UNASSIGNED: A dynamic age-structured SEIRV (susceptible-exposed-infectious-recovered-vaccinated) compartmental model was developed and calibrated using demographic, seroprevalence, vaccination, and epidemiological data from different regions of the Russian Federation. This model was used to project various epidemiological measures.
UNASSIGNED: The projected national average age at the midpoint of population immunity increases from 40 years old in 2020 to 50 years old in 2036 and is shifted even further to the age of 70 years in some regions of the country. An increase of varying magnitude in the incidence of symptomatic HAV infections is predicted for all study regions and for the Russian Federation as a whole between 2028 and 2032, if the HAV vaccination coverage level remains at the level of 2022. The national average vaccination coverage level required to achieve a symptomatic HAV incidence rate below 1 case per 100,000 by 2032 was calculated to be 69.8% if children aged 1-6 years are vaccinated following the implementation of a UMV program or 34.8% if immunization is expanded to children aged 1-17 years.
UNASSIGNED: The developed model provides insights into a further decline of herd immunity to HAV against the background of ongoing viral transmission. The current favorable situation regarding hepatitis A morbidity is projected to be replaced by an increase in incidence rates if vaccination coverage remains at the current levels. The obtained results support the introduction of a hepatitis A UMV strategy in the Russian Federation.
■开发了动态年龄结构的SEIRV(易感-暴露-感染-恢复-接种疫苗)隔室模型,并使用人口统计进行了校准,血清阳性率,疫苗接种,和来自俄罗斯联邦不同地区的流行病学数据。该模型用于预测各种流行病学措施。
■预计处于人口免疫中点的全国平均年龄从2020年的40岁增加到2036年的50岁,并且在某些地区进一步转移到70岁。国家。如果HAV疫苗接种覆盖率保持在2022年的水平,则在2028年至2032年之间,所有研究地区和整个俄罗斯联邦的症状性HAV感染发病率预计将出现不同程度的增加。如果在实施UMV计划后接种1-6岁儿童,则到2032年达到每10万例有症状的HAV发病率低于1例的全国平均疫苗接种覆盖率为69.8%,如果将免疫范围扩大到1-17岁儿童,则为34.8%。
■开发的模型在持续病毒传播的背景下提供了对HAV的群体免疫力进一步下降的见解。如果疫苗接种覆盖率保持在目前水平,目前甲型肝炎发病率的有利情况预计将被发病率的增加所取代。获得的结果支持在俄罗斯联邦引入甲型肝炎UMV策略。