Continuous Pneumococcal Invasive Disease Reduction, High Impact on Pneumococcal Empyemas and Meningitis, and Serotype 19A Disappearance Following PCV-13 Vaccination in Children: Eleven and a Half Years of Active Surveillance in a Mexican Hospital on the U.S. Border

Abstract

BackgroundThe Tijuana, Mexico and San Diego, California, is the world’s most transited frontier. We have previously published pneumococcal serotype replacement following PCV-7 introduction, especially by serotypes 19-A, 3 and 6A/C. Since May/2012 universal vaccination with PCV-13 was introduced for all children. This study analyzes the effectiveness of PCV-13 after its implementation in the region.MethodsSince October/2005 until March/2017 (11.5 years) we underwent an active surveillance for all Invasive Pneumococcal Diseases (IPD) in children < 16 years admitted at the Tijuana General Hospital. Only culture-confirmed cases were included. Following identification, serotyping was performed using the Quellung Reaction (Statens Serum Institute® Copenhagen, Denmark). Descriptive analysis was performed using Excel®.ResultsFifty-seven cases of confirmed IPD were found. Clinical diagnosis were pleural empyemas (PPE) (45.6%), meningitis (PM) (28%), otomastoiditis (15.7%), only sepsis (7%), and bacteremic pneumonia (3.5%). Median age was of 3.9 years (2 days – 15.9 years), median hospitalization days was of 14 (1–90). Overall mortality was of 6 (10.5%). Following PCV13 introduction there was a decreased on overall IPD mortality by 73.29%, overall IPD by 68%, PPE by 68.1%, and PM by 55.4%. However, during 2015–16, we had three PM cases, two of which were immunocompromised patients, and none vaccinated with PCV13. From an average of 1.75 yearly cases due to pneumococcal serotype 19-A before PCV13 implementation, there had been no patients with IPD’s caused by this serotype. (See Figure 1). After PCV13 vaccination, serotypes associated with IPD cases had been as follow: Two 22F, and one each by 6A, 18C, 3, 7F, 15, 7B, 35B, 24F and 33F.ConclusionThis is the first Mexican study based on active surveillance that shows consistent effectiveness of PCV-13 on reduction of overall IPD, disappearance of pneumococcal serotype 19-A, and strong impact on PPE in children. Effectiveness on PM is still above 50%, however, during 2015–16 there had been three cases, but with particular conditions (immunodeficiencies and no vaccination). Continuous active surveillance is mandatory.Disclosures All authors: No reported disclosures.