[Emergence of invasive pneumococcal disease caused by non-vaccine serotypes in the era of the 7-valent conjugate vaccine]

Invasive pneumococcal disease in children under 60 months before and after availability of 13-valent conjugate vaccine

BACKGROUND

Invasive pneumococcal disease (IPD) is the most important bacterial infection in young children, and the introduction of pneumococcal conjugate vaccines has changed its presentation. This study compared the incidence, characteristics and serotype distribution of IPD before and after the introduction of the pneumococcal conjugate vaccine (PCV13).

METHODS

Prospective enrolment of patients with IPD aged less than 60 months and admitted to either of 2 tertiary care hospitals between January 2007 and December 2009 (pre-PCV13 period) and January 2012 and June-2016 (PCV13 period).

RESULTS

We identified 493 cases, 319 in the pre-PCV13 period and 174 in the PCV13 period. The incidence of IPD decreased from 89.7 to 34.4 casos per 100 000 habitantes ( -62%; P < .001). This decrease was observed in all forms of disease except necrotising pneumonia (increase from 0.8 to 3.7 casos/100 000 population). There was a significant reduction in all serotypes included in the PCV13 and not included in the PCV7. We did not find significant differences in length of stay, mortality or the frequency of sequelae between both periods, but in the PCV13 period, the length of stay in the paediatric intensive care unit and the duration of mechanical ventilation were longer (P = .00). The incidence of serotype 3 decreased from 10.4 to 6.9 casos per 100 000 population, although it was the serotype involved most frequently in patients with severe disease.

CONCLUSIONS

After the introduction of the PCV13, there has been a significant decrease in IPD cases. Serotype 3 continues to be an important cause of severe IPD.

[Invasive pneumococcal disease in children under 60 months before and after availability of 13-valent conjugate vaccine]

BACKGROUND

Invasive pneumococcal disease (IPD) is the most important bacterial infection in young children, and the introduction of pneumococcal conjugate vaccines has changed its presentation. This study compared the incidence, characteristics and serotype distribution of IPD before and after the introduction of the pneumococcal conjugate vaccine (PCV13).

METHODS

Prospective enrolment of patients with IPD aged less than 60 months and admitted to either of 2 tertiary care hospitals between January 2007 and December 2009 (pre-PCV13 period) and January 2012 and June-2016 (PCV13 period).

RESULTS

We identified 493 cases, 319 in the pre-PCV13 period and 174 in the PCV13 period. The incidence of IPD decreased from 89.7 to 34.4 cases per 100,000 population (-62%; P<.001). This decrease was observed in all forms of disease except necrotising pneumonia (increase from 0.8 to 3.7 cases/100,000 population). There was a significant reduction in all serotypes included in the PCV13 and not included in the PCV7. We did not find significant differences in length of stay, mortality or the frequency of sequelae between both periods, but in the PCV13 period, the length of stay in the paediatric intensive care unit and the duration of mechanical ventilation were longer (P=.00). The incidence of serotype 3 decreased from 10.4 to 6.9 cases per 100,000 population, although it was the serotype involved most frequently in patients with severe disease.

CONCLUSIONS

After the introduction of the PCV13, there has been a significant decrease in IPD cases. Serotype 3 continues to be an important cause of severe IPD.

Do Pneumococcal Conjugate Vaccines Represent Good Value for Money in a Lower-Middle Income Country? A Cost-Utility Analysis in the Philippines

Objectives

The objective of this study is to assess the value for money of introducing pneumococcal conjugate vaccines as part of the immunization program in a lower-middle income country, the Philippines, which is not eligible for GAVI support and lower vaccine prices. It also includes the newest clinical evidence evaluating the efficacy of PCV10, which is lacking in other previous studies.

Methods

A cost-utility analysis was conducted. A Markov simulation model was constructed to examine the costs and consequences of PCV10 and PCV13 against the current scenario of no PCV vaccination for a lifetime horizon. A health system perspective was employed to explore different funding schemes, which include universal or partial vaccination coverage subsidized by the government. Results were presented as incremental cost-effectiveness ratios (ICERs) in Philippine peso (Php) per QALY gained (1 USD = 44.20 Php). Probabilistic sensitivity analysis was performed to determine the impact of parameter uncertainty.

Results

With universal vaccination at a cost per dose of Php 624 for PCV10 and Php 700 for PCV13, both PCVs are cost-effective compared to no vaccination given the ceiling threshold of Php 120,000 per QALY gained, yielding ICERs of Php 68,182 and Php 54,510 for PCV10 and PCV13, respectively. Partial vaccination of 25% of the birth cohort resulted in significantly higher ICER values (Php 112,640 for PCV10 and Php 84,654 for PCV13) due to loss of herd protection. The budget impact analysis reveals that universal vaccination would cost Php 3.87 billion to 4.34 billion per annual, or 1.6 to 1.8 times the budget of the current national vaccination program.

Conclusion

The inclusion of PCV in the national immunization program is recommended. PCV13 achieved better value for money compared to PCV10. However, the affordability and sustainability of PCV implementation over the long-term should be considered by decision makers.

Pneumococcal meningitis: epidemiological profile pre- and post-introduction of the pneumococcal 10-valent conjugate vaccine

OBJECTIVES

To evaluate the possible effects of the introduction of the pneumococcal conjugate 10-valent vaccine schedule in the state of Parana on pneumococcal meningitis cases and to assess the distribution of serotypes among cases.

METHOD

Cross-sectional study with retrospective data collection of cases of pneumococcal meningitis in the state of Paraná reported to Sistema de Informação de Agravos de Notificação (SINAN), from 1998 to 2011. A total of 1,339 cases of pneumococcal meningitis were analyzed; 1,205 cases from the pre-vaccine period (1998-2009) were compared to 134 cases from the post-vaccine period (2010-2011). Descriptive and comparative statistical analyses (chi-squared test and prevalence ratio) were performed using JMP 5.1.2 statistical software (JMP Statistical Discovery, North Carolina, USA) and EPI INFO 6 (Centers for Disease Control and Prevention, Georgia, EUA).

RESULTS

There was a significant reduction in the mean rates of incidence and mortality in the general population. The analysis of cases in the pre- and post-vaccination periods in the age groups covered by vaccination (younger than 2 years) showed significant reductions in incidence rates (6.01 cases/100,000 to 2.49 cases/100,000 individuals) and mortality (1.85 cases/100,000 population to 0.47 cases/100,000 population), while the mean lethality rate did not change significantly. There was a significant reduction in cases whose serotypes are included in the vaccine (80.7% to 53.3%).

CONCLUSION

Even after a short time of use, the 10-valent pneumococcal conjugate vaccine has already had a significant impact in reducing the incidence and mortality of meningitis cases among infants, as well as the reduction of cases whose serotypes are included in the vaccine.