A million US victims lost "billions of dollars" to email phishing scams in the past two years, new research has warned.

According to Consumer Reports's latest State of the Net survey, American consumers lost more than $7 billion over the last two years to viruses, spyware, and phishing scams.

Additionally, the survey shows that consumers face a one in four chance of succumbing to an online threat, a number that has slightly decreased since last year.

The number of consumers responding to email phishing scams has remained constant at eight per cent. The research projects that one million US consumers lost billions of dollars over the past two years to such scams.

The study went on to warn that many underage youngsters are at risk on social networks such as MySpace and Facebook. In households surveyed with minors online, 13 per cent of the children registered on MySpace were younger than 14, the minimum age the site officially allows, and three per cent were under 10. And those were just the ones the parents knew about.

Based on the survey, Consumer Reports projects that problems caused by viruses and spyware resulted in damages of at least $5 billion over the past two years.

The poll was conducted by the Consumer Reports National Research Center among a nationally representative sample of more than US 2,000 households with internet access.

Based on survey projections, computer virus infections prompted an estimated 1.8 million households to replace their computers in the past two years and 850,000 households to replace computers due to spyware infections in the past six months.

Additionally, 33 per cent of survey respondents did not use software to block or remove spyware. And the study projects that 3.7 million US households with broadband remain unprotected by a firewall.