Martínez Ana, Broner Sonia, Torner Nuria, Godoy Pere, Batalla Joan, Alvarez Josep, Barrabeig Irene, Camps Neus, Carmona Gloria, Minguell Sofía, Sala Rosa, Caylà Joan, Domínguez Angela
Directorate of Public Health, Generalitat of Catalonia, Spain.
Hum Vaccin. 2011 Jan-Feb;7 Suppl:205-10. doi: 10.4161/hv.7.0.14598. Epub 2011 Jan 1.
Hepatitis A outbreaks have a major impact on public health services and involve case investigation and intervention measures to susceptible contacts. At the end of 1998 a universal vaccination program with a combined hepatitis A+B vaccine was started in Catalonia (Spain) in 12-years-old preadolescents. The objective of this study was to compare the characteristics of hepatitis A outbreaks in the periods before and after the introduction of the preadolescent vaccination program and to estimate the preventable fraction of cases associated to outbreaks. The incidence rates of outbreaks, cases and hospitalization associated with each outbreak were calculated. Two periods were considered: before (1991-1998) and after (2000-2007) the introduction of mass vaccination. The preventable fraction and 95% confidence intervals (CI) of cases associated with outbreaks was calculated. The rate of associated cases with outbreaks was higher in the period before the vaccination program than in the post vaccination period (1.53 per 100,000 person-year vs 1.12 ; p< 0.001), but the rate of hospitalization was greater in the period after the introduction of vaccination program than in the period previous to vaccination (0.70 per million persons-year vs 0.08; p< 0.001). The preventable fraction of cases associated to outbreaks was 19.6%(95%CI 6.7-32.5) in the 0-4 years group and 16.7% (95% CI 6.0-27.5) in the 5-14 years group, but the highest figure (38.6%; 95%CI 21.3-55.9) was observed in the 15-24 years age group. The estimated proportion of cases associated with outbreaks that would theoretically have been prevented with the vaccination program suggests that substantial benefits have been obtained in Catalonia in people aged less than 25 years.
甲型肝炎暴发对公共卫生服务有重大影响，涉及病例调查以及针对易感接触者的干预措施。1998年底，西班牙加泰罗尼亚地区针对12岁的青春期前儿童启动了一项使用甲型和乙型肝炎联合疫苗的普遍接种计划。本研究的目的是比较青春期前儿童接种计划实施前后甲型肝炎暴发的特征，并估算与暴发相关病例的可预防比例。计算了每次暴发的发病率、病例数和住院率。研究考虑了两个时期：大规模接种前（1991 - 1998年）和接种后（2000 - 2007年）。计算了与暴发相关病例的可预防比例及95%置信区间（CI）。接种计划实施前与暴发相关的病例率高于接种后时期（每10万人年1.53例对1.12例；p < 0.001），但接种计划实施后时期的住院率高于接种前时期（每百万人年0.70例对0.08例；p < 0.001）。0 - 4岁组与暴发相关病例的可预防比例为19.6%（95%CI 6.7 - 32.5），5 - 14岁组为16.7%（95%CI 6.0 - 27.5），但在15 - 24岁年龄组中观察到最高值（38.6%；95%CI 21.3 - 55.9）。理论上通过接种计划可预防的与暴发相关病例的估计比例表明，加泰罗尼亚地区25岁以下人群已获得显著益处。
