Socioeconomic Factors of Full Immunisation Coverage in India


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Sharma, S. (2013) Socioeconomic Factors of Full Immunisation Coverage in India. World Journal of Vaccines, 3, 102-110. doi: 10.4236/wjv.2013.33015.

1. Introduction

The leading cause of child mortality in India is vaccine-preventable disease. The vaccine not only protects the children from potentially serious illness but also interrupts the diseases transmission in a community. However, in developing countries including India, a large proportion of children are either not immunised at all or partially immunised, resulting in higher infant and child mortality. The UN Millennium Declaration had outlined the reduction of under five mortality as one of the eighth goals with proportion of 1-year-old children immunised against measles as one of the monitoring indicators (UN 2003) [1]. The basic childhood vaccinations have been advocated as the most important medical intervention in preventing childhood morbidity and mortality.

The World Health Organization launched the Expanded Immunisation Programme in 1974 to prevent six major preventable childhood diseases namely, the measles, tuberculosis, pertussis (whooping cough), diphtheria, tetanus and poliomyelitis [2]. Under the EIP, children receive one dose of BCG for protection against tuberculosis, three doses of the triple vaccine DPT (diphtheria, pertussis and tetanus), three doses of either IPV (inject able) or OPV (oral) for poliomyelitis protection and one dose of the measles vaccine by their first birthday. These combinations are also known as basic childhood immunisation or full immunisation in various countries and used interchangeably [3].

Immunisation forms a critical component of primary health care and ensures a nation’s health security. Basic childhood immunisation services are part of the essential health services in India and accorded top priority in its health delivery system. The first official childhood vaccination policy was formally announced in 1978 at Alma Ata, Kazakhstan [4]. In 1985, India launched the Universal Immunization Programme (UIP) to protect all infants (0 - 12 months) against six serious but preventable diseases—tuberculosis, diphtheria, pertussis, tetanus, poliomyelitis, and measles—by fully vaccinating at least 85 percent of all one-year-olds [5].

In 1992, the Child Survival and Safe Motherhood Programme (CSSM) was launched to reduce infant mortality rate (IMR) to 50, under-five mortality to 70, maternal mortality ratio (MMR) to 200, and crude birth rate CBR to 9. According to the National Family Health Survey (NFHS) II [6], only 35.4 percent of children were fully immunised in 1992-1993 [7]. Later, the UIP and the CSSM became an important part of the Reproductive and Child Health Programme (RCH). The goals of the RCH Programme are to reduce infant and maternal mortality rate and to simultaneously increase the contraceptive prevalence rate in India. But non-immunisation prevails despite many such initiatives—only 43.6 percent of the population was fully immunised in 2005-2006 [8].

The Ministry of Health and Family Welfare (MoHFW) revised the target and strategies of the UIP in the National Population Policy, 2000 (NPP) and in the National Rural Health Mission, 2005 (NRHM) (Kumar & Mohanty) [9,10]. These brought hope that India would reach its Millennium Development Goals (MDGs) and achieve the target of full immunisation.

A Standard Immunization Schedule (SIS) was developed for the child immunisation programme. It specifies the age at which each vaccine is to be administered, the number of doses to be given, and the route of vaccination (intramuscular, oral, or subcutaneous). Routine vaccinations received by infants and children are usually recorded on a vaccination card issued for each child.

Despite the importance of basic childhood immunisation, its coverage extends to only a minority of the children in the country, varies widely across states, and differs by economic and social status of household. For example, in 2005-2006, 24.4 percent of children aged 12 - 23 months in the poorest quintile were fully immunised but 71 percent among the wealthiest quintile (Kumar & Mohanty) [10].

The Coverage Evaluation Survey 2009 (CES) evaluated 61 percent of full immunisation coverage in India—67.4 percent in urban areas and 58.5 percent in rural areas. The coverage of Universal Immunisation Programme UIM in India is over 70 percent in only 11 states, 50 - 70 percent in 13 states, and below 50 percent in the remaining states (the most populous states of the country) [11]. Most health indicators are low in states where immunisation coverage is low. Although the NRHM focuses strongly in those states, the gap between target and achievement of child immunisation is large. The coverage of full immunisation had increased by 4 percent during 1992 to 1998 and 5 percent during 1998 to 2005. Full immunisation has declined in some states.

