I checked: no fever. Later that day, however, I developed a very slight — but certainly not continuous — cough. The next morning, my lungs ached, and it hurt to take a deep breath. My mum, an asthmatic, was already self-isolating. We agreed I should too, “just in case.”

I argued with my partner over the weekend. He had an event to attend in London on Sunday. Neither of us believed I had Covid-19, but I worried that if he brought it back from London, my current illness would make it harder to fight.

The pain in my lungs persisted. My muscles ached. I had the chills. Breathing became harder. I developed a sniffle. My temperature peaked at 37.1 degrees Celsius (98.8 degrees Fahrenheit), lower than the government’s warning of a fever of 37.8 (100). Then, Mum texted me a link to two papers published in the medical journal Gastroenterology in early March. Investigators in China found a significant proportion of coronavirus patients developed diarrhea, nausea and vomiting before respiratory symptoms.

The symptoms we had put down to stomach flu, norovirus, a chest infection and a cold, were starting to look more and more like the coronavirus. Days later, The American Journal of Gastroenterology published a study showing 48.5 percent of participants with Covid-19 experienced digestive symptoms, and those who did took longer to recover.

I was pretty certain I’d been suffering from Covid-19. But I’ll probably never know for sure. The British government’s policy is to test only those who have been admitted to the hospital with severe symptoms of Covid-19; I wasn’t. (This testing policy goes against W.H.O. guidelines, too.)

I felt terrible — and not just because of my symptoms, which have by now improved significantly. I feared how much I’d spread my infection. If I had known that diarrhea and vomiting were Covid-19 symptoms, I would have self-isolated when they appeared. As it was, I had been outside and with others during the first week of the illness, when the virus is most contagious.

I messaged those it was possible to contact — the friends I had seen at the cafe on that Sunday, people from the wrestling match, the friend who had stopped by for coffee — to ask if they had developed any of the same symptoms. I found three who had come down with symptoms (not limited to a dry cough and fever) roughly five days after seeing me — the median incubation period for Covid-19. I worried about those whose phone numbers I didn’t know. And I worried about how many each of them spread the infection to as well. How many people did the others infect? And how can we ever know the community spread of the virus, if we don’t test for it?

Abigail Tarttelin is a writer, actress and musician.

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