NEW YORK — Despite a reduction in child mortality rates worldwide over the last two decades, critical gaps remain in vaccine program implementation and coverage, according to a keynote presentation at the 2016 Infectious Diseases in Children Symposium.
“Globally, life expectancy this century has increased by 5 years – with an increase of 10 years in Africa – mainly due to the decrease in deaths of children younger than 5 years of age,” Jon S. Abramson, MD, from the department of pediatrics at Wake Forest Medical School and the Strategic Advisory Group of Experts (SAGE) on Immunization established by WHO, said. “However, many of the deaths in this age group in low-income countries continue to be a result of vaccine-preventable diseases; 16,000 children younger than 5 years die every day, with almost 50% of these deaths now occurring in the neonatal period.”
Jon S. Abramson
To address these inconsistencies in global vaccination coverage, in 2010 the Decade of Vaccines collaboration developed the Global Vaccine Action Plan (GVAP) as an outline for achieving the goal of more equitable vaccine access for all people, regardless of location, by the end of the decade. However, as Abramson and other members of SAGE reported, as of 2015, progress toward the 2020 global vaccination targets remains far off-track.
In fact, among the six key vaccination targets that GVAP set for 2015, which called for elimination of polio, measles, rubella, maternal/neonatal tetanus as well as widespread immunization against diphtheria, tetanus, and pertussis, only the introduction of underutilized vaccines is currently on track for the 2020 goals.
While GVAP had projected a goal of 90% coverage for the three-dose diphtheria-tetanus-pertussis vaccine among infants aged 12 months, recent data highlighted that 65 countries – some with less than 50% coverage with DTP3 – will require revolutionary vaccination strategies to meet that goal.
“The number of [DTP3] unimmunized children have risen to approximately 18.7 million, with evidence that immunization progress has stagnated within the past 5 years,” Abramson said.
Additionally, while GVAP targets set for polio elimination dictated no new cases beyond 2014, polio remains endemic in Nigeria, Afghanistan and Pakistan. Abramson noted that significant progress has been made toward eliminating wild poliovirus in Afghanistan and Pakistan, as well as vaccine-derived poliovirus type 2 in Pakistan and Nigeria.
“[While] Africa had been free of wild poliovirus since August 2014, 4 cases were seen in northern Nigeria in July 2016,” Abramson noted. “Additionally, the global inactivated poliovirus vaccine supply shortage will likely persist into 2017/2018.”
GVAP goals for maternal and neonatal tetanus were similarly off-track, noted Abramson. Unlike polio and smallpox, tetanus cannot be eradicated but can be reduced to less than one case of per 1,000 births in every district. While progress continues to be made in this area, by October 2016, 18 countries have still not reached the maternal and neonatal tetanus elimination status.
“Maternal and neonatal tetanus still kills approximately 49,000 infants and a significant number of women each year,” Abramson said.
The biggest issue facing global vaccination efforts, according to Abramson, is how to implement immunization programs worldwide, including cold chain and logistics, vaccine campaigns, maintaining vaccine schedules, as well as new technologies to improve coverage rates. Additionally, while combatting well-known vaccine-preventable illnesses, global efforts are being made to investigate vaccine effectiveness against emerging diseases, such as Ebola virus, as well as development of vaccines against ESKAPE organisms that have been growing increasingly resistant to antibiotic treatments.
“At the end of the day, there are attainable goals set for a global immunized population by 2030, but that cannot be done without policy and program integration,” Abramson said. – by Kate Sherrer
Abramson, JS. “Coordinating global vaccination priorities and implementation.” Presented at: IDC NY; Nov. 19-20, 2016; New York.
Disclosure: Abramson reports no relevant financial disclosures.