Child Vaccination in Peru: How to Support it Using Cloud

Computing and Blockchain

Arthur Valladares-Nole, Yohan Yi-Chung and Daniel Burga-Durango

Department of Information System, Universidad Peruana de Ciencias Aplicadas, San Miguel, Lima, Peru

Keywords: Blockchain, Child Vaccination, Cloud Computing, Vaccination Management System, Security of

Information.

Abstract: Childhood vaccination is an important pillar for a country's public health system. However, in Peru there

was no adequate tool or technology that could be used by parents or guardians of children to monitor or

control the process. In this work, a technological solution based on Cloud Computing and Blockchain that is

implemented in the childhood vaccination system of Peru will be presented based on a diversity of previous

studies. Which focused on the analysis of the processes involved in vaccination, the system used, and the

main actors to provide the best possible solution. The presented solution seeks to support the increase in the

rate of childhood vaccination in the national healthcare system. We developed a system with functionalities

that enhance the weak points in the current process, it is deployed in the cloud for the operation and

connection with various services, and which takes advantage of Blockchain technology to ensure the

protection of information that is managed in the process. The results obtained in the validation tests were

satisfactory, obtaining a minimum compliance percentage of 99%. In this way, the system with the

Blockchain network complies with the pillars of security such as confidentiality, integrity, and availability.

On the other hand, the non-technical aspects to safeguard the security of the system that have to do with the

processes and actors involved in vaccination were also considered. With this, the fundamental pillars of

security (“CIA”) can be ensured to provide a solution according to the context of the protection of

transactional and medical data in Peru.

INTRODUCTION

Currently, the Covid19 pandemic (ONU, 2020) has

affected childhood vaccination around the world

(Unicef, 2021). This also affected Peru since there is

a reduction in the number of vaccines applied

(Andina, 2021) and the rate of the complete regimen

(INEI, 2021) received by children in the first years of

life. Added to the current context are other factors that

do not favor the childhood vaccination process,

increasing the chances of generating new infectious

foci, collapses in the health system, and deaths from

infections (WHO, 2021). In the studies of Ekouevi et

al. (2018) and Garcia et al. (2021), where information

on the vaccination of children between 12 and 24

months of age is collected, some of the reasons for

not following the schedule of vaccinations are

observed, such as the lack of an electronic card, the

lack of knowledge about the process, the absence of

a guide from a medical professional to guide them.

This point is very representative in the Peruvian

reality since there is not a massive public system for

the national childhood vaccination program.

Peruvian parents must use a physical card that the

nurses stamp or sign each time they go to vaccinate

their children. There is no efficient way for them to

follow up on the vaccination schedule and remember

all the appointments to schedule to immunize your

children. At the same time, they must take care of a

fragile element that is also easy to lose (physical

vaccination card), so that they can vaccinate their

children following the vaccination program

stipulated by the government. On the other hand,

there are studies like of Di Giuseppe et al. (2022) and

Lewandowska et al. (2020) that seek to know the

opinions and knowledge that parents have about

preventive vaccination issues and the willingness

they would have to apply them to their minor child.

In these, it is found that most parents are willing to

apply preventive vaccines to their children, however,

they do not follow the vaccination schedule and due

to ignorance, they are afraid of the adverse effects

502

Valladares-Nole, A., Yi-Chung, Y. and Burga-Durango, D.

Child Vaccination in Peru: How to Support it Using Cloud Computing and Blockchain.

DOI: 10.5220/0012125000003538

In Proceedings of the 18th International Conference on Software Technologies (ICSOFT 2023), pages 502-509

ISBN: 978-989-758-665-1; ISSN: 2184-2833

 2023 by SCITEPRESS – Science and Technology Publications, Lda. Under CC license (CC BY-NC-ND 4.0)

that the vaccines could have. Finally, studies of

Getman et al. (2018) and Arede et al. (2018) show

the influence that social networks have on the

opinion of vaccines, specifically the pro- or anti-

vaccine publications with which parents can interact

and contract more doubts about vaccination. These

points are important to emphasize in the context of

Peruvian society, since this paper focuses on finding

solutions that best fit to this context. The level of

basic academic studies in Peru is deficient, therefore

the studies mentioned above have more importance

since they are based mostly on the level of ignorance

that parents have and how easily they are influenced

by any unverified information mostly found on

social media nowadays. Due to the ways are being

sought to counteract these factors and increase the

rate of children vaccinated with the complete

schedule. The studies of Trumbo et al. (2018) and

Clarke et al. (2019) provide an analysis of the health

systems implemented in different

countries, including

Peru. In this you can see the weak

points, strengths

and lessons learned to implement these systems, and

how it improves the data collection process.

