Decrease in Hospitalizations for Pneumonia in Children under Five Years of Age in an Indian Reservation in Panama after the Introduction of the Heptavalent Pneumococcal Conjugate Vaccine (PCV7)

This study quantifies the impact of Heptavalent-Pneumococcal Conjugate Vaccine (PCV7) in Panama on indigenous children younger than 5 years old, based on clinical pneumonia cases. This study demonstrates a significant 41.2% reduction in hospitalizations and 38.6% reduction in referrals for pneumonia following the introduction of PCV7. Burden of disease from pneumonia appears reduced in the ≤12-month- and 13-to-24-month-old groups. 1. Introduction Streptococcus pneumonae is a Gram-positive, anaerobic, catalase-negative bacterium. It produces a polysaccharide capsule, that is used for serotyping; more than 90 immunologically distinct serotypes have been identified. They form 46 serogroups from which fewer than 20 serotypes account for most of cases of the disease caused by S. pneumoniae. Pneumococcal diseases have great impacts, and many of the 1.9 million deaths reported worldwide from respiratory illnesses in children younger than 5 years of age are due to S. pneumoniae [1]. In Latin America, it is estimated that 60,000 deaths a year are caused by respiratory infections, representing 3.2% of all deaths worldwide [1]. Approximately 14% of the children in that region die from acute respiratory illnesses, compared with 11% in Europe and 22% in Africa [1]. Between 12,000 and 28,000 deaths in Latin America are due to pneumococcal infections [2]. Because of the high social and economical burden of pneumococcal diseases, the World Health Organization (WHO) has recognized these infections as one of the main causes of morbidity and mortality worldwide and accepted that prevention has a key role on diminishing such burdens. Vaccination is the main preventive strategy [3], and in 2006, the WHO recommended vaccination against S. pneumonie as a priority [4]. On December 1, 2008, the Panamanian Government introduced the heptavalent pneumococcal conjugated vaccine (Prevenar, PCV7, Wyeth Pharmaceuticals Inc., a subsidiary of Pfizer Pharmaceuticals Inc, Philadelphia, PA USA) for all children ≤9 years of age in the indigenous Ng？be-Buglé Reservation. PCV 7 vaccine was administered in a four-dose schedule (2, 4, 6, and 12–15 months of age) to children less than two years old, with a single catch-up dose administered to all children between 2 and 9 years of age. The Ng？be-Buglé Region is located in the west of the Republic of Panama and comprises 6,994.06？km2, with a population of 122,423 inhabitants, including 25,178 children aged less than 5 years [5]. The poverty level in the region is 93.4%, compared to the 37.3% national average; malnutrition ranges from 35% to 63%