As Branomir (Bronco) Pavlovic completed 20 laps in the pool, it seemed difficult to believe that just six days earlier he battled COVID-19 in hospital.
He said his remarkable recovery was thanks to having his first vaccination and after he tested positive, the anti-viral medication he received while at St George Hospital in Sydney's inner south west.
"I wasn't interested in getting the vaccine originally, but knew I needed it to keep working so I went to get the shot. Now I'm very glad I did," he said.
He was due for this second dose the day after he was diagnosed.
Mr Pavlovic developed chills, a sore throat and a mild cough, but was grateful COVID-19 didn't hit him harder, especially since he is currently undergoing treatment for stage 4 lung cancer.
As a chemotherapy patient, he was instructed to go to hospital if he developed a high temperature.
When his temperature climbed above 38 degrees, He assumed it was a side effect of his cancer treatment. He had no idea he was infected with COVID-19.
"I was a bit worried but I wasn't overly panicked," he said. "I'm a person who handles adversity pretty well and take things for what they are, not what they could be."
Mr Pavlovic was quickly discharged after nine nights in hospital and his condition was monitored at home by the hospital COVID-19 Telehealth Assessment Clinic (CTAC) team until he was cleared.
"I was given a monitor to take home that sits on your finger to check your oxygen levels and heart rate," he said. "The CTAC team called me every day to ask how I was feeling, record my stats and check if I was developing any new symptoms. I was lucky as my condition was fairly stable.
"It was great to be able to complete my isolation at home. Knowing the CTAC team were monitoring me made me feel reassured that I was in good hands."
The day after he was cleared of COVID-19 and out of isolation, he woke at dawn and swam one kilometre.
"I usually swim 1.5 kilometres four to five times a week and wasn't sure how I'd go the first day back, but I was fine," he said.
He still does not know where he contracted the virus, but said all of the people close to him who received two doses of a COVID-19 vaccine had tested negative.
"It's clear to me that the vaccine works and there is definitely protection from being double vaccinated. Now I encourage everyone to get the two shots," he said.
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