Safe in COVID-19: A platform to support effective monitoring of incidents during a pandemic

INTRODUCTION: The ongoing coronavirus pandemic is affecting the lives of millions of people, changing society by enacting new rules for social life, business and travel. The world community (i.e. international organizations, public administrations, businesses, and citizens) has conducted a huge effort in delivering digital solutions to properly address the challenges imposed. A multitude of approaches have been followed, towards achieving a wide spectrum of side goals. OBJECTIVES: This work presents a platform, designed for public health authorities, to effectively track suspect, probable and confirmed incidence cases in a pandemic by means of a mobile app used by citizens to provide immediate feedback. The aim has been to better support human tracers, and the platform must not be confused with proximity tracking apps. METHODS: The outbreak response tool was developed based on official information and guidelines, on top of an already existing personal health record app which has been extended, to properly accommodate specific needs that emerged during the crisis. RESULTS: The developed platform provides the framework to support return to the “new normal” in less time, with reduced stress and more security for individuals, more direct and safer management of patients by physicians, and better possibilities for monitoring the epidemic by public health authorities. Issues relevant to privacy concerns, and interoperability with available patient registries and data analytics tools were also examined to better support public healthcare delivery and contain the spread of the infection. CONCLUSION: In order for the foreseen benefits to be realized, there is a need to respect safety and security regulations, while at the same time conform to international standards and widely accepted medical protocols. Cross-border interoperability and the availability of appropriate links (i.e. publicly available interfaces) to relevant open data and national registries is considered to be of paramount importance.


Introduction
The coronavirus disease 2019 (COVID-19) is an infectious disease which was first identified in December 2019 in Wuhan, China, and has resulted in an ongoing pandemic other applications and registries using international standards, as well as compliance with approved medical protocols.
The preliminary conception of the described work is based upon existing work on personal health record systems [8], [9] and the development of integrated care solutions to effectively support personal health management and public health [10].

Methods
At the time this paper was written, all governments, health organizations and other authorities were continuously focusing on identifying the cases affected by COVID-19. The Center for eHealth Applications and Services of FORTH (CeHA 9 ), in response to national and European calls for meaningful digital innovation against the pandemic, voluntarily developed digital tools and services based on an existing personal health record platform, in order to assist public health authorities, healthcare providers and citizens to address the current challenge.
The development of the underlying platform followed a detailed requirement elicitation process based on the official information and guidelines of (i) the National Public Health Organization of Greece 10 , (ii) the Centers for Disease Control and Prevention 11 in the United States, (iii) the United Nations Public Health Unit 12 , and (iv) the World Health Organization 13 .
The modules of the Safe in COVID-19 platform were based on already existing tools and services developed in ongoing and past projects, such as BOUNCE [11], RELIEF [12], STARS [13], iManageCancer [14], as well as already existing software already developed by CeHA.
Applications for the involved stakeholders (public authorities, healthcare professionals, and patients) were built upon a common platform ensuring interoperability with existing modules and third-party systems. Safe in COVID-19 modules were incorporated into the personal health record platform to support symptoms recording and tracking, information sharing, personalized recommendations, communication, position tracking/ tracing, and public health visualizations. Privacy needs were considered at the very beginning of the system development following the privacyby-design approach [15] for the modular architecture, data flow and interactions. Data protection in accordance with the European GDPR 14 was also incorporated.

