England's former chief nurse says nurses have borne the brunt of the pandemic, with staff shortages and difficulty obtaining protective equipment.
Dame Ruth May told the Covid inquiry the NHS was understaffed in 2020, partly due to the "disastrous decision" in 2015 to cut financial support for student nurses.
She said resources were already "stretched", particularly in critical care, which had a knock-on effect on the care some COVID-19 patients received.
She noted widespread reports of personal protective equipment (PPE) supply issues in March 2020, including shortages of plastic gowns that left frontline nurses living in "fear".
Dame Ruth, who served as England's chief nurse from 2019 to July 2024, was one of the senior figures to attend Downing Street press conferences during the pandemic.
The inquest heard she also volunteered for nursing shifts during the coronavirus pandemic, sometimes working "under the radar" on hospital wards.
"In the early stages of the pandemic, we were faced with some extremely difficult decisions," she said.
"This is a rapidly changing environment - we're seeing (a large number of) cases and deaths that we've never seen before."
Dame Ruth said there were around 40,000 nursing and midwifery vacancies in the NHS at the time of the outbreak.
She criticized a "disastrous decision" in 2015 to replace bursaries or bursaries paid to student midwives and nurses with loans.
Dame Ruth said this would result in around 5,700 fewer cadets in England in 2020, which "would have had an impact on the pandemic".
"Burnout will be reduced and the psychological impact will be reduced," she said.
Intensive care units are under huge pressure during the coronavirus pandemic, with specialist intensive care nurses responsible for up to six patients each, rather than the usual one-to-one ratio.
Mrs Ruth admitted it was affecting the care patients received, saying: "It's not where we want to be... I know there are consequences as a result of this."
She told the inquest that blanket do-not-resuscitate orders appeared to have been added to some patients' records because of their age or pre-existing conditions such as autism or learning disabilities, which was "completely false".
Dame Ruth also said it was wrong for some hospitals to prevent pregnant women from being accompanied by their partners during scans or early in labor.
She said a faster rollout of coronavirus testing would allow visitors to return to hospitals earlier and be safer for staff and patients.
Dame Ruth also spoke of the "terrible" online abuse she faced at the time.
"One of the things I learned throughout (the period) was the importance of integrity - and sometimes that comes at a cost," she said.
"That means, especially on social media, you can be vilified - (but) I'm not the only one."
The Covid inquiry is currently gathering evidence on the impact on the NHS and healthcare systems in all four countries of the UK.
More than 50 witnesses are expected to appear in the third part, or "module," which will run until the end of November.