Dengvaxia: The Challenges and Triumphs in Dengue Vaccination
  • Post category:Blog

Dengue fever isn’t a mere statistic; it’s like a sneaky invader that affects families, friends, and neighbours.

This article delves into Degvaxia, the latest dengue vaccine. From the initial scientific breakthroughs to the complex ethical, logistical, and public health considerations, we aim to shed light on the highs and lows of this groundbreaking vaccine.

fever and headache
Photo by Andrea Piacquadio from Pexels

Dengue fever and its global impact

Dengue fever, a mosquito-borne viral infection, has emerged as a formidable global health challenge that affects millions of lives across the globe. It is spread by the mosquito Aedes aegypti, and in severe cases may cause dengue haemorrhagic fever.

WHO states that about 390 million people get dengue every year, mostly in warm regions.

Symptoms include high fever, bad headaches, joint and muscle pain, a rash, and, in severe cases, it can lead to hemorrhagic fever or shock. It’s a big deal for public health, causing around 20,000 deaths each year.

The socio-economic ramifications of dengue are equally significant. Dengue not only affects people’s health but also brings significant economic challenges. Families and individuals not only suffer physically but also face high medical costs, decreased productivity, and extra pressure on healthcare systems.

As the illness can keep people from working for a long time, it makes it harder for them to support their families creating a cycle of poverty.

What is Dengvaxia?

Multiple dengue vaccines have been under trial for the past few years. Takeda’s TAK-003 is one such vaccine intended to secure against all four types of the dengue virus.

Similarly, Dengvaxia is a dengue vaccine developed by Sanofi Pasteur, designed to provide immunity against all four dengue virus serotypes.

The development of Dengvaxia was a significant milestone in the fight against dengue, offering the potential to reduce the severity and prevalence of the disease

How does Dengvaxia work?

Dengue vaccine works by stimulating the body’s immune system to produce a defensive response against the virus. It contains weakened forms of the four dengue virus serotypes, triggering the production of antibodies in the vaccinated individual.

These antibodies act as soldiers in the immune system, ready to recognize and neutralise the virus if the person is later exposed to any of the four dengue serotypes.

Administered in three doses over several months, Dengvaxia aims to establish a lasting immune response.

This means that if a vaccinated person comes into contact with the dengue virus, their immune system is ready to defend against it. The goal is to reduce the severity of the disease, offering a level of protection that extends beyond what natural infection might provide.

dengue vaccine
https://unsplash.com/photos/DyabOTMZfNw

How long does Dengvaxia effect last?

Studies indicate that Dengvaxia’s effectiveness is not uniform across all age groups or dengue exposure statuses.

The vaccine tends to be more effective in those with a prior dengue infection. However, its protective effects can wane over time.

Research suggests that Dengvaxia may offer immunity for a certain period, but the exact duration varies. It emphasises the importance of ongoing monitoring, research, and potential booster doses to enhance and prolong the vaccine’s protective effects.

Can Dengvaxia cause severe dengue?

While Dengvaxia aims to prevent severe dengue cases, there have been concerns about the vaccine potentially causing severe dengue in individuals not previously exposed to the virus. It is vital to assess the risk-benefit ratio for different populations.

Reception and approval of Dengvaxia in various countries

Dengvaxia’s reception and approval have varied across countries.

Different nations have implemented the vaccine with specific guidelines regarding the age groups eligible for vaccination, the year of approval, and other considerations.

Is Dengvaxia FDA approved?

Dengvaxia, the first vaccine approved for the prevention of dengue disease, received approval from the U.S. Food and Drug Administration (FDA). This approval marks a significant milestone in the fight against dengue, a disease endemic in various regions across the globe.

Additionally, the Centers for Disease Control and Prevention (CDC) provides information on who is eligible for the Dengvaxia vaccine. According to the CDC, in 2019, Dengvaxia was approved for use in children and adolescents aged 9–16 years with laboratory-confirmed previous dengue infection and living in endemic areas.