In India, childhood immunisation has been an important part of maternal and child health (MCH) services since independence. The Bacille Calmette Guerin (BCG) vaccine started in 1948. Between 1969 and 1985, Expanded Immunisation Programme EPI was adopted and vaccines for DPT, measles, and other childhood illnesses were added (Kanitkar 1979; Basu 1985) [12,13]. In 1984, UNICEF included six vaccine-preventable diseases. In 1985-1986, the Government of India (GoI) launched the UIP to vaccinate at least 85 percent of all infants by 1990. Children are considered fully vaccinated if they have received by their first birthday one dose of BCG protection against tuberculosis, three doses of DPT, three doses of either IPV (injectable) or the more commonly used OPV (oral) for poliomyelitis protection, and one dose of measles vaccine.

The study aims to explore and analyse the impact of socioeconomic factors of the coverage of full immunisation in different states of India. It also examines the levels, trends, and changes in full immunisation.

2. Data and Methodology

The present paper uses the state-wise data from three successive rounds of National Family Health Surveys (NFHS) conducted during 1992-2005. The first round of NFHS was conducted in 1992-1993, the second round in 1998-1999, and the third round in 2005-2006 [6-8]. The NFHS is a large-scale, multi-round survey conducted in a representative sample of households throughout India. These population based surveys are similar to other Demographic and Health Surveys (DHS) and provide state and national information for India on fertility, infant and child mortality, family planning practices, MCH, RCH, nutrition, anaemia, and the utilisation and quality of health and family planning services. Each successive round of the NFHS aims to provide 1) the MoHFW and other agencies data essential to health and family welfare policy and programmes and 2) information on important emerging health and family welfare issues.

All the rounds of the survey are nationally representative and cover more than 99 percent of the country’s population. The coverage of topics and geographical areas is improved between rounds. However, for vaccination coverage, the information collected through all the successive rounds of NFHS are on overall childhood vaccination for the surviving child or born in the reference period. The analysis uses data pooled from three periods (1992-1993, 1998-1999, and 2005-2006) to attain an adequate sample size and to understand the effect of time on immunisation coverage.

The dependent variable in the study is the percentage of full immunisation and the independent variables are age of the mother, sex of the child, birth order, religion, caste of household, education status, mass media, place of residence, standard of living index (SLI), working status of mother, availability of health card, antenatal care (ANC) visit, and mother’s age. Data on immunisation are based on the vaccination card for each living child or—if the card is not available—on the mother’s report. This analysis takes the 12 - 23 month age group because both international and GoI guidelines specify that children should be fully immunised by the time they complete their first year of life [14].

The objective of the study is carried out by using the multinomial logistic regression model, as the dependent variable “full immunization” is qualitative in nature. It indicates whether a child has been administered all the six vaccinations or not, that is, 1 if fully immunised and 0 if not fully immunised. The paper tries to predict the probabilities of the different possible outcomes of full immunisation, which is a continuously categorically distributed dependent variable, given a set of independent variables. The predictive values are calculated from logistic regressions that simultaneously incorporate all the selected predictor variables. Also, while calculating the predictive values for a variable, all the other variables are controlled by setting them to their mean values in the underlying regression.

3. Results

3.1. Increasing Trends in Immunisation Coverage in India and States

The percentage of full immunisation has increased in five states (Haryana Kerala, Orissa, Uttar Pradesh, and West Bengal) over the three rounds of National Family Health Surveys (Table 1 & Figure 1). The highest percentage change is in Kerala (2005-2006), and the highest positive percentage change is in West Bengal, which shows that full immunisation in West Bengal is growing rapidly there.

3.2. Oscillating Trends in Immunisation Coverage in India and States

Except Gujarat, all states show an oscillating trend in full immunisation (Table 2). The percentage of full immunisation in Andhra Pradesh, Himachal Pradesh, Karnataka, Maharashtra, and Punjab increased in 1998-1999 and decreased in 2005-2006, but in Assam, Bihar, Jammu and Kashmir, Madhya Pradesh, and Rajasthan, it decreased in 1998-1999 and increased in 2005-2006. Further, the changes in full immunisation were positive for all states except Gujarat, Maharashtra, and Punjab.

3.3. Socioeconomic and Demographic Differentials of Child Immunisation

There is a wide variation in immunisation coverage in terms of socioeconomic and demographic factors and gender. These determinants have a positive association with full childhood immunisation. Mothers in the 25 - 35 age group are the most immunised of all age groups of mothers in all the three rounds of the NFHS (Table 3) [6-8]. More females than males are immunised. In 2005-2006, 61.1 percent of mothers in the 25 - 35 age group had a high standard of living; 27.7 percent had a medium standard of living; and 42.2 percent had a low standard of living. Many studies indicate that wealth and regional inequalities in India are correlated with immunisation overall in a non-linear fashion. The place of residence also has variation in full immunisation. Immunisation coverage is higher in urban areas as compared to rural places [14].

