The Royal College of Nursing has criticised the government for planning to revise admission procedures for foreign trainee nurses after a health authority said some African trainees were HIV positive.

The Department of Health stressed there was no risk to the public from Wolverhampton's decision to employ five to 10 men and women nurses infected with HIV. But a spokesman suggested tests for HIV should come at the earliest possible stage of the admission process.

The Royal College of Nursing said the government was treading difficult ground as it was illegal in Britain to test for HIV unless an individual consented.

The trainees, from sub-Saharan Africa, including Zimbabwe, are working at the city's New Cross hospital or completing a three-year nursing course at Wolverhampton University. After training they will work in British hospitals and are not obliged to tell patients or colleagues they have the virus.

Jane Eminson, chief executive of Wolverhampton health authority, said the nurses conformed to NHS guidelines on the employment of HIV staff, and were part of a number of NHS staff with the virus across Britain. They did not take part in procedures where there was a risk of patient tissue being exposed to their blood.

Ms Eminson said Wolverhampton's intake of HIV positive nurses from Africa had increased in the past three months.

A Department of Health spokeswoman said: "We must be clear that this is not part of the NHS's international recruitment campaign. The NHS is not actively recruiting from developing countries such as Zimbabwe."

She added: "It is unusual to have such a group of HIV positive students from one country at one school of nursing, and the government will be reviewing the way in which nursing schools admit overseas student nurses."

The spokeswoman said trainee nurses from countries with a high prevalence of tuberculosis were screened for TB in a test which indicated whether they should also be screened for HIV. The department suggested HIV tests should come at the earliest stage.

A RCN spokeswoman said: "Foreign trainee nurses receive the same occupational health testing as UK trainees and we would like to see that continued. If admission procedures for foreign trainees are reviewed, we would want to know why one set of standards is being set for foreign trainees and another for British."

Derek Bodell, chief executive of the National Aids Trust, said: "Given everything we know about how difficult it is for HIV to be transmitted, the public does not have a right to know if someone is HIV positive except under the most unusual circumstances."