Gram Negative Coccobacilli
Pertussis toxin is produced by;
|D||All of the above|
The above 3 species can cause whooping cough in humans. B.parapertussis and B.bronchiseptica cause milder disease.
The gene for the pertussis toxin is present in all 3 species but expressed only in B.pertussis.
a. Brucella are gram negative cocco-bacilli, non-motile and non-sporing.
b. They are strict aerobes and many strains of B.abortus are capnophilic.
c. Brucellosis is also called Mediterranean/Malta/undulant/Cyprus fever/Bang’s disease.
d. It is a zoonotic disease caused by B. melitensis, B.abortus and B.suis, reservoir hosts of which are sheep/goats, cattle and pigs, respectively.
e. The species identification is very complex and is based on the relative proportions of 2 antigens, A and M, along with CO2 requirement, H2S production, urease enzyme, phage lysis (Tblisi phage) and sensitivity to dyes.
f. Brucella melitensis is the most prevalent worldwide, and it is felt to cause the most severe cases of brucellosis.