Home            Past Issues            About IP            About IAP           Author Information            Subscription            Advertisement              Search  

   
short communication

Indian Pediatr 2009;46: 1005-1008

Hepatitis B Prevalence during Pregnancy


S Chatterjee, K Ravishankar1, R Chatterjee2, A Narang3 and A Kinikar4

From Department of Pediatrics, Calcutta Medical College, Kolkata; 1Department of Neonatology,
Nilofer Hospital, Hyderabad; 2Department of Pediatrics, NRS Medical College, Kolkata;
3Department of Pediatrics, PGIMER, Chandigarh; and 4BJ Medical College, Pune, India.

Correspondence to: Dr Sukanta Chatterjee, 889 A, Lake Town, Kolkata 700 089, West Bengal, India.
Email: [email protected]

Manuscript received: April 11, 2008;
Initial review: May 9, 2008;
Accepted: September 9, 2008.

Published online: 2009 April 1.

PII:S097475590800224-2
 

Abstract

In order to determine the efficacy of a new hepatitis B immune globulin (HBIG), a phase 3, vertical transmission (mother to child) clinical interventional trial of hepatitis B virus (HBV) post exposure prophylaxis (PEP) was conducted at selected sites (n=15) throughout India. This required a large screening program for HBsAg positivity at prenatal clinics located in tertiary care hospitals. 36,379 pregnant women consented to be tested for Hepatitis B surface antigen (HBsAg) by Rapid Test and if positive-confirmed by ELISA. The weighted mean prevalence was 0.82% (95% CI, 0.72, 0.91). In conclusion, the prevalence of HBV carrier state during pregnancy in India in this study was low compared to previous reports.

Key Words: Hepatitis B, India, Pregnancy, Prevalence.


The carrier rate of Hepatitis B in India may vary in the different regions and is often quoted as being 4.7%(1,2). This is a mean of means of various studies and includes high risk populations(2). In a systematic review and meta-analysis of the prevalence of HBV infection in India, Batham, et al.(3) found that the point prevalence among non-tribal populations is 2.4% (corresponding to a chronic carrier rate of 1.9%). A great majority of the transmission of Hepatitis B in India and other developing countries occurs by vertical transmission from an infected carrier mother to the neonate, intrapartum or antenatally. The probability of developing the carrier state following HBV infection is greatest in early life and decreases with increasing age. Up to 90% of babies born to carrier mothers may become carriers and they are at a very high risk of developing chronic liver disease at a younger age(4). It has been estimated that up to 10% of the 350 million Hepatitis B chronic carriers worldwide arise in India. The burden of disease globally by vertical transmission is significant and this has led to the development of prophylaxis protocols adopted by many countries to decrease the pool of chronic carriers worldwide.

We conducted this study in 15 centers all over India to assess the prevalence of hepatitis B in pregnant women, mainly from non-tribal urban regions. This was a part of a larger study to demonstrate the safety and efficacy of a new hepatitis B immune globulin (HepaGamTM Cangene Corporation, Winnipeg, Manitoba, Canada) for post exposure prophylaxis.

Methods

This study was conducted from November 2003 to July 2006. For the purpose of this short communication, the epidemiological data from the screening tests performed in 36,379 pregnant women at 15 centers will be reported. Study centers were selected for the study on the basis of expected screenings or enrolments into the study. All pregnant women attending the antenatal clinics of these centers were screened for HBsAg at 5-9 months of gestation after informed consent was obtained. We used a rapid HBsAg test Kit (ACON Laboratories Inc, USA). A positive HBsAg test was confirmed by enzyme-linked immunosorbent assay (ELISA) after the pregnant woman signed the second part of an Informed Consent Form, consenting to her and her child’s participation in the study. Bioelisa HBsAg ELISA kit (Biokit, Barcelona, Spain) were used according to the manufacturer’s recommendations for HBsAg detection and absorbance was measured using an ELISA reader (MRX Microplate Reader, Dynatech, USA). The study was approved by DCGI (Permission No from DCGI: 12-51/2003-DC) and hospital ethics committees at each of the 15 institutions involved in this study, and the study was conducted in accordance with the ethical principles of the Declaration of Helsinki, and in accordance with the International Conference on Harmonization (ICH) of Technical Requirements for Registration of Pharmaceuticals for Human Use, E6 Good Clinical Practices: Consolidated Guidelines, Food and Drug administration (FDA) regulations and IEC-required procedures.

