背景:甲型肝炎病毒(HAV)感染通常在幼儿中无症状,但是大多数青少年和成年人会出现从恶心和疲倦到急性肝衰竭甚至死亡的症状。老年人和已有肝病的人患严重疾病的风险更高。建议在低HAV流行水平的地区进行免疫接种,即,人们在以后的生活中被感染。在菲律宾,缺乏有关HAV感染的最新流行病学数据。这项研究的目的是评估年龄特异性血清阳性率并评估与HAV血清阳性相关的危险因素。
方法:招募来自两个地理区域(城市和农村)的人,并按年龄组进行分层。用化学发光微粒免疫测定法测量HAV特异性免疫球蛋白G(IgG)抗体。社会人口统计学参数,肝炎病史,疾病知识,卫生措施和环境卫生通过专门制定的问卷进行评估.使用Kaplan-Meier曲线估计群体免疫中点年龄(AMPI)。进行Logistic回归分析以确定与HAV血清阳性有统计学显著性相关(p<0.05)的因素。
结果:总体而言,1242名参与者被纳入分析;250/602名(41.5%)来自城市地区的参与者和283/640名(44.2%)来自农村地区的参与者的HAVIgG抗体检测呈阳性。农村和城市地区的AMPI分别为35岁和37岁,分别。高等教育与较低的HAV血清阳性患病率相关,虽然过去5年不在同一地区生活,经常食用街头食品和排便后不洗手与HAV血清阳性的可能性较高相关.
结论:结果表明菲律宾的HAV地方性低。与HAV血清阳性相关的因素正在旅行,消费街头食品和缺乏基本的卫生手势。免疫接种可能是保护脆弱人群免受严重甲型肝炎疾病的一种选择。
甲型肝炎病毒(HAV)通过食用受污染的食物或水或与感染者密切接触,通过粪便-口腔途径传播。在儿童中,HAV通常无关紧要,但是在成年人和现有肝病患者中,HAV感染可导致严重症状甚至死亡。在儿童时期大多数人患上肝炎的地区(高流行),不需要接种疫苗,因为人们在感染后获得终身免疫力。在低和中度HAV流行的地区,患者在以后的生活中可能仍有感染风险,因此可以考虑接种疫苗以预防严重的HAV疾病及其相关并发症.在菲律宾,目前的流行程度是未知的。这项研究的目的是确定菲律宾的流行水平,并确定HAV感染的危险因素。我们测量了以前感染HAV的人群(按年龄组)的比例。结果显示,到5岁时,<20%的研究人群被HAV感染。到城市人口37岁,农村人口35岁,50%的人HAV抗体检测呈阳性,表明以前的感染。这意味着菲律宾的HAV地方性较低。HAV血清阳性的危险因素是旅行,经常吃街头食品,排便后不洗手。在菲律宾,接种HAV疫苗可能会受益,特别是在生命早期,以防止成年后最严重的后果。
BACKGROUND: Infection with hepatitis A virus (HAV) is often asymptomatic in young children, but most adolescents and adults will have symptoms ranging from nausea and tiredness to acute liver failure and even death. The risk of severe disease is higher in older adults and people with pre-existing liver disease. Immunization is recommended in regions with low HAV endemicity levels, i.e., where people get infected later in life. In the Philippines, recent epidemiologic data on HAV infection are lacking. The objective of this study was to assess age-specific seroprevalence and evaluate risk factors associated with HAV seropositivity.
METHODS: People from two geographic areas (urban and rural) were recruited/enrolled and stratified by age group. HAV-specific immunoglobulin G (IgG) antibodies were measured with a chemiluminescent microparticle immunoassay. Sociodemographic parameters, hepatitis medical history, disease knowledge, hygiene measures and sanitation were assessed via a purpose-made questionnaire. Age at midpoint of population immunity (AMPI) was estimated using Kaplan-Meier curves. Logistic regression analyses were carried out to determine factors that were statistically significantly associated (p < 0.05) with HAV seropositivity.
RESULTS: Overall, 1242 participants were included in the analysis; 250/602 (41.5%) participants from urban regions and 283/640 (44.2%) participants from rural regions tested positive for HAV IgG antibodies. AMPI was 35 and 37 years for the rural and urban region, respectively. Higher education was associated with lower HAV seropositivity prevalence ratios, while not living in the same region for the last 5 years, regularly consuming street food and lack of handwashing after defecation were associated with a higher likelihood of HAV seropositivity.
CONCLUSIONS: Results suggest that HAV endemicity is low in the Philippines. Factors associated with HAV seropositivity were traveling, consuming street food and lack of basic hygienic gestures. Immunization might be an option to protect vulnerable populations against severe hepatitis A disease.
Hepatitis A virus (HAV) is transmitted via the fecal-oral route through consumption of contaminated food or water or by close contact with an infected person. In children, HAV is usually of no concern, but in adults and people with existing liver disease, HAV infection can lead to severe symptoms and even death. In areas where most people get hepatitis during childhood (high endemicity), vaccination is not required, since people acquire life-long immunity after infection. In regions with low and intermediate HAV endemicity, people may remain at risk of infection later in life and vaccination could be considered to prevent severe HAV disease and its associated complications. In the Philippines, the current endemicity level is unknown. The goal of this study was to determine the endemicity level in the Philippines and to determine risk factors for HAV infection. We measured the proportion of people (by age group) who had previously been infected with HAV. Results showed that by age of 5 years < 20% of the study population was infected by HAV. By the age of 37 years in the urban population and 35 years in the rural population, 50% of people tested positive for HAV antibodies, indicating previous infection. This means that the Philippines has low HAV endemicity. Risk factors for HAV seropositivity were traveling, regularly eating street food and not washing hands after defecation. Vaccination against HAV might be of benefit in the Philippines, especially early in life to prevent most severe outcomes in adulthood.