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Amplifying and Quantifying HIV-1 RNA in HIV Infected Individuals with Viral Loads Below the Limit of Detection by Standard Clinical Assays
Published on: September 26, 2011
HIV type 1 non-B subtype prevalence in Spain, 1997-1998
L García-Albert1, M Ortiz, A García-Saiz
1Centro Nacional de Microbiología, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain. lgarcia@isciii.es
AIDS Research and Human Retroviruses
|October 17, 2001
Summary
The study found that non-B subtypes of Human Immunodeficiency Virus type 1 (HIV-1) are present in Spain, with a prevalence rate of 1.13%. While subtype B is most common, other subtypes were detected in newly diagnosed patients.
Area of Science:
- * Virology and Epidemiology
- * Infectious Diseases
Background:
- * Human Immunodeficiency Virus type 1 (HIV-1) exists in various subtypes, with subtype B historically predominant in Western countries.
- * Understanding the prevalence of non-B subtypes is crucial for effective diagnostics, treatment, and public health strategies.
Purpose of the Study:
- * To determine the prevalence of HIV-1 non-B subtypes among newly diagnosed patients in Spain.
- * To genetically characterize identified non-B subtypes.
Main Methods:
- * Enzyme immunoassay (EIA) using V3 synthetic peptides for initial discrimination between HIV-1 B and non-B subtypes.
- * Genetic analysis of the gp41 region of the env gene for non-B serotyped samples.
- * Collection of samples from 909 newly diagnosed patients across 21 medical units in Spain (October 1997-October 1998).
Main Results:
- * Of 885 serotyped samples, 89.38% were subtype B, 7.91% showed no reactivity, and 2.72% displayed other patterns.
- * Genetic characterization of 65 non-B samples identified subtypes A (5), C (3), and G (2), with 55 remaining as subtype B.
- * The overall prevalence of non-B subtypes in Spain was determined to be 1.13% (95% CI, 0.59-2.21).
Conclusions:
- * While HIV-1 subtype B is predominant in Spain, non-B subtypes are circulating within the population.
- * The findings highlight the importance of ongoing surveillance for diverse HIV-1 subtypes in Spain.
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