This large scale screening program in 15 tertiary care hospitals throughout India identified 398 (Table I) HBsAg positive women allowing some epidemiological data to be collected of the prevalence of HBV carrier state during pregnancy across all represented populations in India.

TABLE I



Prevalence of HBsAg at Prenatal Screening
Site Name Screened HBsAg  Prevalence
    Positive (%)
Pune 900 9 1
Chandigarh 2438 31 1.3
Panaji, Goa 1802 35 1.9
Bangalore* 1600 9 0.6
Bangalore+ 2205 8 0.4
Hyderabad 3051 52 1.7
Nagpur 932 5 0.5
Baroda 4099 27 0.7
Udaipur 472 0 0
Bangalore 432 20 4.6
Lucknow 3403 42 1.2
Kolkata 5022 56 1.1
Mumbai 3180 25 0.8
Kolkata 4316 42 1.0
Pune 2527 37 1.5
Total 36379 398

     Mean  1.09%
Weighted Mean  0.82%

* MS Ramaiah Medical College; +Vanivilas hospital, Bangalore Medical College.

Statistical analysis: The number of patients in each study center varies so the mean might deliberately over-represent or under-represent certain segments of the population. To restore balance of the number of patients enrolled in each center, the prevalence of HBsAg positivity was estimated using a weighted pooled point estimate along with a 95% confidence interval(5). Using this method, less weight will be placed on the study center with smaller number of enrolled patients and greater weight on the study center with larger number of enrolled patients. All calculations were performed using SAS® version 8.2. RNTMC screened 472 subjects and 0 tested HBsAg positive by screening test kit, the prevalence rate at this center was corrected to read 0.001 in order to include this data into the formula for weighted prevalence rates (Table I).

Results

Out of 36,379 pregnant women screened, 406 were HBsAg positive by rapid screen Further testing of these 406 positive tests determined that 398 were positive by ELISA. Thus the false positivity rate of the rapid screen is 2%.

The range of prevalence of HBsAg positivity in pregnant women varied from 0.4% (VHBMC, Bangalore) to 4.6% (SJMCH, Bangalore) and the overall mean prevalence of HBsAg positivity was 1.09% (95% CI 0.99-1.21) and the overall weighted mean of the prevalence of HBsAg positivity was 0.82% (95% CI 0.72-0.91). It has been confirmed that the high prevalence of HBsAg positivity at SJMCH in Bangalore was due to pre-selection of the population at this hospital since it is a referral center for "infectious cases" for the area. The mean prevalence of HBsAg positivity and weighted mean of the prevalence of HBsAg positivity excluding SJMCH prevalence rate was calculated to be 1.05% (95% CI 0.95-1.16) and 0.81% (95% CI 0.72-0.90), respectively.

Discussion

The prevalence of HBsAg positivity in pregnancy which was observed in this prospective, intervention study is less than 50% of previously reported non-tribal prevalence rates in systematic review of literature(2,3). The main limitation of the study is that the centers were located in urban areas and these centers were tertiary care referral centers. However, volunteer patients were not selected on the basis of referrals or walk-ins from the surrounding areas and not referrals except SJMCH, Bangalore. There is little change in weighted mean prevalence of HBsAg positivity excluding SJMCH (0.81%) compared to the overall weighted mean prevalence of HBsAg positivity including SJMCH (0.82%). This sample of patients screened and enrolled into the study may not be representative of the prevalence of hepatitis B infection in rural areas but is representative of the prevalence in urban areas.

The HBsAg rapid screen (Rapid Test Kit ACON Laboratories Inc, USA) was accurate in 98% of cases when used in a mass screening program of this nature and may be a cost effective means of screening pregnant women for HBsAg to identify at risk populations eligible for immunoprophylaxis of their neonates.

