Objective
The study aimed to determine the factors associated with parents’ decision of their child participation in a school-based typhoid vaccination program in Lalitpur District, Nepal.
Methods
Following a typhoid vaccination campaign in 2012, a household cross-sectional survey, following a two stage stratified, cluster-sampling strategy. The strata were based on type of school (public/private) and geographic location (urban/rural). Data were collected through a structured questionnaire ensuring standard quality practices. Logistic regression analysis was used to assess the effect of socio-economic and behavioral characteristics with participation in the school-based vaccination campaign. The study was approved by Institutional Review Board of International Vaccine Institute and Nepal Health Research Council.
Results
A total of 1,248 interviews were conducted with parents of children from 42 schools with a response rate of 85 percent. The participation in the vaccination campaign was statistically significantly associated with confidence on the organization conducting the vaccination campaign (OR=0.2; 95% CI: 0.1 - 0.7) knowledge of typhoid vaccine preventing the disease (OR=9; 95% CI: 4.2 - 19.7), concern of vaccine related adverse events following vaccination (OR=0.3; 95% CI: 0.2 - 0.6), information on typhoid vaccination campaign (OR=3; 95% CI: 1.9 - 5.0), and receipt of a permission slip for the child to receive the vaccine from school (OR=2; 95% CI: 1.3 - 3.2).
Discussion
Our results suggest that participation in a school-based vaccination program is associated with knowledge of disease specific vaccine on safety and effectiveness, if the parent was reached effectively by the vaccination teams through information material, and if the population have confidence in the organization that is conducting the vaccination campaign. Our results are consistent with the findings from vaccination programs on typhoid and other vaccines, globally and in Asia on a perceived risk of the disease, knowledge and confidence over vaccines and a set of communication channels by which parents are informed about the vaccine benefits to the target population.
Salmonella entericserovars are associated with three distinct clinical syndromes: a) enteric fever results from infection by the typhoidal Salmonellas (Salmonella Typhi and Salmonella Paratyphi A, B, and C; b) non-typhoidal Salmonella gastroenteritis; and c) non-typhoidal Salmonella bacteremia (invasive disease caused by non-typhoidal Salmonellae) [1]. Enteric Fever (EF) is an acute systemic infection, representing two similar clinical illnesses, typhoid and paratyphoid fever, caused by different serotypes of the bacteria Salmonella enterica, serotypes Typhi (S. Typhi) and Paratyphi (S. Paratyphi A, B, and C), respectively. Combined morbidity and mortality caused by infections of Salmonella entericserovars is considerable since this group of bacterial pathogens are responsible for a global toll of approximately one million deaths annually, making them as one of the leading causes of mortality worldwide [2].
The World Health Organization (WHO) recommends targeted typhoid fever vaccination in typhoid endemic regions through school-based and high-risk vaccination campaigns [3]. Typhoid polysaccharide vaccines are licensed for use in children older than 2 years, limiting their use in routine immunization programs such as Expanded Program on Immunization (EPI) in typhoid endemic countries. School-based programs are considered an effective strategy to attain high vaccination coverage rates. The key issue in the feasibility and value of conducting a school-based typhoid vaccination program is the additional logistical support required to reach all eligible children. Parental refusal to accept their child’s participation in a program affects vaccination coverage and in turn increases the cost per vaccine dose [4]. The influential reasons for parental acceptance and refusal in vaccination programs vary by region and country: from perceived vaccine efficacy, to perceived need for a vaccine, to perceived adverse events associated with vaccines and their cost. Socio-demographic factors also affect vaccination participation (e.g., a lack of risk perception for contracting the disease among the population with a high Socioeconomic Status (SES)) [5-8]. However, all of such concerns can be addressed through provision of adequate information on the disease, the vaccination program, and the organization leading the effort [9].
