The prevalence and genotypic analysis of Toxoplasma gondii from individuals in Scotland, 2006-2012.
Contemporary information relating to the prevalence of Toxoplasma gondii in humans is lacking for the UK population, with even less information available about the human prevalence of the parasite in Scotland. To address this, two different study groups were used to determine the prevalence and genotypes of Toxoplasma gondii in the Scottish population.



The first study group included serum samples from blood donors (n = 3273) over a four-year period (2006-2009) and the second study group comprised of DNA samples extracted from human brains (n = 151) over a five-year period (2008-2012). A T. gondii IgG ELISA was performed to determine seroprevalence and available sera from individuals who had seroconverted were tested by TgERP ELISA (sporozoite specific antigen). Human brain DNA was tested for T. gondii by ITS1 PCR and positives genotyped at the SAG3 and GRA6 loci by PCR-RFLP analysis.



Seroprevalence to T. gondii from blood donors was found to be 13.2 % (95 % CI: 11.5-15.1 %). Evidence of seroconversion (n = 2) as well as reversion to sero-negative status (n = 6) was evident from blood donors who had donated within all four collection periods (n = 184). The TgERP ELISA (indicating oocyst infection) was positive for one individual. The molecular detection of T. gondii DNA from human brains indicated a prevalence of 17.9 % (95 % CI: 12.1-24.9 %), with genotyping identifying alleles for types I and III. An increase in age was associated with an increase in detection of the parasite within both study groups.



Our research provides current figures for the prevalence of T. gondii in Scotland and also shows evidence of seroreversion within the cohort of blood donors. In both study groups there was a correlation between increasing age and an increase in T. gondii prevalence, indicating that acquired infection plays an important role within the Scottish population.
Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland.
Alison
A
Burrells
National Institute for Public Health and the Environment (RIVM), Centre for Infectious Disease Control, Bilthoven, The Netherlands.
Marieke
M
Opsteegh
Health Protection Scotland, National Services Scotland, Meridian Court, Glasgow, Scotland.
Kevin G
KG
Pollock
Scottish Parasite Diagnostic and Reference Laboratory, Glasgow Royal Infirmary, Glasgow, Scotland.
Claire L
CL
Alexander
Scottish Toxoplasma Reference Laboratory, Microbiology Department, Raigmore Hospital, Inverness, Scotland.
Jean
J
Chatterton
Scottish Toxoplasma Reference Laboratory, Microbiology Department, Raigmore Hospital, Inverness, Scotland.
Roger
R
Evans
Quintiles, Almondvale Way, Livingston, West Lothian, Scotland.
Robert
R
Walker
Sudden Death Brain Bank, Department of Pathology (Neuropathology) Wilkie Building Teviot Place, University of Edinburgh, Edinburgh, Scotland.
Chris-Anne
CA
McKenzie
USDA ARS, Northeast Area, Animal Parasitic Diseases Laboratory, Beltsville, Maryland, USA.
Dolores
D
Hill
Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland.
Elisabeth A
EA
Innes
Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland. frank.katzer@moredun.ac.uk.
Frank
F
Katzer
D000293:Adolescent; D000328:Adult; D000368:Aged; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000235:genetics / Q000378:metabolism; D001782:Blood Donors; D001921:Brain / Q000469:parasitology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation; D005838:Genotype; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D015995:Prevalence; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D012606:Scotland / Q000453:epidemiology; D016036:Seroepidemiologic Studies; D014122:Toxoplasma / Q000235:genetics*; D014123:Toxoplasmosis / Q000453:epidemiology* / Q000469:parasitology; D055815:Young Adult
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C095047:GRA6 protein, Toxoplasma gondii; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; C087692:SAG3 protein, Toxoplasma gondii
Blood donors; Genotyping; Human brains; Longitudinal study; Serology; Seroprevalence; Seroreversion; Toxoplasma gondii