This is a Gram stain of spinal fluid from a person with meningitis. The rod-like organisms seen in the fluid are Haemophilus influenzae, one of the most common causes of childhood meningitis (prior to the widespread use of the H influenzae vaccine). The large red-colored objects are cells in the spinal fluid. A vaccine to prevent infection by Haemophilus influenzae (type B) is available as one of the routine childhood immunizations (Hib), typically given at 2, 4, and 12 months.
Review Date 12/24/2020
Updated by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA.Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.