The number of new Aids cases recorded in Switzerland last year rose to 300 – the second consecutive increase.
The Federal Health Office said on Monday that it expected the figure to continue to grow in the future.
Statistics show that 203 men and 97 women developed Aids last year – up just over six per cent on the previous year.
Officials said the figure included 176 cases diagnosed prior to 2004 but only reported to the authorities between January and December last year.
The past two years have seen a reversal of a downward trend which started in the mid-1990s.
In 1995 there were a record 735 new Aids cases, but this figure fell to a low of 199 in 2002.
“[Data shows] that for some time the number of actual cases is probably rising again,” said the Federal Health Office in its statement.
It said that one possible reason for this was that some patients were developing resistance to antiretroviral combination therapies used in the treatment of the disease.
Statistics show that there were 58 Aids-related deaths in Switzerland last year, of which 43 were men.
In 2003 the overall total stood at 90, but officials said that figures for the past few years were still only partial.
For the second successive year, heterosexual relationships accounted for the bulk of new HIV infections – 42 per cent for men and 87 per cent for women.
Among men, homosexual relationships came second (37 per cent), with intravenous drug use blamed for 15 per cent of infections. Seven per cent of women contracted the disease through drug use.
swissinfo with agencies
New Aids cases:
2004 - 300
2003 - 282
2002 - 199
2004 - 58
2003 - 90
2002 - 96.
Acquired Immune Deficiency Syndrome (Aids) is caused by the Human Immunodeficiency Virus (HIV).
HIV damages the immune system and makes it harder for the body to fight off infections. It is mainly transmitted through body fluids.
Medication exists that slows down the development of HIV into Aids. But as yet there is no cure for Aids.
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