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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 34  |  Issue : 3  |  Page : 121-127

Knowledge of mothers and caretakers on adverse events following immunization in an urban community of Imphal


1 Department of Community Medicine, Zoram Medical College, Falkawn, Mizoram, India
2 Department of Community Medicine, Regional Institute of Medical Sciences, Imphal West, Manipur, India

Date of Submission20-Nov-2020
Date of Acceptance13-Jan-2021
Date of Web Publication29-Apr-2021

Correspondence Address:
Vanlalduhsaki
Department of Community Medicine, Zoram Medical College, Falkawn, Mizoram
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jms.jms_115_20

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  Abstract 


Context: Immunization is a great success in public health and has prevented a number of diseases. Although there are some adverse effects from certain vaccines, the benefits of vaccination have resulted in significant decline in infant and childhood morbidity and mortality. Parental concerns about perceived vaccine safety issues have led increasing number of parents to refuse or delay vaccination for their children. Hence, the knowledge regarding immunization in prevention of infectious disease among mothers and caretakers of under-five children is important.
Aims: We aimed to assess the knowledge of mothers/caretakers of children under 5 years of age about adverse effects following immunization.
Settings and Design: It was a cross-sectional study conducted in the urban field practice area of the Department of Community Medicine, Regional Institute of Medical Sciences, Imphal.
Subjects and Methods: House-to-house survey was carried out and data were collected using a semi-structured questionnaire among the mothers and caretakers of children under 5 years of age. A total of 400 participants were interviewed in the study.
Statistical Analysis Used: Data were entered in IBM SPSS Statistics 21 (IBM Corp. 1995, 2012) and summarized using descriptive statistics such as percentages and proportions. Chi-square test was employed to test the association between knowledge on immunization and selected variables of interest. P < 0.05 was taken as statistically significant.
Results: Out of the 400 respondents, only 23.5% had adequate knowledge regarding immunization, 19% had average knowledge, and 57.5% had poor knowledge. Mothers who were above 30 years had better knowledge than those younger (P < 0.001). The higher the education level, the better was the knowledge, and this was also significant (P < 0.001). Christians were found to have better knowledge than Hindus (P < 0.001), and working mothers had better knowledge than homemakers (P < 0.001). There was no association between type of family and knowledge. 40.3% of the respondents were aware of adverse events following immunization (AEFI), out of which 37.9% acquired it mainly from the accredited social health activists/auxiliary nurse midwives, and the most common adverse event identified was fever (87.6%). 72.2% of the respondents who had experienced an adverse event following immunization in their children reported that the event developed within 6 h.
Conclusions: Nearly one-fourth (23.5%) of the participants had good knowledge about immunization and nearly half of them were aware of AEFI. The main source of immunization and AEFI was reported to be peripheral health workers. Knowledge of the participants was significantly associated with mothers' age, educational status, and religion and employment status.

Keywords: Immunization, under-five children, vaccine


How to cite this article:
Vanlalduhsaki, Pukh R. Knowledge of mothers and caretakers on adverse events following immunization in an urban community of Imphal. J Med Soc 2020;34:121-7

How to cite this URL:
Vanlalduhsaki, Pukh R. Knowledge of mothers and caretakers on adverse events following immunization in an urban community of Imphal. J Med Soc [serial online] 2020 [cited 2021 Dec 8];34:121-7. Available from: https://www.jmedsoc.org/text.asp?2020/34/3/121/315098




  Introduction Top


Immunization has changed the course of childhood infections and has been regarded as the most cost-effective intervention for child health promotion by the WHO.[1] High immunization coverage has resulted in drastic declines in vaccine-preventable diseases, particularly in many high- and middle-income countries.[2] The National Family Health Survey (NFHS) shows a marginal improvement in the vaccination coverage of India over the years. NFHS-1 conducted in 1992–1993 reported vaccination coverage of 35.4%, which rose to 42% in NFHS-2 conducted in 1998–1999, the NFHS-3 conducted in 2005–2006 reported vaccination coverage of 43.5%, and the latest NFHS-4 conducted in 2015–2016 reported 62.0% vaccination coverage.[3],[4],[5],[6] Immunization coverage is largely dependent on knowledge and attitude of mothers, provision of services, density of health workers, and opportunity costs (such as lost earnings or time) incurred by parents.[7]

Parental concerns such as fear of potential adverse effects, refusal of recommended vaccines, concern for safety of new vaccines, misconceptions such as vaccines causing autism, or too many vaccines weaken the immune system have been reported in published research.[8] Like any medicine, vaccines carry a small risk of serious harm such as severe allergic reaction. However, experts point out that the risk of being harmed by vaccines is much lower than the risk that comes with infectious organisms.[9]

Mothers play a major role in promoting health of the children. Several misconception, ignorance, and inadequacy of knowledge in relation to immunization are prevalent among mothers. Hence, the knowledge regarding immunization in prevention of infectious disease among mothers of under-five children is important.[10] Keeping this point in view, the study was conducted to assess the knowledge of mothers and caretakers about adverse events following immunization (AEFI) in an urban community in Imphal.