3.4. Dropout Level of Immunisation

The trend of dropout for the BCG-measles, DPT1-DPT-3, and Polio 1-Polio 3 vaccines in Assam, Bihar, Haryana Jammu & Kashmir, Madhya Pradesh, Orissa, Rajasthan, Utter Pradesh and West Bengal oscillated over the period (Table 4). The coverage in dropouts for different vaccines increased at different times in Andhra Pradesh, Gujarat, Himachal Pradesh, Karnataka, Kerala, Maharashtra, Punjab, Tamil Nadu, Delhi, and Uttarakhand.

3.5. Factors of Full Immunisation

The study uses multivariate analysis to understand the socioeconomic and demographic factors of immunisation coverage. We control for significant covariates in the model, such as sex of child, woman’s parity, age, mo-

Table 1. States with increasing trends of full immunization.

Figure 1. States with increasing trends of full immunisation.

Table 2. States with oscillating full immunisation trends.

ther’s education, place of residence, SLI, caste, and religion, exposure to mass media, working status, and possession of health card. The study excludes mother’s antenatal care visit from the multivariate analysis because of the multi-collinearity problem. The multiple classification application (MCA) is used to present the multinomial logit regression results in terms of the predicted percentage to avoid complexity in interpretation.

Table 5 presents the results of the multivariate analysis. Many researchers (such as Nilanjan Patra) [15,16], affirm the greater likelihood of immunisation of children in urban areas but the disparity is not statistically significant after controlling for other variables at their mean. Age plays an important role in women’s utilisation of medical services. Maternal age may sometimes serve as a proxy for the accumulated knowledge of healthcare services that women have, which may positively influence the acceptance of full immunisation of children (Rahman & Nasrin 2010) [17]. The age of mothers remained a significant factor for having a child fully immunised, after holding other variables at their mean (predictive percentages are 38.0, 46.0*** and 40.0** respectively).

Although vaccines for childhood immunisation are free in India, boys are significantly more likely to be fully immunised than girls (predictive percentage 43.0 and 40.3*** respectively). However, the gender gap fell to 5 percent in NFHS-III from 10 percent in the previous two rounds (Nilanjan Patra) [15,16]. There were a higher proportion of boys (53 percent) than girls surveyed in

Table 3. Socioeconomic and demographic differentials of child immunisation during the three rounds of the NF-HS (%).

NFHS-3. The complete vaccination rate was 45.3 percent for boys and 41.5 percent for girls. This gender imbalance existed irrespective of the method of determination of vaccination status (Joseph Mathew) [18]. Thus, there is a consistent positive relationship between immunisation coverage and the sex of child.

The different likelihoods of immunisation for different birth orders are also strongly significant. The likelihood of vaccination decreases with the increase in birth order. There is an inverse relationship between immunisation coverage and increased birth order of children. Children are more likely to be immunised with a low number of birth order (predictive percentage 48.5, 46.8** and 36.1*** respectively), possibly because more children may constrain resources and negatively affect healthcare utilisation (Rahman & Nasrin 2010) [15].

There is a strong positive relationship between mother’s education and children’s immunisation coverage. Mothers who had primary, secondary, and higher education were more likely to fully immunise their children than those with no education [14]. Religion and caste significantly affect full immunisation. Hindu children are more likely to be immunised than children from other religions, while holding the other values at their mean (predictive percentage are 41.0 and 40.0 respectively).

The working status of women and media exposure are significantly associated with the acceptance of full immunisation coverage (predictive values are 39.2 and 41.7 respectively). Working women are usually more educated and aware of their family members’ health and, therefore, know the harmful effects of non-immunisation. People with a high standard of living are likely to be more immunised than others [19].

In sum, the standard of living, media exposure, and higher level of education of mothers are found important factors affecting full immunisation coverage throughout the period [19].

4. Discussion

The coverage of immunisation has progressed slowly and is far from the GoI’s goals under different programmes. Despite its longstanding effort to achieve universal immunisation, over half the children had not been administered all the doses of recommended vaccines and the pattern remained similar over the period. The coverage of childhood immunisation varied across states, and a North-South divide is clearly visible. Despite the low coverage, the rate of increase is higher among economically backward states of the country than among economically better states, possibly because of lower level at the starting point among economically backward states.

