Health-Related Quality of Life after Dengue Fever, Morelos, Mexico, 2016-2017

An economic evaluation of implementing a decentralized dengue screening intervention under the National Vector Borne Disease Control Programme in Tamil Nadu, South India

Background

Lack of effective early screening is a major obstacle for reducing the fatality rate and disease burden of dengue. In light of this, the government of Tamil Nadu has adopted a decentralized dengue screening strategy at the primary healthcare (PHC) facilities using blood platelet count. Our objective was to determine the cost-effectiveness of a decentralized screening strategy for dengue at PHC facilities compared with the current strategy at the tertiary health facility (THC) level.

Methods

Decision tree analysis followed a hypothetical cohort of 1000 suspected dengue cases entering the model. The cost-effectiveness analysis was performed at a 3% discount rate for the proposed and current strategy. The outcomes are expressed in incremental cost-effectiveness ratios (ICERs) per quality-adjusted life years gained. One-way sensitivity analysis and probabilistic sensitivity analysis were done to check the uncertainty in the outcome.

Results

The proposed strategy was found to be cost-saving and ICER was estimated to be −41 197. PSA showed that the proposed strategy had a 0.84 probability of being an economically dominant strategy.

Conclusions

The proposed strategy is cost-saving, however, it is recommended to consider optimal population coverage, costs to economic human resources and collateral benefits of equipment.

Analysis of Neutralizing Antibodies as a Correlate of Instantaneous Risk of Hospitalized Dengue in Placebo Recipients of Dengue Vaccine Efficacy Trials

BACKGROUND

In the CYD14 (NCT01373281) and CYD15 (NCT01374516) dengue vaccine efficacy trials, Month 13 neutralizing antibody (nAb) titers correlated inversely with risk of symptomatic, virologically confirmed dengue (VCD) between Month 13 (one month post-final-dose) and Month 25. We assessed nAb titer as a correlate of instantaneous risk of hospitalized VCD (HVCD), for which participants were continually surveilled for 72 months.

METHODS

Using longitudinal nAb titers from the per-protocol immunogenicity subsets, we estimated hazard ratios (HRs) of HVCD by current nAb titer value for three correlate/endpoint pairs: average titer across all four serotypes/HVCD of any serotype (HVCD-Any), serotype-specific titer/homologous HVCD, and serotype-specific titer/heterologous HVCD.

RESULTS

Baseline-seropositive placebo recipients with higher average titer had lower instantaneous risk of HVCD-Any in 2-16-year-olds and in 9-16-year-olds (HR 0.26 or 0.15 per 10-fold increase in average titer by two methods, 95% CIs 0.14 to 0.45 and 0.07 to 0.34, respectively) pooled across both trials. Results were similar for homologous HVCD. There was evidence suggesting increased HVCD-Any risk in participants with low average titer (1:10 to 1:100) compared to seronegative participants (HR 1.85, 95% CI 0.93 to 3.68).

CONCLUSIONS

Natural infection-induced nAbs were inversely associated with hospitalized dengue, upon exceeding a relatively low threshold.

Cost of Dengue Illness in Indonesia across Hospital, Ambulatory, and not Medically Attended Settings

Informed decisions concerning emerging technologies against dengue require knowledge about the disease’s economic cost and each stakeholder’s potential benefits from better control. To generate such data for Indonesia, we reviewed recent literature, analyzed expenditure and utilization data from two hospitals and two primary care facilities in Yogyakarta city, and interviewed 67 dengue patients from hospital, ambulatory, and not medically attended settings. We derived the cost of a dengue episode by outcome, setting, and the breakdown by payer. We then calculated aggregate Yogyakarta and national costs and 95% uncertainty intervals (95% UIs). Dengue costs per nonfatal case in hospital, ambulatory, not medically attended, and overall average settings were US$316.24 (95% UI: $242.30–$390.18), US$22.45 (95% UI: $14.12–$30.77), US$7.48 (95% UI: $2.36–$12.60), and US$50.41 (95% UI: $35.75–$65.07), respectively. Costs of nonfatal episodes were borne by the patient’s household (37%), social contributors (relatives and friends, 20%), national health insurance (25%), and other sources (government, charity, and private insurance, 18%). After including fatal cases, the average cost per episode became $90.41 (95% UI: $72.79–$112.35). Indonesia had an estimated 7.535 (95% UI: 1.319–16.513) million dengue episodes in 2017, giving national aggregate costs of $681.26 (95% UI: $232.28–$2,371.56) million. Unlike most previous research that examined only the formal medical sector, this study included the estimated 63% of national dengue episodes that were not medically attended. Also, this study used actual costs, rather than charges, which generally understate dengue’s economic burden in public facilities. Overall, this study found that Indonesia’s aggregate cost of dengue was 73% higher than previously estimated, strengthening the need for effective control.

Evaluating the validity of dengue clinical-epidemiological criteria for diagnosis in patients residing in a Brazilian endemic area

BACKGROUND

We evaluated the validity of clinical diagnosis compared with laboratory diagnosis of dengue in a retrospective sample of patients in São José do Rio Preto, Brazil.

METHODS

Our sample included 148 299 clinically (56.3%) or laboratory-diagnosed (43.7%) dengue cases. We compared the sensitivity, specificity, positive and negative predictive value (PPV and NPV) of dengue patients' demographic and clinical characteristics with laboratory-based diagnosis. We used logistic regressions to estimate the correlation between clinical and laboratory diagnosis of dengue and a full set of dengue signs and symptoms.

RESULTS

We found substantial variability in sensitivity and specificity of signs and symptoms ranging from 0.8-81.1 and 21.5-99.6, respectively. Thrombocytopenia exhibited the highest PPV (92.0) and lowest NPV (42.2) and was the only symptom showing agreement with laboratory-confirmed dengue (φ = 0.38). The presence of exanthema and thrombocytopenia led to a greater likelihood of concordant clinical and laboratory diagnoses (exanthema: OR: 4.23; 95% CI: 2.09 to 8.57; thrombocytopenia: OR: 4.02; 95% CI: 1.32 to 12.27).

CONCLUSIONS

We found substantial variation in sensitivity, specificity, PPV and NPV of dengue signs and symptoms. For accuracy, clinical and laboratory diagnosis of dengue should be performed concurrently. When laboratory tests are not available, we suggest focusing on the clinical manifestations most associated with dengue.