Infections and Psychiatric Diseases
Lecture Outline
Clinical and Epidemiologic Features of
Schizophrenia and Bipolar Disorder
 Biology of Endogenous Retroviruses
 Role of Herpesviruses in Retroviral
Transcription
 Clinical Epidemiology of Herpesvirus
Infections and Psychiatric Diseases
 Clinical Trials of Antimicrobial Agents

Schizophrenia and the Clinical Laboratory
Opportunities and Challenges
Opportunities
Common Disease (1% of American Population)
Availability of more easily tolerated medications
Challenges
Rudimentary knowledge of disease pathogenesis
No relevant animal models or cell lines
No laboratory tests
Minimal prediction of response to medication
Schizophrenia and Bipolar Disorder
Clinical Features
 Schizophrenia
 Positive Symptoms
 Hallucinations, Delusions, Disordered Thinking
 Negative Symptoms
 Withdrawal, Amotivation, Restricted Expressiveness
 Impairment in Cognitive and Social Functioning
 Lifetime prevalence ~ 1% worldwide
 Bipolar Disorder
 Mania
 Depression
 Variable degree of positive and negative symptoms
 Variable degree of cognitive impairment
 Lifetime prevalence ~0.5% worldwide
A Beautiful Mind
Hollywood or Reality
A Beautiful Mind
Hollywood vs Reality?
Reality
Onset of schizophrenia without clear cause
Attractiveness of delusions
Role of medication
Disease “burn out” at later age
Hollywood
Delusions coinciding with creativity
 Shock therapy used at “high class” hospital
Family support
Schizophrenia and Bipolar Disorder
Biological and Epidemiological Features
 Lifelong illness with peak onset in early adulthood.
 Range of structural and functional brain
abnormalities visible on fMRI and PET scans.
 Abnormal expression of brain receptors
Dopamine
Glutamate
 Massive social and economic consequences
 Available medications
Control symptoms in many patients
Have a high rate of side effects
Do not appreciably alter the course of disease
Microbial Agents and Schizophrenia
Epidemiological Findings
 Specific Infectious Agent
 Perinatal Rubella (Brown et al, 2001; OR~3.5)
 Neonatal Enterovirus (Jones et al, 1998 OR~4)
 Maternal Herpesvirus (Buka 2001; OR~4)
 Possible Infectious Exposure
 Seasonality of Birth (Torrey at al, 1998; OR~2)
 Urban Birth (Mortenson et at, 1999, OR~2.5)
 Fever in Pregnancy (Torrey et al 2000, OR~3)
 Pre-eclampsia ( Dalman et al, 1999, OR~2.5)
 Case Reports
 HIV
 Herpes Simplex Virus 1/2
 Toxoplasma gondii
Genetics Of Schizophrenia and Bipolar Disorder
• Increased Incidence in Biological First Degree Relatives
• General Population  1%
• First Degree Relatives 7-9%
• Monozygotic Twins  30%
• Most individuals with schizophrenia do not have a first
degree relative with this disease.
• Genetic factors have a large relative risk but a small risk in
the overall population (5%)
• Intensive search for genes using molecular methods
• Multiple chromosomal regions of linkage
• Single nucleotide polymorphisms of minor effect in
selected populations (OR~2)
• No genes of major effect in different populations
Complex Human Diseases
Beyond Koch and Mendel
Mendel-Human traits are determined
by individual
genes which function independently of
other genes and of environmental
influences
Koch-Many human diseases are
caused by microbes which exert
their effect independently of other
microbes, environmental factors and
genes
Microbial Agents and Human Disease
Koch’s Postulates
Principles
Specific infectious agents cause clearly delineated
disease states
The diseases cannot exist without the specific agent
Etiologic agents cause disease in animal models
Limitations
Shared pathways of response to infection
Genetic determinants of response
Individual variation in response to infection
Limited animal models of complex human diseases
Complex Human Diseases
Beyond Koch’s Postulates
 Most common human diseases are caused by the
interaction of environmental insults and susceptibility
genes.
 Many of the susceptibility genes are diverse
determinants of human response to environmental
factors to infection.
 Informative laboratory methods for complex disorders
have to address both genetic and environmental factors.
 Prevention or treatment of the infections may result in
the effective treatment of complex disorders:
Helicobacter-Peptic Ulcer
HPV-Genital Cancer
Chlamydia-Cardiac Disease?
Etiology of Complex Human Diseases
Relative vs. Attributable Risk
 Relative Risk-Chance of an individual with an exposure
acquiring a disease relative to the general population
 Population Attributable Risk-Percentage of the population
with a disease which can be attributed to a specific factor
 Diseases of single or limited etiologies-High relative and
attributable risks
 CFTR gene-Cystic Fibrosis
 HIV-Acquired Immunodeficiency Syndrome
 Complex Human Diseases Factors with high relative risk
may have low attributable risks if exposures are rare
 Apoliprotein genes-Alzheimer’s Disease
 Maternal alcohol-Fetal malformations
 M tuberculosis-Lung Disease
Epidemiology of Schizophrenia
Relative vs. Attributable Risk
Factor
Relative Risk
Affected Father
7.2
Affected Mother
9.3
Affected Sibling
7.0
Urban Birth
2.4
Winter Birth
1.1
No Factor
1.0
Mortenson et al, NEJM 340:603, 1999
Epidemiology of Schizophrenia
Relative vs. Attributable Risk
Factor
Relative Risk
Affected Father
7.2
Affected Mother
9.3
(No affected parent)
Affected Sibling
7.0
(No affected sibling)
Urban Birth
2.4
Winter Birth
1.1
Mortenson et al, NEJM 340:603, 1999
% Cases In Population
1.2%
2.4%
88.8%
2.2%
97.8%
32.9%
25%
Epidemiology of Schizophrenia
Relative vs. Attributable Risk
Risk Factor
Population Attributable Risk
Affected Parent
3.8%
Affected Sibling
1.9%
Affected Parent or Sibling
5.5%
Place of Birth
34.6%
Season of Birth
10.5%
Place and Season of Birth
41.4%
All Variables
46.6%
Mortenson et al, NEJM 340:603, 1999
Schizophrenia
Working Hypotheses
Most cases of schizophrenia are the result of
infections and other environmental insults occurring
in genetically susceptible individuals before the onset
of clinically apparent symptoms.
 Distinct gene-environmental interactions may be
operant in different populations.
 Interactions do not follow Koch’s postulates.
 The role of specific infectious agents can be defined
by clinical trials of anti-microbial chemotherapy.

