The U.S. economy might be humming along right now, but you should be prepared in case that changes. Job seekers hoping to insulate their careers from a downturn should opt for expanding industries and specialized tasks that can't be done by a robot or are less likely to be outsourced to another country.

Here are five industries that fit that bill:

Information security

Within the information technology sector, information security analysts are among the most in demand as the number of cyberattacks on computer networks and systems increases. Data from the U.S. Bureau of Labor Statistics predicted an increase by 18 percent, or 14,800 jobs, between 2014 and 2024. In light of this trend, colleges are implementing dedicated information security programs.

Health care and surgery

A growing number of health care providers and their clients might be trying out telemedicine or conducting robotic surgery, but some procedures and calls can't be handled solely through such tools. "Even with the automation of some functions in the medical field, nothing can replace a real person taking care of you," said Cheryl Palmer of the career coaching firm Call to Career. Doctors' education typically includes an undergraduate degree, a medical degree, and often three to seven years in internships and residencies, depending on the specialty. Primary care physicians received a median annual compensation of $241,273, according to the Medical Group Management Association's Physician Compensation and Production Survey, published in 2015.

Occupational therapy

Those who don't want to spend as much time in school could opt to become occupational therapy assistants, one of more than a half-dozen health care industry jobs on the BLS list of fastest growing careers. The median annual wage for OT assistants was $59,010 in May 2016, according to BLS figures. If you want to be an occupational therapy assistant, you need an associate degree from an accredited occupational therapy assistant program and a professional license in most states.

Automotive service

An economic downturn could actually boost job security for mechanics and other auto repair specialists as drivers look to keep cars running longer. Most technicians need to complete postsecondary education programs and earn certifications in their field to land entry-level jobs. They must also be more computer-savvy than mechanics of a generation ago. Automotive technicians have one of the highest rates of injuries and illnesses of all occupations, according to the BLS. The median annual wage for automotive service technicians and mechanics was $38,470 in May 2016.

Accounting and auditing

Certain types of financial services professionals are always in demand. After all, keeping close tabs on company cash flow can be even more crucial during a downturn, which means tax accountants, forensic accountants, auditors and those with similar titles are fairly insulated during recessions. These professions typically require at least a bachelor's degree in accounting or a related field. Accountants and auditors earned a median annual salary of $68,150 as of May 2016, according to the BLS.