NEW YORK — There’s little wonder why George Orwell’s novel “1984” is seeing a resurgence in sales.

More than half of Americans polled in a survey released Thursday said they agreed with the statement “We are really in the era of Big Brother.”

The survey from the University of Southern California was conducted last year, before recent revelations of large-scale, secret government surveillance programs. Yet it still found that some 35 percent of respondents agreed that “There is no privacy, get over it.”

A growing number of Internet users said they are concerned about the government checking on their online activities, according to the survey. But even more people were worried about businesses doing the same.

The USC Annenberg School’s Center for the Digital Future has polled more than 2,000 U.S. households about their Internet and technology use each year, with the exception of 2011, since 1999.

Forty-three percent of Internet users said they are concerned about the government checking what they do online, up from 38 percent in 2010. But 57 percent said they were worried about private companies doing the same thing — up from 48 percent in the earlier study.

A 2012 survey by the Pew Research Center found that almost three-quarters of Americans are concerned that businesses are collecting too much information about people like them, while 64 percent had the same worry about the government.

In addition to their views on privacy, the most recent report also found that 86 percent of Americans are online, up from 82 percent in 2010. That’s the highest level in the study’s history and further evidence of how central the Internet has become in American’s lives, especially in the age of mobile devices.

“We find that people almost never lose their mobile phone,” said Jeff Cole, author of the study and director of the center. “They can drop it in the gutter, have it stolen but leave it on the table at a restaurant — most of us don’t even get through the front door before noticing it.”

More than half of the Internet users surveyed said they go online using a mobile device, up from a third who said the same thing in 2010. As expected, texting is becoming increasingly important for people of all ages — 82 percent of mobile phone users text, up from 62 percent in 2010 and 31 percent in 2007.

Among other key findings:

* Thirty percent of parents said they don’t monitor what their children do on social networking sites such as Facebook, while 70 percent said that they do.

* Nearly half of parents, 46 percent, said that they have their kids’ passwords so they can access their account.

* People spent more time online than in any previous year of the study. On average, they were online 20.4 hours per week, up from 18.3 hours in 2010 and about nine hours in 2000.

* One percent of respondents said they visit websites with sexual content “several times a day,” while 69 percent said they never do.

* Dial-up is going the way of the dodo: 83 percent said they access the Internet using a broadband connection, up from 10 percent in 2000.

* The line between work and home life is blurring. Nearly a quarter of Internet users said they “often” use the Internet at home for work-related purposes. Conversely, 18 percent said they “often” go online at work for non-work related activities. The study did not say whether these were the same people.

The 2012 poll had a margin of error of plus or minus 2.7 percentage points. And about that “1984” sales surge — the book has been steadily climbing up Amazon’s list of “movers and shakers” books, the online list of the biggest sales gainers over the previous 24 hours. As of Thursday afternoon, the 60th anniversary edition of the classic was No. 6 on the list, with sales up threefold in the previous day.