Typhoid fever is very common in Nepal, and has had repeated outbreaks in the past. Multi-drug resistance Salmonella typhi and paratyphi are the most common infectious organism isolated from the blood stream of children [10]. Drinking water in Kathmandu valley is highly contaminated with Salmonella Typhi and Paratyphi [11]. Approximately 9000 cases of S. Typhi were isolated between 1993 and 2003 from only one hospital, highlighting the magnitude and burden of enteric infection in the valley. Currently there are two vaccine licensed for marketing globally. The injectable, single dose Vi polysaccharide vaccine, and live attenuated oral Ty21a vaccine that has a four dose schedule. Both vaccines are licensed for two years and older population. The duration of protection for injectable vaccine is three to seven years, whereas the oral vaccine is five to seven years [12]. The Vi-based Vaccines for Asia Initiative (ViVA) of the International Vaccine Institute (IVI) aimed to provide evidence for the feasibility and effectiveness of school-based typhoid vaccination to reduce the burden of typhoid fever in school-aged children (5-15 years). Children in this age group have high rates of typhoid fever. In addition, resistance to commonly used antibiotics continues to increase in south Asia and in Nepal [13]. The Vi vaccine pilot introduction project was developed with support from the IVI and implemented by the District Public Health Office of Lalitpur District, Kathmandu Valley, Nepal with a help of a non-governmental organization, MITRA Samaj between 2010 and 2013. A single dose of injectable typhoid polysaccharide vaccine was given through a mass vaccination campaign to the children attending the schools of Lalitpur District, Nepal. Coverage records showed that nearly 35% of eligible students did not receive the vaccine through the school-based program. Initial reasons for parental refusal during social mobilization campaign and vaccination monitoring indicated that there was a fear of the vaccination due to rumors and prior experiences with other prevention/treatment campaigns. Along with skepticism towards the general safety of the vaccine, prior information on experiences with the vaccine added to the concerns of the parents [14].
We collected information following the vaccination campaign in order to understand the reasons that either engaged or hindered parents’ participation in typhoid vaccination campaign. Specifically, the study aimed to identify factors that influenced parents’ decision to allow their child/children participation in the school-based mass vaccination.
The data analysis involved descriptive statistics for sample demographics using Stata version 9.0. Pearson’s chi square test was performed for categorical variables, along with t-tests and ANOVA for continuous variables to test statistically significant difference between groups. Based on the results from the descriptive analyses, adjusted analyses were performed to determine factors affecting vaccination participation using logistic regression analysis.
The research was approved by the Institutional Review Board (IRB) of the International Vaccine Institute, the Nepal Health Research Council and the Ministry of Health and Population of the Government of Nepal.
Vaccination Coverage | Number of participants | Total | ||||||
Low | Medium | High | ||||||
Area | n | % | n | % | n | % | n | % |
LSMC | 71 | 7.36 | 741 | 76.79 | 153 | 15.85 | 965 | 77.3 |
VDC | 46 | 16.25 | 154 | 54.42 | 83 | 29.33 | 283 | 22.7 |
Total | 117 | 9.38 | 895 | 71.71 | 236 | 18.91 | 1248 |
Variable | Received vaccine | Did not receive vaccine | Odd Ratio | 95% CI for Odds Ratio | ||
Yes (893) | No (356) | |||||
N | % | n | % | |||
School attendance | ||||||
No | 136 | 15.3 | 52 | 14.7 | REF | |
Yes | 755 | 84.7 | 302 | 85.3 | 1.1 | 0.76 - 1.59 |
Education Level | ||||||
Primary | 94 | 12.5 | 25 | 8.2 | REF | |
Lower Secondary | 72 | 9.5 | 22 | 7.2 | 0.92 | 0.48 - 1.78 |
Secondary | 158 | 21.0 | 64 | 21.1 | 0.69 | 0.4 - 1.19 |
Higher Secondary | 166 | 22.0 | 74 | 24.3 | 0.6 | 0.34 - 1.05 |
Bachelor | 185 | 24.5 | 87 | 28.6 | 0.56 | 0.32 - 0.98 |
Masters | 79 | 10.5 | 32 | 10.5 | 0.61 | 0.32 - 1.17 |
Household member (Mean/SD) | 5 | 4.75 | 1.06 | 0.99 - 1.13 | ||
Monthly Household Income (Mean/SD) | 25308 | 30135 | 1 | 1 | ||
Monthly Household Expenditure | 1.4 | 0.69 - 2.82 |
Table 2: Distribution and association of respondents’ socio-demographic factors with participation in the typhoid vaccination campaign in Kathmandu, Nepal.
