Toxoplasmosis of Animals and Humans

J. P. Dubey

• Publisher: CRC Press
• Year: 2021
• ISBN:
  9781000431490
• Edition: 3
• Topic: Ciencias biológicas
• Subtopic: Evolución

This is the only book to cover toxoplasmosis of animals and humans thoroughly in one single source. Found worldwide from Alaska to Australasia, Toxoplasma gondii is the cause of one of the most common parasitic infections in humans, livestock, companion animals, and wildlife, and is included on the list of potential bioterrorism microbes. Furthermore, T. gondii has been and continues to be used extensively as a model for the cell biology of apicomplexan parasites.

In the decade since the second edition of this book was published, there has been an explosion of knowledge concerning the parasite Toxoplasma gondii and toxoplasmosis. This update provides unique information on all known host types for this parasite, with an additional chapter on history, substantial updates throughout, and a detailed focus on the biology of the parasite in Chapter 2. The third edition is compiled by author JP Dubey, an authority on T. gondii who has worked with virtually all hosts of the protozoan during the last 55 years, including humans, all livestock species, wildlife, and zoo animals.

The book distills the voluminous and potentially confusing scientific literature, that has grown geometrically in the 30+ years since the publication of the first edition, into a comprehensive resource for all professionals, graduate students and researchers working in this field.

CHAPTER 1 Introduction and History of Toxoplasma gondii

1.1 Introduction and History

Toxoplasma gondii is one of the most well-studied parasites because of its medical and veterinary importance. It is used extensively as a model for cell biology of apicomplexan organisms. Two recently published books provide an update of its cell biology, molecular biology, and methods to study it.^1228,1311 Some of the advantages of using this parasite for cell biology are as follows: T. gondii is large enough to be easily seen under the light microscope, can be grown in virtually any warm-blooded cell line, can be maintained indefinitely in mice and cell culture, and there is only one species that infects all hosts. Additionally, this parasite is readily amenable to genetic manipulation, with refined protocols for classic and reverse genetics, high transfection efficiency, and expression of epitope tags. Recently a book was published that detailed methods to study its cell biology and genetic manipulation.¹²²⁸ The third edition of the book “Toxoplasma gondii”: The Model Apicomplexan-Perspective and Methods has 1,184 pages contributed by numerous expert in the field.¹³¹¹

It has been more than a century since the discovery of the parasite in 1908 and the event was celebrated with publication of historical accounts of the parasite and its biology.^{394,399,491,911,1310} Historic landmarks are summarized in Table 1.1.

