Dengvaxia controversy

President Benigno S. Aquino III converses with Sanofi Pasteur chief executive officer Olivier Charmeil

President Aquino at the launching of dengue vaccine school-based immunization in Region III

Dengvaxia Controversy

The Dengvaxia controversy involves the public health concerns and political fallout surrounding the use of Dengvaxia, a vaccine developed by Sanofi Pasteur for the prevention of dengue fever. The controversy primarily took place in the Philippines, where the vaccine was administered to schoolchildren in a mass immunization program.

Background

Dengue fever is a mosquito-borne tropical disease caused by the dengue virus. Symptoms typically begin three to fourteen days after infection. This may include a high fever, headache, vomiting, muscle and joint pains, and a characteristic skin rash. In a small proportion of cases, the disease develops into severe dengue, also known as dengue hemorrhagic fever, resulting in bleeding, low levels of blood platelets, and blood plasma leakage, or into dengue shock syndrome, where dangerously low blood pressure occurs.

Dengvaxia (CYD-TDV) is a live recombinant tetravalent vaccine for dengue fever developed by Sanofi Pasteur. It is the first dengue vaccine to be licensed. The vaccine is the result of more than two decades of scientific innovation and collaboration, as well as 25 clinical studies in 15 countries around the world. However, its deployment has been controversial and has sparked public health debates.

Controversy

The controversy began in late 2017 when Sanofi Pasteur released a statement indicating that Dengvaxia could increase the risk of severe dengue in those who had never been infected by the virus before receiving the vaccine. This announcement caused panic among the public and was a significant concern for parents of vaccinated children.

The Philippines' Department of Health (DOH) had launched a school-based vaccination program in 2016, targeting over 800,000 children. Following Sanofi's announcement, the program was suspended, and investigations were initiated to assess the implications of the vaccination campaign.

Critics of the vaccination program pointed to the haste with which it was rolled out, alleging insufficient testing and lack of transparency regarding the vaccine's potential risks. The controversy has led to a decline in vaccine confidence in the country, affecting the uptake of other vaccines and contributing to outbreaks of diseases such as measles.

Investigations and Legal Actions

The Philippine government conducted several investigations into the Dengvaxia program. The Senate of the Philippines held hearings, and the Department of Justice (DOJ) initiated a probe into the officials involved in the vaccine's procurement and administration.

Legal actions were taken against former health officials and executives from Sanofi Pasteur. Accusations included criminal negligence and failure to adequately inform the public about the vaccine's risks.

Impact

The Dengvaxia controversy has had a significant impact on public health in the Philippines and beyond. Vaccine confidence has plummeted, leading to lower vaccination rates for diseases preventable by vaccines. The incident has underscored the importance of transparency and rigorous safety testing in public health initiatives.

Conclusion

The Dengvaxia controversy highlights the challenges of implementing large-scale vaccination programs, especially in regions burdened by endemic diseases. It underscores the need for clear communication, thorough testing, and robust regulatory frameworks to ensure the safety and efficacy of vaccines.