Identification of Infections in Schizophrenia
Methods-Old and New

Analytic Methods
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Differential Display PCR
Library screening
Microarrays
Two-dimensional electrophoresis
Enzyme immunoassays
Samples for Analysis

Brains collected by the Stanley Neuropathology
Consortium
 Cerebrospinal fluids (CSF’s) from individuals with
recent onset schizophrenia
 Blood samples from mothers of infants who
developed schizophrenia in adult life.
Differential Display PCR
Brain from Individual with Schizophrenia (S)
and Unaffected Control(U)
M
S
U
S U S U M
HIV
Human Endogenous
Retrovirus HERV-W
Endogenous Retroviruses
Borderland Between Viruses and Genes

Integrated Genomic Elements with Homology to
Retroviruses Arising from Germ Line Integration
of infectious viruses during evolution
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All Primates
Old World Monkeys
Apes
Humans
Individuals
Endogenous Retroviruses
Borderland Between Viruses and Genes II
Dynamic Effects on Gene Function
 Promoter control of adjacent genes- PLA2; Placental Genes
 Interaction with infectious agents- Herpesviruses, Toxoplasma
 Interaction with soluble mediators-Hormones; Cytokines
 Functionality of viral proteins-Syncytin; amino acid transporters
Role in Human Disease
 Diabetes- Superantigen activation
 Multiple Sclerosis- Glial cell function
 Autoimmune Arthritis- T cell activity
 Pre-Eclampsia- Aberrant Fusion of Trophoblasts
Endogenous Retroviruses
Activation and Transcription
Microbe
DNA
Hormone Mediator
5’LTR Viral Proteins 3’LTR
Endogenous Retroviruses
Borderland Between Viruses and Genes

