Two new viruses, previously unknown in the wild have been reported. These are Winword.concept and Rainbow. Many users and anti-virus experts are openly grumbling about the complacency of both IBM and Microsoft in the face of the threat from new viruses. Microsoft's Irish CD pressing plant engineers were in London to look at the latest anti-virus software but had not yet reached a decision to buy. Microsoft and IBM's own anti-virus products are not held in particularly high regard by specialists. The Virus Bulletin tested Microsoft's DOS Anti-Virus and it detected only 52.5% of all viruses and just 7% of polymorphic viruses. Although the detection rate of IBM's Antivirus was 99.4% overall and 86.2% for polymorphic viruses, it was one of the slowest products tested.To be really effective anti-virus software should be updated as often as every month. The anti-virus industry is looking at two methods of detecting Winword.concept. The first is called point scanning and involves looking for small pieces of mischievous code, such as the instruction format disk . The second is called grunt scanning and involves scanning all data files.