Correspondence Address:
Samir Dasgupta
Profesor and Head, Department of Community Medicine, Medical College, Kolkata; Dean, West Bengal University of Health Sciences
India

Full Text

"With the exception of safe water, no other modality, not even antibiotics, has had such a major effect on mortality reduction……" [1]

When Edward Jenner first successfully 'vaccinated' against Small Pox he could hardly imagine that his experiment would change the future of public health forever. Immunization does prevent deaths and for last 3-4 decades it played a pivotal role in tackling infectious disease throughout the globe. Immunization is perhaps the most popular among all public health interventions, as revealed by the fact that more than 100 million children are vaccinated annually with more than 1000 million doses of different vaccines. [2]

Immunization can significantly contribute to achieve the United Nations Millennium Development Goal-4 (MDG-4), which aims to reduce under-five mortality by two thirds by 2015. Vaccine-preventable diseases are responsible for about one quarter of the 8.8 million deaths occurring annually among children under five years of age. Improving services to deliver traditional vaccines will reduce the number of deaths due to vaccine-preventable diseases. In addition, introducing new vaccines will help prevent some 1.3 million children deaths attributed to Pneumococcal, Meningococcal and Rotavirus disease. [3]

Palpable success of immunization in eradicating Small Pox scourge resulted in recognition of immense potential of immunization as a public health intervention. Routine immunization gradually figured in the priority list of national public health programmes and World Health Organization endorsed the process with advocacy for Expanded Programme on Immunization. As the national commitments materialized into action, results were evident. Globally, Measles Containing Vaccine (MCV) coverage rose from 16% in 1980 to 82% in 2007. [4] In the WHO South East Asian region, MCV started being introduced only after 1980, and coverage rose to 73% by 2007. Coverage level of DPT may be considered as one of the best indicator of health system performance in any country. Globally, DPT-3 coverage rose from 20% in 1980 to 81% in 2007. In the WHO South East Asian region, DPT-3 coverage rose from 7% to 69% during the same period. [4] [Table 1].{Table 1}

In addition to this, international coordination also reduced the variation in coverage across geopolitical situations. Impact of the program was evident with reduction in child mortality. Annually, estimated 2-3 million deaths and 1 million disabilities are averted by vaccination against Diphtheria, Pertusis, Tetanus and Measles, while another 600,000 future deaths are being prevented by HepB vaccination. Paralytic Polio is on the verge of eradication. Globally, Measles mortality has reduced by 74% from 750000 in 2000 to 197000 in 2007. [2] Further reduction in child mortality will need to bring other childhood killer diseases under the ambit of immunization programme. Vaccines are now available against Hib, Rubella, Meningococcal disease, Pneumococcal disease, Rotavirus diarrhoea, Japanese Encephalitis. With increasing market demand, rapid developments are taking place in vaccine research with encouraging clinical trial results on several vaccines against life-threatening infectious diseases. Vaccine industry is one of the fastest growing industry and between 2000 and 2008, global vaccine market almost tripled to US$17 billion. 112 countries have already introduced Hib vaccine in the routine immunization programme. 35 countries introduced Pneumococcal vaccine in routine programme. A new Meningococcal vaccine has the potential to eliminate meningitis, an epidemics that severely affect certain sub-Saharan countries. A first generation Malaria vaccine has demonstrated some level of efficacy in young children and may be available by 2015.

Besides newer vaccines, there have been commendable developments in newer technologies that may greatly influence the quality of immunization services. Vaccine Vial Monitor (VVM) is one such simple and effective tool, which can be used by health workers to detect cold chain failure, especially during outreach sessions in remote areas. Meticulous monitoring of temperature with newer technologies like electronic or electrical temperature/data logger would immensely benefit the program. GoI is considering introduction of this temperature monitoring tools in the coming years. It would be a boon for safeguarding cold chain system at different storage points especially for freeze sensitive vaccines like HepB, DPT, DT and TT in addition to tracking temperature maintenance till the point of delivery. Another novel advancement is the introduction of AD syringes. Introduction of ADS has resolved the problems of sterilization, particularly in resource poor settings and difficult areas, and will ensure injection safety to a great extent.

