Wilde, a retired teacher for the visually impaired, was in second grade in 1963. The measles vaccine was already available, but she remembers her mother telling her years later that it was not yet in widespread use.

I just remember being very sick. I remember lying on the couch in the living room and being very hot, like I was under the sun. My parents were arguing about what to do. They seemed to be millions of miles away. I felt very detached. My fever was very, very high, and I was not responding to them when they were speaking to me.

They were afraid to call an ambulance because they weren’t sure if I was well enough to be taken to the hospital. They called the pediatrician. The next thing I remember, he was patting my face and I could see his nose hairs and feel his breath. He was calling my name and trying to rouse me. He said, “We’ve got to bring the fever down,” and told my mother to run cold water in the bathtub. He was concerned about brain swelling.

They stripped me down, wrapped me in a cotton sheet and put me in the bathtub. I remember I felt like I was screaming with every bit of strength in my body.

My mother told me later, “You sounded like a dying kitten.”

I was in the back bedroom — in the dark — for several weeks to protect my vision. Gradually I got better. But I remember my eyes aching and me squinting. There are a lot of photos of me holding up a hand to shield my eyes.

Even now, when I get outside, my eyes ache. I also see little sparkles of light when I am in the dark. I know that is part of aging, but I still suspect if I had not had a severe bout of measles, I would have come through with far fewer vision problems.

McGregor-Foxcroft, a retired fingerprint technician, was in first grade in 1956. The measles vaccine was not yet available. Her older siblings had already had measles, as did many of her classmates.

I was 5 or 6. I had to be confined to a dark room, which was pure torture because I was just so bored. I couldn’t join the family for dinner. I couldn’t watch TV or any of that stuff. I couldn’t read.

I did something very naughty. I wrote a note on a piece of paper. It said, “Help, I’m being held prisoner.” And I pitched it out my bedroom window. And a neighbor showed it to my mother. And she just about had kittens.

She handed it to my dad and said, “The poor child is going crazy.”

Another week after that, I was allowed to read or write for an hour in the morning and an hour in the afternoon.

When I went back to school, I didn’t have the energy to walk home for lunch. It was probably three-quarters of a mile. Sometimes the neighbor would just drive me home. They knew how tired I got.

Tim, a software engineer, spoke to The Washington Post on the condition that only his middle name be used because his family has been harassed for not vaccinating him as a child. He became infected as an adult in 2016 after attending a crowded school event and was hospitalized.

I attended a family member’s school ceremony in a large auditorium. That same evening, I flew out to Las Vegas for a conference. About three or four days after I got home, I started to get sick.

I had a fever up to about 104. And I started to get this terrible headache that felt like the worst flu I had ever had combined with the worst hangover that I had ever had. A day or two after, I got out of bed to use the bathroom and I just collapsed in the hallway.

My partner drove me to an urgent care facility. They tested me for strep throat. They ruled out meningitis. They didn’t get a positive diagnosis of strep. But they prescribed me some antibiotics and sent me home. I took the antibiotics for a couple of days, but I just kept getting worse. And I woke up one morning and my body was just covered in red spots.

I ended up going back to the ER. Somebody asked me if I’ve been vaccinated against measles. This is when I realized that I wasn’t actually sure. I got confirmation from my mom that I had not been. They ran more tests and confirmed that I did, in fact, have measles.

They admitted me to the hospital into an isolation room. It was a teaching hospital, and it was the most surreal experience because no one had seen measles before.

They would bring in an army of doctors, and I had people asking, “Can I take a picture with you?”

I start getting calls from our health department. They want to track down what happened. It turns out, at the graduation I went to, someone flew in from out of the country and had measles. I must have somehow walked past them. I didn’t interact with anyone. I didn’t shake anyone’s hands. I didn’t have any conversations with anyone that was not my family. A little bit of errant air coming my way — that was all it took.

I was in the hospital three or four days. They sent me home under pretty strict guidelines not to go anywhere. This kind of started a whole new chapter of challenges. I lost about 20 to 25 pounds in the process. Walking upstairs, I would just be completely winded.

