Apple in May 2020 introduced an Exposure Notification System, which was designed to let public health authorities and governments worldwide help people figure out if they've been exposed to COVID-19, and if so, what steps to take next to minimize the spread of the virus.
As the pandemic has waned, various governmental agencies have been gradually shutting down their Exposure Notification systems. With the expiration of the COVID-19 national state of emergency in the United States on May 11, 2023, the system is no longer functional in most of the over 30 states that had adopted the system.
Exposure Notification Explained
Exposure Notification started out as contact tracing, an Apple-Google initiative that was announced in early April 2020 to limit the spread of COVID-19.
Apple and Google created an API that is designed to allow iPhones and Android smartphones to interface with one another for contact tracing purposes, so if and when you happen to be nearby someone who is later diagnosed with COVID-19, you can get a notification and take the appropriate steps to self isolate and get medical help if necessary.
Determining whether you've come into contact with someone relies on your iPhone, which, using the exposure notification API, interacts with other iPhones and Android smartphones over Bluetooth whenever you're around someone else who also owns a smartphone, exchanging anonymous identifiers.
Apple and Google developed the underlying APIs and Bluetooth functionality, but they did not develop the apps that use those APIs. Instead, the technology was incorporated into apps designed by public health authorities worldwide, which can use the tracking information to send notifications on exposure and follow up with recommended next steps. Apple and Google also implemented an "Express" feature that allows Exposure Notifications to work in partnership with health authorities, but without an Exposure Notification app.
The APIs were created with privacy and security in mind, and app usage is opt-in rather than mandatory.
How Exposure Notification Works
Almost everyone has a smartphone, which makes them ideal for determining who you've come in contact with. Exposure notification has a self-explanatory name, and in a nutshell, the feature was designed to send you a notification if you've been in proximity to a person who is diagnosed with COVID-19.
Here's a detailed, step-by-step walkthrough on how it works:
- Two people, Ryan and Eric, are both at the same grocery store shopping for food on a Tuesday afternoon. Eric has an iPhone and Ryan has an Android phone, both with a health app that uses the exposure tracking API or the Express Exposure Notification feature.
- There's a long wait, so Eric and Ryan are standing in the checkout line together for approximately 10 minutes. During this time, each of their phones is transmitting entirely anonymous identifier beacons, and picking up the identifier beacons transmitted by the other person. Their phones know they've been in contact and store that information on the device itself, transmitting it nowhere else.
- A week later, Ryan comes down with COVID-19 symptoms, sees a doctor, and is diagnosed with COVID-19. He opens up his Android phone, verifies his diagnosis using documentation from a healthcare provider, and taps a button that uploads his identifier beacon to a centralized cloud server.
- Later that day, Eric's iPhone downloads a list of all recent beacons from people that have contracted COVID-19. Eric then receives a notification that he was in contact with someone that has COVID-19 because of his interaction with Ryan at the grocery store.
- Eric does not know it was Ryan who has COVID-19 because no personally identifiable information was collected, but the system knows Eric was exposed to COVID-19 for 10 minutes on Tuesday, and that he was standing close to the person who exposed him based on the Bluetooth signal strength between their two phones, allowing the app to provide the appropriate information.
- Eric follows the steps from his local public health authority on what to do after COVID-19 exposure.
- If Eric later comes down with COVID-19, he follows the same steps listed above to alert people he's been in contact with, allowing everyone to better monitor for potential exposure.
What You Need to Do to Use Exposure Notification
Using Exposure Notification in supported countries on a device running the latest version of iOS requires opening up the Settings app, selecting the "Exposure Notifications" section, and then tapping on "Turn on Exposure Notifications."
From here, your iPhone will let you know if an Exposure Notification app is available in your state, country, or region, providing details on how to download it. You'll also be informed if you can use Exposure Notifications without an app through the Express feature, or Exposure Notifications are unavailable in your area at this time.
Exposure Notification is a feature that's off by default, and actually using the API requires you to toggle on the feature and in some cases, download an app from a verified health authority. Many countries are developing country and state-specific apps that users can download.
Without explicitly opting in to use the Exposure Notifications feature, the Exposure Notification API on the iPhone doesn't do anything. Once you've downloaded an app and consented to using it, or consented to using the Express option, the Exposure Notification feature will become active on your smartphone.
Cross-Platform App Communication
Apple and Google have both worked to create APIs for exposure notifications that work together so iPhone and Android smartphones can interface with one another and you'll receive notifications if exposure happens even if the person you've been in contact with has an Android smartphone.
On iOS, Exposure Notification works on devices running... Click here to read rest of article
Article Link: Apple's Exposure Notification System Guide
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