Variable | Received vaccine | Did not receive vaccine | Odd Ratio | 95% CI for Odds Ratio | ||
Yes (893) | No (356) | |||||
How serious of a disease is typhoid fever? | ||||||
Not serious | 121 | 13.7 | 72 | 20.6 | REF | |
Serious | 644 | 73.0 | 249 | 71.1 | 1.45 | 1.04 - 2.02 |
Very serious | 117 | 13.3 | 29 | 8.3 | 2.31 | 1.39 - 3.83 |
Bearing the cost | ||||||
No | 183 | 21.7 | 96 | 29.5 | REF | |
Yes | 660 | 78.3 | 229 | 70.5 | 1.4 | 1.04 - 1.89 |
Do you think typhoid can be prevented by a vaccine? | ||||||
No | 12 | 1.5 | 26 | 7.4 | REF | |
Yes | 809 | 98.5 | 223 | 63.9 | 7.8 | 3.84 - 15.81 |
Do you think all members from your family should be vaccinated for typhoid? | ||||||
No | 41 | 5.0 | 57 | 19.5 | REF | |
Yes | 779 | 95.0 | 236 | 80.5 | 4.4 | 2.86 - 6.78 |
Variable | Received vaccine | Did not receive vaccine | Odd Ratio | 95% CI for Odds Ratio | ||
Yes (893) | No (356) | |||||
Typhoid vaccination campaign knowledge | ||||||
No | 114 | 12.8 | 115 | 32.4 | REF | |
Yes | 779 | 87.2 | 240 | 67.6 | 3.39 | 2.5 - 4.58 |
Typhoid Knowledge source - Child | ||||||
No | 208 | 23.3 | 150 | 42.1 | REF | |
Yes | 685 | 76.7 | 206 | 57.9 | 2.43 | 1.86 - 3.17 |
Typhoid Knowledge source - Letter from school | ||||||
No | 456 | 51.1 | 234 | 65.7 | REF | |
Yes | 437 | 48.9 | 122 | 34.3 | 1.82 | 1.41 - 2.36 |
Typhoid Knowledge source - Teacher | ||||||
No | 815 | 91.3 | 344 | 96.6 | REF | |
Yes | 78 | 8.7 | 12 | 3.4 | 2.48 | 1.32 - 4.65 |
Children could not receive vaccine (Mean/SD) | 0.2 | 1.33 | 0.1 | 0.08 - 0.13 | ||
Concern of vaccine adverse effect | ||||||
No | 771 | 89.2 | 207 | 71.6 | REF | |
Yes | 93 | 10.8 | 82 | 28.4 | 0.3 | 0.21-0.42 |
Discussed AE concern with health care provider | ||||||
No | 857 | 96.0 | 354 | 99.4 | REF | |
Yes | 36 | 4.0 | 2 | 0.6 | 6.76 | 1.61-28.35 |
Discussed AE concern with teacher | ||||||
No | 862 | 96.5 | 352 | 98.9 | REF | |
Yes | 31 | 3.5 | 4 | 1.1 | 2.96 | 1.03-8.52 |
Table 4: Distribution and independent association of campaign knowledge with participation in the typhoid vaccination campaign in Kathmandu, Nepal.
