“I haven’t been able to have a clear thought in two and a half years,” he told me.

Leeming is one of at least 65 million people worldwide who has the condition named long COVID–where someone infected with the SARS-CoV-2 virus continues to have symptoms of COVID for three months after their initial infection, or well beyond. Research on long COVID is still limited, and little is known about the best way to treat or prevent it.

Leeming, who is based in London, had gotten COVID during the second major wave, back in September 2020. He was 29 years old at the time, fit and healthy, and had never had a medical condition in his life, he says. But what started as a mild COVID infection that was easing up after only a couple of days ultimately turned into something much more. Leeming’s symptoms—which included severe chest pain, intense fatigue, and brain fog—continued and worsened until “I was barely able to stand,” he says. A cardiac MRI scan he paid for out of pocket in 2021 revealed that he, at the time, had myocarditis, which is inflammation of the heart muscle and is considered to be one of the most dangerous long-term cardiovascular complications of COVID.

Now in late January 2023, Leeming may look completely normal as we chat on a video call, but he doesn’t feel it: He struggles with chest pain and nausea, and, similar to many long COVID patients, is unable to exercise, as too much activity can significantly worsen symptoms. 

In the last two years, Leeming says he has been repeatedly written off by doctors or told that it was all in his head, particularly as no problems came up on his bloodwork. He resorted to finding methods to manage his symptoms on his own, and, last year, he and his co-founder Luke Martin-Fuller began to assemble Visible, a San Francisco- and London-based health tech startup that helps people track data and monitor long COVID and other chronic conditions.

Visible released the beta version of an app at the end of last year, which attracted 16,000 users in less than two months, by using a chunk of the $1 million in pre-seed funding they raised from VCs like Calm/Storm, Octopus Ventures, and Hustle Fund to do it. The Visible app allows users to track their symptoms and measure biometrics like heart rate and heart rate variability by using a smartphone camera. Users can also opt into research from approved academic partners, and, for a subscription fee, can add an integration with an activity tracking device to manage activity levels and digital biomarker data.  

Courtesy of Visible

Visible is planning to launch a premium version of the chronic illness health tech platform this summer, which will include things like real-time notifications on when a person is overdoing it and needs to slow down. Visible is also developing digital biomarkers that are specific to long COVID. Leeming says Visible plans to go back to market to fundraise in the next few months.

Health tech was a new field for Leeming when he and Martin-Fuller started building Visible. Leeming has a background in electric vehicle design, and, most recently, both he and Martin-Fuller were working in product at London-based fintech Moneybox. But Leeming’s own experience trying to address long COVID symptoms ignited a new passion.

Visible has several long COVID or ME/CFS (chronic fatigue syndrome) experts on its advisory board, including David Putrino, who is the director of rehabilitation innovation at the Icahn School of Medicine at Mount Sinai. And the company has attracted a series of employees who have a vested interest in the company’s success. More than half of the startup’s team has a lived experience of either long COVID or ME/CFS—which has made Leeming, who is Visible’s CEO, more thoughtful when it comes to providing adequate health insurance for his team and increased flexibility for taking time off, he says.

But it’s precisely the team’s personal experience with chronic illnesses that has attracted some of its investors to the cap table. Eric Bahn, co-founder and general partner of Hustle Fund, says he likes to invest in a team building a product that can improve their own lives, and who can test it out on themselves. The mission was also very personal for Bahn, who was diagnosed with the chronic illness ulcerative colitis, an incurable inflammatory bowel disease, approximately nine years ago.

“This is exactly in the wheelhouse of the kind of company that I’ve always dreamed of supporting—a team that just understands it, and frankly, has founders with deep, deep empathy,” he says.

A constructive ripple effect of COVID has been the attention it has drawn to pre-existing, pervasive chronic conditions—such as chronic Lyme disease, Fibromyalgia, or Lupus—diseases that have historically been misunderstood, under-researched, and difficult to diagnose and treat.

“I think this is the beginning of a new sea of change in invisible illnesses, like long COVID and Lupus, where we start to take these conditions more seriously and we start to focus not just on keeping people alive—but then the quality of life,” Leeming says. 