Read: A comprehensive history of Dengvaxia’s FDA approval, including specific details about its use and limitations.

Who should get dengue vaccine (Dengvaxia)?

Dengvaxia is recommended for specific groups of people, including:

  • Individuals with a history of dengue infection: Dengvaxia is primarily intended for those previously infected with the dengue virus. It tends to be more effective in protecting individuals with a history of dengue.
  • People living in high-risk areas: Residents of regions where dengue is prevalent, especially in tropical and subtropical areas, are often considered for Dengvaxia vaccination. This helps reduce the risk of severe dengue infections in areas with a high disease incidence.
  • Adults and children within the approved age range: The vaccine is typically approved for use in children and adolescents aged 9–16 years with laboratory-confirmed previous dengue infection and living in endemic areas.
  • Individuals with a known prior dengue infection: Those who have experienced dengue may benefit from Dengvaxia as it adds an extra layer of protection against future diseases.

As with any vaccination, individual circumstances and medical history are vital in determining eligibility. It’s recommended to consult with healthcare professionals who can provide personalised advice based on specific conditions and regional guidelines.

dengue vaccine Malaysia
Photo by Gustavo Fring from Pexels

Who should not get dengue vaccine (Dengvaxia)?

Certain groups of people should avoid getting the Dengvaxia vaccine. These include:

  • Those who haven’t had dengue before: Dengvaxia is generally recommended for individuals previously infected with the dengue virus. For those without prior exposure, there’s a risk that the vaccine might increase the severity of subsequent infections.
  • Younger age groups: The vaccine’s effectiveness can vary across different age groups. It’s crucial to follow specific age recommendations provided by health authorities in each country.
  • Pregnant individuals: As with many vaccines, pregnant individuals are often advised to avoid them unless the potential benefits outweigh the risks. It’s crucial to consult with a certified doctor to assess individual circumstances.
  • Those with a history of severe allergic reactions: Individuals with an allergic reaction to any compound present in the vaccine should avoid getting vaccinated

Make sure that you get the opinion of a certified healthcare professional, taking into account individual medical histories and circumstances. Health authorities in each country provide guidelines regarding Dengvaxia vaccination, which should be followed for safe and effective use.

Triumphs of Dengvaxia

Dengvaxia’s development and the results from its Phase 3 trials represent a significant triumph in medical science, offering hope in regions heavily burdened by dengue.

The vaccine’s introduction into national immunization programs in dengue-endemic countries is a testament to its potential impact on public health.

It’s important to note that while Dengvaxia has been a significant step forward, its deployment and use come with specific recommendations and considerations, particularly regarding its administration based on serostatus.

The ongoing research and updates on Dengvaxia are crucial for optimizing its impact and ensuring safe and effective use in the global fight against dengue.

Some of the notable triumphs or positive aspects of Dengvaxia include:

  • Potential to reduce dengue cases: The vaccine aimed to reduce the incidence of dengue fever, which can result in severe illness and even death. Dengue is a significant health concern in many parts of the world, particularly in Asia and Latin America.
  • Comprehensive protection: Dengvaxia was designed to provide immunity against all four different variants of the dengue virus. It is a complete solution compared to previous attempts focusing on specific serotypes.
  • Public health impact: If successful, widespread vaccination with Dengvaxia could positively impact public health by lowering the burden of dengue-related hospitalizations and fatalities.

Challenges faced

  • Safety concerns: There were reports of safety concerns related to Dengvaxia, particularly in the Philippines, where the vaccine was administered to many schoolchildren. The vaccine was associated with potential risks for those not previously exposed to the virus. Read: Dengue vaccine in Pihilippines.
  • Controversial rollout: The mass vaccination campaign in the Philippines faced criticism for its implementation and the lack of proper screening for prior dengue exposure. This led to concerns about the vaccine’s safety and effectiveness.
  • Impact on trust in caccination programs: The controversy surrounding Dengvaxia had broader implications for public trust in vaccination programs. It highlighted the importance of thorough testing, transparent communication, and a careful rollout process.

