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

   
Editorial

Indian Pediatr 2014;51: 870-872

Utility of Hepatitis B Vaccination in India

Pediatrician’s Perspective

 

Rajeev Kumar and Jacob Puliyel

Department of Pediatrics, St Stephens Hospital, Delhi, India.
Email: [email protected]


G
lobal health interventions are being scrutinized more closely than previously. According to an article published recently, the Center for Global Development in Washington is looking for evidence in real-life field conditions to ascertain whether large-scale health interventions have actually led to lower numbers of cases or deaths, and whether these improvements are sufficient to justify the costs [1]. This issue of Indian Pediatrics includes a paper on limited evaluation of the effect of inclusion of hepatitis B (HB) vaccine in childhood immunization program in India [2]. The authors carried out a serological survey of children aged 5 to 11 years in rural Andhra Pradesh; 2674 of those surveyed had received HB immunization and 2350 had not received such immunization. Babies who get infected with the hepatitis B virus (HBV) either develop antibodies to HBV [Anti-hepatititis B antibody to core antigen (AntiHBc) and Anti-hepatititis B antibody to surface antigen (AntiHBs)] and clear the organism from their system or else they become chronic carriers of hepatitis B antigen (HBsAg). Vaccination is meant to reduce the numbers who become chronic carriers. Three salient points emerge from their study:

1. Authors found that vaccination did not reduce hepatitis B carrier rate, which is the primary aim of the immunization program. The hepatitis B surface antigen positivity, which is an indicator of chronic HBV infection, was 0.15% among the vaccinated compared to 0.17% in those not vaccinated (P=0.855).

2. AntiHBc was present in 1.79% of the unvaccinated but also in 1.05% of the vaccinated. The absolute risk reduction (ARR) was 0.74%; 135 babies need to be vaccinated to prevent 1 child from getting infected with hepatitis B using this criterion. The authors note that this is a statistically significant reduction (Risk ratio 0.59, 95%CI 0.36-0.94). However, the clinical significance and utility of decreasing asymptomatic infection from 1.79% to 1.05% is questionable.

3. Vaccine-induced seroprotection (AntiHBs) is another useful surrogate of vaccine efficacy [3]. At 6 years of age, protective levels of anti-HBs antibody (10 mlU/mL) were present only in about 59% of those immunized. By 11 years, only 13% had protective levels. This is in stark contrast to reports from other countries where 95% of those vaccinated have protective levels and it drops to 92% at 40 years [4]. As also mentioned in this paper, few other studies have reported protective levels of 90% to 76% on follow up, 5 to 10 years later. The low antibody response in the present study correlates with low ARR against hepatitis described above.

Reasons for Low Vaccine Efficacy

The authors point out that the low antiHBc positivity rate among the unvaccinated indicates HBV transmission was low in the area, and it may be the reason they failed to find a reduction in hepatitis B carrier rate among the vaccinated. One-third of unvaccinated had developed antiHBsAg by 6 years of age which suggests that transmission of HB virus was not low in the area. It is comparable to world literature, that without vaccination, a third of the population get infected and the vast majority clear the infection [5]. The findings of the present study support the contention that Hepatitis B is widespread but it is a benign disease in India, possibly because of characteristics of the circulating virus strain and the genetic makeup of the population [6].

Viewing the same data of 33% antiHBs positivity among the unvaccinated, the authors speculate that these rural people may be getting Hepatitis B immunization surreptitiously, without entering it in their records. This seems a bit far-fetched and it seems more plausible that asymptomatic infection among the unvaccinated resulted in antiHBs positivity.

Other Issues

Two other factors must also be mentioned here when considering impact of Hepatitis B immunization in real-life conditions in the field:

a) The vaccine administered to babies in this study was a stand-alone Hepatitis B vaccine. It is known that this vaccine provokes a better antibody response than the combination Pentavalent vaccine, that is being administered currently. The efficacy with Pentavalent vaccine is likely to be even less than that reported in this paper [7].

b) The other factor that will impact outcomes in the field is the uptake of immunization. According to information obtained under the Right to Information Act, states with good surveillance systems like Goa and Kerala are reporting one death as adverse events following immunization (AEFI) per 4000 to 12000 babies immunized with the hepatitis B containing Pentavalent vaccine [8,9]. The District Level Household Survey in Tamil Nadu in 2012-13 has noted a decline in immunization coverage across districts which were considered to be well-performing in 2007-08 [10]. The number of fully immunized children has fallen in Tamil Nadu by as much as 25%. Adverse impact of the polio eradication campaign and social resistance in some states such as Tamil Nadu and Kerala due to reports of AEFI deaths following Pentavalent vaccine are being considered as possible explanations for this phenomenon [11]. Low uptake of vaccine will further erode the benefits.

If the findings of this study are replicated in other areas, it should prompt a re-evaluation of the need for this vaccine in the immunization program of the country.

Funding: None; Competing interests: None stated.

References

1. Cohen J. A hard look at global health measures. Science. 2014;345:1260-5.

2. Aggarwal R, Babu JJ, Hamalatha R, Reddy AV, Sharma D, Kumar T. Effect of inclusion of Hepatitis B vaccine in childhood immunization program in India. A retrospective cohort study. Indian Pediatr. 2014;51:875-9.

3. Jack AD, Hall AJ, Maine N, Mendy M, Whittle HC. What level of hepatitis B antibody is protective? J Infect Dis. 1999;179:489-92.

4. Schillie S, Murphy TV, Sawyer M, Ly K, Hughes E, Jiles R, et al; Centers for Disease Control and Prevention (CDC). CDC guidance for evaluating health-care personnel for hepatitis B virus protection and for administering postexposure management. MMWR Recomm Rep. 2013;62:1-19.

5. Indian Council of Medical Research. Minutes of the Expert Group Meetings on Hepatitis B and Hib Vaccines. March 2010. Available from: http://www.icmr.nic.in/minutes/Minutes%20Expert%20Group%20%20Hepatitis%20B%20 and%20Hib%20vaccines.pdf. Accessed September 25, 2014.

6. Liver Research Foundation. Hepatitis B: Out of the Shadows. Available from: http://www.liver-research.org.uk/liver-research-files/Hepatitis-B—Out-of-the-Shadows.pdf. Accessed September 29, 2014.

7. Kapoor AN, Tharyan P, Kant L, Balraj V, Shemilt I. Combined DTP-HBV vaccine versus separately administered DTP and HBV vaccines for primary prevention of diphtheria, tetanus, pertussis, and hepatitis B (Protocol). Cochrane Database Syst Rev. 2010;9:CD008658.

8. Pandey K. Are Some States Under-reporting Pentavalent Vaccine Deaths? Down to Earth 17/2/2014. Available from: http://www.downtoearth.org.in/content/are-some-states-under-reporting-pentavalent-vaccine-deaths. Accessed September 29, 2014.

9. Puliyel J. New models for public-private partnerships in health promotion. In: IDFC 12th India Infrastructure Report 2013-14: Road to Universal Health Coverage. New Delhi: Orient BlackSwan; 2014; p. 203-12.

10. Ministry of Health and Family Welfare. District Level Household and Facility Survey-4. State Fact Sheet: Tamil Nadu. Available from: http://www.iipsindia.org/pdf/pre%20bid%20conference%20combine%20PP.pdf. Accessed October 6, 2014.

11 Dasgupta R, Dasgupta P, Agrawal A. Decline in immunization coverage across well-performing districts in India: An urban conundrum? Indian J Pediatr. 2014;81:847-9.

 

Copyright © 1999-2014  Indian Pediatrics