See you tomorrow,

Jessica Mathews
Twitter: @jessicakmathews
Email: jessica.mathews@fortune.com
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Jackson Fordyce curated the deals section of today’s newsletter.

VENTURE DEALS

- Boston Metal, a Woburn, Mass.-based decarbonized steel production company, raised $120 million in Series C funding. ArcelorMittal led the round and was joined by Microsoft's Climate Innovation Fund and SiteGround Capital.

- Sentra, a New York and Tel Aviv-based data security posture management company, raised $30 million in Series A funding. Munich re Ventures and Standard Investments co-led the round and were joined by INT3, Moore Capital, Xerox Ventures, Bessemer Venture Partners, and Zeev Ventures. 

- Q-CTRL, a Sydney, Australia-based quantum infrastructure software company, raised $27.4 million in Series B extension funding. Salesforce Ventures, Alumni Ventures, ICM Allectus, Mindrock Capital, Airbus Ventures, Data Collective, Horizons, Main Sequence Ventures, Ridgeline Partners, and others invested in the round.

- 2ULaundry, a Charlotte-based mobile laundry pickup and delivery service, raised $20 million in Series B funding led by Level 5 Capital Partners. 

- PortPro, a Jersey City-based transportation management software company, raised $12 million in Series A funding led by Avenue Growth Partners.

- Sovereign Labs, a blockchain scaling company, raised $7.4 million in seed funding. Haun Ventures led the round and was joined by Maven 11, 1KX, Robot Ventures, and Plaintext Capital. 

- Dasseti, formerly Diligend, a New York-based due diligence software company, raised $6 million in Series A funding led by Nasdaq Ventures.

- Dalia, a Boston-based recruitment marketing automation platform, raised $5 million in Series A funding. Lewis & Clark Ventures led the round and was joined by the family office of Paul Forster, SaaS Ventures, FJ Labs, Remarkable Ventures, and others. 

- TBD Health, a New York-based sexual health care provider, raised $4.4 million in seed funding. Tusk Venture Partners led the round and was joined by Springdale Ventures, Human Ventures, Expansion VC, Starbloom Capital, Hyphen Capital, and The Community Fund, and other angels. 

PRIVATE EQUITY

- PestCo Holdings, a Thompson Street Capital Partners portfolio company, acquired the assets of Romney Pest Control, a Houston, Lewisville, and Selma, Texas-based pest control company, and Phenom Pest Protection, a Columbia, Md.-based pest control company. Financial terms were not disclosed. 

- The Riverside Company acquired EnAppSys, a Stockton-on-Tees, U.K.-based data and analytics provider to the European energy market. Financial terms were not disclosed.

IPOS 

- Structure Therapeutics, a San Francisco-based chronic disease biotechnology company, plans to raise up to $134.25 million in an offering of 8.95 million ADSs priced between $13-15 per ADS. 

FUNDS + FUNDS OF FUNDS

- Convergence Partners, a Johannesburg, South Africa-based buyout firm, raised $296 million for a fund focused on acquiring African technology assets. 

PEOPLE

- AE Industrial Partners, a Boca Raton, Fla.-based private equity firm, promoted Jennifer Essigs to head of ESG.

- Bernhard Capital Partners, a Baton Rouge, La.-based private equity management firm, hired Rhoman Hardy as an operating partner. Formerly, he was with Shell.

- CRV, a San Francisco-based venture capital firm, promoted Caitlin Bolnick Rellas to general partner. 

- Kain Capital, a New York-based private equity firm, hired Bret Cummings as CFO and CCO. Formerly, he was with Macellum Capital Management.

- Summit Partners, a Boston-based alternative investment firm, promoted Scott Ferguson, Paul Furer, Mark Nordstrom, Dayton Ogden, and Sophia Popova to partner; Chris Bon, Ali Dowd, Mark Hexamer, Chelsea Jurman, Nick Oppedisano, and Jono Pagden to principal; and Jonathan Gilman, Andy Lee, and Irina Müller to vice president.