I ended up with immune amnesia, where it basically resets the body’s immune system. Everything that I would get exposed to — I would get sick. And every time I would get sick, I would get the worst version of being sick. Like, one of the bad colds I got turned into this full-on bronchitis where I just had no ability to talk. It totally changed the trajectory of my life for more than half a year.

I was recently diagnosed with an autoimmune disease, and I don’t necessarily know that it’s linked to measles. But I’ve kind of come to look at all of these things, at least in some way, as connected.

Tidwell, a retired attorney for the U.S. Postal Service, got sick as a kindergartner in 1961, before the first vaccine was available. He infected his pregnant mother, who passed it on to his baby sister.

My father was in the U.S. Army. We lived on an Army base in Wertheim, Germany. Everyone in my kindergarten class had measles. I got measles. I had bumps; I had the itching. As a young boy, you almost wanted whatever was going around. You didn’t think of it as potentially deadly. It was sort of a badge of honor.

My mother got them from me during the course of her pregnancy.

After my sister Dianna was born in March 1962, early tests showed she had some sort of visual problems. Doctors tried to correct them with surgery. The surgery got botched. Then, at some point, it became evident she was going to be developmentally challenged.

My father was transferred to Fort Sam, Tex., and that’s when [my sister] experienced her first epileptic seizure. Over time, she began to develop a swallowing disorder. She lived with the family for as long as my parents were able to take care of her. Then, over time, she began to lose motor control; she lost the ability to walk. She had recurring bouts of pneumonia, and recovery always left her at a lower plateau.

She died in October 1995. She was 33.

Dianna was the glue of our family. She never stopped believing in Santa Claus, which allowed the rest of us to take joy in playing along for a lot longer than most families get a chance to. Though she could never read, Dianna knew that the stories she liked were in books, and she liked making us read to her. Sometimes, she’d hand me two socks and insist on a puppet show. Nothing cracked her up more than when two puppets got into a fight. Keeping Dianna amused bonded us and taught me a lot about improvisation and flexibility that would serve me well throughout my life.

Leonhard, a retired teacher of English as a second language, was 6 in 1958. The first vaccine was not yet available. She was in a coma and unable to walk for a period.

I was 6 years old when I got measles. It was 1958. That summer my brother and sister and I got it. I remember being feverish and feeling miserable. I remember my mom sending me upstairs to get something off the dresser. I ran upstairs and all of a sudden my legs gave out and I couldn’t walk. I couldn’t move my arms. I remember it was too hard to carry me up and down the stairs, so they finally made a bed for me in the living room on the couch. My mom made a tent of blankets and put me in there and had me breathe steam and spit out phlegm because I guess they were concerned about pneumonia starting.

One night, I remember being swept up and taken to the hospital. I went into a coma on the way there. The last thing I remember was getting in the car. Everything went black. We went to the same hospital where my grandfather was dying. I thought when my parents put me in the car I was going to see Granddaddy. I remember talking to him. I remember saying to the people standing around the bed, “I want to go with him.” And they said, “No, you can’t go with him. You need to go back to your room.” The next memory I have I woke up from the coma.

That was like seconds to me, but I was in a coma for 30 days. I could talk, but I couldn’t walk. The doctor was saying, “Say, ‘The bear went over the mountain.’” And I said it.

And he said, “She’s okay. But she’ll never walk again.”

But I taught myself how to walk. While my parents were gone to close up the family home, I remember pulling myself from one piece of furniture to another, dragging my body and just willing myself to walk. I didn’t want to be in that wheelchair. When they came home, I ran up to them, “Look, I can walk!”

Mom told me that before I had encephalitis [a complication from measles], I could hear a story once and repeat it word for word. After that, I had a hard time learning. I had problems focusing in school. I lost my confidence. It was hard to learn and hard to relate to people. I worked really hard, graduated high school with honors. I have a master’s in English literature.

But I’m going to be seeing a neurologist because I’m experiencing some nerve things. I don’t know if it’s related to encephalitis.