Relevant work
Mobile technology has been leveraged in a number of ways to control the spread of COVID-19, including to support knowledge translation. Mobile applications are accessible, acceptable, easily adopted, and have the ability to support social distancing efforts. As such, they have been widely developed during the first half of 2020 in an attempt to "flatten the curve" [16] of the increasing number of COVID-19 cases, providing information to all civilians and subsequently relieve the pressure on healthcare systems. To this direction, multiple apps and protocols have been designed to facilitate self-assessment at home, track statistics, and provide current updates.
Platforms like COVIDSafe 15 in Australia, for example, offer the ability to document registered isolation, to better understand the experience of those in isolation, to create a safeguard for isolated individuals, and to allow public health to conduct appropriate analysis and research.
COVID Symptom Tracker 16 developed in the US, helps track the onset and progression of symptoms with the goal of shedding light on the nature of the disease, to identify those at risk sooner, to pinpoint virus hot spots and to help slow the spread of the disease.
In addition, protocols like the Decentralized Privacy-Preserving Proximity Tracing (DP3T) [17], and the Apple and Google exposure notification application programming interface 17 (API), which are currently in testing phase in Switzerland, implement a hybrid solution in which each participant is the sole owner of its own data until it is necessary to transmit its tokens to a central server to declare its status as "infected". Each participant generates tokens at regular intervals and then broadcasts them. The tokens generated (from seeds known exclusively by the device that emits the proximity messages) do not allow to trace the identity of the user. Only if a user is declared infected, can the tokens be retrieved to allow other users to "determine" whether or not they were in the vicinity of the infected user.
On the other hand, the Pan-European Privacy-Preserving Proximity Tracing (PEPP-PT 18 ) framework defines a protocol that simplifies the recognition of users found to be infected, while at the same time is trying to ensure privacy and security. The substantial difference between PEPP-TT and DP3T lies in the fact that in the former the tokens passed on are generated from information known to a central authority which must be trusted. When a user is declared infected, he has the option to send his information to the central server to warn other users who have been in contact with him. The action is voluntary also in this case.
When the contact becomes a case, the change in status is linked, through a common identifier, to a case database (i.e. a line list). The systematic use of common identifiers linking contact tracing, case line lists, and individual laboratory results is considered to be essential. The Global Outbreak Alert and Response Network (GOARN) has developed Go.Data 19 , a software application specifically designed to manage case-contact relationships and the follow-up of 15 https://www.health.gov.au/resources/apps-and-tools/covidsafe-app 16 https://covid.joinzoe.com/us 17 https://www.google.com/covid19/exposurenotifications/ contacts. Go.data has been deployed to over 35 countries in support of the COVID-19 Pandemic response.
Unfortunately, evidence-based assessment of those apps does not exist yet, even though healthcare systems rely on these as part of a toolbox of strategies to support social distancing and personal decision-making, to reduce the potential impact on overwhelmed clinical services. In addition, most of the available apps/ platforms have a single purpose, to serve either as symptom manager/ assessment tool providing news and statistics, or as information sharing/ training apps [18]. To the best of our knowledge, none of these comprehensively includes a full range of features. Despite the fact that online analytic dashboards for tracking COVID-19 20 are currently available, they are limited on presenting mostly recovered, and confirmed cases and deaths, without being able to present further statistics or make predictions.
Digital solutions can provide opportunities to support and strengthen health systems offering tools that contribute to the diagnosis, treatment, monitoring, and citizen empowerment through information, public health surveillance and epidemiology. In addition, an important need includes the development and utilization of decision support tools to assist policy optimization for minimizing negative socio-economic impact, while contributing to the containment of the pandemic. Social, organizational, and technological factors need to be addressed to facilitate the adoption of these eHealth tools [19]. Patients need to have a central role in elaboration of mobile app requirements for usable and meaningful solutions. Uptake of the mobile eHealth resources will require a significant change in management efforts and the redesign of existing models of care [20]. One key factor in the successful development and deployment of COVID-19 relevant solutions at a national level is the establishment of a close cooperation with public authorities. Since public health falls under their jurisdiction, it is a necessary step in making applications operational. The development and practical deployment of digital platforms can become a reality only through following existing medical protocols, implementing interoperability with national registries for citizen identification and COVID-19 specific information, ensuring quality through testing, and establishing the appropriate legal framework. The implementation of the appropriate interoperability protocols is particularly important to leverage the individual benefits of mobile apps and other digital technologies. An interoperability layer can enable the various such solutions to exchange meaningful data in the appropriate format for optimal communication not only with national registries but also with other digital solutions such as electronic health records and hospital information systems. As technology adoption barriers have decreased due to the current pandemic, digital transformation in healthcare can accelerate the use of novel technologies. eHealth solutions can be implemented rapidly and can offer essential tools in supporting the COVID-19 pandemic for all stakeholders including citizens, healthcare providers, policy makers and governments, promoting coordination to ensure appropriate management of this crisis. Healthcare systems can act as drivers of change and facilitate the adoption of similar eHealth technologies based on need.

