Association between nutritional status and dengue severity in Thai children and adolescents.

Most cases of dengue virus infection are mild, but severe cases can be fatal. Therefore, identification of factors associated with dengue severity is essential to improve patient outcomes and reduce mortality. The objective of this study was to assess associations between nutritional status and dengue severity among Thai children and adolescents. This retrospective cross-sectional study was based on the medical records of 355 patients with dengue treated at the Hospital for Tropical Disease (Bangkok, Thailand) from 2017 to 2019. Subjects were Thai children aged less than 18 years with dengue virus infection confirmed by positive NS1 antigen or IgM. The 1997 and 2009 World Health Organization (WHO) dengue classifications were used to define disease severity and body mass index for age while the WHO growth chart was used to classify nutritional status. The proportions of patients with dengue fever who were underweight, normal weight, and overweight were 8.8%, 61.5%, and 29.7%, respectively. The proportions of patients with dengue haemorrhagic fever (DHF) who were underweight, normal weight, and overweight were 10.2%, 66.1%, and 23.7%, respectively. The proportions of patients with non-severe dengue who were underweight, normal weight, and overweight were 8.6%, 60.9%, and 30.5%, respectively; the same proportions of patients with severe dengue were 10.5%, 67.1%, and 22.4%, respectively. Higher proportions of patients with severe plasma leakage (DHF grade III and IV) were overweight compared with those with mild plasma leakage (DHF grade I and II) (45.5% vs. 18.8%). No difference in nutritional status was observed in patients with different dengue severity

Antibody persistence upto 5 years after primary immunization and booster with an inactivated chromatographically purified Vero cell-derived Japanese encephalitis vaccine in Thai children

Japanese encephalitis is the main cause of viral encephalitis in Asia. In a previous single-arm vaccine trial, an inactivated chromatographically purified Japanese encephalitis Vero cell vaccine (CVI-JE; JEVACTM) was safe and immunogenic in 152 Thai children aged 1–3 years receiving a 2-dose primary immunization and booster dose 1 year later. We conducted a 5-year follow-up assessment of the persistence of the immune response the 144 children remaining in this cohort after first booster dose. Immunity was assessed by 50% plaque reduction neutralization test annually for up to 5 years post-booster. Seroprotection rates (95%CI) decreased from 100% (97.1–100) at 1 year post-booster to 93% (85.0–98.3) at 5 years post-booster. No serious vaccine-related adverse events or Japanese encephalitis infections were reported. A 2-dose primary immunization and booster 1 year later with CVI-JE provided long-lasting immunity in the majority of children

Comparison of maternal dengue seroprevalence, maternal and cord sera dengue antibody titers in various articles.

<p>* p-values are based on paired sample t-test</p><p>^a range</p><p>^b mean±SD</p><p>^c mg/dL, GMT (range)</p><p>^d p-value 0.002 for DEN-1, 0.003 for DEN-3 and <0.001 for DEN-2 and DEN-4</p><p>^e p-value <0.001 for DEN-2 and DEN-3 only, p-value for DEN-1 and DEN-4 ≥ 0.5</p><p><i>n/a</i> = not applicable, <i>n</i>.<i>d</i>. <i>=</i> no data available</p><p>Comparison of maternal dengue seroprevalence, maternal and cord sera dengue antibody titers in various articles.</p

Neutralizing Dengue Antibody in Pregnant Thai Women and Cord Blood

<div><p>Background</p><p>The WHO ‘Global Strategy for Dengue Prevention and Control, 2012–2020’ addresses the growing need for the treatment of dengue, and targets a 25% reduction in morbidity and 50% in mortality (using 2010 estimates as baseline). Achieving these goals requires future dengue prevention strategies that will employ both potential vaccines and sustainable vector-control measures. Maternally transferred dengue antibody is an important factor in determining the optimal age for dengue vaccination.</p><p>Objectives</p><p>To estimate the seroprevalence of dengue antibodies among mothers living in an area of high endemicity – Ban Pong, Ratchaburi Province – and to assess maternal dengue antibodies transferred to cord blood.</p><p>Materials & Methods</p><p>A cross-sectional study was conducted with 141 pregnant women who delivered at Ban Pong Hospital, Ratchaburi, Thailand. Maternal-cord paired sera were tested for dengue neutralizing (NT) antibody by PRNT₅₀ assay. A ratio of ≥ 1:10 NT titer to dengue serotype was considered seropositive.</p><p>Results</p><p>Most mothers (137/141, 97.2%) had NT antibodies to at least one dengue serotype in their sera. At birth, the proportion of cord sera with NT antibodies to DEN-1, DEN-2, DEN-3, and DEN-4, were high and similar to the sera of their mothers, at 93.6%, 97.2%, 97.9%, and 92.2%, respectively. The dengue geometric mean titers (GMT) in cord blood were significantly higher than the maternal antibodies (p<0.001): highest in DEN-2, followed by DEN-3, and then DEN-1. The GMT of DEN-4 was the lowest among all four serotypes.</p><p>Conclusions</p><p>Dengue infection is highly prevalent among pregnant women in this dengue-endemic area. Most of the cord blood had transferred dengue antibodies, which may have an impact on the disease burden in this population.</p></div

Immunogenicity and safety of inactivated chromatographically purified Vero cell-derived Japanese encephalitis vaccine in Thai children

Summary: Inactivated mouse-brain-derived Japanese encephalitis vaccine has a worrisome safety profile and the live attenuated vaccine is unsuitable in immunodeficiency. This study aimed to evaluate the immunogenicity and safety of an inactivated chromatographically purified Vero-cell-derived JE vaccine (CVI-JE, Beijing P-3 strain) in children. 152 healthy Thai children, with an average (SD) age of 14.4 (3.8) months, received 3 doses of CVI-JE on days 0, 7–28, and one year. Homologous JE neutralizing antibody titers (NT) were measured. All subjects had seroprotection [geometric mean titer (GMT) 150] 28 days' post 2nd vaccination. The seroprotection rates at 1 year after primary series and and 1 month after the booster were 89.3% (GMT 49) and 100% (GMT 621), respectively. Local and systemic reactions–fever (17.6%), vomiting (8%), and poor appetite (5.3%)–were noted within 28 days' post-vaccination. All these symptoms were self-limited. Conclusions: CVI-JE is safe, immunogenic, and provided high NT

The proportion and geometric mean titer of NT dengue antibodies of 141 maternal and cord paired sera.

<p>Note: p-values for comparisons of seroprevalence are based on symmetry test; p-values for comparisons of GMTs between mother and cord are based on paired test of log (NT)</p><p>The proportion and geometric mean titer of NT dengue antibodies of 141 maternal and cord paired sera.</p

Correlation between maternal and cord blood of DEN-1 to DEN-4 neutralizing antibodies titers.

<p>X-axis shows GMTs of cord blood dengue antibody and Y-axis shows GMTs of maternal dengue antibody of DEN-1, DEN-2, DEN-3 and DEN-4. The Spearman’s rho of DEN1, DEN2, DEN3 and DEN4 are 0.90, 0.92, 0.88 and 0.89 respectively.</p