Data analyzed in Joinpoint regression.

Background
Neonatal sepsis remains a leading cause of morbidity and mortality in neonates across all regions, including Africa. Compared to developed and some developing countries, there are relatively few epidemiological trends for neonatal sepsis and associated patterns with COVID-19 in Ethiopia. We modeled an epidemiological trend and pattern to aid in the monitoring of changes in neonatal sepsis.
Methods
Retrospective data were collected from all admissions to the Neonatal Intensive Care Unit (NICU) in Ethiopia at Jimma Medical Center between May 2019 and April 2022. We analyzed the monthly neonatal sepsis incidence, mortality, and case-fatality rates using STATA software. Finally, we modeled a monthly time series of neonatal sepsis incidence trends and patterns associated with the COVID-19-impacted period using Joinpoint software. For all analyses, a P value of 0.05 was considered statistically significant at the 95% confidence interval (CI).
Results
In the 36 months, 6796 cases were admitted to the NICU, with a 9.5% (95% CI: 9.1, 10.0) incidence rate of neonatal sepsis. The overall admission mortality rate was 16.5% (95% CI: 13.6, 19.8), while sepsis-attributed mortality was 7.1% (95% CI: 5.8, 8.5). The data showed an unstable decreasing trend for three Joinpoints (August 2020, December 2020, and August 2021). Notably, a decrease in the incidence trend was observed from May 2019 to August 2020 (MPC, -4.1; 95% CI: -7.6, -0.5; P = 0.03), followed by a sharp increase (MPC, 23.7; 95% CI: -13.8, 77.7; P = 0.24) from August 2020 to December 2020. From December 2020 to August 2021, there was again a decreasing trend (MPC, -13.8; 95% CI: -23.3, -3.5; P = 0.01), followed by a slight increase from August 2021 to April 2022 (MPC, 4.2; 95% CI: -8.4, 18.6; P = 0.52). Finally, the study revealed an association between patterns of neonatal sepsis incidence trends and COVID-19, with a Joinpoint jump model comparability ratio (CR = 0.43) between pre- and COVID-19-impacted periods.
Conclusions
Neonatal sepsis was prevalent at Jimma Medical Center, but it was on an unstably declining trend. The current results suggest a potential temporal association between the intensity of COVID-19 containment measures and a change in the incidence trend and patterns of neonatal sepsis. However, the quantified contribution of a particular containment measure requires further investigation.

背景
新生儿脓毒症（neonatal sepsis）仍是全球各地区新生儿发病与死亡的首要诱因之一，非洲地区亦不例外。相较于发达国家与部分发展中国家，埃塞俄比亚针对新生儿脓毒症的流行病学趋势，以及其与新型冠状病毒肺炎（COVID-19）相关的流行模式的研究相对匮乏。本研究通过构建流行病学趋势与流行模式模型，助力新生儿脓毒症的动态变化监测。

方法
本研究回顾性收集了2019年5月至2022年4月期间，埃塞俄比亚季马医疗中心（Jimma Medical Center）新生儿重症监护病房（Neonatal Intensive Care Unit, NICU）的全部入院病例数据。采用STATA软件分析新生儿脓毒症的月度发病率、死亡率与病死率。最后，使用Joinpoint软件构建新生儿脓毒症发病率趋势的月度时间序列模型，并分析其与受COVID-19影响时期的关联模式。本研究所有分析均以P值0.05作为95%置信区间（confidence interval, CI）下的统计学显著性阈值。

结果
在为期36个月的研究周期内，共计6796例患儿收入NICU，新生儿脓毒症发病率为9.5%（95%CI：9.1, 10.0）。总体入院死亡率为16.5%（95%CI：13.6, 19.8），而脓毒症相关死亡率为7.1%（95%CI：5.8, 8.5）。数据分析显示，存在3个具有统计学意义的连接点（Joinpoint），分别为2020年8月、2020年12月与2021年8月，整体趋势呈不稳定下降态势。具体而言，2019年5月至2020年8月期间，发病率呈下降趋势（月度百分比变化MPC，-4.1；95%CI：-7.6, -0.5；P=0.03）；随后2020年8月至2020年12月，发病率出现急剧上升（MPC，23.7；95%CI：-13.8, 77.7；P=0.24）。2020年12月至2021年8月，发病率再次呈现下降趋势（MPC，-13.8；95%CI：-23.3, -3.5；P=0.01）；2021年8月至2022年4月则出现小幅上升（MPC，4.2；95%CI：-8.4, 18.6；P=0.52）。最终，本研究揭示新生儿脓毒症发病率趋势模式与COVID-19存在关联：新冠疫情前与受COVID-19影响时期的连接点跳跃模型可比性比值（comparability ratio, CR）为0.43。

结论
季马医疗中心的新生儿脓毒症流行率较高，但整体呈不稳定下降趋势。本研究结果提示，COVID-19防控措施的实施强度与新生儿脓毒症发病率趋势及流行模式的变化存在潜在的时间关联性。不过，特定防控措施的量化贡献仍需进一步研究探明。