2003-05-23-世界卫生组织-Meningitis_Week_19,_1_January_2003_to_11_May_2003_6页_124kb

Regional Meningitis Surveillance Summary

Core Content

This document provides an overview of the suspected meningitis situation in several countries within the African Meningitis Belt during the first 19 weeks of 2003. It includes case numbers, fatality rates, pathogen identification, and vaccination activities. The data is reported to the World Health Organization (WHO) and highlights the trends and regional distribution of the disease.

Main Countries and Their Situation

• Benin:

  • Total cases: 350
  • Total deaths: 76
  • Case Fatality Ratio (CFR): 21.7%
  • Pathogens identified: 2 Nm W135 and 6 Nm Ad
  • Observations: Vaccination was conducted in two districts (Tangieta, Toucountouna)

• Burkina Faso:

  • Total cases: 7,417
  • Total deaths: 1,104
  • CFR: 14.9%
  • Pathogens identified: 264 Nm A and 104 Nm W135
  • Observations: Laboratory results were available until week 18

• Chad:

  • Total cases: 468
  • Total deaths: 72
  • CFR: 15.4%
  • Pathogens identified: N/A
  • Observations: No cases were reported in week 16

• Ghana:

  • Total cases: 1,399
  • Total deaths: 177
  • CFR: 12.6%
  • Pathogens identified: 8 Nm A in Bole, 11 Nm A in Maprusi, 7 Nm A in WA, and no Nm W135 in epidemic areas
  • Observations: No additional comments

• Mali:

  • Total cases: 723
  • Total deaths: 49
  • CFR: 6.8%
  • Pathogens identified: 16 Nm A and 11 Nm W135
  • Observations: No circle in alert; laboratory results until week 13 to be cross-checked

• Niger:

  • Total cases: 7,029
  • Total deaths: 566
  • CFR: 8.05%
  • Pathogens identified: 346 Nm A and 42 Nm W135
  • Observations: 3 districts still in alert (Matameye, Magaria, Aguie)

• Nigeria:

  • Total cases: 3,348
  • Total deaths: 257
  • CFR: 7.7%
  • Pathogens identified: 3 Nm A and 2 Nm W135
  • Observations: Significant underreporting; ongoing CSM activity in Yobbe State, but no data available. Vaccinations were conducted on a low scale around affected areas

• Togo:

  • Total cases: 298
  • Total deaths: 61
  • CFR: 21.1%
  • Pathogens identified: 35 Neisseria meningitidis and 1 Haemophilus influenzae
  • Observations: No reagents available for serogrouping

Key Information

• Decreasing Trend: A decreasing trend in the number of suspected meningitis cases is observed in all reporting countries.
• Pathogen Distribution:
  • Nm A is the most commonly identified pathogen.
  • Nm W135 is also present but less frequently.
  • In Niger, Nm A accounts for the majority of isolates (346), with Nm W135 identified in 42 cases.
• Vaccination Activities:
  • Vaccinations were conducted in some regions, particularly in Benin and Niger.
  • However, in Nigeria, vaccination efforts were limited and only in certain affected areas.
• Underreporting:
  • Nigeria shows significant underreporting, which may affect the accuracy of the data.
• Case Fatality Ratio (CFR):
  • The CFR varies across countries, with Togo having the highest at 21.1% and Mali the lowest at 6.8%.
• Data Availability:
  • Some countries, like Nigeria and Togo, have partial or no data for certain weeks or regions, which may impact the analysis.

Summary of Regional Trends

• The epidemic is primarily concentrated in the African Meningitis Belt, with the highest number of cases reported in Burkina Faso (7,417) and Nigeria (3,348).
• The case fatality ratio is relatively high in Benin (21.7%) and Togo (21.1%), but lower in other regions like Mali (6.8%) and Niger (8.05%).
• Nm A is the dominant serogroup across most countries, while Nm W135 is also identified in several regions.
• Vaccination efforts have been implemented in some areas, but not on a large scale in all affected regions, particularly in Nigeria.
• Underreporting and incomplete data are noted in some areas, which may lead to an underestimation of the true disease burden.

Conclusion

The document underscores the ongoing meningitis surveillance in the African Meningitis Belt, highlighting the need for improved data collection and reporting, especially in regions with limited resources. The decreasing trend in cases is encouraging, but the high CFR in some countries suggests the importance of continued public health interventions and vaccination programs.