Factors affecting the compliance of the antenatal hepatitis B screening programme in Italy
Introduction
Perinatal transmission of hepatitis B virus (HBV) plays an important role in the maintenance of the reservoir of chronic hepatitis B surface antigen (HBsAg) carriers among human beings. Women who are HBsAg carriers reproduce normally, infecting their offspring and perpetuating the cycle of perinatal infection. Thus, even in the western countries, where perinatal transmission affects to a lesser extent the entire pool of HBV carriers, immunisation of new-borns of HBsAg positive mothers is of paramount importance to break the cycle of HBV infection. However, immunisation at birth of new-borns of HBsAg positive mothers is a difficult target to achieve because it requires screening of all pregnant women. The alternative to screening pregnant women is to give a birth dose of vaccine to all new-borns, which is the preferred strategy in high endemic (mostly developing) countries.
In Italy, since 1984 HBsAg screening for pregnant women during the last trimester of pregnancy and vaccination against hepatitis B for new-borns of HBsAg positive mothers have been strongly recommended. In 1991, this policy became compulsory by law. Infants born of HBsAg carrier mothers are given hepatitis B immune globulin (HBIG) and vaccine at birth.
The aim of this study was to evaluate the effectiveness of this vaccination policy in a national sample of pregnant women. Moreover, because in Italy, as well as in other western Europeans countries, an important immigration flow from developing countries has occurred during the last few years, we have also evaluated the effectiveness of the programme for new-borns of foreign mothers. Because the immigration flow from developing countries has become very common in the developed world, the results of this study might be useful even for western countries other than Italy.
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Materials and methods
The study was carried out in six Italian regions: Piemonte, Emilia Romagna (north), Marche (centre), Puglia, Campania (south), Sardegna (island).
The study population consisted of pregnant women consecutively recruited during a 2 month period in public and private hospitals of the above mentioned regions.
Hospitals were chosen on the basis of spontaneous participation. Data were collected by a questionnaire containing information on socio-demographic characteristics and HBsAg status of pregnant
Results
During the study period 12129 pregnant women were enrolled; 271 of them resulted previously vaccinated against hepatitis B and thus excluded from the study. Out of the 11858 pregnant women eligible, 10881 (91.8%) attended HBsAg antenatal screening. The overall HBsAg prevalence was 1.7% (CI 95%: 1.4–1.9); it was 1.4% (CI 95%: 1.2–1.7) in women born in Italy but 5.9% (CI 95%: 4.1–8.1) in those born in eastern Europe, central and south America, Asia and Africa (Table 1). The frequency (%) of lack
Discussion
In order to avoid bias due to different socio-economic conditions of pregnant women both public and private hospitals have been recruited. Moreover, the consecutive manner of recruitment of subjects may have excluded bias due to selective factors, if any. Thus, despite hospitals were not randomly selected the population studied may ensure a good representativeness of pregnant women in Italy. The 1.4% HBsAg prevalence rate found among Italian pregnant women is much lower than the corresponding
Acknowledgements
Divisioni di Ostetricia e Ginecologia degli Ospedali di Urbino, Pesaro, Fano, Senigallia, Jesi, Fabriano, Ancona, Macerata, San Severino Marche, Civitanova Marche, Fermo, San Benedetto Del Tronto, Ascoli Piceno.
D. Protano, Servizio di Epidemiologia e Prevenzione ASL CE 1; Direzioni Sanitarie dei Presidi Ospedalieri di Maddaloni, Piedimonte Matese, Marcianise; Direzioni Sanitarie delle Cliniche Private di S. Luca, S. Anna, Villa del Sole, S. Michele. A. Gennari, Presidio Ospedaliero di Scafati
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