How we found Patient Zero

It was late April. I remember it being a somewhat quiet news day when I received the call. It was an editor on our international news desk alerting us that about 100 people had gotten very ill in Mexico City with severe flu-like symptoms.

They had no clue what was causing it at the time. The only thing health officials were telling us was that the patients had contracted a highly contagious virus that hadn’t been seen in humans before. The hunt was on: Dr. Sanjay Gupta and I hopped on the next flight out to Mexico City to track down the mystery virus that was getting so many people so sick.

Within 24 hours of arriving, the dense city of about 8 million people had figuratively turned into a ghost town. The mayor was urging people to stay inside; the hospitals were overcrowded; schools, public transportation, and restaurants closed their doors.

At one point, I remember walking down the unusually empty streets of Mexico City in awe. It was an eerie feeling, but also a defining moment for me as a journalist. I realized that people, not just in Mexico City, were scared of this unknown killer virus.

What was it? Would they be infected? What should they do? We didn't know it at the time, but H1N1 influenza was about to become a global epidemic and the world was already looking to us for answers.

A few days into our reporting on the ground, I received a phone call from CNN's senior executive producer for AC 360, David Doss. He had flagged a local health alert from the state of Veracruz, Mexico - there were unconfirmed reports that a little boy in the village of La Gloria was rumored to be “patient zero,” the earliest documented case of swine flu in the world.

Twenty minutes later, our crew was in the car, embarking on a three hour drive into the mountains of Veracruz to find the answer, the source of this outbreak. We had the wireless going on my laptop, phones to both ears, endlessly contacting our sources to confirm this story. We got it: Health officials confirmed to us that five-year-old Edgar Hernandez was in fact patient zero.

The catch? His village was in a very remote location with no phones, no electricity, no address to pop into our car’s navigation system. We knew finding patient zero would be a little like finding a needle in a haystack.

But as diehard journalists, this was the type of assignment we craved! I couldn’t wait to get there and to shuffle through that haystack. I knew in my gut we’d find him.

We walked around the village, visited their clinics, spoke to the locals. We met one man pulling his donkey up the dusty mountain road and asked him if he knew the Hernandez family. Turns out that man was patient zero’s uncle. He quickly walked us to the Hernandez’s home and we met Edgar, known as patient zero. He was no longer sick; he had survived the swine flu virus. He credits “ice cream” for curing him.

Being only 5 years old, Edgar couldn’t possibly realize the significance of being the first patient of what would be declared a global pandemic just two months later. But his mother certainly did. She feared Edgar could possibly be blamed for spreading it (which he did not) and she feared that their family would get sick again. She told us she didn’t understand what this virus was.

But that is why we were there - to find the source of this illness in order to understand it better. At this point, the CDC and the World Health Organization still didn’t know how the virus was spreading. But by discovering the earliest patients of an outbreak like this, health officials could begin to gather clues as to exactly what happened and, more importantly, how to treat and stop it from spreading.

As a journalist, there have been a few defining moments which I’ve felt I had a front row seat to something really big, to a small piece of history. Finding patient zero was one of the moments.

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