Pokharel Anjana, Adhikari Khagendra, Gautam Ramesh, Uprety Kedar Nath, Vaidya Naveen K
Padma Kanya Multiple Campus, Tribhuvan University, Kathmandu, Nepal.
Mathematical Biology Research Center, Kathmandu, Nepal.
Infect Dis Model. 2024 May 4;9(4):1007-1026. doi: 10.1016/j.idm.2024.04.012. eCollection 2024 Dec.
Despite the availability of successful vaccines, measles outbreaks have occurred frequently in recent years, presumably due to the lack of proper vaccination implementation. Moreover, measles cases in adult groups, albeit small in number, indicate that the previously neglected adult group may need to be brought into vaccine coverage to achieve WHO's goal of measles eradication from the globe. In this study, we develop a novel transmission dynamics model to describe measles cases in adults and children to evaluate the role of adult infection in persistent measles cases and vaccination programs for eradication. Analysis of our model, validated by measles cases from outbreaks in Nepal, provides the vaccination reproduction number (conditions for measles eradication or persistence) and the role of contact network size. Our results highlight that while children are primary targets for measles outbreaks, a small number of infections in adults may act as a reservoir for measles, causing obstacles to eradication. Furthermore, our model analysis shows that while impactful controls can be achieved by children-focused vaccines, a combined adult-child vaccination program may help assert eradication of the disease.
尽管有成功的疫苗可用，但近年来麻疹疫情仍频繁发生，推测原因是疫苗接种实施不当。此外，成人组中的麻疹病例数量虽少，但表明之前被忽视的成人组可能需要纳入疫苗接种范围，以实现世界卫生组织在全球消除麻疹的目标。在本研究中，我们开发了一种新型传播动力学模型来描述成人和儿童中的麻疹病例，以评估成人感染在持续性麻疹病例和根除疫苗接种计划中的作用。通过尼泊尔疫情中的麻疹病例验证的我们的模型分析，给出了疫苗接种繁殖数（麻疹根除或持续存在的条件）以及接触网络规模的作用。我们的结果强调，虽然儿童是麻疹疫情的主要目标，但成人中的少量感染可能成为麻疹的储存库，给根除工作造成障碍。此外，我们的模型分析表明，虽然以儿童为重点的疫苗接种可以实现有效的控制，但成人和儿童联合疫苗接种计划可能有助于确保根除该疾病。
