Article

Viral phenotype and fitness.

Department of Public Health, University Tor Vergata Rome, Italy.
The new microbiologica: official journal of the Italian Society for Medical, Odontoiatric, and Clinical Microbiology (SIMMOC) (impact factor: 1). 05/2004; 27(2 Suppl 1):71-6. pp.71-6
Source: PubMed

ABSTRACT The fitness is a parameter defining the replicative adaptation of an organism to its environment. Recently, the HIV research field has shown renewed interest in the replicative capacity of human immunodeficiency virus type 1 (HIV-1) due to the potential impact of ex vivo viral fitness on population size, drug resistance, and disease progression. In the absence of antiretroviral therapy, strains containing drug-resistance mutations have a reduced fitness compared to the wild-type (wt) quasispecies within the population. Therefore, selective pressure of drug therapy leads to dramatic shifts in the quasispecies distribution and fitness of those mutants with decreased sensitivity to the respective antiretrovirals. Even if the presence of drug resistance mutations can decrease the viral fitness and explain a sustained CD4+T cell count in presence of high viral load, the current treatment guidelines advocate a switch in antiretroviral treatment regimens following the emergence of primary drug resistant mutations and possibly prior to selection of compensatory changes.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

antiretroviral therapy
 
antiretroviral treatment regimens
 
compensatory changes
 
current treatment guidelines advocate
 
disease progression
 
dramatic shifts
 
drug resistance mutations
 
drug-resistance mutations
 
ex vivo viral fitness
 
HIV research field
 
human immunodeficiency virus type 1
 
parameter defining
 
population size
 
primary drug resistant mutations
 
reduced fitness
 
replicative adaptation
 
replicative capacity
 
respective antiretrovirals
 
sustained CD4+T cell count
 
viral fitness
 

M Andreoni