patient zero

noun

plural patient zeros also patient zeroes
: a person identified as the first to become infected with an illness or disease in an outbreak
The quest to find patient zero, the first person to contract the new virus, has revealed the first known case occurred in Wuhan …Susan Dunlevy
especially : a person documented as being the first known case of a communicable disease in a particular population or region
Stay out of hospital emergency rooms unless you are severely ill or injured. For now, it's the likeliest place to catch coronavirus. Anyone unknowingly suffering from coronavirus is likely to go there. That's what "patient zero" in Italy did. Betsy McCaughey
The 26-year-old nurse contracted Ebola after volunteering to care for U.S. 'patient zero' Thomas Eric Duncan, who tragically died on October 10 from the deadly disease. Ashley Collman et al.
compare index case sense 2

Examples of patient zero in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
So, naturally, when one of Jacob’s students becomes patient zero of a ringworm outbreak at Abbott, the touchy-feely bubble of the early stage of Gregory’s relationship with Janine quickly bursts, becoming their first real speed bump since going public. Ile-Ife Okantah, Vulture, 16 Oct. 2024 Where to watch Black Mirror: Netflix 02 of 21 Broadchurch (2013–2017) Olivia Colman and David Tennant star as dower detectives investigating the murder of a young boy in this British series, which is essentially patient zero for every crime-busting Britbox show from the last decade. Declan Gallagher, EW.com, 29 Sep. 2024 Steven Soderbergh's thriller follows the quick spread of a virus that turns into a disruptive global pandemic (sound familiar?) starring Gwyneth Paltrow as the patient zero, Matt Damon as her husband, Jude Law as a conspiracy theorist and Laurence Fishburne as a Fauci-esque physician. 8. Brian Truitt, USA TODAY, 19 July 2024 This suggests the possibility that this worm might have originated from multiple patient zeros in different countries. Dan Goodin, Ars Technica, 25 Apr. 2024 McConaughey appears to be patient zero for testing the theory while living in the middle of the United States. Nardine Saad, Los Angeles Times, 8 Mar. 2024 That could change if the lone mule deer that tested positive in Yellowstone National Park in November becomes patient zero in a local outbreak. Katie Hill, Outdoor Life, 4 Jan. 2024 The patient zero for the latest outbreak of the Ebola virus is believed to have been a person in a remote, mountainous area in southern Guinea, a country with just one doctor per 10,000 people. Jessica Hatcher, Foreign Affairs, 28 Apr. 2014 The major concern with these coronavirus clusters is that the patient zero spreads the illness beyond their household and inner circle and into the community. Selena Randhawa, refinery29.com, 20 Oct. 2020

Word History

First Known Use

1987, in the meaning defined above

Time Traveler
The first known use of patient zero was in 1987

Dictionary Entries Near patient zero

Cite this Entry

“Patient zero.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/patient%20zero. Accessed 15 Nov. 2024.

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