Integrated Genomic Elements with Homology to
Retroviruses Arising from Germ Line Integration
of infectious viruses during evolution
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All Primates
Old World Monkeys
Apes
Humans
Individuals
K113
Herv-W
Ctr
DNA
Scz
Endogenous Retroviral PCR
CSFs:Schizophrenia and Controls
Herv-W
HERVw
C1
A1
A2
A3
A4
A5
A6
GTTCAGGGATAGCCCCCATCTATTTGGCCAGGCATTAGCCCAAGACTTGAGTCAATTCTCATACCTGGACACTCTTGTCCTTCAG
---------------------------------------------------C--------------------------------------------------------------A---------------------------------------------------TG------------------------------A---------------------------------------------------TG----------------------------------C----------------C--G----------------------------G-----------A----------------------------T----------C--G---------------------------TG-----A------------------------------------------------------------------------------------------T------------CA---TA-------------------C--G---------------------------TG-
Herv-W Envelope
Chromosomal Distribution
Herv-W and Amino Acid Transporters
Lavillette et al, J Virol Jul;76(13):6442-52.
ASCT1 HERV-W Receptor
Brains of Cases and Controls
Contentration of ASCT1 Receptor
Schi zophreni a
5
Bi pol ar Di sorder
Cont rol
P<.02
4
P<.005
3
P<.009
2
1
0
Neuron
Inter-Neuron
Cingulate Gyrus
White M atter
Human Endogenous Retroviruses
Activation by HSV-1Perron et al J Gen Virol. 1993 Jan;74 ( Pt 1):65-72
.
Retrovirus
HSV-1
Reverse Transcriptase
Activity
Cognitive Functioning and Antibodies to Infectious Agents
Individuals with Schizophrenia (N=229)
Antibody Positive
Antibody Negative
Cognitive Score (RBANS Total)
80
**
*
HSV-1
Toxo
75
70
65
60
**p<.00001
*p<.009
CMV
HSV-2
EBV
Infectious Agent (IgG Antibodies)
HHV-6
Cognitive Deficits In Individuals with Schizophrenia
Relationship with Antibodies to HSV-1
HSV-1 Pos
N=101
HSV-1 Neg
N=128
***
Immediate Memory
Concentration
*
Language
Attention
**
*
Delayed Memory
***
RBANS Total
50
*** p<.0001
**p<.001
* p<.009
55
60
65
70
75
80
Score(Mean+/-95% Confidence)
85
90
Cognitive Functioning
Association with HSV-1 Serostatus
HSV-1 Seropositive
HSV-1 Seronegative
1 00
RBANS Total Score
95
90
85
80
75
70
65
60
Schiz ophrenia
N = 2 2 9
P =
r 4 4 .1 %
Bipolar Disorder
N = 1 1 7
P =
r 4 1 .9 %
Control
N = 6 7
P =
r 4 1 .8 %
Cognitive Function in Schizophrenia and Bipolar Disorder
Proportion HSV-1 Seroreactive
HSV-1 Antibodies and Quintile of Total Score
Sc hiz ophre nia
Bipola r Dis orde r
N=2 29
N=1 17
0.8 0
0.7 0
0.6 0
0.5 0
0.4 0
0.3 0
0.2 0
0.1 0
0.00
<2 0 th
2 0 -4 0
4 0 -6 0
6 0 -8 0
P er centile- Total Cognitive S cor e
>8 0 th
Collaborative Perinatal Study
Study Design
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65,000 healthy mothers enrolled from 1957-1964 from
11 geographically diverse sites.
Mothers followed closely during pregnancy.
Neurocognitive and developmental testing during first
7 years of life. Primary outcomes cerebral palsy and
mental retardation.
Serum samples obtained from mothers during
pregnancy and infants at birth (cord).
Offspring identified with psychiatric diseases in 1990’s
and matched to maternal and cord blood serum
specimens.
Unselected offspring evaluated for abnormalities
of pregnancy, birth, and child development.
Schizophrenia in Adult Life
Infection During Fetal Development
6.00
Odds Ratio
4.80
3.60
2.40
1.20
0.00
CMV CMV Rub
IgG IgM IgG
Rub Toxo Toxo HSV1 HSV2 Herv
IgM IgG IgM IgG IgG
W
Effect of HERV-K and HSV-1 on
Eclampsia and Mental Illness
Adju ste d fo r
Rac e,SES
Unadjusted
10
9
Odds Ratio
8
7
6
5
4
3
2
1
0
Herv- K
HSV- 1
HERV- K/ HSV- 1
E clampsia
.
Herv- K
HSV- 1
HERV- K/ HSV- 1
Men t alI ln ess
Effect of Maternal HSV-2 on
Pregnancy and Child Development
Unadjusted
Adjusted for
Race, SES
4.50
Odds Ratio
4.00
3.50
3.00
2.50
2.00
1.50
1.00
0.50
0.00
Abnormal
Speech
Low IQ
Age 7-8
Abnormal
Vision
Any
Fetal Deaths
Complication
Perinatal
Valacyclovir Clinical Trial
Individuals with Schizophrenia
Enrollment of 66 patients with stable
schizophrenia on standard medication given
Valacyclovir 2 gm/day for 16 weeks
 Evaluation by the positive and negative
symptom score (PANSS)
 Change in score correlated with viral antibody
status at start of study

