Send to a friend
Philippine disease outbreaks linked to vaccine fear
[MANILA] “Some mothers call health workers on immunisation drives child killers,” says Lulu Bravo, professor emeritus at the College of Medicine, University of the Philippines, describing a trend towards vaccine hesitancy that has resulted in the deaths of hundreds of children.
Vaccine hesitancy worsened after November 2017 when authorities withdrew Dengvaxia, a dengue vaccine, for risks associated with it. Since then the Philippines has seen an outbreak of measles which resulted to 42,000 cases this year, almost three times for the same period last year, and over 500 deaths, up from 128. There was also an outbreak of polio in September, nearly two decades after the World Health Organization (WHO) declared the country polio-free. Additionally, the health department reported that cases of diphtheria, the vaccine for which is included in the 6-in-1 vaccine given to infants, jumped 167 cases and 40 deaths from January to September this year from 122 cases and 30 deaths in the same period in 2018.
“Dengvaxia has been branded a killer vaccine when, in fact, the opposite is true”
Lulu Bravo, University of the Philippines
“Dengvaxia has been branded a killer vaccine when, in fact, the opposite is true,” says Bravo, who heads the Vaccine Study Group at the UP’s National Institutes of Health. “Without the vaccine’s protection, children are at risk of getting dengue, a potentially fatal disease”. Bravo claims the Philippines has the highest number of dengue cases in the world this year (at 336,000 for the period 1 January to 28 September, up from 157,000 for the same period last year).
“Vaccine hesitancy contributed to the already worsening problem of low vaccine coverage,” health secretary Francisco Duque tells SciDev.Net. “The 2018–2019 measles outbreak was an eye-opener and we paid a very high price — the lives of more than 500 children.”
Duque says that outbreaks of vaccine-preventable diseases such as measles and polio have been returning to the Philippines and are “undeniable proof” that vaccine hesitancy has negatively impacted the country’s immunisation programme.
“Amidst the controversies, the hysteria and the chaos, come the outbreaks” he says. “Vaccine hesitancy, if not properly addressed by appropriate risk communication strategies, will result [in] long-term lowering of vaccine coverage among the population, which will result in low population immunity and outbreaks of vaccine-preventable diseases.”
In 2016, the Philippines was the first country in Asia to approve the use of Dengvaxia in mass immunisations. The vaccine is made by Sanofi Pasteur, the vaccines division of the French pharmaceutical company Sanofi.
Over 800,000 children had received the vaccine before its distribution was stopped as Sanofi Pasteur reported in 2017 that children who received the vaccine, but did not have any previous dengue infection, could be at risk of acquiring a more severe dengue infection.
Data Source: Department of Health
As the controversy dragged on, the Department of Health declared a polio outbreak on 19 September this year, 19 years after the country became polio-free. The outbreak was partly traced to parents reluctant to have their children immunised because of safety fears.
“The problem is that our people have lost their vaccine confidence,” Bravo said. The decline in Philippine vaccination rates is seen in the latest report issued in July by WHO and UNICEF.
The report covered immunisation with either oral or inactivated polio vaccine as well as the vaccines Bacillus Calmette Guerin (BCG); diphtheria and tetanus toxoid with pertussis (DTP); measles; rubella; hepatitis B; Haemophilus inﬂuenzae type b; rotavirus; and pneumococcal conjugate.
The report says the decline in the coverage of the oral polio vaccine and inactivated polio vaccine during 2017 and 2018 “may reﬂect public perceptions of doubt related to vaccination following the dengue vaccine issue as well as challenges with service delivery, including access issues in hard-to-reach areas”.
“In the Philippines, we know that vaccine confidence has decreased,” Rabindra Abeyasinghe, WHO country representative to the Philippines, tells SciDev.Net. “The DOH is faced with a huge challenge in responding to the polio outbreak.”
He points to a study by the London School of Hygiene and Tropical Medicine documenting those who believe “that vaccines are important, are safe and are effective”. The number of vaccine supporters dropped from close to 100 per cent in 2015 to 60–80 per cent in 2018. “This reveals a critical need to combat misinformation and improve public understanding of the importance and safety of vaccines,” he says.
In another study published October 2018 in Human Vaccines & Immunotherapeutics measured the impact of the Dengvaxia scare and compared vaccine confidence levels in 2015 with confidence levels in 2018.
The findings reflect a drop in vaccine confidence from 93 per cent strongly agreeing that vaccines are important in 2015 to 32 per cent in 2018. Those strongly agreeing that vaccines are safe dropped in number from 82 per cent to 21 per cent in the same period; confidence in the effectiveness of vaccines dropped from 82 per cent to 22 per cent in the same period.
The study noted that when risks associated with Dengvaxia were announced, some countries adjusted their distribution guidelines. In contrast, the Philippines “reacted with outrage and political turmoil with naming and shaming of government officials involved in purchasing the vaccine, as well as scientists involved in the vaccine trials and assessment”. The result was broken public trust around vaccines in general, the study said.
Duque says, one way forward is to educate parents and the community and to address specific concerns directly. “For example, if parents are concerned about safety, it is helpful to show that vaccine testing and licensure is thorough. Pain is another common reason for vaccine hesitancy, and there are several options for pain reduction.”
Health services may not be first in the order of priorities as village health centres often lack vaccines or health personnel, Domingo says. “People also forget to have children vaccinated, or parents go to work and there’s nobody to bring children to health centres. There is less motivation.”
This piece was produced by SciDev.Net’s Asia & Pacific desk.