  Subjects and methods Top


This study is a descriptive cross-sectional design conducted among mothers/caretakers having children under 5 years of age residing in the urban field practice area of the Department of Community Medicine, Regional Institute of Medical Sciences (RIMS), Imphal. From the family folder records maintained by the department, the total number of households in the study area was found to be 643 with a population of 3478. A total of 400 mothers/caretakers who were willing to participate and gave consent were included in the study.

Sample was calculated using the formula, n = 4PQ/L2. As there was no study on the knowledge of AEFI, a prevalence of 50% was taken with an absolute allowable error of 5% at 95% confidence interval to obtain the maximum sample size. Sampling was not done, and mothers/caretakers of children under 5 years of age were interviewed by house-to-house visit until the desired sample size was reached.

A pretested, predesigned semi-structured questionnaire was used for data collection. The questionnaire includes (A) sociodemographic profile including details of informants and children and (B) knowledge (eight items). There were nine items in the knowledge section. For each correct answer, a score of 1 was given; for two correct answers, a score of 2 was given, and for more than two correct answers, a score of 3 was given. The maximum score that could be obtained was 16 and the lowest score was 0. Based on a similar study, the score obtained by the participants was expressed in percentages and then categorized as:

  • Good: Score >60%
  • Average: Score = 36%–60%
  • Poor: Score ≤35.


After obtaining an informed consent and explaining the purpose of the study, data were collected by interviewing the mothers/caretakers of under-five children. If a mother/caretaker was unavailable on the day of data collection, a maximum of three visits were made to collect data. Those who refuse to participate and those who were unavailable after three consecutive visits were excluded from the study.

Data collected were checked for completeness and consistency. Data were entered in IBM SPSS Statistics Version 21 for Mac OS (IBM Corp, 1989, 2012. Chicago, Illinois) and summarized using descriptive statistics such as percentages and proportions. Chi-square test was employed to test the association between knowledge on immunization and selected variables of interest. P < 0.05 was taken as statistically significant.

Ethical approval was obtained from the Research Ethics Board, RIMS, Imphal, before the beginning of the study. Informed consent was obtained from the respondents. A code number was assigned and no names were taken to maintain confidentiality.


  Results Top


Four hundred mothers/caretakers residing in the urban field practice area participated in the study. Majority of the respondents (32.8%) were in the age group of 26–30 years and have one child so far (49.0%). Almost all of the respondents were currently married (98.0%). Half (50.3%) of the respondents were from Hindu faith. About one-third (32.5%) of the respondents were graduate or above. Nearly three-fourth (71.3%) of the respondents were homemakers. Majority of the respondents (72.0%) were living in joint family [Table 1].
Table 1: Sociodemographic characteristics of the respondents (n=400)

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[Table 2] shows that 36.7% of the mothers knew why children were immunized. 26.5% of the respondents knew the disease prevented by bacillus Calmette–Guerin (BCG), 32.3% knew the disease prevented by oral polio vaccine (OPV), and 11.0% knew that prevented by diphtheria–pertussis–tetanus (DPT). 36.5% knew the doses required for DPT, 36.8% knew for BCG, and 32.2% knew for measles. 35.3% knew the age/day when a child can be immunized, 65.3% knew till what age a child can be vaccinated, and 36.5% knew whether a child with mild fever can be vaccinated or not. 40.3% of the respondents understood that vaccination can cause an AEFI. 62.0% could name at least one vaccine in the National Immunization Schedule and 74.5% could name at least one vaccine that can be given at birth.
Table 2: General knowledge of respondents about immunization (n=400)

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[Table 3] shows knowledge scores obtained by the respondents. It was found that out of all the respondents, 23.5% have good knowledge, 19.0% have average knowledge, and 57.5% have poor knowledge regarding immunization of children.
Table 3: Knowledge scores of respondents regarding immunization (n=400)

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[Table 4] shows that respondents who were more than 30 years of age had better knowledge than those below of 30 years, and it was found to be statistically significant. Knowledge of the respondents increased as the educational status gets higher, and this was found to be statistically significant. Christians (60.7%) had better knowledge compared to Hindus (25.4%), and those who were working had better knowledge than those who were unemployed. It was found that there was no statistical significant association between respondents' knowledge and type of family.
Table 4: Association between knowledge on immunization and various demographic characteristics