In Section II, the related work about using

Blockchain and Cloud Computing in healthcare is

described. In Section III, the architecture and the

solution are explained. In Section IV, it is described

how validate the solution against the CIA Triad. In

Section V, the results are shown through tables and

graphs. In Section VI, we conclude about the most

important findings of the results, limitations, and

future work.

RELATED WORK

The research carried out resulted in works like the

developed solution, which are systems based on

Cloud Computing and Blockchain technologies. This

is due to studies of Yang et al. (2018), based on Cloud

development, Pawar et al. (2022) and Shanthapriya et

al. (2020), based on Blockchain, where systems are

developed in the health sector using these

technologies independently and evidencing their

individual benefits. On the other hand, there are

studies such as of Omar et al. (2019), Mahajan et al.

(2020) and Mubarakali (2020) that combine these two

technologies in a single system to offer a solution for

the treatment of adequate medical records. The latter

focus their research on providing a solid and robust

system in terms of the security of medical data

protection, but which in turn is deployed within a

service in the cloud. These systems, however, are

oriented towards a more general approach within the

health sector. In addition to these studies, there are

works such as of Haque et al. (2021), Hernández-

Ramos et al. (2021) and Biswas et al. (2021) that

focus on the use of Blockchain technology to develop

solutions related to COVID-19 vaccination. These

seek to create a system that can globally certify the

vaccination of a person through unique certificates

using Blockchain technology and that can circulate

between countries without major inconvenience

when there were greater requirements for migratory

transit. Finally, there are solutions that apply

functionalities like those developed in our work. This

is the case of studies of Obi-Jeff et al. (2021) and

Cheng et al. (2020), which offer messaging systems

to improve the vaccination process in some countries

and thus increase the rate of vaccination. The latter

are developed based on the cloud and the

functionality of text messaging is very present in our

work as it is an effective reminder method within the

vaccination process.

METHOD

3.1 Architecture

The solution to be developed is based on the physical

architecture shown in Figure 1. The two main

technologies that will be used in the proposed

system are the Cloud Computing and the Blockchain,

these are represented by the yellow box that encloses

most of the development components, and the blue

box connected to the Rest API, respectively. This is

because Cloud Computing technology will provide

the infrastructure to be able to deploy the system that

will be created and services that will be helpful to

enhance our solution with great capabilities. Through

this, it is possible to save on hardware components

and adjust the capacity according to the need for

requests, so that the economic section will be covered

in a staggered manner. Some of the technologies that

will be deployed in the cloud will be the Reminder &

Notification Scheduler, which will be in charge of

sending reminders by mail and text message; the web

application, which will allow the end user to interact

with the entire solution; the MySQL database, which

will store the data used in the system; Finally, the Rest

API, which works as the core of the system,

processing the information and connecting all the

components. On the other hand, Blockchain

technology will be used for the robustness it can

provide in transactional data security that is managed

in the core activities of our solution.

Child Vaccination in Peru: How to Support it Using Cloud Computing and Blockchain

503

Figure 1: Physical Architecture.

In this way, the aim is to provide sufficient

functionalities and characteristics to the vaccination

system to improve the experience in the process of

vaccinating children and thus support the increase in

the vaccination rate. The Rest API will contain all the

logic that you want to process in the system, while the

web application allows the user to interact with all the

functions offered in the system to offer a user-friendly

experience. The database is the one that will contain

all the data that is managed in the system, while the

Blockchain will manage the critical transactional data

of the vaccination process. Finally, the Amazon SNS

and AWS Lambda components work together to

provide email and mobile text message reminders

automatically.

Some advantages that have this architecture are

modularity, scalability, and versatility of the

components. This allows to add or change things with

a minimal configuration.

3.2 Web App

The web app allows to the users to access to the

functionalities of the system for the vaccination

process. The functionalities of this web app are

divided in two groups: for the parents and for the

health personnel.

In the group of functionalities for parents are the

following functionalities:

Visualization of Vaccination Card: the objective

of this functionality is that the parents can see the

status of completion of their children's vaccination

scheme. With this functionality, they will be able to

immediately know what vaccines their children have

already had, when, where and who gave them those

vaccines, and what vaccines are still to be given as

can be seen in Figure 2. Parents with this functionality

will not need to have the current physical vaccination

card that deteriorates over time or can be lost, by

having this vaccination card digitally they will be able

to know the status of their children within the

vaccination process at any time and thus have better

control to comply with the entire vaccination

schedule for their children.

Figure 2: Visualization of Vaccination Card.