Variable | Received vaccine | Did not receive vaccine | Odds Ratio | 95% CI for Odds Ratio | ||
Yes (893) | No (356) | |||||
Did you receive any information about the typhoid vaccination program from the school? | ||||||
No | 79 | 9.3 | 80 | 27.8 | REF | |
Yes | 775 | 90.7 | 208 | 72.2 | 3.98 | 2.8 - 5.68 |
What information did you receive? Vaccinate your children | ||||||
No | 468 | 52.4 | 262 | 73.6 | REF | |
Yes | 425 | 47.6 | 94 | 26.4 | 2.46 | 1.87 - 3.23 |
Did you get a permission letter from school that was asking your permission for vaccinate your child? | ||||||
No | 120 | 14.4 | 68 | 25.0 | REF | |
Yes | 716 | 85.6 | 204 | 75.0 | 1.93 | 1.37 - 2.71 |
Did you have any reservations in signing the form requesting your permission for vaccinating? | ||||||
No | 579 | 83.5 | 146 | 76.0 | REF | |
Yes | 114 | 16.5 | 46 | 24.0 | 0.61 | 0.41 - 0.91 |
Did you/other responsible person sign the form? | ||||||
No | 17 | 2.4 | 17 | 8.4 | REF | |
Yes | 702 | 97.6 | 186 | 91.6 | 4.51 | 2.2 - 9.25 |
Did you think the information in the permission form was too technical? | ||||||
No | 438 | 74.2 | 126 | 85.7 | REF | |
Yes | 152 | 25.8 | 21 | 14.3 | 2.28 | 1.36-3.82 |
We distributed a brochure that was given to the child to bring it to you. Did you receive it? | ||||||
No | 364 | 44.7 | 206 | 68.7 | REF | |
Yes | 451 | 55.3 | 94 | 31.3 | 2.82 | 2.12-3.75 |
Did you think the brochure had enough information required making a decision of vaccinating your child? | ||||||
No | 8 | 3.0 | 9 | 19.6 | REF | |
Yes | 256 | 97.0 | 37 | 80.4 | 9.16 | 3.19-26.3 |
Able to recall any information from the brochure? | ||||||
No | 739 | 82.8 | 330 | 92.7 | REF | |
Yes | 154 | 17.2 | 26 | 7.3 | 2.75 | 1.77-4.26 |
Able to recall: Typhoid is dangerous | ||||||
No | 798 | 89.4 | 337 | 94.7 | REF | |
Yes | 95 | 10.6 | 19 | 5.3 | 2.16 | 1.28-3.65 |
Saw the campaign banner outside the school? | ||||||
No | 685 | 76.8 | 306 | 90.3 | REF | |
Yes | 190 | 21.3 | 29 | 8.6 | 2.72 | 1.79-4.13 |
Did not accompany the child | 17 | 1.9 | 4 | 1.2 | 1.98 | 0.65-5.99 |
Saw the campaign poster in the school? | ||||||
No | 719 | 80.6 | 298 | 87.9 | REF | |
Yes | 152 | 17.0 | 32 | 9.4 | 1.92 | 1.27-2.89 |
Did not accompany the child | 21 | 2.4 | 9 | 2.7 | 1.05 | 0.47-2.33 |
Did you hear about typhoid on the radio during the vaccination program? | ||||||
No | 737 | 82.5 | 315 | 89.2 | REF | |
Yes | 156 | 17.5 | 38 | 10.8 | 1.7 | 1.16-2.49 |
Did you think the public service message on radio was informative? | ||||||
No | 7 | 8.4 | 2 | 11.8 | REF | |
Yes | 76 | 91.6 | 15 | 88.2 | 1.33 | 0.24-7.34 |
Table 5: Distribution and independent association of the consent process, project communication and social mobilization with participation in the typhoid vaccination campaign in Kathmandu, Nepal.
