Toxoplasmosis–Schizophrenia Research

(last updated July 2011)

Welcome to the Toxoplasmosis–Schizophrenia Research section. This site is maintained by the Stanley Medical Research Institute (SMRI) and the Stanley Division of Developmental Neurovirology for SMRI-funded researchers and others interested in the possible etiological relationship between Toxoplasma gondii (and related organisms) and schizophrenia (and related psychoses). The purpose of the webpage is to make information on this line of research, including background data and current research, easily available.

This section will be updated periodically. Comments, suggestions, additions, and corrections are welcomed. They can be sent to either E. Fuller Torrey, MD, or Robert H. Yolken, MD.

Related sites:

www.toxodb.org/toxo: provides detailed information on the genome of Toxoplasma gondii

http://www.schizophreniaforum.org/: a useful online forum to keep updated on schizophrenia research

TABLE OF CONTENTS

Introduction

            I.    All about Cats and T. gondii Transmission

          II.    Possible Transmission of T. gondii from Cats to Humans, Causing Schizophrenia

        III.    Epidemiological Similarities and Differences between Toxoplasmosis and Schizophrenia

        IV.    Effects of T. gondii on Behavior and Psychiatric Symptoms

          V.    Studies of T. gondii Antibodies in Schizophrenia

        VI.    Neurotransmitters and T. gondii

      VII.    Neuropathology of T. gondii

    VIII.    Treatment Approaches to Toxoplasmosis and Schizophrenia

Introduction

SMRI has undertaken extensive research on infectious agents as one of the possible causes of schizophrenia. Among the infectious agents that appear most promising is Toxoplasma gondii, a protozoan parasite that causes toxoplasmosis and is carried by cats and other felines. Until recently, toxoplasmosis was thought to be a problem only for pregnant women who, if they became infected with T. gondii during their pregnancy, risked having the organism cause damage to the growing fetus. This is why pregnant women are advised to not change the litter in the cat litter box. Infection with T. gondii in other adults and children was thought to be either asymptomatic or to cause an influenza-like or mononucleosis-like syndrome. It now seems possible that T. gondii may be associated with schizophrenia and perhaps other psychiatric syndromes.

Schizophrenia is a brain disease that begins in young adults, typically between the ages of 16 and 30, and is characterized by some combination of auditory hallucinations (hearing voices), delusions, flattened affect, disordered thought patterns, bizarre behavior, and social withdrawal. Schizophrenia affects approximately 1 percent of the adult population and in most cases is a lifelong disease with remissions and exacerbations. It is also a very expensive disease. Conservative estimates place the cost of schizophrenia in the United States at more than $40 billion a year.

For additional information on schizophrenia, see Torrey EF, Surviving Schizophrenia, 5th edition (New York, HarperCollins, 2006) and the following websites:

http://www.schizophrenia.com/

http://www.mentalhealth.com/