The NHS has more than 100,000 vacant posts, Labour has estimated.
The full-time equivalent vacancy rate across England's acute, community and mental health trusts is 9%, Labour's shadow health secretary has said.
This is a rise from 8.4% last year, Jonathan Ashworth, MP for Leicester South, found.
Information obtained by the party from 82 NHS trusts in England found that the average nurse vacancy rate was 12.2%.
After extrapolating the figures, it estimated that the health service across the country has more than 42,000 nursing vacancies.
The total of full-time equivalent vacancies for doctors was 9.3% - equating to more than 11,000 positions across the sector.
"Tory mismanagement of the NHS workforce has been a disaster for staff and patients alike," Mr Ashworth said.
"For years the Government has failed to ensure enough new recruits coming through in key specialities, while failed policy decisions like the NHS pay cap and the ending of the NHS bursary have contributed to a growing crisis.
"What's more, trusts are having to spend £3bn a year on temporary staff to plug the gaps, meaning money that should be going to frontline services is going on agency fees instead.
"There is now an urgent need for a sustainable, fully-funded plan to get the right numbers of staff in place to keep patients safe.
"Labour's research today has shown that NHS workforce shortages in key areas are continuing to get worse year on year - ministers must take action before it's too late."
Last week, Health Education England published a draft health and care workforce strategy that found the NHS in England will need 190,000 more clinical posts over the next 10 years to meet growing demand.
But if supply continues at the rate of the last five years, 72,000 new staff are expected to join the NHS by 2027.
It found that despite an increase in staff in most disciplines since 2012, the health service was still overstretched, partly due to population growth of 2.1 million in the last five years.
The NHS is the largest workforce in the country, making up 13% of all jobs, while 65% of the NHS operational budget is spent on staff.
HEE has now launched a consultation to recruit and retain existing staff in a bid to increase the workforce.
A Department of Health spokeswoman said: "The truth is that latest NHS Digital figures show there are over 32,300 more professionally qualified clinical staff working in the NHS since 2010 and we are increasing training places for doctors and nurses by 25%."
Janet Davies, chief executive and general secretary of the Royal College of Nursing, said: "This analysis pulls back the curtain on the state of staffing in the NHS this winter.
"Despite ministers' rhetoric on the importance of safety, it will enter a perilous January without enough staff to give safe care.
"Nurses are spread too thinly and starting to blow the whistle on falling standards.
"Hospital wards and care homes alike increasingly rely on unregistered healthcare assistants, especially at night.
"The Government must no longer allow nursing on the cheap - patients, particularly vulnerable and older individuals, can pay the highest price.
"The NHS has never been busier and yet it is haemorrhaging experienced nurses quicker than it can find new ones."