Dengue: The centre of a vaccine disaster story

[Emily]

https://www.newsroom.co.nz/the-dengue-vaccine-scandal-and-the-measles-outbreak

Following vaccination, 154 children died. Most of these deaths were unrelated to the vaccine, but 19 of those who died had severe dengue fever. Exhumations have shown excessive bleeding, a hallmark of dengue haemorrhagic fever, in some of the children.

A criminal suit has been filed over the deaths of 11 of those children.

Since the scandal erupted, Filipinos' confidence in vaccines plummeted from 93 percent to less than 33 percent. Vaccination rates have dropped, and measles has spread. In 2019 alone there have been at least 477 deaths caused by measles.

http://apjai-journal.org/wp-content/uploads/2019/02/AP-100518-0309.pdf

Dengue vaccine: Global development update
Asian Pac J Allergy
Eakachai Prompetchara,1,2,3 Chutitorn Ketloy,3,4 Stephen J. Thomas,5 Kiat Ruxrungtham4,6
Abstract
The first licensed dengue vaccine, CYD-TDV (Dengvaxia?), has received regulatory approval in a number of countries. However, this vaccine has some limitations. Its efficacy against DENV2 was consistently lower than other serotypes.
Protective efficacy also depended on prior dengue sero-status of the vaccinees. Lower efficacy was observed in children with < 9 years old and dengue-na?ve individuals. More importantly, risk of hospitalization and severe dengue was increased in the youngest vaccine recipients (2-5 years) compared to controls. Thus, the quest of a better vaccine candidate continues. There are two live-attenuated vaccine candidates currently testing in phase III trial including DENVax, developed by US CDC and Inviragen (now licensed to Takeda) and TV003/TV005, constructed by US NIAID. In addition, there are several phase I–II as well as preclinical phase studies evaluating vaccines for safety and immunogenicity, this include other live-attenuated platform/strategy, purified-inactivated viruses formulated with adjuvants, DNA vaccine, subunit
vaccine, viral vector and also heterologous prime/boost strategies. The major difficulties of dengue vaccine development are included the lack of the best animal model, various immune status of individual especially in endemic areas and clear cut off of protective immunity. Several research and development efforts are ongoing to find a better effective and accessible dengue vaccine for people needed.