Seroepidemiological Study on Trend of Helicobacter pylori Infection Rate in a small population

我们在小规模人群中进行了幽门螺杆菌感染率趋势的血清流行病学研究。我们于1987、1988、1992、1993和1997年在一个小城镇收集了大约6,000名年龄在30岁以上的居民的血清样品，并储存在冰箱中。采用酶免疫法（EIA）检测血清中幽门螺杆菌（Helicobacter pylori，Hp）IgG抗体。幽门螺杆菌感染阳性的判断标准是Ig-G抗体水平为1+或更高。1988年、1992年和1993年幽门螺杆菌感染率均低于1987年和1997年。这可能是由于冷冻前准备不足或冷冻期间条件差。1987年和1997年，男性的比率都高于女性。1987年和1997年，除80岁或以上的人外，各年龄组的死亡率都随着年龄的增长而增加。出生队列分析显示了同样的现象。从1987年到1997年，同一年龄组的具体年龄比率略有下降。1987年和1997年共检测533名居民，持续阳性率约为70%，持续阴性率约为20%。血清阳转率约5%，阴转率约6%。研究区域只有一家区域医院，医生在这10年中没有对幽门螺杆菌感染患者进行根除治疗。提示成年居民中幽门螺杆菌感染存在自发性血清转化，但在人群中所占比例较小。

We conducted a seroepidemiological study on trend of Helicobacter pylori infection rate in a small population. We collected serum samples from about 6,000 residents whose age were 30 years old or older in a small town in 1987,1988,1992,1993 and 1997 and had stored in freezers. We measured Ig-G antibody of Helicobacter pylori of the sera by EIA method. Positive Helicobacter pylori infection was judged by the Ig-G antibody level of 1+ or more. Helicobacter pylori infection rates in 1988,1992 and 1993 were lower than those in 1987 and 1997. This might be due to the poor preparation before freezing or poor condition during the freezing period. The rates in males were higher than in females in both 1987 and 1997. The age-specific rates increased with age except for those in 80 years old or more in both 1987 and 1997. Birth cohort analysis showed the same phenomenon. The age specific rates in same age groups slightly decreased from 1987 through 1997. Among 533 residents measured in both 1987 and 1997, the persistent positive rate was about 70% and the persistent negative was about 20%. The positive sero-conversion rate was about 5% and the negative was about 6%. There is only a regional hospital in the study area and physicians did not conduct the eradication therapy for patients with Helicobacter pylori infection in these 10 years. These suggest that there is a spontaneous sero-conversion of Helicobacter pylori infection among adult residents, though the proportion in population is small.