Variable | Received vaccine | Did not receive vaccine | Odd Ratio | 95% CI for Odds Ratio | ||
Did your child’s school encourage you to vaccinate your child? | ||||||
No | 218 | 27.2 | 123 | 53.9 | REF | |
Yes | 584 | 72.8 | 105 | 46.1 | 3.24 | 2.38 - 4.41 |
Do you think the fact that this vaccination program was being conducted at the school influenced your decision of participation in the campaign? | ||||||
No | 268 | 32.7 | 174 | 69.3 | REF | |
Yes | 552 | 67.3 | 77 | 30.7 | 4.83 | 3.54 - 6.58 |
Do you think the fact that this vaccine was given free influenced your decision of vaccinating/not vaccinating? | ||||||
No | 623 | 75.7 | 188 | 75.2 | REF | |
Yes | 200 | 24.3 | 62 | 24.8 | 0.94 | 0.67 - 1.32 |
Do you think schools are an acceptable place for vaccinating children? | ||||||
No | 49 | 5.6 | 55 | 17.6 | REF | |
Yes | 825 | 94.4 | 258 | 82.4 | 3.49 | 2.3 - 5.28 |
Are you satisfied with the way the vaccination program was conducted? | ||||||
Not satisfied | 7 | 0.8 | 27 | 17.6 | REF | |
Satisfied | 739 | 88.7 | 125 | 81.7 | 23.17 | 9.85 - 54.5 |
Very Satisfied | 87 | 10.4 | 1 | 0.7 | 319.5 | 37.6 - 2718.1 |
The vaccine should be given at a health clinic? | ||||||
Agree | 346 | 39.4 | 148 | 44.2 | REF | |
Disagree | 533 | 60.6 | 187 | 55.8 | 1.25 | 0.97 - 1.62 |
The child will miss a school day in case the vaccination | ||||||
Agree | 530 | 60.2 | 223 | 66.6 | REF | |
Disagree | 350 | 39.8 | 112 | 33.4 | 1.24 | 0.95 - 1.62 |
I want to be present while my child receives the vaccine | ||||||
Agree | 656 | 74.6 | 282 | 81.7 | REF | |
Disagree | 223 | 25.4 | 63 | 18.3 | 1.61 | 1.18 - 2.21 |
In case something happens to my child, school is not prepared to handle the situation | ||||||
Agree | 175 | 31.1 | 51 | 18.3 | REF | |
Disagree | 563 | 100.0 | 227 | 81.7 | 0.69 | 0.49 - 0.98 |
We are not sure of the competitiveness of the staff conducting the vaccination. | ||||||
Agree | 251 | 31.3 | 101 | 34.8 | REF | |
Disagree | 551 | 68.7 | 189 | 65.2 | 1.33 | 0.99 - 1.78 |
The organization conducting the vaccination campaign is important | ||||||
Agree | 862 | 98.4 | 317 | 93.0 | REF | |
Disagree | 14 | 1.6 | 24 | 7.0 | 0.22 | 0.11 - 0.44 |
Household Income (UNIT) | ||
< 17,000 | 1 | |
17,001 - 30,000 | 1.1 | 0.7 - 1.8 |
> 30,000 | 1.7 | 0.4 - 1.1 |
Can typhoid be prevented with a vaccine? | ||
No | 1 | |
Yes | 9.1 | 4.2 - 19.7 |
Concern of Adverse Event | ||
No | 1 | |
Yes | 0.3 | 0.2 - 0.6 |
Information on Typhoid campaign | ||
No | 1 | |
Yes | 3 | 1.9 - 5.0 |
Permission Slip | ||
No | 1 | |
Yes | 2 | 1.3 - 3.2 |
Organizational Confidence | ||
Agree | 1 | |
Disagree | 0.2 | 0.1 - 0.7 |
Table 7: Adjusted effect of factors affecting participation in the typhoid vaccination campaign in Kathmandu, Nepal.
