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© Thomson ReutersEastern equine encephalitis is a potential deadly but rare disease that causes brain damage.
The suspension of a dengue vaccine programme in the Philippines has caused trust in vaccinations to dramatically drop across the island nation, a study has found.

In 2015, over 80 per cent of people in the Philipines strongly agreed that vaccines were safe and effective. The latest polling, published in Human Vaccines & Immunotherapeutics, found that just 20 per cent of people agreed in 2018.

"We were surprised by how dramatic the drop was," said Professor Heidi Larson, director of the Vaccine Confidence Project at the London School of Tropical Medicine and Hygiene. "The whole political saga has spilled over to question vaccines and science more broadly."

The Philipines has a high incidence of dengue and, in 2016, it became one of the first countries to launch a mass vaccination of children using the drug Dengvazia, made by the French drugs giant Sanofi.

However, in November 2017, Sanofi released new data which showed that the vaccine - while protective for children who had previously been exposed to the virus - increased the long term risk of hospitalisation in those who had not.


Comment: Which suggests any protection children had came from previous exposure, not from the vaccine, because those who hadn't already been exposed were likely to suffer because of the vaccine.


By this point, the vaccine had been given to more than 800,000 schoolchildren - and 14 had died from the mosquito-borne disease, sparking a national scandal including accusations of "mass murder and plunder".

vaccines phili
Around half the world's population is at risk from dengue, a tropical disease spread by daytime mosquitoes. An estimated 284-528 million people are infected every year, and of these about 500,000 require hospitalisation and 2.5 per cent die.

The Philippines has one of the highest dengue fatality rates in the world, with 732 deaths last year.


Comment: One wonders whether this correlates with the vaccine program.


"One of the objectives of this study was to detect trust issues around vaccines early, so authorities can do something about it," said Prof Larson. "Rumour management and trust building is so important - but if you don't get in early then there can be significant long term problems."


Comment: God forbid the people talk about their experiences and the truth come out.


The study, part of the innovative Vaccine Confidence Index, included 1,500 participants and used the WIN/Gallup International representative sampling approach. The Philippines was one of 68 countries surveyed in 2015 - and was one of the countries which trusted vaccines most.

The scandal over Dengvaxia, although overblown in the press and social media in the Philippines, is not comparable to many other vaccine scares, such as the MMR scare in the UK and US which are entirely unfounded.


The World Health Organization (WHO) adjusted its recommendations on the use of Dengvaxia following the withdrawal of the vaccine in the Philippines and now says that children should be screened ahead of vaccination to check they have had previous exposure to the dengue virus. Only those with previous exposure should be vaccinated, its says.
At a glance | Dengue fever
  • Dengue is a mosquito-borne viral infection
  • The infection causes flu-like illness, and occasionally develops into a potentially lethal complication called severe dengue
  • The global incidence of dengue has grown dramatically in recent decades and about half of the world's population is now at risk
  • Dengue is found in tropical and sub-tropical climates worldwide, mostly in urban and semi-urban areas.
  • Severe dengue is a leading cause of serious illness and death among children in some Asian and Latin American countries
  • There is no specific treatment for dengue/ severe dengue, but early detection and access to proper medical care lowers fatality rates below 1%
Source: World Health Organization