Viruses on mobile phones are still rare but nearly three-quarters of mobile phone users in developed countries are worried about security on their handsets, a survey showed on Wednesday.

The poll by IT security specialist McAfee, based on 2,000 people in Britain, the United States and Japan, revealed that only 2.1 percent of respondents had had a virus in their handset.

A total of 11.6 percent said they knew someone who had had a virus, while 86.3 percent of people said they had never heard about anyone with a mobile phone virus.

Nevertheless, 72 percent said they were worried about security, with fears most evident in Japan where 89.1 percent said they were concerned and more people had experience of viruses.

The phone market in Japan is the most developed in the world, where subscribers use their handsets to carry out transactions, email and browse the web far more than in other developed countries.

The poll was released at the Mobile World Congress, one of the mobile phone industry's biggest trade shows which runs until Thursday.

Network operators are hoping that consumers increasingly use their phones to access the Internet, download applications and make transactions, meaning security and protection are set to become big issues for the industry.