Quarantine
Quarantine is the practice of isolating individuals, places, or things that carry a potentially dangerous ailment. 

In 2268,  suggested that the Federation would quarantine the area surrounding the planet Scalos in order to keep other starships from falling prey to their trap. ()

As of 2269, the planet Vendor was placed under quarantine by the Federation. () 

Captain Jean-Luc Picard placed Vagra II under quarantine in 2364 after the entity Armus killed Tasha Yar and sought a way off the planet. ()

Dr. Katherine Pulaski recommended a quarantine of the  after the entire crew died from rapid aging caused by genetically-engineered children at the Darwin Genetic Research Station in 2365. 

As part of the quarantine, red flashing beacons on the hull of the ship where turned on and the following message was repeatedly broadcast on all frequencies:

"Extreme caution! The USS Lantree is a quarantined vessel by order of Starfleet Command. Do not board!"
 {The ship was later destroyed}

Pulaski later recommended a quarantine of the research station as well. ()

When Willie Potts was tricked into hiding due to his brother, Jake Potts, on Ogus II in 2367, Willie accidentally ingested parasites from a cove palm. In order to get medical assistance at Starbase 416, Willie had to be placed in quarantine. ()

In 2369 after several crewmembers including Miles O'Brien and Jadzia Dax suffered from the aphasia virus, Benjamin Sisko told Doctor Bashir that he wanted DS9 under emergency quarantine. ()

In 2373, an Antidean transport's cargo was being held in quarantine aboard Deep Space 9. Doctor Julian Bashir was required to issue a health certificate to remove it. ()

Quarantine technologies
Isolation ward
Quarantine chamber
Quarantine field
Quarantine pod
Quarantine transmitter
Styrolite

External link
 

de:Quarantäne
Medical procedures