Testing of IgG and IgM against Rubella Virus in School Girls and Pregnant
Women in Hanoi where an Outbreak had occurred
Nguyen Van Bang
1*
, Nguyen Thi Van Anh
2
, Vu Thi Tuong Van
3
, Dao Thi Hop
4
, Nguyen Van Thuong
5
and Elizabeth Elliott
6
1
Department of Pediatrics, Hanoi Medical University, Vietnam
2
Department of Medical Education and Skills Laboratory, Hanoi Medical University, Vietnam
3
Department of Microbiology, Bach Mai University Hospital, Vietnam
4
Department of Gynecology and Obstetrics, French Hospital in Hanoi, Vietnam
5
Pediatric Department, Saint Paul Hospital, Hanoi, Vietnam
6
Clinical School, Children Hospital at Westmead, Sydney University, Australia
*
Corresponding author: Nguyen Van Bang, Pediatric Department, Hanoi Medical University, No 299 Giap Bat Street, Hoang Mai District, Hanoi, Vietnam, Tel: +84 4
38641241, +84 903293212; E-mail: hongbang52@yahoo.com, nguyenvanbang@hmu.edu.vn
Rec date: Apr 17, 2014, Acc date: May 03, 2014, Pub date: May 10, 2014
Copyright: © 2014 Nguyen VB, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Background: Congenital Rubella Syndrome (CRS) is preventable illness but stays frequent in developing
countries where rubella vaccination is not incorporated in national program of vaccination like in Vietnam actually.
Aims: This study aimed at obtaining baseline information on acquired immunization status of school girls as well
as the rate of susceptibility and rubella infection in pregnant women around a rubella outbreak in Hanoi, Vietnam.
Population and methods: During and after the rubella outbreak in 2011, sera from 136 school girls (aged from
14 to 17 years) and 140 pregnant women in Hanoi French hospital were tested for rubella-specific IgG and for
rubella-specific IgM (only in pregnant women) by the technique of Electro-Chemiluminescence Immunoassay
(ECLIA) (Roche Diagnostics) with cut-off value ≥ 10 IU/mL for IgG and ≥ 0.3 IU/mL for IgM.
Results: Rubella-specific IgG antibodies was positive in 125/136 (91.9%) school girls and 119/140 (85%)
pregnant women, with strong-to-extreme concentration in 86/136 (63.2%) school girls versus 19/140 (13.6%) in
pregnant women (p<0.002). Rubella-specific IgG was negative (susceptible to rubella infection) in 21/140 (15%) and
rubella-specific IgM antibodies was positive in 27.9% (39/140) pregnant women, of whom 38 (27.1%) a co-existence
of rubella-specific IgG and IgM were documented.
Conclusions: This preliminary, baseline per/post epidemic information showed a high rate of acquired
immunization in female adolescents but also high rate of susceptibility and very high rate of rubella infection in
pregnant women, warranting further comprehensive studies to determine robust, nationwide epidemiological data
prior to establishing the national program of immunization against rubella and identify appropriate methods for CRS
surveillance in Vietnam.
Keywords: Acquired immunization; Rubella infection; School girls;
Pregnant women; Congenital Rubella Syndrome (CRS)
Introduction
Rubella usually is a mild, febrile rash illness in children and adults.
However, infection early in pregnancy, particularly during the first 16
weeks of gestation can result in miscarriage, stillbirth or an infant born
with Congenital Rubella Syndrome (CRS) [1-4]. The World Health
Organization (WHO) estimates that around 238,000 children are born
with CRS every year, the majority of whom live in developing
countries [4-9]. The frequency of CRS varies in different parts of the
world, depending on levels of naturally acquired immunity,
overcrowding and immunization policies and practices [10-13].
During epidemics of rubella, CRS has been reported in 0.6-2.2/1,000
live births [6-7]. The WHO and the Children’s Vaccine Initiative have
produced guidelines for surveillance of CRS and rubella [5-13], and
targets for accelerated rubella control and CRS prevention have been
established by the Western Pacific Region (WPR) [11-13]. WHO
guidelines also recommend that, for countries in Stage 1 (planning for
rubella vaccination), the surveillance should focus not only on
establishing case-based CRS detection [6,10-13] but also on serological
status of rubella in childbearing age and pregnant women [6,7,14-20].
In Vietnam, where rubella virus of genotype 2B circulates [21], the
rubella vaccine, well-known for its effectiveness [5,10-13], has not
been incorporated yet into the national immunization schedule. In late
2010 and early 2011, an epidemic of rubella had been confirmed
[21-23]. Consequently, at least 7,259 cases of rubella had been
identified resulting in 189 CRS cases in 2012 rubella outbreak in
Vietnam, according to National Health Authority Reports to WHO
[11]. However, few studies conducted antenatal serosurveys to assess
the proportion of women at risk for rubella infection in pregnancy
[22]. In view of efforts to incorporate rubella vaccine into the national
immunization program in Vietnam, it is prerequisite to establish the
Virology & Mycology
Van Bang, et al., Virol & Mycol 2014, 3:2
DOI: 10.4172/2161-0517.1000130
Research Article Open Access
Virology & Mycology
ISSN:2161-0517 VMID, an open access journal
Volume 3 • Issue 2 • 1000130
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ISSN: 2161-0517