropical regions. During the period 2010- 2014; 434 serum samples from febrile patients were collected from a  semi-rural community hospital located in the norwestern region of Ecuador. Dengue virus (DENV) was investigated by reverse transcriptase PCR; a total of 48 samples were positive for dengue. During our study we detected  DENV-2 and DENV-3 from 2010 to 2013 and the four  DENV  serotypes during the period 2013-2014.  Surprisingly, our results contrasted with surveys carried out in urban centers throughout the  Ecuadorian Coast in which  DENV-1, DENV-2 and DENV-4 were prevalent during years 2010-2013 and only 2 serotypes  (DENV-1 and DENV-2) in 2014.These results suggest  that dengue viruses in semi-rural communities didn’t  originate in the Ecuadorian cities.  &nbsp

Integration of Information Technologies in Clinical Studies in Nicaragua

The authors report their experience of integrating information technologies in clinical and epidemiological studies of dengue infection in Nicaragua

From Construction Workers to Architects: Developing Scientific Research Capacity in Low-Income Countries

Solving global health challenges in a sustainable manner depends on explicitly addressing scientific capacity-building needs, as well as establishing long-term, meaningful partnerships with colleagues in the developing world

Preventing Dengue Epidemics during the COVID-19 Pandemic.

No abstract available

Adapting Rapid Diagnostic Tests to Detect Historical Dengue Virus Infections.

The only licensed dengue vaccine, Dengvaxia®, increases risk of severe dengue when given to individuals without prior dengue virus (DENV) infection but is protective against future disease in those with prior DENV immunity. The World Health Organization has recommended using rapid diagnostic tests (RDT) to determine history of prior DENV infection and suitability for vaccination. Dengue experts recommend that these assays be highly specific (≥98%) to avoid erroneously vaccinating individuals without prior DENV infection, as well as be sensitive enough (≥95%) to detect individuals with a single prior DENV infection. We evaluated one existing and two newly developed anti-flavivirus RDTs using samples collected >6 months post-infection from individuals in non-endemic and DENV and ZIKV endemic areas. We first evaluated the IgG component of the SD BIOLINE Dengue IgG/IgM RDT, which was developed to assist in confirming acute/recent DENV infections (n=93 samples). When evaluated following the manufacturer's instructions, the SD BIOLINE Dengue RDT had 100% specificity for both non-endemic and endemic samples but low sensitivity for detecting DENV seropositivity (0% non-endemic, 41% endemic). Sensitivity increased (53% non-endemic, 98% endemic) when tests were allowed to run beyond manufacturer recommendations (0.5 up to 3 hours), but specificity decreased in endemic samples (36%). When tests were evaluated using a quantitative reader, optimal specificity could be achieved (≥98%) while still retaining sensitivity at earlier timepoints in non-endemic (44-88%) and endemic samples (31-55%). We next evaluated novel dengue and Zika RDTs developed by Excivion to detect prior DENV or ZIKV infections and reduce cross-flavivirus reactivity (n=207 samples). When evaluated visually, the Excivion Dengue RDT had sensitivity and specificity values of 79%, but when evaluated with a quantitative reader, optimal specificity could be achieved (≥98%) while still maintaining moderate sensitivity (48-75%). The Excivion Zika RDT had high specificity (>98%) and sensitivity (>93%) when evaluated quantitatively, suggesting it may be used alongside dengue RDTs to minimize misclassification due to cross-reactivity. Our findings demonstrate the potential of RDTs to be used for dengue pre-vaccination screening to reduce vaccine-induced priming for severe dengue and show how assay design adaptations as well quantitative evaluation can further improve RDTs for this purpose