 HSV1/2
 CMV
 Other
herpesviruses
Response to Valacyclovir
HSV-1 Antibody Status
20
P er centage Im pr ovem ent
HSV-1 Seronegative
Percent age Improvement
HSV-1 Seropositive
10
0
-10
2
4
8
12
Week of V alacyclovir
Positive Symptoms
16
20
15
10
5
0
-5
-10
2
4
8
12
W eek of Valacyclovir
Total Symptoms
16
Percentage Improvement
Response to Valacyclovir by CMV Status
20
P<.006
20
10
10
0
0
-10
Percentage Improvement
Negative Scale
Positive Scale
30
2
4
8
12
16
-10
2
4
General Scale
8
16
Total Score
20
20
P<.02
P<.0005
10
10
0
0
-10
12
2
4
8
12
16
CMV Seropositive
-10
2
4
8
12
16
CMV Seronegative
Prevalence of Cytomegalovirus
Populations with Schizophrenia
Cologne-Untreated
Cologne-Recent Onset- Treated
Cologne-Control
Heidelberg-Recent Onset- Treated
Heidelberg-Control
Baltimore-Stable Treated
Baltimore-Control
0
10
20
30
40
50
60
Prevalence (%)
70
80
Effect of Valacyclovir on Schizophrenia
Possible Explanations
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Statistical artifact ?
 p<.0005 with covariance for multiple factors
Placebo effect?
 Improvement only in CMV seropositive subjects
 Improvement persists throughout treatment
Non-viral effect of valacyclovir/acyclovir?
 Effect only in CMV seropositive individuals
The replication of CMV contributes to the
symptoms of schizophrenia in some individuals
 Possible role of an antigenically related herpesvirus?
Valacyclovir Treatment of
Schizophrenia-Planned Trials
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Placebo-control trials using encapsulated
valacyclovir and placebo

Stable patients with schizophrenia
 Recent onset patients with schizophrenia
 Patients with bipolar disorder
 High-risk individuals with prodromal symptoms

Study supported by the Stanley Medical
Research Institute, without support from the
pharmaceutical industry.
Infections and Schizophrenia
Conclusions
 Recent onset schizophrenia is associated with:
Increased transcription of HERV-W
Increased levels of antibodies to CMV
 Past infection with HSV-1 is associated with cognitive
impairment in individuals with stable schizophrenia and
bipolar disorder, but not in unaffected controls.
 Maternal exposure to infectious agents is associated with an
increased rate of schizophrenia in the offspring.
 The administration of valacyclovir can reduce symptoms in
some individuals with stable schizophrenia.
 The continued evaluation of the role of the prevention and
treatment of infection in the management of psychiatric
diseases remains a high priority.
Microbial Agents and Schizophrenia
Acknowledgements
 Johns Hopkins University  Harvard University
 Loraine Brando
 Frances Yee
 Vern Caruthers
 Inna Ruslanova
 Bogdana Krivogorsky
 Stanley Medical
Research Institute
 Michael Knable
 Maree Webster
 Sheppard Pratt Hospital
 John Boronow
 Catherine Stallings
 Steve Buka
 Ming Tsuang
 University of Heidelberg
 Silke Bachmann
 Johannes Schroeder
 Karolinska Institute
 Håkan Karlsson
 University of Cologne
 F Markus Leweke