Recording a video diary for ITV News on his way to hospital for a nine hour shift, he said: "It is going to be a challenge over the next weeks and I think we are all going to have to pull together, work extremely hard and be a unified as a nation in this."
Dr Alex - who rose to fame on the 2018 series of ITV's Love Island - is an Accident & Emergency doctor at University Hospital Lewisham in south-east London.
The 30-year-old said: "We're seeing the number of cases rising in the department and departments around the country as well.
"The number of cases of those people being unwell is rising.
"Intensive Care Unit beds are being taken up, ventilators are being taken up and this clearly is a really serious crisis.
"So I am expecting today to see […] the areas where patients are the sickest, to be really really busy. I know there is a lot of pressure on hospitals at the moment for beds."
He added: "We're hoping that the staff will stay well and not catch coronavirus because, at the end of the day, we need our staff to be well, fit and healthy."
Dr Alex then showed the various elements of his protective equipment.
He said: "I just trying to show you what we are using to keep safe and protect ourselves.
"We're taking all the measures we need to."
Dr Alex finished with a message to the public who are being asked to stay at home after a partial lockdown announced by the prime minister on Monday.
Dr Alex said: “We’re asking people at home to follow the same measures. Stay safe, stay at home so we don’t pass on and continue the spread of the virus.”
Coronavirus: Everything you need to know