The coverage of BCG, three doses of DPT, and measles vaccine is lower than that of polio vaccine in India and the states, and there has been very little improvement over time. The coverage of BCG, a primary vaccine, remained very low in India over the periods, and may hinder the goal of universal immunisation. The coverage of polio vaccines is higher and has increased consistently. The dropout rate between BCG-measles remains very

Table 4. Dropouts level of immunisation by vaccines in India and states (1992-1993 to 2005-2006).

high. The measles vaccination is very poorly addressed in India; full immunisation is low. The dropout rate between three doses of DPT also increased during the 14 years.

Full immunisation coverage largely varied by mother’s educational attainment and exposure to mass media. Immunisation coverage is about twice as high among mothers with more than 10 years of schooling as among those with five or fewer years of schooling. The results for exposure to mass media are similar, and bear out other studies documenting the link between maternal education and child health (Desai and Alva 1998; Streatfield et al. 1990) and between maternal exposure to mass media and child health (Rahman 2007) [20-22]. Immunisation coverage varied substantially with the economic status of households, in line with other studies that corroborated the link between socioeconomic status and immunisation coverage and other health care services across developing countries (Gwatkin et al. 2000; Kunst & Houweling 2001; Mohanty & Pathak 2009; Pande & Yazbeck 2003) [ 10,23-25]. The coverage of full immunisation among children born to religions other than Hinduism is lower probably because their parents believe that vaccination is harmful.

Besides socioeconomic factors, the possession of a health card is strongly associated with the coverage of full immunisation in India and the states. In standard practice, immunisation rates from large-scale demographic health surveys are derived from the information recorded on health cards where these cards are available (Boerma & Bicego 1994; Brown et al. 2002) and such estimates are found to be of good quality (Langsten & Hill 1998) [26-28]. However, when there are no health cards, mothers’ reports are associated with errors of overestimation, measles vaccine in particular (Hawe et al. 1991; McKinney et al. 1991) [29,30], and underestimation of overall immunisation in general (Christopher et al. 2003; Gareaballah & Loevinsohn 1989; Suarez et al. 1997; Valadez & Weld 1991) [31-34]; our results accord with this underestimation. The coverage of full immunisation based on health cards is consistently increasing over time in India and the states, but progress is either sluggish or stagnant among children without health cards. A plausible reason for this slow progress may be reporting bias; it needs to be explored further.

5. Conclusion

Despite the increase in healthcare services and the launch of various programmes in India, full immunisation coverage for children younger than five is currently highly

Table 5. Results of multinomial logit regression (predicted %): full immunisation coverage in India and selected states, 1992-2005.

inadequate. The gap between the target of child immunisation and the achievement is large. The trends in full immunisation have increased slightly over time than other RCH indicators in India. Moreover, full immunisation in India is only increased with very low level.

The study attempts to understand the trends and changes in the coverage of full immunisation and their socioeconomic factors. Based on trend analysis, states such as Haryana, Kerala, Orissa, Uttar Pradesh, and West Bengal show increasing trends of full immunisation over the three NFHS rounds. However, the percentage for full immunisation is highest in West Bengal. The full immunisation coverage rate declined in economically progressive Gujarat. The trends of full immunisation oscillated in the other states.

Socioeconomic determinants have a positive association with full childhood immunisation. The imbalances between boys vs girls, rural vs urban, scheduled caste/tribe vs others, and illiterate vs literate parents; for complete vaccination coverage as well as non-vaccinated infants were similar in the BIMARU states as all over India. Thus, the coverage of all basic childhood immunisation in the country still had never reached up to the mark; there is wide variation in coverage of immunisation among states of India.

• 5.1. Key Findings

• Boys are still significantly more likely to be fully immunised than girl children.

• There is an inverse relationship between immunisation coverage and increased birth order of children. Children are more likely to be immunised with low number of birth order.

• It have also been that observed there is a strong positive relationship between mother’s education and children’s immunisation coverage.

• The respondents who had higher levels of education, mothers who engaged in jobs and those having mass media access, were more likely to fully immunise their children.

• There is a significant relation between standard of living and full immunisation of children. People belong to high standard of living are more likely to immunise their children.

5.2. Suggestions and Recommendations

In order to achieve 100 percent full immunisation:

• Appropriate education should be provided to the women form the rural area, which will enhance their knowledge and health seeking behaviour for their children at the perfect age.

• Government should increase the availability of healthcare centres for immunisation vaccine.

• Mass media promotion programme should be undertaken.

• Women should be encouraged to avail ANC services.

• Education status of rural women should be increased, to encourage them to seek immunisation and other health care services

Conflicts of Interest

The authors declare no conflicts of interest.


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