The American, British and Dutch responses to unlinked anonymous HIV seroprevalence studies: an international comparison

Occult HIV infection in a large sample of health-care users in Lombardy, Italy in 2014-2015: implications for control strategies

We estimated the number of people unaware of their human immunodeficiency virus (HIV) infection in our province, Pavia (population 540 000) in Lombardy, Italy, by means of anonymous unlinked testing of 10 044 serum/plasma samples residual from clinical analyses at the outpatient clinic of Policlinico San Matteo in 2014 and 2015. Ethical and legal approval was obtained prior to study start. Samples were irreversibly anonymised, only retaining gender and 5-year age class. Five sample pools were tested for HIV using LIAISON® XL MUREX HIV Ab/Ag (DiaSorin, Saluggia, Italy). If the pool tested positive, individual samples underwent confirmatory tests, Innotest HIV Antigen mAb (Fujirebio Europe, Gent, Belgium) and HIV BLOT 2·2 (MP Diagnostics, Singapore). Among the 10 044 samples processed, eight were confirmed positive (0·08%, 95% confidence interval 0·03-0·16%), all were males and age was >50 in 3 (37·5%). If projected to the entire population of the Pavia province, this would result in approximately 1000 people unaware of their HIV infection, with age older than expected. In Italy, HIV testing is voluntary, universally free-of-charge and (upon request) anonymous. Nevertheless, this study demonstrates that it is suboptimally employed, and that new strategies and population-level actions will be needed to achieve better implementation of HIV testing and HIV control in our province.

Testing for HIV without specific consent: a short review

The practice of testing for human immunodeficiency virus (HIV) without the specific knowledge and consent of the patient raises ethical and legal issues. This report argues that diagnostic HIV testing of specific patients, without their consent, is unethical and may also be illegal. Testing for HIV prevalence on an anonymous, unlinked basis, however, is an important aspect of public health surveillance, and the ethics of clinical intervention should not be confused with the ethics of epidemiological research. Specific consent is usually desirable in view of privacy concerns, the importance of patient autonomy, and the potential for conflict of interest. However, where otherwise appropriate, the law should be clarified to permit nonconsensual HIV testing to proceed legally, possibly following scrutiny by an institutional ethics committee.