Roadmap for the Introduction of a New Dengue Vaccine

Dengue remains the most common vector-transmitted disease in the world despite enormous prevention and control efforts by endemic countries and regions. Today, after decades of research, public health programs contemplate as part of the intervention to control the disease, a safe and effective vaccine against dengue. In this chapter, we review general principles for developing a safe and efficacious vaccine against dengue virus, the current vaccine candidates approved and under research, and the roadmap for the introduction of a new dengue vaccine, based on the procedures, carried out by Mexico, for the licensure and eventual adoption of CYD-TDV vaccine, which concluded with Mexico becoming the first country in the world to grant licensure to a Dengue vaccine in December of 2015. Finally, we discuss the rationale for the adoption of dengue vaccines a public health policy and the paradigm shift required for the efficient adoption of vaccines in low- and middle-income countries

Dengue Fever - a Resilient Threat in the Face of Innovation

For over 70 years, dengue fever has challenged health systems in every region of the World. It has evolved from a benign febrile illness from the tropics to a major concern in urban settlements, overwhelming health infrastructure with large outbreaks, as it continues to teach us important lessons with its complexities. This book intends to review the latest updates on dengue fever, the tools available for its study and control, and promising technologies currently in the pipeline. With this work, the editors wish to provide students with an updated reference text on the basics of this disease as well as researchers and academics, with a useful document to understand the current outlook and the perspectives for the future

Public Health and Economic Benefits of Influenza Vaccination of the Population Aged 50 to 59 Years without Risk Factors for Influenza Complications in Mexico: A Cross-Sectional Epidemiological Study

The Mexican influenza vaccination program does not include a recommendation for people aged 50–59 years without risk factors for influenza complications, and there are limited data regarding the cost-effectiveness of vaccinating this population. To explore the clinical and economic effects of including this population in the vaccination schedule, we performed a cross-sectional epidemiological study using records (2009–2018) from Mexico’s Influenza Surveillance System (SISVEFLU), death records (2010–2015) from the National Mortality Epidemiological and Statistical System, and discharge and hospitalization records (2010–2015) from the Automated Hospital Discharge System databases. A 1-year decision-analytic model was used to assess cost-effectiveness through a decision-tree based on data from SISVEFLU. The primary outcome was influenza cases avoided; with associated influenza-related events as secondary outcomes. Including the population aged 50–59 years without risk factors in Mexico’s influenza immunization program would have resulted in 199,500 fewer cases; 67,008 fewer outpatient consultations; 33,024 fewer emergency room consultations; 33,091 fewer hospitalizations; 12 fewer deaths. These reductions equate to a substantial public health benefit as well as an economic benefit; yielding net savings of 49.8 million US dollars over a typical influenza season. Expansion of the current Mexican vaccination schedule to include these people would be a cost-saving and dominant strategy

A Call for a Reform of the Influenza Immunization Program in Mexico: Epidemiologic and Economic Evidence for Decision Making

Limited information is available to determine the effectiveness of Mexico’s national influenza vaccination guidelines and inform policy updates. We aim to propose reforms to current influenza vaccination policies based on our analysis of cost-effectiveness studies. This cross-sectional epidemiological study used influenza case, death, discharge and hospitalization data from several influenza seasons and applied a one-year decision-analytic model to assess cost-effectiveness. The primary health outcome was influenza cases avoided; secondary health outcomes were influenza-related events associated with case reduction. By increasing vaccination coverage to 75% in the population aged 12–49 years with risk factors (diabetes, high blood pressure, morbid obesity, chronic renal failure, asthma, pregnancy), and expanding universal vaccination coverage to school-aged children (5–11 years) and adults aged 50–59 years, 7142–671,461 influenza cases; 1–15 deaths; 7615–262,812 healthcare visits; 2886–154,143 emergency room admissions and 2891–97,637 hospitalizations could be prevented (ranges correspond to separate age and risk factor groups), with a net annual savings of 3.90 to 111.99 million USD. Such changes to the current vaccination policy could potentially result in significant economic and health benefits. These data could be used to inform the revision of a vaccination policy in Mexico with substantial social value

Analysis of spatial mobility in subjects from a Dengue endemic urban locality in Morelos State, Mexico.

Mathematical models and field data suggest that human mobility is an important driver for Dengue virus transmission. Nonetheless little is known on this matter due the lack of instruments for precise mobility quantification and study design difficulties.We carried out a cohort-nested, case-control study with 126 individuals (42 cases, 42 intradomestic controls and 42 population controls) with the goal of describing human mobility patterns of recently Dengue virus-infected subjects, and comparing them with those of non-infected subjects living in an urban endemic locality. Mobility was quantified using a GPS-data logger registering waypoints at 60-second intervals for a minimum of 15 natural days.Although absolute displacement was highly biased towards the intradomestic and peridomestic areas, occasional displacements exceeding a 100-Km radius from the center of the studied locality were recorded for all three study groups and individual displacements were recorded traveling across six states from central Mexico. Additionally, cases had a larger number of visits out of the municipality´s administrative limits when compared to intradomestic controls (cases: 10.4 versus intradomestic controls: 2.9, p = 0.0282). We were able to identify extradomestic places within and out of the locality that were independently visited by apparently non-related infected subjects, consistent with houses, working and leisure places.Results of this study show that human mobility in a small urban setting exceeded that considered by local health authority's administrative limits, and was different between recently infected and non-infected subjects living in the same household. These observations provide important insights about the role that human mobility may have in Dengue virus transmission and persistence across endemic geographic areas that need to be taken into account when planning preventive and control measures. Finally, these results are a valuable reference when setting the parameters for future mathematical modeling studies

Mobility of cases across dengue endemic zones in central Mexico.

<p>The figure shows the geographic distribution of visits performed by cases across central Mexico, and the cumulative incidence of dengue at municipal level for 2012.</p

Mobility description per group.

<p>Mobility description per group.</p