Safe in COVID-19
Safe in COVID-19 is a digital platform that was developed in an effort to support national authorities in Greece. The platform provides tools for public authorities, healthcare professionals, citizens and their families offering an integrated care perspective to the ongoing pandemic. It provides services to help: • Public Authorities to have a better picture of the actual situation regarding the existence of suspect, probable and confirmed COVID-19 incidents and be able to make appropriate decisions based on the self-reported symptoms of the citizens and the relevant real time data that are available. • Healthcare professionals to communicate with citizens who report COVID-19 symptoms, manage their patients, as well as to reduce direct contact with suspected cases. • Citizens and their families to record data on symptoms related to COVID-19, carry out self-assessment of their health condition as well as have access to personalized information/ instructions from healthcare professionals (physicians).
A typical use case supported by "Safe in COVID-19" is the following: • A citizen is confirmed to have a contagious disease such as COVID-19. • The case is reported to the public health authorities and is managed by local healthcare providers. • The citizen is being interviewed to find out who he/ she was in close contact with. • The app is activated (voluntarily) and the citizen, is offered the option to record his/ her daily health status and to communicate on line or on demand with healthcare professionals, if needed, in order to receive further instructions and/ or alerts. • Once the contacts are traced, workers in public health communicate with them to provide screening, testing, counselling and/ or treatment. • The contacts traced also have now the app activated for them to monitor the progress of their own health and to support better disease control.
The information that the contact tracing teams gather on each contact should be entered into a database, such as the COVID-19 patient registry provided by national authorities, with the necessary data for the treatment and control of the pandemic being available to the involved bodies.

Architecture
The platform architecture is shown in Figure 1 and consists of the Application Tier that provides front-end applications to end-users, the Business Logic Tier that offers the intelligent functionality, and the Semantic Tier that stores and processes all available data. All these layers are supported by security and integrity services.

Application tier
The Safe in COVID-19 solution consists of a web application for public health authorities, a web application for healthcare professionals, and a mobile application (Android/ iOS) for citizens.
The web app for public health authorities (Figure 2) supports the strategic planning of the involved authorities by giving a complete picture of the status regarding the spread of the disease at national level and the measures taken regarding the provided healthcare services.   The mobile application for the citizen (Figure 4) supports the recording of health status on a daily basis and synchronous or asynchronous communication with healthcare professionals in order to receive personalized instructions for managing their health. When symptomatic, the following minimum set of data can to be collected: date of symptom onset, referral criteria (based on clinical severity and presence of vulnerability factors), contact's isolation (at home, at the hospital, or at other self-isolation facility), whether a sample has been taken (date of collection). Daily follow-up of signs and symptoms supported in a contact tracing form include fever (perceived or measured, and reported or observed), and other signs and symptoms: sore throat, cough, runny nose or nasal congestion, shortness of breath or difficulty breathing, muscle pain, loss of smell or taste, or diarrhea. Main functionalities supported include: (i) citizen registration, (ii) initial self-assessment based on a questionnaire for underlying diseases related to COVID-19 (this includes chronic lung disease, severe heart disease, immunosuppression, diabetes, renal failure, liver failure and morbid obesity), (iii) recording of symptoms which are related to COVID-19 and self-assessed by the citizen using a Visual Analog Scale (VAS) that include cough, sore throat, shortness of breath or difficulty of breathing, fatigue, muscle pain, headache, runny nose or nasal congestion, diarrhea, loss of taste or smell, (iv) recording of vital parameters related to COVID-19, such as body temperature, oxygen saturation (SPO2), breathing rate, systolic and diastolic blood pressure and heart beats,

Business logic tier
This tier consists of middleware services necessary for enabling communication between healthcare professionals and citizens, symptom tracking, managing personalized information and user profiles, personal health records, position tracing, and recommendations. As the Safe in COVID-19 framework is based and significantly extends a fully-fledged PHR system, state of the art communication, user profiling and personal health records come out of the box, whereas the specific COVID symptom monitoring and recommendations along with the position tracking have been implemented specifically for addressing the COVID-19 outbreak. All the services communicate with the semantic tier to retrieve, update and store data, which are further visualized and presented to the user through the application tier.