Table 1.1 Summary of Landmarks in the History of T. gondii^a

Finding	Reference
Etiologic Agent
Protozoa found in the rodent, Ctenodactylus gundi in Tunisia	Nicolle and Manceaux (1908)
Protozoa found in a rabbit in Brazil	Splendore (1908)
Name T. gondii proposed (taxon = bow, plasma = form, in Greek)	Nicolle and Manceaux (1909)
First viable T. gondii isolate obtained from an animal	Sabin and Olitsky (1937)
First isolate of T. gondii from human	Wolf et al. (1939)
Human and animal T. gondii proven identical	Sabin (1941)
Pathogenesis of toxoplasmosis, including hydrocephalus	Frenkel and Friedlander (1951); Frenkel (1953, 1956)
Parasite Morphology and Life Cycle
Tachyzoite (trophozoite, feeding form, proliferative form, endodyozoite)
Term tachyzoite proposed (tachy = fast, zoite = life)	Frenkel (1973)
Endodyogeny described	Goldman et al. (1958)
Ultrastructure described	Gustafson et al. (1954); Sheffield and Melton (1968)
Tissue cyst, bradyzoite, cystozoite
Cyst recognized	Levaditi et al. (1928)
Cyst described cytologically	Frenkel and Friedlander (1951); Frenkel (1956)
Ultrastructure described	Wanko et al. (1962); Ferguson and Hutchison (1987)
Term bradyzoite proposed (bradys = slow, zoon = animal)	Frenkel (1973)
Term tissue cyst proposed	Dubey and Beattie (1988)
Bradyzoite resistance to digestive enzymes recognized	Jacobs et al. (1960a)
Development of tissue cysts and bradyzoites described	Dubey and Frenkel (1976)
Complete biology of bradyzoites and tissue cysts reviewed	Dubey et al. (1998)
Feline enteroepithelial stages
Coccidian phases described	Frenkel et al. (1970); Hutchison et al. (1970); Sheffield and Melton (1970); Dubey and Frenkel (1972)
Oocyst morphology described	Dubey et al. (1970b)
Five asexual T. gondii types (A–E) described	Dubey and Frenkel (1972)
Ultrastructure of coccidian stages described	Sheffield (1970); Piekarski et al. (1971); Ferguson et al. (1974, 1975, 1979a, 1979b); Christie et al. (1978); Speer, Clark, and Dubey (1998); Speer and Dubey (2005)
Lipid metabolism determines host specificity of T. gondii oocyst excretion in cats	310
Transmission
Congenital
Transmission demonstrated in human	Wolf et al. (1939)
Repeated transmission found in house mouse	Beverley (1959)
Congenital transmission found in a large wild animal species, white-tailed deer	Dubey et al. (2008)
Carnivorism, transmission by meat of intermediate hosts
Suggested carnivorous transmission	Weinman and Chandler (1954)
Transmission by meat found in humans	Desmonts et al. (1965)
Fecal-oral
Transmission by a resistant fecal form of T. gondii demonstrated	Hutchison (1965)
Coccidian phase recognized	Hutchison et al. (1970, 1971); Frenkel et al. (1970); Dubey et al. (1970a, 1970b); Sheffield and Melton (1970); Overdulve (1970)
Definitive and intermediate hosts defined, including excretion of oocysts only by felids	Frenkel et al. (1970); Miller et al. (1972); Jewell et al. (1972)
First oocyst-inhaled/ingested human toxoplasmosis outbreak described	Teutsch et al. (1979)
Genetics and Different Genetic T. gondii Strains
Recombinants and genetic crosses produced	Pfefferkorn and Pfefferkorn (1980)
Isoenzyme differences used to distinguish T. gondii strains	Dardé et al. (1987); Tibayrene et al. (1991)
Restriction fragment length polymorphism used to group T. gondii strains into 3 Types (I–III)	Sibley et al. (1992); Howe and Sibley (1995)
National, continental, intercontinental, and pandemic T. gondii strains distinguished	Lehmann et al. (2006)
T. gondii genome annotated	Khan et al. (2005)
Immunity and Protection
T. gondii neutralizing antibody recognized	Sabin and Ruchman (1942)
Antibodies found to kill extracellular but not intracellular T. gondii	Sabin and Feldman (1948)
Protection transferred by immune lymphoid cells but not by antibodies	Frenkel (1967)
Interferon gamma found to be main cytokine for protection	Suzuki et al. (1988)
Role of CD4+ and CD8+ cells in protection defined	Gazzinelli et al. (1991)
Toxoplasmosis in Humans
Congenital
First proven case of congenital toxoplasmosis described	Wolf et al. (1939)
Typical tetrad clinical signs described (hydrocephalus or microcephalus, chorioretinitis, intracerebral calcification)	Sabin (1942)
Acquired
First case in a child	Sabin (1941)
Fatal toxoplasmosis in adults found	Pinkerton and Weinman (1940)
Lymphadenopathy recognized as the most frequent symptom	Siim (1956); Beverley and Beattie (1958)
Susceptibility to toxoplasmosis in AIDS patient recognized	Luft et al. (1983)
Chronic infection
Cysts found in autopsy slides, indicating chronic asymptomatic infection	Plout (1946); Kean and Grocott (1947)
Toxoplasmosis in Other Animals
Toxoplasmosis found in a domestic animal, dog	Mello (1910)
Immunosuppressive Canine Distemper Virus influenced clinical toxoplasmosis outcome in dogs	Campbell et al. (1955)
Epidemic toxoplasmosis abortions in sheep recognized	Hartley and Marshall (1957)
Toxoplasmosis in animals reviewed critically	Dubey and Beattie (1988)
Toxoplasmosis found a common infection in a marine mammal species, sea otter	Cole et al. (2000)
Diagnosis
Novel Sabin–Feldman dye test described	Sabin and Feldman (1948)
Toxoplasma skin test as a survey tool	Frenkel (1948)
Tests developed to detect IgM antibodies in cord blood	Remington et al. (1968); Desmonts et al. (1981)
Simple direct agglutination test developed (DAT, MAT)	Desmonts and Remington (1980); Dubey and Desmonts (1987)
First validation of a serologic test using isolation of the parasite as standard	Dubey et al. (1995a); Dubey (1997)
PCR test developed to detect T. gondii DNA using B1 gene	Burg et al. (1989)
Treatment
Sulfonamides found effective against T. gondii	Sabin and Warren (1942)
Pyrimethamine found synergistic with sulfonamides against dividing tachyzoites	Eyles and Coleman (1953)
Folic acid and yeast improve activity of sulfadiazine and pyrimethamine	Fre...