Taylor Swift’s latest single, Patient Zero, has her fans coming up with several theories on social media about the identity of the subject.While some fan theories speculate it’s about her ex-boyfriend Joe Alwyn and his recent public display of affection with Sarah Pidgeon, others claim the song refers to her other ex, Joe Jonas, and his now-ex-wife Sophie Turner.Disclaimer: These are personal characterizations by post creators/commenters and do not represent factual findings by the publication.X user @vigilantesht shared a GIF and wrote in the caption:“Streets saying Patient Zero is a Joe diss. She knew to whack him again after that sh*t he pulled on her wedding day.”The netizen was referring to Alwyn being spotted kissing and hanging out with Pidgeon in London in early July, around the time of Taylor Swift and Travis Kelce’s wedding celebrations in New York City. Deuxmoi even published exclusive images of Joe and Sarah. Before that, they were seen on an outing in New York City and were reported to have connected at an “industry event.”Many people joined the conversation and shared similar reactions.“I don't know why I got the feeling that Patient Zero is about a certain J brother and his drama with Sophie,” a fan wrote.“Streets saying Patient Zero is basically a diss track that ‘warns’ Sarah Pidgeon about Joe Alwyn,” another fan commented.“Regarding the social scale thing, it's obvious that it's for Joe,” one netizen added.Others continued to weigh in.“So, my Patient Zero theory is that she wrote this song for Sophie Turner amidst her very public divorce from Joe Jonas. Joe & Taylor were each other’s first public romances, making her ‘patient zero’. She heard the rumors about their breakup & wasn’t surprised when Sophie called,” another user wrote.“Patient zero is about Sophie/Zoe/Dakota, etc. and no particular specific ex; that's why it sounds like it could be any of them. She's saying she went through it all with all her exes but still survived and so will the caller (but Joe/Sophie are the main inspo imo),” a person claimed.Some users even speculated that the song is about Taylor Swift’s other ex, Matty Healy.“Do we think Patient Zero is about Joe or Matty? ‘Cause I think she sounds too mad for it to be about Matty, but it does fit his persona, I guess…” one fan stated.“I can maybe see it, but I doubt it, BUT if it's true, then Patient Zero is DEFINITELY about Matty and not Joe,” another one speculated.Exploring Taylor Swift’s relationships with Joe Jonas, Joe Alwyn, and Matty Healy amid ‘Patient Zero’ speculationTaylor Swift dated Joe Jonas for a few months in 2008. Later, she appeared on The Ellen DeGeneres Show and claimed that he broke up with her over a brief phone call when she was 18.“When I find that person that is right for me, he’ll be wonderful, and when I look at that person, I’m not even gonna be able to remember the boy who broke up with me over the phone in 25 seconds when I was 18,” Swift noted.Subsequently, Jonas defended himself against cheating rumors. In 2019, Taylor returned on Ellen’s show and said it was “too much” of her putting Joe Jonas on “blast.”“That was too much. Yeah, that was too much. I was 18. We laugh about it now. That was mouthy teenage stuff there,” she admitted.In a 2019 appearance on ITV’s Lorraine, Jonas spoke about the drama.“It’s something that I probably was feeling pretty bad about when I was younger, but at the end of the day, I’ve moved on. I’m sure Taylor’s moved on, and it feels nice, and we’re all friends. It’s all good. We were so young.”Four years later on the Armchair Expert podcast, he also said he and Taylor were “cool”, and the speculation surrounding their split was “many, many years removed.” Joe also joked that he hoped that the Swifties do not hold a grudge against him.Over the years, Taylor Swift has reportedly written several songs about Joe Jonas, including Forever & Always, Last Kiss, Mr. Perfectly Fine, and Holy Ground. Jonas also allegedly sang about Swift on the single Much Better.In fact, Joe once briefly dated Taylor’s friend and supermodel Gigi Hadid. Later, he tied the knot and had children with Swift’s other friend and actress Sophie Turner. However, it ended in a divorce in 2024.Now, amid the release of Taylor Swift’s latest song, which has the lyric, “But if you’re sick of him, I got you, I was patient zero,” fans are claiming it’s about Jonas and Turner’s divorce and how Swift seemingly took in Sophie after the split and helped her through it. View this post on Instagram Instagram PostTaylor Swift later had a nearly six-year-long relationship with Joe Alwyn, which ended in early 2023. The following year, Alwyn said in an interview:“I empathize and understand the difficulties that come with the end of a long, loving, fully committed relationship.”Since the split, Taylor Swift has reportedly written songs about Alwyn, including End Game, So Long London, and Paper Rings. Last year, he told The Guardian:“I have tried to just focus on controlling what I can control. I think I've done what lots of people who find themselves in the public eye do, which is just try and ignore it.”Following her breakup with Alwyn, Swift briefly dated Matty Healy in mid-2023. She opened up about the period in her 2025 Disney+ docuseries End of an Era, saying it was a “rough time” as she went through a “lot of breakups.” It is presumed that several songs in her 11th studio album, The Tortured Poets Department, were about Healy, including the title track and The Smallest Man Who Ever Lived.Joe Alwyn is reported to be “casually dating” Sarah Pidgeon. Meanwhile, Matty Healy tied the knot with model-musician Gabbriette Bechtel in July, only two weeks after the Swift-Kelce wedding.Patient Zero is a recent single from Taylor Swift's deluxe reissue of The Life of a Showgirl: The Encore.