In spite of all these newer opportunities to control vaccine preventable diseases, challenge remains to transmit the benefits of scientific developments to all. Greatest challenge is to make services available particularly the vulnerable section of population. Globally, an estimated 24 million children remained unreached by the immunization programme in 2008; about three quarters of these unimmunized children live in ten countries: Chad, China, Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan and Uganda [5] . It is of serious concern that in South East Asian region, immunization coverage progress is plateauing in last few years and it has gone below the coverage level of poverty stricken African continent [6] .

To overcome these challenges, WHO and UNICEF recommended the main strategic areas in the Global Immunization Vision and Strategy 2006-2015. [3]



Immunize "hard to reach" infants and other age groups through a focus on the district level;Increase the availability and affordability of new life-saving vaccines;Deliver key health interventions, including insecticide-treated nets against malaria, vitamin A supplements, and deworming medicine during immunization contacts, especially for the "hard to reach" and,Strengthen cross-border collaboration and coordination to ensure a reliable supply of vaccine, sustainable financing of vaccination and epidemic preparedness.

India also geared up to face the challenge. Routine immunization activity in the country gained momentum in late 1970s with launching of EPI. Initial list of DPT, OPV, BCG and Typhoid-Paratyphoid vaccine was later modified to exclude Typhoid-Paratyphoid vaccine and include Tetanus for pregnant mothers in 1983. Program was modified in 1985 as Universal Immunization Programme to cover the entire country in a phased manner. Measles vaccination was included in 1985 and vitamin A supplementation was added in 1990. Coverage levels of different antigens have increased considerably. [Table 2] Effects were evident with steep fall in infant mortality rate from 129/1000 live births in 1971 to 55/1000 live births in 2007.{Table 2}

India has one of the largest Universal Immunization Programme in the world in terms of number of beneficiaries (27 million infants and 30 million pregnant women), quantities of vaccines used, geographical spread and manpower involved. [7] Though there have been some major achievements, there remain several gaps in the Indian programme, both in terms of coverage as well as quality of services. The Multi Year Strategic Plan (2005-2010) suggested priority actions in the following areas: ensuring regularity of sessions, adequate staffing, monitoring, safe injection, improved cold chain and vaccine logistics management and social mobilization. [8]

One major challenge is ensuring sustained funding for the immunization programme. Upscaling the immunization services with introduction of newer vaccines will require massive additional funding. With the traditional UIP vaccines, the average cost / child/ year is US$ 6.0, which may go up manifold to US$ 18-30 depending on the types of the newer vaccines introduced [9] [Table 3].{Table 3}

Another challenge is to maintain, expand and manage the massive cold chain system in the country. The cold chain system in India is a vast network of 27223 vaccine storage points having 199 WIC/WIF, 38393 ILRs, 28372 DFs, 41679 cold boxes and more than 1 million vaccine carriers (July 2009). [10] Every year, about 10% of electrical and 15-20% of non-electrical equipments require replacement. Moreover, almost 60% of electrical equipments in India are still CFC equipments, which must be replaced with non-CFC equipments. There is a vacancy of 509 cold chain handlers and 366 cold chain mechanics. Estimated cost of revamping the cold chain system will be US$ 68.9 million in first two years. Maintenance of equipments and expansion of cold chain points is another issue that involves large cost and organizational effort. Inclusion of newer vaccines will further enhance the requirement. Inclusion of MR vaccine in routine immunization programme will increase storage capacity requirement by 7% per Fully Immunized Child (FIC). Introduction of Pneumococcal vaccine will require increase the storage capacity by 403% per FIC, as it is presented in single dose pre-filled syringe. However, inclusion of Pentavalent vaccine from 2010, as recommended by National Technical Advisory Group on Immunization (NTAGI), if presented in 10-dose vial, may actually decrease the storage space requirement by 2% per FIC as it will replace DPT and Hep-B.

