Masresha Balcha Girma, Luce Richard, Weldegebriel Goitom, Katsande Reggis, Gasasira Alex, Mihigo Richard
WHO, Regional Office for Africa, Brazzaville, Congo.
WHO, Inter-country team for Western Africa, Ouagadougou, Burkina Faso.
Pan Afr Med J. 2020 Jan 6;35(Suppl 1):8. doi: 10.11604/pamj.supp.2020.35.1.19059. eCollection 2020.
Guinea, Sierra Leone and Liberia have attained significant reduction in measles incidence between 2004 and 2013. The Ebola outbreak in 2014-2015 in West Africa caused significant disruption of the health service delivery in the three worst affected countries. The magnitude of the impact on the immunization program has not been well documented.
We reviewed national routine immunization administrative coverage data as well as measles surveillance performance and measles epidemiology in the years before, during and after the EVD outbreak in Guinea, Liberia, Sierra Leone.
Both Liberia and Guinea experienced a sharp decline of more than 25% in the monthly number of children vaccinated against measles in 2014 and 2015 as compared to the previous years, while there was no reported decline in Sierra Leone. Guinea and Liberia experienced a decline in measles surveillance activity and performance indicators in 2014 and 2015. During this period, there was an increase in measles incidence and a decline in the mean age of measles cases reported in Liberia and Sierra Leone. Guinea started reporting high measles incidence in 2016. All three countries organized measles supplemental immunization activities by June 2015. Liberia achieved 99% administrative coverage, while Guinea and Sierra Leone attained 90.6% and 97.2% coverage respectively. There were no severe adverse events reported during these mass vaccination activities. The disruptive effect of the Ebola outbreak on immunization services was especially evident in Guinea and Liberia. Our review of the reported administrative vaccination coverage at national level does not show significant decline in measles first dose vaccination coverage in Sierra Leone as compared to other reports. This may be due to inaccuracies in coverage monitoring and data quality problems. The increases in measles transmission and incidence in these three countries can be explained by the rapid accumulation of susceptible children. Despite the organization of mass vaccination activities, measles incidence through 2017 has remained higher than the pre-Ebola period in all three countries.
The Ebola outbreak in West Africa significantly affected measles vaccination coverage rates in two of the three worst affected countries, and led to persistent gaps in coverage, along with high measles incidence that was documented until two years after the end of the Ebola outbreak. Liberia and Sierra Leone have demonstrated coverage improvements after the end of the Ebola outbreak.
几内亚、塞拉利昂和利比里亚在2004年至2013年期间麻疹发病率显著降低。2014 - 2015年西非爆发的埃博拉疫情严重扰乱了三个疫情最严重国家的卫生服务提供。对免疫规划的影响程度尚未得到充分记录。
我们回顾了几内亚、利比里亚、塞拉利昂在埃博拉病毒病疫情爆发前、期间和之后的国家常规免疫行政覆盖率数据以及麻疹监测表现和麻疹流行病学情况。
与前几年相比，利比里亚和几内亚在2014年和2015年每月接种麻疹疫苗的儿童数量急剧下降超过25%，而塞拉利昂没有报告下降情况。几内亚和利比里亚在2014年和2015年麻疹监测活动和绩效指标有所下降。在此期间，利比里亚和塞拉利昂麻疹发病率上升，报告的麻疹病例平均年龄下降。几内亚在2016年开始报告高麻疹发病率。到2015年6月，所有三个国家都组织了麻疹补充免疫活动。利比里亚实现了99%的行政覆盖率，而几内亚和塞拉利昂分别达到了90.6%和97.2%的覆盖率。在这些大规模疫苗接种活动期间没有报告严重不良事件。埃博拉疫情对免疫服务的破坏作用在几内亚和利比里亚尤为明显。我们对国家层面报告的行政疫苗接种覆盖率的审查显示，与其他报告相比，塞拉利昂麻疹首剂疫苗接种覆盖率没有显著下降。这可能是由于覆盖率监测不准确和数据质量问题。这三个国家麻疹传播和发病率的增加可以用易感儿童的迅速积累来解释。尽管组织了大规模疫苗接种活动，但直到2017年，这三个国家的麻疹发病率仍高于埃博拉疫情前的水平。
西非的埃博拉疫情严重影响了三个疫情最严重国家中两个国家的麻疹疫苗接种覆盖率，并导致覆盖率持续存在差距，同时麻疹发病率居高不下，这种情况在埃博拉疫情结束后两年仍有记录。埃博拉疫情结束后，利比里亚和塞拉利昂的覆盖率有所提高。
