**4. Results**

212 Epidemiology Insights

To collect oral fluids, Oracol oral fluid collection kits (Malvern Medical Developments, Worcester, UK) were used. The main advantages for replacing serum with oral fluid were easy access and non-invasive collection. After collection, oral fluid samples were kept refrigerated and sent to the national reference laboratory for HIV/AIDS in the respective

The oral fluid samples were sent for the analysis by each national reference laboratory to the Teaching Hospital-University of Verona, Immunology Unit, Verona, Italy. EIA testing GENSCREEN HIV 1/2 version 2, BIO-RAD on oral fluid sample was performed according to the manufacturer's instructions. All positive samples were confirmed with a Western Blot test. In terms of quality control, for each oral fluid sample, a total IgG antibodies ELISA test was performed in order to assess the sample suitability for testing. Samples below 3.5 titre (cut-off) were excluded from the study as invalid (see Fig. 1: Survey testing algorithm). A validation

(1) Rapid Immunocromatograpy Determine HIV 1/2 ( Unipath Ltd, Bedford UK) CE marked for serum

(2) HIV 1/2 BLOT 2.2 ( MP Biomedical, China) CE marked for serum

Fig. 1. HIV testing algorithm on oral fluid samples

**3.3 Laboratory testing** 

**3.3.2 HIV testing** 

were used

**3.3.1 Oral fluid sampling and testing** 

countries no more than 72 hours after collection.