Next Dose Reminder: this functionality allows

parents to know the next doses that can be

administered to their children. With this functionality,

parents do not need to be aware of their children's

next vaccinations since they will receive reminders,

as can be seen in Figure 3, days before the date on

which the next vaccine can be given and thus comply

with their children's vaccinations on time and boost

their health at the right time.

Figure 3: Next Dose Reminder.

And in the group of functionalities for health

personnel are the following functionalities:

Visualization of Child Health Information: The

objective of this functionality is that the health

personnel can immediately view and at any time the

remaining and administered vaccines of a child. With

this functionality, they do not need to request the

vaccination card from the parents, since it would be

only enough to search for the child's health

information, like is shown in Figure 4, and view the

vaccines that must be given, and which ones have

already been given.

Registration of Dose Administration: This

functionality is focused on health personnel can

quickly and easily record the doses of vaccine that

have been administered. With this functionality, the

children's vaccination information will be recorded so

ICSOFT 2023 - 18th International Conference on Software Technologies

504

that both parents and health personnel can consult it

later and thus know the real completeness status of

the children's vaccination scheme. Figure 5 shows the

form that is filled out once the dose to be vaccinated

has been selected.

Figure 4: Visualization of Child Health Information.

Figure 5: Registration of Dose Administration.

Besides of the explained functionalities, the web

app also has the following: Visualization of Vaccine

Information, Vaccination Appointment Scheduling,

Vaccination Appointment Reminder, Registration of

Vaccination Campaign, Vaccination Campaign

Notification, Registration of Vaccine Inventory,

Visualization of Vaccine Inventory.

On the other hand, as part of the processes that are

involved in the functionalities provided to the parents

of the children who will be immunized and the health

personnel, it is sought that they have the least possible

access to information that does not correspond to

them or use a simple interface that allows the entry or

modification of data as little as possible. In addition

to protecting the data in terms of integrity and

reliability, there will not be an excessive use of

computational resources to load the different views

and functionalities of the service, which also ensures

its availability.

3.3 Blockchain

The Blockchain Platform developed with

Hyperledger Fabric and its API developed with

Node.js allow to the solution to record the

transactional data of the vaccination process in a

decentralized and secured way, also allow to the

different Health Organizations access to the same

information from the same data source. Internally, the

Blockchain Platform has 3 peers, as can be seen in

Figure 6. One smart contract written in JavaScript that

is used to register and query the doses, one certificate

authority to authenticate and authorize the agents, and

one orderer peer to manage the transactions and the

Vaccination channel where all the information of the

vaccination process flows.

Figure 6: Blockchain Diagram.

The information of the administered doses is

recorded in the Blockchain when the doctor registers

a dose administration in the web app and this

information is retrieved from the Blockchain when

the parent or the doctor query the health information

of the children. Internally, the REST API made with

ASP.NET Core calls the Blockchain´s API made with

Node.js to get or save the records. The Blockchain´s

API communicates with the Blockchain via the Smart

Contract and then returns the response to the REST

API; this one processes the info and finally returns the

response to the web app for the users.

EXPERIMENTAL SETTINGS

4.1 Calculation of the Experimental

Sample

According to the INEI, in 2022 there are 33 million

396 thousand 700 inhabitants in Peru, through the

following formula an approximate of the sample of

users that will be used for the test cases will be

calculated:

Child Vaccination in Peru: How to Support it Using Cloud Computing and Blockchain

505

Figure 7: Sample Formula.

Where:

•

The sample (n)

•

Total population (x): 33,396,700

•

The percentage of children from 0 to 11

years old (y): 22%

•

The total number of health facilities (z): 8148

•

Number of children per user (v): 2

•

Number of patients per health center (w): 230

The result that was obtained using the previous

formula is 453 users, with whom the validation tests

will be carried out. This amount is an approximate

calculation of users that there would be in a medical

center for the test cases.

4.2 Test Cases

For the validation of the security triad of the

technological solution based on Cloud Computing

and Blockchain for the child vaccination process, a

proof of concept (PoC) was carried out, with the

following test cases:

•

Test Case Nº1: Confidentiality of vaccination

records: This validation test consists of evaluating

the relationship between the number of tests that

accessed unauthorized information and the total

number of requests made.

Figure 8: Formula for % Confidentiality.

•

Test Case Nº2: Integrity of vaccination records:

The test case for this scenario is the verification

between the records that are entered and those that

are consulted to observe that there have been no

changes. This check relates to the total number of

tests performed.

Figure 9: Formula for % Integrity.

•

Test Case Nº3: Availability of vaccination

records: The availability test seeks to generate

requests for consultation of vaccination records and

vaccination cards.

