Viral Infections
A viral infection reliably causes four responses:
Increased temperature | |
Decreased blood oxygen saturation levels | |
Increased resting heart rate | |
Increased respiratory rate (breaths per minute) |

Self-Monitoring For Common Signs Of Viral Infection
Starting with HeartCloud Sync Version 1.1, we included a suite of tools to help you self-monitor potential indications of infection by visualizing day-to-day trends between four health data points. Each data point is displayed on the same chart as a daily average so that you can more efficiently see day-to-day trends.
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Blood OxygenRespiratory illnesses often negatively affect blood oxygen saturation (SpO2) levels. HeartCloud visualizes oxygen saturation data saved in the Apple Health app on your iPhone. You can get this data from the Apple Watch Series 6 or or manually enter pulse oximeters[1] readings into the Apple Health data from HeartCloud Sync. |
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Resting Heart RateIn many people, an infection causes your heart to beat faster. Your Apple Watch measures your resting heart rate in the background, often more than once per day. |
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Body TemperatureDepending on the type of infection, your body's temperature may rise. HeartCloud visualizes ºF or ºC temperature readings saved in the Apple Health app on your iPhone. Whether you use a "smart" thermometer that automatically saves a temperature reading's date, time, and value in degrees (or manually enter this information yourself), HeartCloud Sync helps you track temperature measurements more efficiently. |
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Breaths Per MinuteWhen a person is starting to fight an infection, increases in respiration rate, or breaths per minute, may occur. HeartCloud visualizes respiration rate from pulse oximeters saved in the Apple Health app on your iPhone. |
[1] A pulse oximeter estimates the percentage of hemoglobin in the blood that is carrying oxygen from the lungs to body tissues. Healthy saturation levels are ordinarily approximately 95-100%. |
What About Devices That Don't Automatically Sync With Apple Health?
Amidst the current pandemic, sales of pulse oximeters and thermometers have skyrocketed. However, many of these devices do not automatically save the date, time, and value to the Apple Health app on your iPhone.
Our iOS and web apps allow users to manually enter temperature readings from a thermometer and oxygen saturation readings from a pulse oximeter. When you add either from HeartCloud Sync, that reading is saved to Apple Health and then also automatically uploaded to your HeartCloud.io account.




Symptom Tracker
HeartCloud includes a way to store periodic, structured self-assessments that may help link various symptoms to coronavirus infection. Questions are based on official U.S Centers for Disease Control and Prevention (CDC) criteria and ask if you felt a variety of possible infection indicators within the last 24 hours.
Your answers are securely stored and encrypted in your HeartCloud.io account. Since you can share answers self-assessment with your doctor, along with the date and time it was completed, it helps more accurately track the timeline of potential symptoms and changes.