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Out of the 161 respondents who were aware of AEFI, it was found that 37.9% of the respondents heard it mainly from the accredited social health activists/auxiliary nurse midwives (ASHAs/ANMs), 34.5% heard from doctors or nurses, 19.3% heard from their family members, 15.5% from neighbors, 8.1% from friends, and 6.8% from media. Other sources such as pictures, posters, and books comprised 6.2% [Table 5].
Table 5: Respondents' sources of knowledge about adverse events following immunization (n=161)

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The most common adverse event identified was fever (87.6%), followed by injection site swelling (25.5%); vomiting and diarrhea (20.5); other, described as inability to feed (6.8%); allergic reaction (5.6%); pain at injection site (4.3%); convulsion (1.2%); and death (1.2%) [Table 6].
Table 6: Adverse events identified or experienced by the respondents (n=161)

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[Figure 1] shows that 72.2% of the respondents who had experienced an adverse event following immunization in their children reported that the event developed within 6 h of vaccination and 3.8% reported that it developed after 24 h. 57.3% of the respondents would take their children to hospitals if adverse events develop following immunization [Table 7].
Figure 1: Time taken for adverse events to developed (n = 79)

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Table 7: Response to “what would you do if adverse events develop in your child after immunization?” (n=400)

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  Discussion Top


Childhood immunizations have a massive impact in prevention of many serious childhood infections. Despite having the world's largest immunization program, the incidence of under-five mortality in India is very high. Knowledge and attitude of parents and sociocultural factors can influence the immunization status of children.[7] This study was conducted to explore the knowledge of mothers about immunization and AEFI.

This study showed that only 36.8% of the participants knew that vaccination was meant for preventing major childhood diseases while the rest thought that it was either for treating disease or preventing all diseases. This finding was similar to Joseph et al.[7] (28%) but was contradictory to a study done by Mahalingam et al.[11] in Mangalore (69.14%) and Nnenna et al.[8] (80%). Another 38.0% of the participants could not name even one vaccine that is given in the National Immunization Schedule. Among those who could identify the vaccines, the most common vaccine known to the participants was BCG (50.3%) followed by OPV (41.3%).

Although a vast majority of the respondents agreed on the fact that immunization was important to protect their children from diseases, most of them could not even name one disease that immunization provided protection against. Similar findings were seen in other studies, where knowledge on vaccine preventable diseases was very limited.[12],[13]

When asked about the diseases prevented by vaccines, 26.5% of the respondents knew that BCG prevents tuberculosis, 32.3% knew that OPV prevents poliomyelitis, and only 11.0% knew that DPT prevents DPT. This is in contrast to a study by Sutapa et al.,[8] where around 50% of the participants knew the diseases prevented by these vaccines. A similar finding was seen by Hamid et al.[14] where 39% knew the disease prevented by OPV and 20% by that of DPT. Joseph et al.[7] found that 22% knew that OPV is given to prevent polio and 6% each knew the diseases prevented by BCG and DPT. Knowledge about diseases prevented by BCG and DPT was found to be lower than that of OPV. Inability to name or identify diseases prevented by vaccines implies that there is a need to enhance knowledge among the mothers.

Regarding the doses of vaccines, 36.5% knew the number of doses for DPT, 36.8% knew for BCG, and 32.2% knew for measles. These findings were better as compared to a study by Mandal et al.[15] where only 7.1% knew the number of doses for DPT, 24.3% knew for BCG, and 28.1% knew for measles. Similarly, Ramadan et al.[16] reported that 40.6%, 24.5%, and 24.5% knew the correct dose for BCG vaccine, DPT, and measles, respectively.

When asked when can a child start getting vaccinated, 36.5% knew that a child can start vaccination from the day of birth and 65.3% knew that they should continue vaccination till 16 years of age. This percentage is relatively low as compared to Hamid et al.[14] and Joseph et al.[7] where 100% of the respondents knew that a child can start getting vaccinated from the day of birth. Mahalingam et al.[11] reported that 91.89% of the respondents from urban and 44.44% of the respondents from rural knew the correct age to start immunization. Awodele et al.[17] found that 61.3% of their study participants knew the timing for starting immunization.

In this study, 36.5% knew that mild fever is not a contraindication for getting a child vaccinated. This finding is similar to Mahalingam et al.[11] who reported that a small proportion from the urban (20.3%) and rural (17.7%) knew that mild fever is not a contraindication for vaccination. Surprisingly, a good number of participants in this study (40.3%) had heard of AEFI and could mention at least one adverse event. This seemingly indicated the respondents to be well informed about the harmful effects of immunization.