Periodic evaluation and routine reporting system reveals that there are several deficiencies in the programme implementation. Report of 'rapid household survey RCH project' revealed 72% of 244 districts surveyed in 1998-99 and 2002-03 showed a decline in full immunization rate over the years and 27% showed an increase. [8] Identified areas of concern were: low coverage pockets, poor implementation, poor monitoring, high dropouts, declining coverage in some major states, over reporting, injection safety, AEFI monitoring, re-orientation of staff, cold chain replacement plan, vacancy of staff at field level, surveillance of vaccine preventable disease, maintenance of equipments etc. There still remain unimmunized cohorts. If we consider measles coverage to be 71% and efficacy of 85%, then also actually 60.35% (71 x 0.85) child remains protected. Rest ~40% still remains vulnerable for measles [11] . Focal outbreaks of Measles are frequently being reported. While 95% of infants received at least one antigen, less than 50% children are fully immunized in India. Non-availability of trained ANM/vaccinators and supervisors is another major deficiency. Urban underserved and migratory labourers still largely remained outside the purview of RI programme planning. At different levels, data management, supervision and monitoring have major lacunae. With introduction of ADS, the immunization waste management has become a major issue for which, till date, no comprehensive policy has been formulated. An IN-CLEN study revealed 73.9% of injections given in the immunization programme were unsafe. WHO estimates that in South East Asia 31% of new HIV, 59% of hepatitis B and 92% of hepatitis C is contributed by unsafe injections. [8] Routine immunization, if unsafe, may increase the risks of acquiring those diseases manifold for millions of healthy, innocent children.

On one hand there are so many gaps and bottlenecks in the programme management, on the other hand there are numerous newer vaccines in the pipeline opening up newer opportunities to reduce child deaths. This is a peculiar juncture when we have to consider NTAGI recommendations, which explored the scope of newer vaccine inclusion. Several options have been suggested, like introduction of MR vaccine at 16-24 months with DPT booster, Rubella vaccines for adolescent girls, second opportunities of Measles in States with > 80% evaluated DPT-3 coverage, introduction of Pentavalent (DPT+HepB+HiB) from 2010 in phased manner, introduction of Pneumococcal vaccines from 2012 along with endeavor to close the gap between low and high performing units.

Developing a strong delivery system is of utmost importance to ensure availability and accessibility of quality immunization services. Keeping this in mind, a small but novel strategy has been implemented in the State of West Bengal. The State ranks among leading 5-6 states in terms of immunization coverage. But the problems identified for the country holds good for West Bengal too. The West Bengal State Immunization Support Cell (WBSISC) was established in December 2007 in the Dept. of Community Medicine, Calcutta Medical College, with support from the State Health and FW Dept. and Unicef. The project is operating in nine selected districts covering more than 40% of state's population. The objective of WBSISC is to provide techno-managerial supports in microplanning, training, cold chain and logistics management, session monitoring, data management and advocacy for quality vaccination. The Cell acts as an interface between community, peripheral units and state. Monitoring, regular feedback and data sharing are major inputs by WBSISC to different levels. Under-performing gram panchayats/ municipal wards have been identified by disintegrated data analysis and special intervention designed to cover the unreached and marginalised community. Cold chain and logistic management issues were streamlined with support from Unicef and state Health and FW department. A quick cold chain review followed by crash repair for all defective cold chain equipments to clear the backlog was another achievement. After two years of operation, some key quality indicators are showing improvement with increase in coverage. WBSISC also facilitated special programmes of Japanese encephalitis mass vaccination campaign and special vaccination campaign in AILA affected blocks. In seven riverine blocks of Sunderban areas, which were severely devastated by the cyclone 'AILA' in recent past, about 115,000 under-five children were administered Measles vaccine and Vit-A within a span of two weeks. The project has established itself as an integral part of routine immunization implementation in West Bengal. Presently the project is expanding its horizon to incorporate related child survival components like IMNCI. The faculty members of Community Medicine and post-graduate trainees are actively involved in the project. This may also be viewed as an example where people from primarily academic field are getting involved in a sustained manner in public health services.

Routine immunization programme should aim to reach every child with quality immunization services, with special focus on the vulnerable section. Positive policy support, sustained funding mechanism, strong collaboration alongwith a strong and responsive health system is necessary to attain the goal of universal coverage. Much will depend on the continued commitment of governments and the international agencies to sustain and upscale the efforts to meet the child survival goals and to meet the MDGs. Otherwise, with present trend we can only hope to achieve MDG-4 by year 2045 [6] , a bit too late!

 Acknowledgement

References