Semantic tier
This tier includes a data lake where all available data are staged. Those include data collected by the mobile and the web apps, additional data about healthcare resources and geolocation information, as well as external open data sources and registries. All these datasets are staged in the data lake that currently supports relational and NoSQL databases. Independent of the model the individual data use, a highlevel ontology has been used to integrate, homogenize and make FAIR the available COVID-19 data. To this purpose the WHO COVID-19 rapid version case record form (CRF) semantic data model has been used for exposing the data, along with the MHA Semantic Core Ontology [21]. The WHO COVID-19 rapid Version CRF Semantic Data Model is an approach to model all relevant COVID-19 data for the various clinical research forms as recommended by WHO. On the other hand, the MHA Semantic core ontology has been developed through the MyHealthAvatar and the iManageCancer projects [21] for modelling all health information for individuals. A screenshot showing the intersection of the modules of the two ontologies used is shown in Figure 5. The available data in the platform are mapped [22] to the aforementioned ontologies in order to be homogenized, and subsequently queried and exported. Besides the mapping to aforementioned semantic models, annotations are also available on the available data using terms from the included modules, whereas specific attention is paid to the fact that the ontologies are continuously evolving artefacts [23] [24].
For accessing the available information, both in its native and in its semantically uplifted form the available APIs have been implemented and are available. The data access APIs is used by the business logic tier modules to enable efficient data access and can also be offered to external services that require access to the data.

FHIR interoperability
Fast healthcare interoperability resources (FHIR) have been used for the representation of the medical data related to COVID-19 [25]. More specifically valueSet for COVID-19 Patient Reported Outcome Observations 21 , that includes the following symptoms: cough, fatigue, pain in throat, dyspnea, headache, diarrhea, nausea, loss of sense of smell, and temperature has been adopted. This valueSet is used for the recording of vital parameters related to COVID-19 for the citizens' application. FHIR resources (i.e. Problem and Condition resources) are also appropriate for representation of the underlying diseases related to COVID-19.
In addition, the Simplifier.NET 22 project contains FHIR resources covering patient self-assessment, remote practitioner-driven clinical assessment and subsequent exams for patients whose epidemiological assessment has already been completed, as well as resources to track the clinical outcome defined for them (home-quarantine, admission to intensive care or non-intensive care, etc.). It also supports telemedicine/ self-monitoring to track the subsequent telemedicine process for home-quarantined subjects and selfmonitoring of relevant clinical parameters.
Moreover, the Situational Awareness for Novel Epidemic Response Implementation Guide 23 , published by the HL7 International Public Health Workgroup, enables transmission of high-level situational awareness information from initially inpatient facilities to centralized data repositories to support the focus and response to novel influenza-like illness, such as COVID-19. This implementation guide addresses the need to have immediate awareness of available aggregate status, 22 https://simplifier.net/covid-19 23 http://build.fhir.org/ig/HL7/fhir-saner/

EAI Endorsed Transactions on Bioengineering and Bioinformatics
Online First outcome, and resource availability for public health and emergency response agencies to support monitoring, coordination, and management. It also supports reporting of data required by public health and emergency response agencies to address management of the COVID-19 Pandemic. The implementation guide includes resources for supporting bed availability reporting, medical devices reporting and questionnaires. Also produced new codes and developed value sets and guidelines for coding conditions and situations related to COVID-19 including diagnosis, evaluation, treatment, procedures, and medications associated with the disease. FHIR Server is the module where all the patient input coming from the citizen's application is published. Based on the resources and the implementation guides mentioned before, relevant to COVID-19 data can automatically be published through a FHIR Server, further enabling interoperability with external health systems. The web app for public health authorities and healthcare professionals consume these data and present to the end user of each application. The citizen's app can also act as a consumer of the FHIR server, in order to retrieve the personalized recommendations that healthcare professionals published to the FHIR server through the healthcare professional web app. Safe in COVID-19 retrieves the test results from the FHIR server and present them to the end users. All the above transactions with the FHIR server follow the FHIR RESTful API specifications.

Security considerations
The development of the platform was guided by privacy and data protection principles [26]. Effective cybersecurity controls have been used to protect the availability, authenticity, integrity, and confidentiality of data. Epidemiological frameworks and other safeguards have been considered. The common EU toolbox presents a detailed list of these requirements and elements [27].
Safe in COVID-19 modules do not process patient identification data but only the unique code generated pseudo-randomly by the health authority to confirm COVID-19 cases. The data processed have been minimized and encrypted in order to enhance security and privacy. Secure coding principles have applied and all network communications between the modules are encrypted. The Safe in COVID-19 app for the citizens is consent-based [28] with full information of intended processing of data.
Despite the common belief that the role of digital surveillance and tracking is critical in containing the COVID-19 outbreak, at the moment the adoption of the presented approach relies on the individuals' willingness to use the proposed tool(s).

