By Makenzie O'Keefe

DENVER (CBS4)– A 4-year-old Colorado boy diagnosed with coronavirus, is now safely recovering at his home. Lincoln Zimmerman was diagnosed with the novel virus in early April, and spent a week at Rocky Mountain Hospital for Children undergoing treatment.

(credit: CBS)

The hospital said they have had four pediatric patients test positive for COVID-19.

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“When the doctor came in and told us he tested positive for COVID-19, I started to cry,” said Anna Zimmerman, Lincoln’s mother. “I wasn’t expecting it.”

In late March, Anna said her son Lincoln started to feel a little unwell.

“We had a couple of sneezes, a runny nose,” she said. “I thought it was allergies.”

Anna is a NICU physician at Rocky Mountain Hospital for Children, and after hearing about the COVID-19 pandemic in China and Italy, she was proactive about her family’s health. Before the stay-at-home order was even in place, she took Lincoln and his two sisters out of extracurricular activities to be safe.

“We didn’t let them go across the street. We didn’t take them to parks, we didn’t go to the neighborhood, nothing,” she told CBS4’s Makenzie O’Keefe. “We just stayed at home.”

Anna said her son’s mild symptoms lasted about a week, when suddenly the toddler came down with a fever of 104 degrees. She took him to the doctor to get checked out and they decided to put him on oxygen at home. His health however, started to worsen.

“He needed more oxygen, more support, more hydration,” she said. “So Monday is the day we went to the hospital.”

(credit: CBS)

That was about a week or so after his first symptoms began. Anna said their not sure whether the sneezing and runny nose was related to COVID-19 or if that was something that he developed later.

In the hospital, she said at first, his tests didn’t point to the virus.

“Even when we got there, his X-ray didn’t look like it, his timing wasn’t the same, his initial blood count didn’t look like it,” she said. “Those first two days in the hospital he just really quickly got much worse.”

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That Wednesday she said Lincoln was tested again, and tested positive for COVID-19. Doctors and nurses with Rocky Mountain Hospital for Children worked diligently to care for Lincoln.

“We were in the hospital about seven days,” Anna said. “It was hard to watch. The coughing spasms are crazy. Those were the scariest for me, you could tell he couldn’t catch his breath.”

After days of treatment, Lincoln began to show signs of recovery.

(credit: Anna Zimmerman)

“You aren’t sleeping, you are holding your breath because you don’t know what’s coming,” his mom said. “And the moment you start to turn down that support it’s a weight off your shoulders.”

Reginald Washington is the Chief Medical Officer of the hospital. He said children are less likely to have all the symptoms adults do.

“The common symptoms are fever, cough shortness of breath, muscle aches, muscle pains, those kinds of things,” Washington said. “Kids have all those symptoms but with less frequencies than adults. So you have to be very diligent to think of COVID-19 as a possible problem.”

Washington also said progression is really slow and it takes a while before symptoms of coronavirus are developed, as it was in this case.

“We don’t know why kids are different yet there is still a lot to learn about this,” he explained. “We know some of the kids affected by this have underlying conditions like heart problems or lung problems, or asthma, but not all of them.”

He said health officials expect 2% to 3% of all the COVID-19 patients in the country are under 18 years old.

For the Zimmermans, this is a remarkable story of success as 4-year-old Lincoln in now recovering safely, at home.

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“He’s eating more normal, drinking more normal,” his mother said. “He looks like himself again.”

Makenzie O'Keefe