In this study, it was found that 23.5% of the participants have good knowledge regarding immunization, 19% had average knowledge, and majority (57.5%) had poor knowledge. This finding showed that the knowledge about childhood immunization is very poor in the study population. In a similar study assessing the knowledge toward immunization of mothers of under-five children of Uttar Pradesh,[18] only 10% of the respondents had good knowledge score. This result was contradictory to another study by Mereena and Sujatha[19] that revealed more than half (61.%) of the mothers had good knowledge.

This study also found that there was a significant difference between knowledge of respondents with age. Respondents who are older (>30 years) have better knowledge than those on the younger age group (P < 0.001). A study in Hyderabad also showed the same finding.[20] However, Zahrani[21] found that younger mothers (>30 years) showed higher significant total knowledge.

When compared with the educational status of the respondents with knowledge, it was seen that knowledge regarding immunization increases significantly with the higher education (P < 0.001). In this study, about 70% of the participants had education up to secondary level, and this seemingly high education status may have influenced the knowledge of immunization. Similar findings were reported by Ankuri and Dayal[20] and Zahrani.[21] In contrast, a study in Bijapur found no association between the knowledge of mothers and their educational status.[12]

Employment status of the participants also showed a significant association with knowledge level. Those who were employed showed better knowledge (65.2%) than those unemployed (33.3%). Other studies also reported similar findings.[21],[22] With regards to religion, this study found that Christians had better knowledge than Hindu, which was also found to be significant (P < 0.001). This might be due to differences in beliefs. There was no difference in knowledge with respect to type of family (P = 0.005).

The major source from where the participants had heard of AEFI was the ASHA/ANM (37.9%), and this is in line with studies from Bijapur[23] and Lucknow,[12] where ANMs and AWW were the main sources (52.0%) of knowledge of the respondents. This reflected the importance of peripheral health-care workers in effectively bringing awareness and knowledge of immunization to the caretakers of children. 32.3% of the respondents reported that doctors and nurses were the sources of information about adverse events of immunization. The other sources included family members, neighbors, friends, and media. This finding was in contrast to a study in Libya, Egypt, where the main source of knowledge of the respondents was from TV, and Karachi, where sources of information about harmful effects of immunization were provided by friends and parents (80%).[24],[25]

Fever (87.6%) was the most common adverse event mentioned by the respondents, the finding being consistent with studies by Qidwai et al.[25] and Parrella et al.[9] where fever was reported as the most common harmful effect: 66.0% and 59.0%, respectively. It was noteworthy that 23.0% of the respondents believed that adverse event might lead to death. This reflected that the respondents had an understanding about the potential consequences of serious adverse events of immunization.

The prevalence of reported adverse events in this study is 19.8%, majority (72.2%) of which were reported to develop within 6 h of immunization. This finding is in line with observation in a study by Ekwueme[26] where most of the adverse reactions occurred within 24 h of vaccination. Another 3.8% of the participants reported the occurrence of adverse events as long as 24 h after immunization.

The actions taken by the respondents in response to the adverse events were documented. Majority of the respondents gave paracetamol, and one-fifth of the respondents informed the health-care providers of adverse event that developed in their children. Some even resorted to stop immunization temporarily and resume after the event subsided. Giving paracetamol to prevent or treat fever resulting from vaccination was also practiced by mothers in a similar study.[26]

The study participants showed a favorable attitude should their child develop an adverse event following immunization; 57.3% of them said that they would take the child to hospitals. This is a good sign, indicating that the participants have good health seeking behavior. Nnenna et al.[8] found that one-fifth of the recruited mothers would not continue immunization should their own child suffer any adverse reaction. Smailbegovic et al.[27] reported that a participant refused all the subsequent immunization after swelling developed following immunization.


  Conclusions Top


Nearly one-fourth (23.5%) of the participants had good knowledge about immunization, about one-fifth (19%) had average knowledge, and more than half (57%) had poor knowledge. The main source of immunization and AEFI was reported to be peripheral health workers. Knowledge of the participants was significantly associated with mothers' age, educational status, and religion and employment status. Overall, although a very small proportion of the mothers had adequate knowledge about immunization and the adverse events following it, it was heartening to find out that their attitude was very favorable. This implies that the mothers had awareness about immunization and its benefits though they do not know the concept too deep. Therefore, it is important to educate the mothers more about immunization and help them to understand what immunization actually does to the children.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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[PUBMED]  [Full text]  
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