Prenatal education for congenital toxoplasmosis

 

Abstract

Background

Congenital toxoplasmosis is considered a rare but potentially severe infection. Prenatal education about congenital toxoplasmosis could be the most efficient and least harmful intervention, yet its effectiveness is uncertain.

Objectives

To assess the effects of prenatal education for preventing congenital toxoplasmosis.

Search methods

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (November 2007), CENTRAL (The Cochrane Library 2007, Issue 3), MEDLINE (1966 to November 2007), EMBASE (1980 to November 2007), CINAHL (1982 to November 2007), LILACS (1982 to November 2007) IMEMR (1984 to November 2007), and reference lists of relevant papers, reviews and websites.

Selection criteria

Randomized and quasi-randomized controlled trials (RCT) of all types of prenatal education on toxoplasmosis infection during pregnancy.

Data collection and analysis

Three authors independently assessed study quality and extracted data.

Main results

One cluster-randomized controlled trial (432 women) met the inclusion criteria. However, the overall methodological quality was poor. The authors did not report measure of association but only provided P values (P less than 0.05) for all outcomes. The authors concluded that prenatal education can effectively change pregnant women's behavior as it increased pet, personal and food hygiene. There are no randomized trials on the effect of prenatal education on congenital toxoplasmosis rate, or toxoplasmosis seroconversion rate during pregnancy, but three observational studies consistently suggest that prenatal education might have a positive impact on these outcomes.

Authors' conclusions

Even though primary prevention of congenital toxoplasmosis is considered a desirable intervention, given the lack of related risks compared to secondary and tertiary prevention, its effectiveness has not been adequately evaluated. There is very little evidence from RCTs that prenatal education is effective in reducing congenital toxoplasmosis even though evidence from observational studies suggests it is. Given the lack of good evidence supporting prenatal education for congenital toxoplasmosis prevention, further RCTs are needed to confirm any potential benefits and to further quantify the impact of different sets of educational intervention.

 

Plain language summary

Prenatal education for congenital toxoplasmosis

Toxoplasmosis infection is caused by a parasite, Toxoplasma gondii. Eating raw or insufficiently cooked meat, not washing hands thoroughly after handling raw meat or gardening, or contact with cats' faeces (directly or indirectly through the soil, or possibly contaminated raw vegetables or fruits) can cause infection. Usually it is asymptomatic and self-limited. If pregnant women have not previously been exposed to the parasite and developed antibodies (immunoglobulins) while pregnant, the infection can be transmitted from the mother to the fetus (congenital toxoplasmosis). This is rare but has potentially serious effects of malformation, mental retardation, deafness and blindness of the infected infant, intrauterine death or stillbirth. The probability of infection is greater during the third trimester but the risk of the fetus developing major clinical signs is greater earlier in pregnancy. Primary prevention or population surveillance involves educating the general public, filtering water, improving farm hygiene to reduce animal infection, and offering prenatal education to pregnant women or women of reproductive age so that they can avoid toxoplasmosis through adopting simple behavioral measures. Evidence supporting prenatal education to prevent congenital toxoplasmosis is limited. It does indicate that prenatal education can change pregnant women's behavior to avoid risk factors for toxoplasmosis infection during pregnancy. The one controlled trial identified by the review authors was from Canada and involved 432 women who were randomly assigned to a 10 minute presentation about toxoplasmosis prevention that focused on cat, food and personal hygiene during their first prenatal class, or to their usual prenatal class.

Losses to follow up of the women participating in prenatal classes were high and 285 completed the post test questionnaire in the third term of pregnancy. Only 5% of the intervention women recalled having obtained specific information on toxoplasmosis prevention during prenatal classes.

We did not find any randomized trials providing data on change of congenital toxoplasmosis rate or exposure to toxoplasmosis in the blood (and seroconversion) during pregnancy.

 

摘要

背景

先天性弓蟲症(congenital toxoplasmosis)的產前教育

先天性弓蟲症是罕見但嚴重的感染。有關先天性弓蟲症的產前教育是最有效且傷害最少的介入方式，但是其效果還不確定。

目標

評估預防先天性弓蟲症的產前教育之效果。

搜尋策略

我們搜尋Cochrane Pregnancy和Childbirth Group's Trials Register (2007年11月)、CENTRAL (The Cochrane Library 2007, Issue 3)、MEDLINE (1966年2007年11月)、EMBASE (1980年2007年11月)、CINAHL (1982年2007年11月)、LILACS (1982年2007年11月)、IMEMR (1984年2007年11月)以及相關報告的參考文獻、文獻回顧與網站。

選擇標準

懷孕時有關弓蟲症感染的各種產前教育之隨機與半隨機控制試驗。

資料收集與分析

3位作者獨立評估研究品質與摘錄資料。

主要結論

1篇群聚隨機控制試驗(432名婦女)符合納入規範，不過，整體方法學品質不佳。作者們並未報告各種預後的關聯性，只有提供P值(P＜0.05)。作者們結論表示，產前教育可有效改變孕婦的行為來加強寵物、個人與食物衛生。沒有隨機試驗探討產前教育對於先天性弓蟲症比率、懷孕時弓蟲症血清轉化率的效果，但是有3篇觀察型研究一致認為，產前教育對於這些結果有正面影響。

作者結論

雖然先天性弓蟲症之首要預防被視為需要的介入方式，但是缺乏相較於次級和三級預防的相關風險，其效果未被適當評估。很少有隨機控制試驗的證據指出產前教育可有效降低先天性弓蟲症，證據多數來自觀察型研究。因為缺乏良好證據支持預防先天性弓蟲症的產前教育，後續須以隨機控制試驗來確認任何可能的好處，並量化不同產前介入方式的影響。

翻譯人

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

先天性弓蟲症的產前教育：弓蟲症感染是由弓漿蟲(Toxoplasma gondii)這種寄生蟲引起的，食用生肉或未煮熟的肉、處理生肉或園藝工作後沒有徹底洗手、接觸到貓大便(直接或透過土壤間接接觸、或生鮮蔬果受到污染)都會引起感染。它通常是無症狀且自限。如果孕婦未曾曝露於此寄生蟲而沒有在懷孕時產生抗體(免疫球蛋白)，弓漿蟲就會經由母親纏到造成胎兒而造成之感染(先天性弓蟲症)。這相當罕見，但會造成嚴重的畸形、心智遲緩、聾與盲、子宮內死亡或死產。在第3孕期的感染可能性較大，但是懷孕初期感染時會造成的胎兒產生臨床症狀的風險最大。主要預防或監控方式包括公眾教育、過濾水質、改善農場衛生以減少動物感染、提供孕婦或孕齡婦女適當產前教育，讓她們可以藉由簡單的行為方式避免接觸弓漿蟲。支持產前教育以預防先天性弓蟲症之證據有限。一般認為產前教育可改變孕婦的行為而避免懷孕期間感染弓漿蟲的風險因素。本文獻回顧納入的是一篇加拿大的控制試驗，包括了432名婦女，隨機指派，在第一次產前課程時接受10分鐘有關弓蟲症預防之演講，聚焦在貓、食物與個人衛生，或者在一般產前課程中進行。參加產前課程者之中，失去追蹤比率相當高，只有285人在第3懷孕期完成後測問卷。只有5% 的婦女認為在產前課程獲得有關預防弓蟲症的特定資訊。我們並未發現有任何隨機試驗提供有關先天性弓蟲症的改變、懷孕時血液(和血清轉化)中有弓漿蟲等資料。