With regards to Gram-negative pathogens in ocular infections in Lagos, we found P. aeruginosa as the predominating strain with an isolation rate of 9.7%, whereas in a previous study in the same environment, Klebsiella pneumoniae was the most commonly isolated pathogen (12.9%) followed by P. aeruginosa (8.2%).
CA16 was the dominant circulating virus during the outbreaks in year 2002, 2005, and 2007; whereas EV71 was the predominating strain for the epidemics in 2006 and 2008 [10], [26].
From January through June 2009, A/Brisbane/59/2007-like clade 2B virus continued to be the predominating strain.
When larvae are co-infected with two isogenic, but differently labeled, S. aureus clones, the infection evolves by forming focal lesions that are predominantly monoclonal and, during the course of overwhelming infection, the ratio between the original strains is often skewed towards one predominating strain (Prajsnar et al., 2012).
Also, in several other studies a few predominating strains associated with most intramammary infections in a region have been identified [ 9, 10, 12, 17].
Key among them is an important theme in the theory of evolution of epidemics competition among strains of a rapidly evolving virus can produce an equilibrium in which the predominant strain is less virulent and slower to travel than the strain that predominated at the onset of the epidemic [ 43– 43].
In some years, 2 strains predominated, so we defined predominant strains as those identified in at least 33% of specimens in the year.
Saa variant 1 predominated (18 strains) and was distributed in strains isolated both from cattle and from meat.
In Australia, we have shown by single nucleotide polymorphism (SNP) typing that among B. pertussis isolates, ptxP3 containing strains predominate (7 ), and these strains belong to SNP cluster I (8, 9 ).
In contrast, European type sequences predominated in strains from Amerindian Lima shantytown residents, but with some 12% Amerindian or East Asian-like admixture, which indicates displacement of ancestral purely Amerindian strains by those of hybrid or European ancestry.
