If this is not your name, click here.
| | If this is not your name, click here. | | |
| | Contact Us | Order Now | Journals | Bookstore | Register a colleague | | |
| |  PCV7 Vaccine Provides Significant Decline in Overall Incidence of Invasive Pneumococcal Disease in Infants: Presented at ECCMID By Chris Berrie HELSINKI, Finland -- May 26, 2009 -- Introduction of the heptavalent pneumococcal conjugate vaccine (PCV7) provided a significant decline in overall incidence of invasive pneumococcal disease (IPD) in children aged younger than 2 years, according to a prospective, cohort study presented here at the 19th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID). "We introduced the heptavalent pneumococcal conjugate vaccine in Denmark to the childhood immunisation programme in October 2007, for all children at the ages of 3, 5, and 12 months," said Zitta B. Harboe, MD, Department of Bacteriology, Mycology and Parasitology, Division of Microbiology and Diagnostics, Statens Serum Institute, Copenhagen, Denmark, on May 17. A catch-up programme (2 doses) was also offered to children between 12 and 17 months. The aim was to evaluate the effectiveness of this PCV7 vaccination programme on IPD from 1 year after its introduction. To achieve this, nationwide surveillance data on IPD, and PCV7-coverage data from the Danish Childhood Vaccination Registry were combined. A pre-PCV7 period (2000-2007) was defined for analysis, with the post-PCV7 year of 2008 as the active treatment period. "So we were able to follow-up all cases of invasive pneumococcal disease after the introduction of the vaccine," said Dr. Harboe. In 2008, the total of 938 cases of IPD represented 89% of the annual mean from the pre-PCV7 period (n = 1,055); 90% of these were bacteraemia. As the number of cases per 100,000 at risk, this provided a significant decline from the pre-PCV7 mean of 19.6, to 17.1 (P < .001). According to age groups, in children aged younger than 2 years, the mean incidence decreased significantly, from 54.8 to 23.8 cases/100,000 (P < .05). In contrast, there was a small, but significant, increase for group aged 2 to 5 years (8.5 vs 11.8; P < .05). Across all the other age groups, age 5 years to adults aged 65 years and older, continued decreasing trends were seen (5-18 years, 2.6-1.5; 18-50 years, 7.1-5.8; 50-64 years, 23.5-19.5; >=65 years, 65.9-61.2). According to serotypes, in the pre-PCV7 period, the most prevalent serotypes in children aged younger than 2 years were: 14 (21%), 6B (20%), 7F (9%), 6A (8%), 19F (7%), and 23F (7%). For the post-PCV7 year, the 7F serotype was the most prominent in these children (32%). The mean incidence of IPD caused by the PCV7 vaccine serotype (VT-IPD) in children aged younger than 2 years significantly decreased from 36.7 to 7.7 cases/100,000 (P < .001). A smaller, but significant, decrease was seen for VT-IPD in the remaining patient population (>= 2 years): from 7.0 to 5.2 cases/100,000 (P < .001), with no change in non-VT-IPD patients. Thus Dr. Harboe noted, "This is a very good example of what the vaccine effect can be in a population that you start to vaccinate, quickly and completely at the same time." Furthermore, she added, "I believe that we will see that this [incidence in children <2 years] will continue going down, and what will be interesting to look at in the future is if we have other serotypes coming up instead of those that are included in the vaccine." [Presentation title: Effectiveness of Heptavalent Pneumococcal Conjugate Vaccination on Invasive Pneumococcal Disease One Year After the Introduction in the Danish Childhood Vaccination Programme. Abstract P1130]
|
