She is right on the front lines in the coronavirus fight, as executive director of the National Centre for Infectious Diseases (NCID) - where the bulk of patients are cared for in specially constructed isolation rooms.
This is the sort of pressure Professor Leo Yee Sin, 60, faces: There are at least twice as many patients in the wards than normal, with close to 60 from the current outbreak, and more expected.
She has "to take care of everybody", as she puts it, making sure the infrastructure - only a year old - is able to stand up to the sudden heavy load.
The 330-bed NCID building also houses the National Public Health Laboratory which tests samples from suspect patients for the coronavirus - and from where the confirmation of their illness comes.
Prof Leo now also supports the Ministry of Health as she reports directly to its director of medical services.
Then, there is the pressure of the ever-changing nature of the virus itself. She says: "This outbreak is very challenging. It is not mild and we haven't seen the end yet. The situation is still evolving."
Generally, those who get very sick take a turn for the worse after five to seven days of illness.
A handful of patients with severe conditions have done well and no longer need intensive care.
But she is very worried for one "who has been unable to get himself out of intensive care and still requires mechanical ventilation".
She adds: "I do anticipate that one of these days, we will have a fatal case. What we want to do is to minimise the number (of fatalities) as much as we possibly can."
Her role today is far bigger than during the severe acute respiratory syndrome (Sars) outbreak in 2003. Then, she had just a clinical role caring for patients and advising policymakers on the medical situation.
Compared with Sars, the cases this time are escalating much faster. Because of the quick increase in coronavirus patients and the need to screen many more patients for the disease, she needed to bring in staff from Tan Tock Seng Hospital next door, since even the numbers of buffer staff were not enough.
Says Prof Leo: "We have to come out of our norm, to handle something that is very different. We have adapted a workflow to make sure that we can function, and function safely."
But she adds that many of the doctors and nurses are "old troop" who have handled other outbreaks, like Sars, the Nipah virus and Zika, so their experience is proving very useful.
Still, she says that 24 hours a day is just not enough: "I need at least 28, even 36 hours a day."
What has to give is her sleep and personal life, but that is part of her job and her husband is very understanding, she says, knowing that at times like this, "family becomes secondary". Her three children are grown up.
"The virus doesn't take time off, no weekends or holidays. It is running very fast, so we need to be faster, to be ahead of the curve."
As with Sars, people have been very supportive, she says, offering her staff at NCID free food, drinks, snacks and flowers.
She is also grateful to the 2,000 Grab drivers who have stepped forward with offers to ferry staff to and from the hospital.