Steps taken to enhance the safety and efficacy of dengvaxia

Here are some general steps that could be taken to enhance the safety and efficacy of Dengvaxia or similar vaccines:

  • Continued research and clinical trials: Efforts for clinical trials and research are essential to assess the safety and efficacy of Dengvaxia continually. Further studies can provide insights into the long-term effects, effectiveness across diverse populations, and any potential adverse reactions.
  • Post-marketing surveillance: Implementing robust post-marketing surveillance is crucial to monitor the vaccine’s safety and effectiveness once it is widely used in the general population. This involves actively collecting and analysing adverse events and vaccine efficacy data to identify emerging patterns or concerns.
  • Refining target populations: Refining and identifying specific target populations for vaccination is essential. For example, assessing the prevalence of prior dengue exposure in individuals before vaccination can help avoid potential safety issues, as Dengvaxia was associated with risks for those not previously exposed to the virus.
  • Improved screening protocols: Developing and implementing improved screening protocols to identify people at a higher risk of adverse reactions or for whom the vaccine may not be suitable is essential. This includes age, prior dengue exposure, and other relevant health conditions.
  • Enhanced communication and education: Clear and transparent communication about the vaccine’s safety and efficacy and proper education for healthcare professionals and the public is crucial. This can help manage expectations, address concerns, and ensure informed decision-making regarding vaccination.
  • Collaboration with health authorities: Working closely with health authorities and regulatory agencies is essential. These agencies play a crucial role in evaluating and overseeing the safety and efficacy of vaccines. Regular communication and cooperation can contribute to a more effective and well-monitored vaccination program.
  • Adaptive immunization strategies: Considering adaptive immunisation strategies based on evolving epidemiological data is essential. This may involve adjusting vaccination schedules or recommendations based on changes in the prevalence of different dengue virus serotypes or the overall disease burden.

Current global status of Dengvaxia usage

Dengvaxia’s use globally is a changing story. It’s approved in some countries to fight dengue, but how it is used can vary.

Countries with many dengue cases often include Dengvaxia in their vaccination plans. They decide how to use it based on how much dengue there is and which age groups need it most.

While some places have given the thumbs up to Dengvaxia, others need help with it. Considerations like the number of dengue cases, worries about how well the vaccine works, and what people think about it make the response different worldwide.

The approval changes in different countries, and they might recommend Dengvaxia for specific age groups.

Staying updated on what’s happening globally, like new approvals or changes in how the vaccine is used, helps understand Dengvaxia’s role in fighting dengue everywhere.

Future of dengue vaccination

Dengvaxia is a big step in the fight against dengue, but there’s ongoing work to improve vaccines. Scientists aim to improve existing vaccines, make them more effective, and explore new options.

Global collaboration, led by organisations like WHO, is crucial for protecting everyone at risk. Ongoing studies help us understand vaccine safety, effectiveness, and if booster doses are needed.

In addition, technology also plays a role. Better surveillance helps track and predict dengue outbreaks for targeted vaccination campaigns.

However, despite the progress, various challenges such as vaccine hesitancy and logistical issues persist. Solving these requires engaging communities, education, and building trust.

The future of dengue vaccination brings both hope and challenges. Continued research, global teamwork, and technological advances position us to tackle challenges. As we learn more about dengue prevention, the goal remains clear: a future where the impact of this mosquito-borne illness is minimised.

Bottom Line

In the intricate dance between humanity and the relentless dengue fever, Dengvaxia emerges as a vaccine and a beacon of hope. Understanding the complexities surrounding Dengvaxia’s development, distribution, and efficacy is crucial in appreciating its role in the fight against dengue.

While it has effectively reduced severe cases and hospitalizations, concerns remain regarding its long-term impact and optimal deployment strategies.

More research and evaluation are needed to optimise the use of Dengue vaccines. This includes understanding their long-term safety and efficacy, tailoring vaccination programs to specific contexts, and ensuring equitable access to these life-saving interventions.

Leave a Reply