台灣東部山地原住民(排灣族、布農族和阿美族)弓蟲抗體陽性率與
年齡層和性別關係之探討
Study of correlation between ages and sexes in
seroprevalence of Toxoplasma gondii infection among
mountain aborigines (Paiwan, Bunun, and Ames) in eastern Taiwan.
中文摘要
自1997 年 2 月至 1999 年 2 月間陸續至台東縣金鋒鄉排灣族、海端鄉布農族和長濱鄉阿美族 地區以隨機抽樣方式分別採集成人(金鋒鄉排灣族 390 人;海端鄉布農族 62 人;長濱鄉阿美族 99 人)和學童(金鋒鄉排灣族 174 人;海端鄉布農族 363 人; 長濱鄉阿美族 1 人)計 1089 個血液檢 體,先以乳膠凝集反應法(Latex Agglutination Test; Eiken, Japan)進行血清弓蟲抗體篩檢,
陽性血清樣本進一步以微粒酵素標幟免疫法(Microparticle Enzyme Immunoassay; MEIA;
IMx, Abbot, USA)定量 IgG 和 IgM 抗體。結果顯示以乳膠凝集反應法篩檢之原住民血清弓蟲 抗體陽性率依高低分別為長濱鄉阿美族33.0% (33/100) 、海端鄉布農族 29.7%(126/425) 和金鋒鄉排灣族28.7%(162/564) 。進一步以微粒酵素免疫分析法分析並定量 LA 陽性血清中 抗弓蟲的IgG 和 IgM 抗體,結果顯示原住民血清中抗弓蟲的 IgG 抗體陽性率依高低分別為長濱 鄉阿美族33.0%(33/100)、海端鄉布農族 19.8%(84/425)和金鋒鄉排灣族
19.0%(107/564);而血清中抗弓蟲的 IgM 抗體陽性率依高低分別為金鋒鄉排灣族
1.1%(6/504) 、長濱鄉阿美族 1.0% (1/100) 、海端鄉布農族 0.9%(4/425) 。三個不同 地區的原住民而言,性別在弓蟲抗體陽性率間(LAT 及 IgG)並無顯著性差異(P>0.05),而 小孩與成人以LAT 篩檢時亦無差異(P>0.05);但藉 ELISA 定量血清中抗弓蟲的 IgG 抗體成 人的抗體陽性率(25.2%)大於孩童(15.6%),且有明顯的差異(P<0.05);依年齡層而言 弓蟲抗體陽性率在三個族群間皆隨著年齡層上升弓蟲抗體陽性率有隨之增加的趨勢。依不同族性 別而言長濱鄉阿美族的男性弓蟲抗體陽性率(LAT 及 IgG 均為 51.2%)較女性弓蟲抗體陽性率
(LAT 及 IgG 均為 19.3%)高,且具有顯著性差異(P<0.05)。而金峰鄉排灣族及海端鄉布 農族在性別間則並無顯著性差異(P>0.05);金峰鄉的成人弓蟲抗體陽性率(LAT-32.1%;
IgG-24.4%)大於小孩(LAT-21.3%;IgG-7.0%),且有顯著性差異(P<0.05);而海端鄉 布農族則無顯著性差異(P>0.05)。因長濱鄉孩童血清檢體取樣太少,兩者之弓蟲抗體陽性率 則無法比較;除海端鄉布農族外,弓蟲抗體陽性率均有隨著年齡層增加而上升的的趨勢。
本研究的台灣東部的三個不同族群原住民的弓蟲抗體陽性率皆比平地人高(1986 年俞氏 -9.1%; 1994 年陳氏-12%),此似乎顯示了台灣東部地區原住民的生活環境或飲食習性隱藏 著感染弓蟲的危險因子,至於危險因子為何,則必須進一步去深入探討。
英文摘要
In this study, latex agglutination test (LAT) was used to screen sera
anti-toxoplasma antibodies of Paiwan aborigines in King-fong district, Bunun aborigines in Hei-don district, and Ames in Chang-bin district,Taitung county as a measure of exposure to the Toxoplasma gondii in eastern Taiwan. Out of 564 Paiwan aborigines, 425 Bunun aborigines and 100 Ames aborigines were tested, the positive rates were 28.7%, 29.7% and 33.0%, respectively. LAT positive sera were further confirmed for toxoplasmosis using microparticle enzyme immunoassay (MEIA). The crude positive rates for sera anti-toxoplasma IgG antibodies were 33.0% for Ames, 19.8% for Bunun and 19.0% for Paiwan, respectively. Except in Chang-bin district, the positive rates in males and females were not significantly different in two other districts (P>0.05). The seroprevalence in adults (24.4%) was significantly higher than that in children (7.0%) (P<0.05) in Paiwan, in contrast, no significant difference in seroprevalence was observed in the other two aboriginal groups. Note that the age pattern of prevalence of anti-Toxoplasma IgG antibodies is consistent with increasing duration of exposure to Toxoplasma gondii with age in those aborigines in eastern Taiwan.