Department of Microbiology, Ahmadu Bello University, Zaria, Nigeria.
Trans R Soc Trop Med Hyg. 2013 Oct;107(10):627-30. doi: 10.1093/trstmh/trt072. Epub 2013 Aug 19.
Hepatitis A is an infectious viral disease, caused by hepatitis A virus (HAV), endemic in many developing countries. A recent review of the global prevalence of HAV infection and susceptibility by the WHO had few data on the seroprevalence of HAV in Nigeria. This study was designed to determine the seroprevalence of HAV among schoolchildren and adolescents in Kaduna State and to identify factors associated with seropositivity.
Questionnaires were administered to 403 participants aged 2-19 years, and blood samples were collected during April-July 2009 and screened for anti-HAV IgG using an anti-HAV IgG enzyme immunoassay kit. χ(2) and Fisher's exact tests were used to identify variables associated with the presence of anti-HAV IgG.
The mean ± SD age of the study population was 11.7 ± 3.2 years. Of the 403 serum samples, 29 were positive for HAV, giving an overall seroprevalence of 7.2% (95% CI 4.9-10.2%) among the study population. Seropositivity with respect to age ranged from 4.6% (10/218; 95% CI 2.2-8.3%) in the 11-15 years age group to 30% (3/10; 95% CI 6.7-65.3%) in the ≤5 years age group. Anti-HAV seropositivity was associated with sewage disposal methods and parents' educational level (p < 0.05).
This study shows that the majority of the study population lacked natural immunity (anti-HAV IgG). This low HAV exposure may be attributed to improvements in sanitary conditions and socioeconomic status. Further research involving an older population in different parts of the country is required to determine the current epidemiological pattern of HAV.
甲型肝炎是一种由甲型肝炎病毒（HAV）引起的传染病，在许多发展中国家流行。世界卫生组织最近对 HAV 感染和易感性的全球流行情况进行了审查，发现有关尼日利亚 HAV 血清流行率的数据很少。本研究旨在确定卡杜纳州学童和青少年的 HAV 血清流行率，并确定与血清阳性相关的因素。
对 403 名 2-19 岁的参与者进行问卷调查，并在 2009 年 4 月至 7 月期间采集血样，使用抗 HAV IgG 酶联免疫吸附试剂盒检测抗 HAV IgG。χ²和 Fisher 确切检验用于确定与抗 HAV IgG 存在相关的变量。
研究人群的平均年龄±标准差为 11.7±3.2 岁。在 403 份血清样本中，有 29 份 HAV 阳性，总体血清阳性率为 7.2%（95%可信区间 4.9-10.2%）。血清阳性率与年龄有关，年龄在 11-15 岁组为 4.6%（10/218；95%可信区间 2.2-8.3%），在≤5 岁组为 30%（3/10；95%可信区间 6.7-65.3%）。抗 HAV 血清阳性与污水排放方式和父母的教育程度有关（p<0.05）。
本研究表明，大多数研究人群缺乏自然免疫力（抗 HAV IgG）。HAV 暴露率低可能归因于卫生条件和社会经济状况的改善。需要在该国不同地区进行涉及更年长人群的进一步研究，以确定 HAV 的当前流行病学模式。