Availability effectiveness is

measured by the

ratio of successful queries to the

total number of queries made.

Figure 10: Formula for % Availability.

The Blockchain network, of our system, is

configured with 3 organizations where each one has a

content peer. In this, the information of 453 users

between parents and health personnel will be placed.

With this, we will be able to validate the security triad

in our technological solution. Each test scenario has

been designed to validate an item of the security triad,

and thus, the correct functioning of the system will be

verified, fulfilling the success factors established for

the proof of concept.

Table 1: Success factors of PoC.

Test Case Success Factor

º1: Confidentiality o

vaccination records

Validate that at least 99% of the data

has not been accessed by

unauthenticated or authorized users.

º2: Integrity o

vaccination records

Validate that at least 99% of the data

have not been modified when

making the comparison.

º3: Availability o

vaccination records

Validate that at least 99% of the data is

available to authorized users who

request it.

RESULTS

5.1 Confidentiality

As shown in Table II, the records of doses

administered, and the vaccination card information

could not be accessed by unauthenticated users

without the respective permissions.

Table 2: Extract of the results of test case N°1.

Users

Could access the

information

Could not access

the information

Obtaining medical

records as an

unauthenticated use

460

Obtaining a vaccination

card for children who are

you

children

460

5.2 Integrity

According to table III, the records of administered

doses were recorded and compared satisfactorily.

ICSOFT 2023 - 18th International Conference on Software Technologies

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Table 3: Extract of the results of test case N°2.

Requests

Correct Fail

Doses

456 0

Obtaining and comparing

Doses Administered

456

5.3 Availability

In relation to the availability of the system, table IV

shows that the records of doses administered and the

information on the vaccination card could be

obtained satisfactorily in all requests.

Table 4: Extract of the results of test case N°3.

Requests

Correc

Fail

Obtaining Immunization

Records

453

Obtaining Vaccination

Car

453

In summary, a minimum of 906 interactions per test

have been carried out, simulating the 453 users

established in the calculation of the experimental

sample, carrying out the 2 interactions per test case.

In all the tests, as can be seen in Figure 13, a

satisfactory result was obtained, meeting the

minimum required of 99.9% effectiveness for the

proposed test case. This result, added to the controls

of the system itself for the protection of accounts,

data, and transactions ensures a robust system not

only against its technical aspect but also against the

processes and people involved in the child

vaccination system.

Figure 11: % Confidentiality, Integrity, and Availability of

vaccination records.

CONCLUSIONS

The research carried out in this work concludes with

the functional and technical validation of the

developed system. First, an investigation has been

carried out to clearly understand the cause of the

problem of low childhood vaccination. Through this,

functionalities have been designed to adapt to the

proposed system and to work in the context of the

Peruvian reality. With functions such as the SMS

reminder, it is considered that not many parts of the

country have a smartphone with an internet signal so

that they can be notified by email, specific

application, or social network. In addition, an attempt

is made to reinforce the idea that vaccines are

beneficial for the healthy growth of children and that

they are available free of charge and available to

parents in the medical centers listed in the system

according to the vaccine and location of the child.

Therefore, the functional proposal of the solution

has several edges considered according to the

investigation carried out on the problem and possible

similar solutions. Then for technical validation,

through the various tests and experiments, the level of

effectiveness for the protection of vaccination records

that the web application has with the use of

Blockchain technology was recorded. These tests

sought to verify that the solution complies with the

security triad such as Confidentiality, Integrity, and

Availability in data protection. After the tests, as can

be seen in Figure 13, the developed solution meets the

minimum established as a success factor with 99.9%

authenticity of information in all the tests carried out.

It can be concluded that the Blockchain network

integrated in the system complies with security

standards and protects vaccination records. This

added to the controls in the process that must be

carried out by the national health entities such as the

designated personnel who should have access to the

system and the important nodes described in the

architecture for the verification of the chain data,

among others. These considerations will allow the

solution to comply with the security standards

proposed in this work. Another type of research that

may arise because of the work carried out is the

definition of the implementation within the national

system and how it should be coupled to the laws or

requirements that exist within the Peruvian state. This

research could address other technical, legal, and

social aspects for the adoption of the proposed

solution. Finally, the research carried out solves the

latent problem of the lack of information for the

vaccination process and the safety of these in its

transmission, that is, a system that informs parents in

real time, being supported in the process. And

encouraged to follow the childhood vaccination

schedule, and at the same time provide protection in

Child Vaccination in Peru: How to Support it Using Cloud Computing and Blockchain

507

the security of highly critical data that is handled,

such as health records.

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