Execution environment
The described platform has been implemented to execute autonomously on mobile devices so as not to burden both the network and the central infrastructure.
When an app is used offline, there is a minimum set of actions and data that have to sync with the server. Synchronization is performed whenever an internet connection is available. For the web app, user actions are stored in IndexedDB as jobs to sync. As soon as the network is available, these jobs are processed one by one. The mobile app uses both client-and server-side storage.

Host Requirements
The platform can be hosted at any modern Cloud infrastructure. Nevertheless, some minimum requirements are proposed so that it can operate at its optimal capacity, without delays or interruptions: • Virtual machines using vmware software (ver. 6) in computing x86 or x64 architecture systems. • Storage using 3-tier disk technologies.
• Network equipment for the interconnection of all the above virtual machines and internet access through the national network for public administration. • Protection using demilitarized safety belts (DMZ's).
• Load balancing mechanisms using L4 to L7 techniques.
• Ability to provide secure socket layer (SSL) offloading and acceleration mechanisms. • Security audit log system to record security-related system information. • Distributed denial of service (DDoS) attack protection.
The proposed configuration is depicted in Figure 6.

Network Requirements
Regarding the internet connection infrastructures, connection to public administration networks (such as SYZEFXIS 24 in Greece) is proposed, with a doubledirection optical ring of Metro Ethernet technology, in high-availability (active-standby).

Supported browsers
The following browsers are supported: Complying with the above specifications can ensure the correct and smooth operation of the platform without interruptions and problems.

Desktop
At the same time, the operation and use of the application is enabled by a very large number of users, while the support of L4 to L7 load balancing techniques in combination with the "offline" operation and the asynchronous synchronization guarantees that there will be no burden on the network load. 24 https://www.syzefxis.gov.gr/

Discussion and conclusions
This paper presented a digital platform with applications for public health authorities, healthcare professionals and citizens to support surveillance of suspect, probable and confirmed cases outside the hospital. The described tool can be used for self-reporting of symptoms by contacts and currently is not linked to proximity applications. The solution supports return to the "new normal" with less stress and more security for individuals, more direct and safer management of patients by physicians, and better possibilities for monitoring the epidemic by public health authorities.
Foreseen benefits for public health authorities include decongestion of the healthcare units (hospitals and specialized primary care centers) in situations that prevent citizens from attending health institutions (hospitals, specialized health centers) to receive the relevant diagnostic test, provision of real-time information on the evolution of suspected, candidate and confirmed cases, online monitoring of the spread of the virus, and decisionmaking support regarding required measures to be taken. Benefits for citizens include systematic recording of symptoms, provision of help for self-assessment of virusrelated symptoms, and access to personalized information, instructions and reminders about their symptoms and health status. Benefits to healthcare professionals include support in managing the patients traced/ monitored, reduced time for direct contact with patients, and improved working conditions. In order for these benefits to be realized to their full range, it is important to have an interoperability framework such as the one already described in [29] to connect with the relevant national registries and digital health services.
The effectiveness of such a tool depends on several, interrelated factors: (i) a comprehensive national epidemiologic strategy articulating instrumental support to the public health system, (ii) n appropriate architectural, technological but also organizational model of implementation, and (iii) widespread connection with mobile devices, while acknowledging that considerable segments of the population are unable to acquire or use them, in particular high-risk groups such as the elderly.
Putting such a tool in operation requires close cooperation with public authorities for the development and deployment of the solution at a national and international level, compliance with approved medical protocols [30], interoperability with national registries for citizen identification and COVID-19, quality assurance, and the existence of the appropriate legal framework.
There has been enough evidence to support that digital solutions can play an instrumental role in integrated care in the era of COVID-19. Implementing digital platforms at a EAI Endorsed Transactions on Bioengineering and Bioinformatics Online First D.G. Katehakis et al.
Safe in COVID-19: A platform to support effective monitoring of incidents during a pandemic 9 larger scale depends on the flexibility and sustainability mechanisms existing within the organization of healthcare systems. Considering the several benefits these technologies can have requires taking the responsibility to act in an adaptable way to ensure health systems and people continue to benefit. Existing healthcare services and infrastructures can greatly benefit from innovative digital solutions when they adopt a policy for integration and interoperability in support of the wider digital market.