The worm has remained at No. 1 for the past four months while NetSky runner-up has been in place for three months.
According to Carole Theriault, an expert at security firm Sophos, although the number of Zafi.B bugs has been declining over the past three months, it is still a risk to beware. Meanwhile, the number of NetSky virus notifications is in fact increasing. Theriault recommends, including the time that the virus does not cause any major headaches on secure sites, but users still need to update their anti-virus tools regularly.
In September, Sophos recorded and processed 1,150 new viruses. The total number of malicious code that the company has blocked so far has reached 95,025. Sophos said that one in every 15 e-mails circulating on the Internet (equivalent to about 6.6% of all e-mails) contained one virus.
"Sadly, old viruses continue to pose a headache for computer users around the world. These programs will only disappear when they stop spreading, "Theriault said. "Concern for enhancing PC protection for infection prevention is the only way to deal with them."
The 10 most dangerous viruses in September 2004 (in parentheses are the reported rates reported by Sophos)
1. Zafi.B (30.5%)
2. NetSky.P (26.7%)
3. NetSky.D (6.12%)
4. NetSky.Z (5.5%)
5. Bagle.AA (3.8%)
6. Mydoom.O (3.6%)
7. NetSky.B (3.5%)
8. NetSky.Q (2.7%)
9. Lovgate.V (2.6%)
10. NetSky.C (2.0%)
Others: 13.0%.
