General Information: This organism is the causative agent of Glasser's disease in swine but is usually found as a commensal organism in the upper respiratory tract. Glasser's disease is responsible for significant losses in swine husbandry. The disease was first noted in 1910 by Glasser and the organism requires factor V (NAD - nicotinamide adenine dinucleotide) growth factor, like H. suis, but not factor X (iron porphyrin) which H. suis requires. Pathogenicity and virulence are often strain specific. Symptoms include fibrinous polyserositis (fibrous inflammation of serous membranes, polyarthritis (inflammation of multiple joints) and meningitis (inflammation of meninges)and pneumonia.