To lessen the threat of spreading the coronavirus designers are creating door-handle adapters that remove the need for direct contact. Here are five of the most interesting door-handle hacks.

Hands-free door knob by Adapta

Design studio Adapta has created a device that allows people to open common round door knobs using an arm or elbow. The attachment fits directly onto circular handles that are normally almost impossible to open without gripping.

As an additional level of security the device is printed from thermochromic pigments so it temporarily changes colour when someone touches it with their hands.

Handy by Matteo Zallio

Matteo Zallio, a designer and visiting postdoctoral scholar at Stanford University, has created a 3D-printed tool that can be used for numerous tasks that would normally require touching a surface directly. Its pair of hooks can be used for opening doors.

"Having a personal multipurpose tool to avoid direct contact with handles, buttons, bags and other daily objects outside of our home, helps to increase hygiene and to lower chances of getting infected," Zallio said.

3D-printed door openers by Materialise

Belgium-based Materialise has created a 3D-printed device that can be attached to door handles to allow them to be opened using an arm. The company has made the printable design available for free.

"The power of 3D printing in combination with Materialise's three decades of 3D printing expertise made it possible to turn an idea into an innovative product in less than 24 hours," said Fried Vancraen, CEO of Materialise.

Forearm shield by FSB

Door handle manufacturer FSB has created a forearm shield that can be attached to the majority of commonly stocked lever handles.

According to the brand the adaptor can be fitted to either angular or circular handles that have a diameter of between 18 and 25 millimetres.

Cable tie attachment by Ivo Tedbury and Freddie Hong

Architectural designers Ivo Tedbury and Freddie Hong have created a 3D-printed device that can be cable tied to "fire escape-style" pull door handles.

"I live in a block of flats and was frustrated at the number of shared doors between my flat and the outside world," Tedbury told Dezeen. "If you're going out to buy groceries, you might end up with contaminated hands within 30 seconds."