The weighted mean prevalence of HBsAg positivity in our multi-center prospective study was 0.82%, which is roughly less than one half of the previously reported point prevalence of HBsAg carrier state in non tribal populations in India(3). Consequently, the pharmaoeconomics of imple-menting an immuno-neprophylaxis program consisting of testing all pregnant mothers for HBsAg status and the administration of HBIG and recombinant hepatitis B vaccine within 12 hours of delivery to at risk neonates across the India may roughly be one half the previously estimated costs.

Contributors: All authors contributed to the study design, concept, literature search, data analysis and drafting of the manuscript.

Funding: Cangene Corporation, Winnipeg, Manitoba, Canada.

Competing interests: Cangene Corporation provided study grant to the participating 15 tertiary care hospitals in India.

Acknowledgments

All the investigators contributed greatly to the successful completion of this large clinical trial and the principal authors wish to recognize the team for this large scale screening effort and collection of the epidemiological data reported above (Annexure).

Annexure

1. India Pediatric Hepatitis B Immunoprophylaxis Study Group: K Srivastava, King George Medical College, Lucknow; D Gandhi, Government Medical College, Baroda; J Mondkar, LTM Medical College and General Hospital, Sion, Mumbai; S Bhat, St John’s Medical College and Hospital, Bangalore; A Bavdekar, Kem Hospital, Pune; P D’Souza, Goa Medical College, Panaji, Goa; P Maiya, MS Ramaiah Medical College and Hospital, Bangalore; D Balpande, India Gandhi Medical College, Nagpur; Dr. Shivananda, Bangalore Medical College and Vanivilas Hospital, Bangalore; Dr Shanti Mandowara, RNT Medical College, Udaipur, India.

2. India Obstetric Hepatitis B Immunoprophylaxis Study Group: M Sanghamita, Calcuta Medical College, Kolkata; G Devi, Nilofer Hospital, Hyderabad; D Bandyopandhyay, NRS Medical College, Kolkata; S Gopalan, PGIMER, Chandigarh; P Naphade, BJ Medical College, Pune; V Das, King George Medical College, Lucknow; L Chauhan, Government Medical College, Baroda; V Badhwar, LTM Medical College, Sion, Mumbai; A Mhaskar, St John’s Medical College and Hospital, Bangalore; R Otiv, KEM Hospital, Pune; P Nevrekar, Goa Medical College, Panaji, Goa; U Devi, MS Ramaiah Medical College and Hospital, Bangalore, India.

3. Cangene Corporation (Winnipeg, Manitoba, Canada) Hepatitis B Immunoprophylaxis Study Group: M Genereux, C Hall, C Sinclair, J Dixit, P Sadri and D Jain.

 


What This Study Adds?

• The Hepatitis B carrier state prevalence in women attending antenatal clinics in tertiary hospitals in urban areas in India is less than 1%.
 

References

1. Indian Association for Study of the Liver (INSAL). Hepatitis B in India; therapeutic options and prevention strategies-Consensus statement. Indian J Gastroenterol 2000; 19: C4-C66.

2. Lodha R, Kabra SK. Hepatitis B in India. A review of disease epidemiology. Indian Pediatr 2001; 38: 1322-1325.

3. Batham A, Narula D, TotejaT, Sreenivas V, Puliyel J. Systematic review and meta-analysis of prevalence of hepatitis B in India. Indian Pediatr 2007; 44: 663-674.

4. Joshi N, Kumar A, Immunoprophylaxis of hepatitis B virus infection. Indian J Med Microbiol 2001; 19: 172-183.

5. Cochrane Handbook for Systematic Reviews of Interventions, The Cochrane Collaboration. 2006: 127-128. Available from URL: http://cochrane.org/resources/handbook/Handbook4.2.6sep2006.pdf. Accessed on 19 October, 2009.
 

 

Copyright© 1999 by the Indian Pediatrics (Disclaimer)