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Updated: Jul 16, 2026

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
[Delayed diagnosis of HIV infection in the Spanish VACH cohort [1997-2002]]
Ramón Teira Cobo1, Ignacio Suárez Lozano, Juan Miguel Santamaría Jáuregui
1Servicio de Enfermedades Infecciosas, Hospital de Basurto, Bilbao, España. retira@hbas.osakidetza.net
Objective:
To study the prevalence of delayed diagnosis of HIV infection and associated factors.
Methods:
A cross sectional study of patients included in the Spanish VACH cohort who had been diagnosed with HIV infection between 1997 and 2002 was performed. Delayed diagnosis was defined as patients diagnosed with HIV infection and AIDS simultaneously or within the first month after the first positive serologic test, or those with a first CD4+ cell count below 200/ml. The epidemiological characteristics of these patients were compared with those of the remaining patients
Results:
Of 2,820 new cases of HIV infection, delayed diagnosis was found in 506 (18%). These patients differed from the remaining patients in their lower mean age and higher HIV viral load, as well as in their distribution by sex (higher proportion of males), occupational status, history of incarceration in prison, and HIV-risk transmission group. The median survival during follow-up was significantly lower among AIDS patients with a delayed diagnosis.
Conclusions:
Delayed diagnosis remains a cause for concern in our environment, due to its magnitude and its association with mortality. Some epidemiological characteristics provide clues to guide future programs directed at increasing information and improving prevention.
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