Is there a difference between serotype and strain?
Serotypes may be viewed as a further categorization of strains. This is because of the fact that strains of different microorganisms can also have varying antigens and thus a need to categorize this further based on these molecules.
What do you mean by serotypes?
Serotypes are groups within a single species of microorganisms, such as bacteria or viruses, which share distinctive surface structures.
What is difference between different serotypes of a virus?
A serotype or serovar is a distinct variation within a species of bacteria or virus or among immune cells of different individuals. These microorganisms, viruses, or cells are classified together based on their surface antigens, allowing the epidemiologic classification of organisms to the subspecies level.
Are Serovars strains?
thousands of different strains (called serovars, for serological variants), which differ from one another mainly or solely in the antigenic identity of their lipopolysaccharide, flagella, or capsule. Different serovars of enteric bacteria—such as E.
How are serotypes determined?
The specific serotype of a microorganism can be determined by mixing samples of the microorganism with different samples of antibodies. If a mixture of the microorganism and antiserum cause clumps to form, the serotype can be identified.
How do you identify a serotype?
The serotype is determined by agglutination of the bacteria with specific antisera to identify variants of somatic (O) and flagella (H) antigens. This provides the antigenic formula of the strain associated to the name and subspecies of the serotype.
How do you write a serotype?
Serotype names designated by antigenic formulae include the following: (i) subspecies designation (subspecies I through VI), (ii) O (somatic) antigens followed by a colon, (iii) H (flagellar) antigens (phase 1) followed by a colon, and (iv) H antigens (phase 2, if present) (for example, Salmonella serotype IV 45:g,z51: …
What is serotypes in dengue?
Dengue is caused by a virus of the Flaviviridae family and there are four distinct, but closely related, serotypes of the virus that cause dengue (DENV-1, DENV-2, DENV-3 and DENV-4). Recovery from infection is believed to provide lifelong immunity against that serotype.
What is the difference between dengue serotypes?
Previous reports of dengue in children have suggested that infection with secondary DENV-2 is more likely to result in severe disease compared with other serotypes. In contrast, primary DENV-1 cases were more overt whereas primary DENV-2 and DENV-3 cases were usually silent.
How are dengue serotypes different?
Dengue infections are caused by four closely related viruses named DEN-1, DEN-2, DEN-3, and DEN-4. These four viruses are called serotypes because each has different interactions with the antibodies in human blood serum.
What is serotype 2 dengue?
Dengue serotype 2 (DEN-2) viruses with the potential to cause dengue hemorrhagic fever have been shown to belong to the Southeast (SE) Asian genotype. These viruses appear to be rapidly displacing the American genotype of DEN-2 in the Western Hemisphere.
How many serovars of Salmonella are there?
There are currently 2,463 serotypes (serovars) of Salmonella (18).
How do you write Salmonella Serovars?
These can also be abbreviated as Salmonella serovars Paratyphi A, Paratyphi B, and Paratyphi C. Typhoidal Salmonella refers to serovars that cause typhoid or paratyphoid fever. Nontyphoidal Salmonella (NTS) refers to all other serovars.
How would you differentiate between serotypes of E. coli?
E. coli have traditionally been serotyped using antisera against the ca. 186 O-antigens and 53 H-flagellar antigens. Phenotypic methods, including bacteriophage typing and O- and H- serotyping for differentiating and characterizing E.
How many serotypes does E. coli have?
More than 700 serotypes of E. coli have been identified. Most varieties of E. coli are harmless or cause relatively brief diarrhea, but a few strains can cause severe abdominal cramps, bloody diarrhea and vomiting.
What is serovar and genotype?
Serovar is simply a synonym for serotype. Don’t get either term confused with genotype. Genotype refers to an organism’s genetic makeup or constitution. This is not the same thing as phenotype! The latter refers to the expressed features of an organism. A genotype is the entire collection of an organism’s genetic information.
What is a serotype?
Serotypes were discovered by the American microbiologist Rebecca Lancefield in 1933. The immune system is capable of discerning a cell as being ‘self’ or ‘non-self’ according to that cell’s serotype. In humans, that serotype is largely determined by human leukocyte antigen (HLA), the human version of the major histocompatibility complex.
How does the genotype influence the type of strain and serotype?
Therefore, the genotype may influence both the type of strain and serotype of an organism given that it is the genetic makeup of an organism that is one of the factors that influence specific traits. The genus Salmonella includes Gram-negative, facultative anaerobes that are suggested to have evolved from E. coli bacteria.
How do you identify serovars?
Serovars may be established based on virulence factors, lipopolysaccharides in Gram-negative bacteria, presence of an exotoxin (pertussis toxin in Bordetella pertussis, for example), plasmids, phages, or other characteristic which differentiate two members of the same species.