2023-07-16-世界卫生组织-Immunization_Congo_the_2023_country_profile_21页_417kb

Congo Immunization Coverage Trends (2011-2023)

WHO and UNICEF provide annual estimates of national immunization coverage for various vaccines (BCG, DTP1/3, Polio, MCV, RCV, Hepatitis B, Hib, Pneumococcal, Rotavirus, Yellow Fever) based on reported data, administrative records, and surveys (when available). Estimates are country-specific and publicly available, with updates planned for July 15, 2024.

Key Findings:

• Coverage Levels: Most vaccines (e.g., BCG, DTP, Pol3, MCV1) had coverage around 70-90% during this period. However, there was variation across years and vaccines.
• Data Quality and Confidence (GoC): Estimates are supported by reported data ([R+]), survey data ([S+]), and demographic adjustment ([D+]). A confidence grade reflects empirical support but does not assess data quality; thus, estimates should be used with caution. For instance:
  • High confidence (•••) was given to several vaccines in 2013-2014 based on reported data and surveys (e.g., BCG: 95%, DTP1: 90%, MCV1: 83% in 2013).
• Challenges and Declines: Some years saw significant declines, often linked to stockouts or increases in target population size (e.g., 2016). Temporary stockouts were reported in 2015 (DTP/IPV), 2016 (MCV2, Rotavirus), and 2018-2021 (multiple vaccines).
• Survey Reliance: National representative surveys are crucial; their absence often challenges the confidence grade or requires adjustments. The 2014-2015 DHS survey influenced official estimates for several antigens (e.g., HepB3: 57%, DTP3: 68%).
• Antigens of Focus: Polio (Pol3/IPV), Measles (MCV1/2), and HepB coverage fluctuated, with continuous efforts to integrate vaccines like Hib, Pneumococcal, and Rotavirus.

Survey Methodology:

• Surveys primarily used household data from children aged 12-23 months to estimate infant coverage.
• Real-time data, historical records, and card-based verification adjusted for recall bias (e.g., RCV1: 53% in 2013).
• Sources included recurring surveys like the DHS (Demographic and Health Survey), MVAC (Multi-Country Vaccination Coverage) cards, and routine vaccination coverage surveys.

**In summary, Congo's immunization coverage is dynamic, influenced by stock availability, data quality, and external factors, with WHO/UNICEF providing annually updated estimates for programmable actions.