DO YOU FEEL SICK? SAY A‘ HH’ INTO THE SMARTPHONE
Sonde Health says its app is able to detect signs of Covid-19 and other respiratory illnesses in your voice, and will tell you to visit the doctor
If you have ever told a friend they don’t sound very well and should visit a doctor, you will get the idea behind Sonde Health’s apps.
The company’s technology analyses a voice sample collected via a smartphone to assess whether the user has symptoms of respiratory illness. An app to assess mental health conditions such as depression is coming soon.
Sonde Health was founded before the pandemic, and its respiratory illness app was designed to search for symptoms of asthma and chronic obstructive pulmonary disease – but it is also able to recognise symptoms of Covid-19.
Sonde Health’s apps are part of a burgeoning field of voice analysis technology which focuses on finding biomarkers for respiratory health, mental health and emotional states.
Sonde Health’s US-based CEO, David Liu, says the technology does not provide a medical diagnosis, as it is not authorised to do so by the Federal Drug Administration. Sonde Health sits in the wellness sector as a preventive care technology.
“We identify the symptoms of health conditions or diseases,” Liu says. “We don’t diagnose for disease. We are very good at finding signals that tell us that the symptoms of a particular disease are there. We detect these symptoms and give the user actionable data.” After the test, the app tells users if they need to visit a doctor for a medical diagnosis.
Sonde Health’s technology combines acoustic research and big data with a knowledge of the physical mechanics of voice production. The body uses certain physical functions to produce speech. When we are ill, parts of our bodies malfunction, or perform differently, and changes in our voice occur as a result.
Diseases such as Covid-19 affect the upper and lower respiratory tracts and, as a voice needs air to work, can significantly change the sound of the voice.
“There are hundreds of different body parts that have to come together in human beings for us to speak. When symptoms of a disease like flu, or Covid-19 or asthma, occur, they will have an impact on the sound of your voice. Some of the changes are audible by the ear, most of them of are not,” Liu says.
The Sonde Health app captures the granular details of a voice via the mic of a smartphone and sends it to the company’s machine learning technology in the cloud, where the big data element of the process comes in. Sonde Health has a database of about 1 million voice samples, including those of people with diseases as well as healthy people.
The samples have been grouped into 4,000 “features”, which are biomarkers for the symptoms of various diseases. Sonde Health’s algorithms work out if the user’s voice matches certain features in the databank, and if it does, the app tells them that they may be exhibiting symptoms of a particular disease.
“The physiology of your body changes when symptoms of disease begin to take hold,” Liu says. “A very simple example is an upper respiratory condition or an illness like strep throat or asthma. There are certain things about those diseases that will impede or impinge upon the normal function of your brain, all the muscles of your mouth and throat, and your lungs and your heart. The diseases produce certain vocal feature changes in your voice.”
To use the app to test for respiratory illness, users need to say a six-second “ahh” into the mic on their smartphone, and complete a short screening test about their current known illnesses. The forthcoming Sonde Health app which tests for mental health conditions works a bit differently – users must speak a sentence continuously for 30 seconds.
One of the advantages of using Sonde Health, Liu says, is that if a user keeps using the app, their voice sample can be compared to itself, yielding greater accuracy. “We get a longitudinal data set – we can get multiple voice-over samples from an individual over time. We can then begin to form a baseline, and that baseline is incredibly powerful for us because then we can tease out underlying conditions like asthma. The baseline helps to make us more accurate,” he says.
Data privacy is a salient issue, and Liu says the voice samples in the Sonde Health database have been stripped of their personal identifiers, and that the user data related to customers will never be sold to advertisers. “We don’t make money by selling data to advertisers. That is not our business model,” he says.
Liu says apps like Sonde Health, which can offer users quick and regular health tests, will become ever more common. Such apps allow an individual to perform a test every day, giving them the information to take further action if they feel it is necessary. Sonde Health can pick up on symptoms before an individual has noticed them, he says, making it an important weapon in the armoury of disease prevention.
“Our data is much more actionable than a fitness tracker, and a hell of a lot more meaningful,” Liu says. “With the information that we provide, people will be able to make better health decisions, and will be better armed for their first meeting with a doctor.”
We identify the symptoms of … diseases. We don’t diagnose for disease
DAVID LIU, CEO OF SONDE HEALTH