Our results provide important insights into factors associated with participation in a school-based, typhoid vaccination program in the Lalitpur. We also assessed how social mobilization and the dissemination of communication material and activities affected participation. We explored the importance of vaccination campaign logistics, such as the consenting process as affecting participation in the vaccination program with a vaccine that is not given in routine immunization program in Nepal. Our results suggest that participation in a vaccination program is built over a long duration through parental education about the benefits of vaccines, the reputation of the organization in their handling previous community or school-based programs, and regular and proper communication with the parents. Our results are consistent with the findings globally and in Asia on a perceived risk of the disease, knowledge and confidence over the vaccines, and a communication channel by which parents are informed about the vaccine benefits to the children and the population in general [18-20].
The routine immunization coverage for Nepal is one of the highest in the in South Asia (coverage rate of 90% for Diphtheria, Tetanus and Polio (DTP3)) . The DTP3 coverage has improved from 72% in 2001 to 90% in 2012. However, the vaccination campaign for typhoid in an urban and semi-urban setting could only achieve 71%. School vaccination coverage is usually higher than vaccination at health posts due to access to a group of children, especially in areas where school enrolment is high, such as Nepal . The comparatively lower vaccination participation in our study highlights the importance of parental confidence, knowledge and communication of the vaccination administration group with the target population. The results of adjusted analyses indicate that there were three important areas that determined the participation: individual knowledge of disease and vaccine safety, information and communication, including prior information on the campaign, and communication by the school administration staff with the parents through permission slips, and prior experience with the vaccination administration authorities. Although vaccine demonstration projects do focus on social mobilization and communication as was in this project, a sustained effort over time as opposed to a short term strategy will have more beneficial effects. We did not find a statistically significant effect in usage of any particular social mobilization and communication material on the vaccination participation. The permission slip/consent form had a statistical significant effect on vaccination participation; however, we are unable to differentiate the effect of permission slip/consent form from the effect of a message from school. This could possibly have been due to the regular communication between the parents and the school and not just because of the letter as a mode of communication. We adjusted our final model for the income group, but we did not find a statistically significant association of parental socio-demographic factors with vaccination participation.
Information communication and social mobilization plays an important role in all public health programs especially in vaccine programs. New vaccine introduction in a country is a critical step and should involved bringing in major stakeholders, and the community. The recent examples of such efforts are introduction of strep. Pneumococcal Vaccine, Rotavirus Vaccine, and Human Papilloma Virus Vaccine. These vaccine introduction initiatives have from the very beginning have focused on population information need and the channels that will affect decision making in vaccine update. The global polio eradication campaigns in India proved that community engagement plays an important achieving vaccination targets.
The study has limitations that are mentioned here that limits are analysis of these variables with the outcome. 1) Parents’ educational background, financial backgrounds, and cultural backgrounds can have huge impacts on this study. Comprehensive background information on respondents was not collected; 2) more than two thirds of our sample is from the metropolitan area.
Vaccination campaigns with vaccines that are being newly-introduced in a country’s immunization program often focus on short term strategies for information communication and social mobilization. The factors that determine compliance with a new intervention need a long-standing channel of communication between the organizing group and the target population. This may not be possible with projects such as ours; however, the results need careful interpretation if participation in intervention studies is found to be lower compared to routine programs. Additionally, prior experience and knowledge of disease and the intervention play a major role for wider coverage of preventive programs in the desired population, such as vaccines.
The authors wish to thank Pradhan YV, Sue Kyoung Jo, staff at Child Health Division, the District Public Health office, Lalitpur Sub-Municipal City and the community in the district for their support. This study was conducted through a grant (Vi Vaccines for Asia Initiative) from the Bill & Melinda Gates Foundation. The International Vaccine Institute receives core funding support from the Governments of Korea and Sweden. We are especially thankful to Dr. Raul Gomez for the editorial review of the manuscript.
Citation: Khan MI, Bajracharya D, Pach 3rd A, Upreti SR, Sahastrabuddhe S, et al. (2016) Factors Associated Participation in a School Based Typhoid Vaccination Campaign in Nepal. J Vaccines Res Vaccin 2: 004.
Copyright: © 2016 Imran Khan M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.