Determining the Effectiveness of PCV13 Vaccine in Dominican Republic

Tackling common, dangerous childhood infections in the Dominican Republic

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Global Health Update

Maria Dunn with a child In many low- and middle-income countries (LMICs), infections are the leading cause of childhood illness and death. Ear infections, meningitis, blood stream infections (“bacteremia”), and pneumonia are frequently the result of colonization of pneumococcal bacteria — of which there are over 90 strains or serotypes. Vaccination has been shown to significantly reduce cases of these diseases. The recommended vaccine against pneumococcal bacteria for children under the age of 2 is the pneumococcal conjugate vaccine-13 (PCV13), which protects against the 13 most common disease-causing strains of the pneumococcal bacteria. The vaccine is given in three doses.

See the World Health Organization data on causes of child mortality.

In 2015, Maria Dunn, DO, moved to the Dominican Republic (DR) as the fourth DR-based David N. Pincus Global Health Fellow at Children’s Hospital of Philadelphia (CHOP). Maria divided her time between Clínica de Familia in La Romana and CHOP’s program in Consuelo, known as Niños Primeros en Salud (NPS). The NPS program, established in 2009 in partnership with Centro de Salud Divina Providencia (CSDP), is a primary care and preventive health program serving children ages 0-5 years from the poorest neighborhoods in Consuelo. A few months into her time in Consuelo, Dunn noticed the high numbers of children with ear infections and pneumonia being brought for care at NPS. This experience was very different from the patients she had seen during her previous three years in private practice in the U.S.

Dr. Dunn consulted with Dr. Kristen Feemster, an attending physician in the Division of Infectious Diseases and Director of Research for CHOP’s Vaccine Education Center, and they decided to explore why these infections were so prevalent in these patients. The first objective of their study was to determine PCV13’s impact on the colonization rates of pneumococcal bacteria in the nasopharyngeal passages of children. The second objective was to determine whether the vaccine was effective against the commonly found pneumococcal bacteria in children in the DR. Previous research had been conducted in Santo Domingo which explored the common serotypes found in inpatient children in the capital city, but Dr. Dunn’s study focused on children from a rural community in an outpatient setting.

“We found that the children who received all three recommended doses of the PCV13 vaccine were significantly less likely to be colonized by vaccine-associated serotypes of pneumococcal bacteria. And, we found that the percentage of children who had received all three doses of the vaccine was lower than expected at about 60 percent” says Dr. Dunn.

One reason may be related to the cost of the vaccine: PCV13 is one of the most expensive vaccines anywhere in the world. As a result, many children will only receive one or two doses even though it is recommended to receive all three doses. Dr. Dunn’s next steps are to share detailed results with the DR’s Ministerio de Salud Pública y Asistencia Social (Ministry of Public Health and Social Assistance), and hopefully work together to improve vaccine rates for children in the DR.

“This fellowship research project taught me the importance of building relationships with people from the community who have done similar work and to build on that work rather than reinventing the wheel,” says Dr. Dunn. “I am extremely grateful to CHOP and to the Pincus Family Foundation for the opportunity to be a David N. Pincus CHOP Global Health Fellow.”

During their fellowship, fellows divide their time between clinical work and research. In Dr. Dunn’s case, she spent two days a week at Clínica de Familia in La Romana working in a pediatric HIV clinic, two days a week at NPS in Consuelo, and one day doing research. Since completing her fellowship last summer, Dr. Dunn has joined Texas Children’s Hospital Global HOPE (Hematology-Oncology Pediatric Excellence) program in Botswana. Dr. Dunn says, “My time in the DR doing community outreach with NPS nurse, Ramona Cordero, prepared me for my role now — I am working in the community raising awareness and knowledge of pediatric cancer.”

Through the continued generous support of the Pincus Family Foundation, starting in July 2019, the fellowship will evolve from a two- to a three-year program, allowing for increased research time and resources to pursue a Master in Public Health, Global Health or Epidemiology degree.

“We are thrilled by the evolution of the David N. Pincus Global Health Fellowship into the expanded three-year program, and encourage potential fellows to apply early. This is a tantalizing opportunity for pediatricians to acquire the full global health skillset in a mentored, supportive environment. Fellows will continue to be nested in one of two mature global health partnerships (Dominican Republic or Botswana), matched with expert CHOP mentors. The third year confers the additional advantages of being based longer in a global setting, acquiring a master’s degree and having an overlap year with another global health fellow — all of which will enhance each fellow’s learning experience and deepen their local impact,” says Dr. Andrew Steenhoff, Fellowship Director. “The goal of the fellowship is to train leaders in global child health. We are delighted that prior Pincus Global Health Fellow graduates are already emerging thought leaders in global child health — examples include Dr. Maria Dunn with Texas Children’s Hospital, Dr. Matt Kelly with Duke, and Dr. Kate Westmoreland with UNC. We now seek to accelerate each future fellow’s transition into their role as a leader in global child health through the enhanced three-year fellowship.”

How can I become a fellow?

CHOP’s Global Health Center works in more than 15 countries around the world. In addition to saving lives through direct clinical care, we are also dedicated to conducting locally relevant research and training the next generation of global health providers like Dr. Dunn, who in turn learn from and teach their colleagues abroad. You too can become a David N. Pincus CHOP Global Health Fellow. Email to request a global health fellowship application.

How can I help?

Since 2009, CHOP’s David N. Pincus Global Health Fellowship Program in the DR and Botswana has trained eight Pincus Global Health pediatricians, with two additional current fellows. Maria’s story is just one example of the impact of this unique fellowship — each fellow has an inspiring career story. To help us provide more global health training opportunities for the next generation of pediatricians, kindly make a gift to CHOP’s Global Health Center today.

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