Four UK health workers have died after being injured with needles used on patients infected with HIV, according to official figures.
Needlestick injuries remain common
Another nine are living with HIV after suffering similar "needle-stick" injuries while working in the NHS.
There are hundreds of reported incidents each year in which NHS staff are exposed to a risk of HIV or hepatitis infection.
The Royal College of Nursing says that more protection measures are needed.
The figures formed part of a report on needle-stick injuries written by the Health Protection Agency and passed to the House of Commons Public Accounts Committee.
The agency found five cases in which HIV was definitely passed this way - four of whom are now dead.
Two were nurses who pricked themselves on needles taken from HIV patients.
Since 1997, despite more than 1,600 cases in which staff reported similar exposure to either HIV or hepatitis B or C, there have been no reported cases in which HIV developed as a result.
This is partly due to better availability of powerful drug treatments which, if taken as soon as possible after exposure to HIV, may be able to stop the virus becoming established.
However, Sheelagh Brewer, an employment relations adviser at the Royal College of Nursing, said that the problem of needle-stick injuries remained a major issue.
She said: "A large proportion who report exposure to HIV in this way are nurses, which is why we have an interest in the subject.
"It is possible to improve safety - staff can be trained on the correct way to deal with sharp needles.
"In some cases, needles are simply left lying on beds or not put away into the correct containers.
"We would also like hospitals to consider safer needles, such as retractable needles, or self-blunting needles."
This is supported by HIV charity the Terrence Higgins Trust.
Spokesman Lisa Power said: ""We support the use of retractable needles and any other measures to improve the safety of injecting equipment.
"However, the healthworkers who died contracted the virus before the availability of post-exposure prophylaxis or PEP to NHS staff.
"PEP is a short course of anti-retroviral treatment which can prevent HIV from taking hold in someone who knows they have been very recently exposed."
The Public Accounts Committee is continuing an investigation into the costs to the NHS of needle-stick injuries.
Conservative committee member Richard Bacon MP said: "The figures for needlestick injuries are stupendously high.
"One in three nurses has had such an injury.
"Safer needles need to be used as much as possible."
At present, there are no plans to offer HIV or hepatitis testing to the majority of healthcare workers to identify those who do not know they have been infected.
The RCN is opposed to widespread testing, as it says it would stigmatise those already living with HIV whose infection did not impact on their ability to care for patients.