United States Court of Appeals for the Fifth Circuit United States Court of Appeals Fifth Circuit

____________ FILED November 16, 2023 No. 22-40728 Lyle W. Cayce ____________ Clerk

Lisa Torrey; Kathryn Kocurek, Individually and on behalf of the Estate of J. David Kocurek, Ph.D.; Amy Hanneken; Jane Powell; Carol Fisch; John Valerio, Individually and as Next Friend of Christopher Valerio; Randy Sykes; Brienna Reed; Rosetta Fuller; Adriana Monteiro Moreira; Jessica McKinnie; Kristine Woodard; Gayle Clarke; Allison Lynn Caruana; Chloe Lohmeyer; Tawnya Dawn Smith, Individually and as Next Friend of Monet Pitre; Mike Peacher, Individually and as Next Friend of Ashleigh Peacher; Alarie Bowerman, Individually and as Next Friend of Elisa Bowerman, Emory Bowerman and Anais Bowerman,

Plaintiffs—Appellants,

versus

Infectious Diseases Society of America,

Defendant—Appellee. ______________________________

Appeal from the United States District Court for the Eastern District of Texas USDC No. 5:17-CV-190 ______________________________

Before Jones, Stewart, and Duncan, Circuit Judges. Stuart Kyle Duncan, Circuit Judge: Case: 22-40728 Document: 00516971426 Page: 2 Date Filed: 11/16/2023

No. 22-40728

A professional society specializing in the study and treatment of infectious diseases published guidelines in a peer-reviewed medical journal for treating Lyme disease. Individuals who claim to suffer from persistent Lyme disease symptoms sued the society, alleging the guidelines harmed them by casting doubt on how chronic Lyme disease should be treated and even whether the condition exists. The district court dismissed the claims because it concluded that the statements at issue were non-actionable medical opinions, not factual assertions that could support a claim for fraudulent or negligent misrepresentation. We AFFIRM. I. A. Plaintiffs are people who claim to suffer from chronic Lyme disease. A person contracts Lyme disease from ticks carrying the bacterium Borrelia burgdorferi. See generally Robert L. Bratton et al., Diagnosis and Treatment of Lyme Disease, 83 Mayo Clinic Proc. 566 (2008). Typical symptoms are fever, headache, swollen joints, fatigue, and rashes. Many patients respond to short-term antibiotics, but some do not. This latter group is said by some to experience “post-Lyme disease syndrome,” “posttreatment chronic Lyme disease,” or “chronic Lyme disease.” The nature of chronic Lyme disease, and how to properly treat the condition, are matters of scientific dispute. Plaintiffs allege that some doctors, accepting the phenomenon’s existence, recommend a holistic approach that may include long-term antibiotics. Others take a different view—like the Defendant here, the Infectious Diseases Society of America (“IDSA”), a professional society of doctors, scientists, and other healthcare professionals. In 2006, IDSA published The Clinical Assessment, Treatment, and Prevention of Lyme Disease, Human Granulocytic Anaplasmosis, and Babesiosis:

2 Case: 22-40728 Docu