Point-of-Care Testing for Sexually Transmitted Infections

Recent Advances and Implications for Disease Control

Joseph D. Tucker; Cedric H. Biena; Rosanna W. Peeling

Disclosures

Curr Opin Infect Dis. 2013;26(1):73-79. 

In This Article

Abstract and Introduction

Abstract

Purpose of review Sexually transmitted infections (STIs) remain a major global public health issue, with more than 448 million incident bacterial infections each year. We review recent advances in STI point-of-care (POC) testing and implications for STI prevention and control.

Recent findings Accurate immunochromatographic assays to detect HIV, hepatitis C virus (HCV) and syphilis antibodies have made home or supervised self-testing possible. Several studies have demonstrated feasibility and excellent test characteristics for HIV, HCV and syphilis POC tests. Rapid oral HIV tests are now available for purchase at retail sites across the United States. Combined HIV and syphilis tests using a single finger prick blood sample are under evaluation.

Summary Oral POC STI tests with comparable performance to blood-based POC tests are available for self-testing. POC tests can expand screening, improve syndromic management and reduce loss to follow up. POC STI tests have the potential to facilitate prompt treatment and partner services. POC STI tests create opportunities for new social and financial models of community-based testing services. Increasing equity and access to testing will create challenges in linkage to care, quality assurance, partner services and surveillance. These important developments warrant research to understand appropriate contexts for implementation.

Introduction

The WHO estimates that worldwide, 448 million new cases of curable sexually transmitted infections (STIs; specifically syphilis, gonorrhoea, chlamydia and trichomoniasis) are diagnosed each year.[1] Chlamydial and gonococcal infections can lead to chronic pelvic pain, ectopic pregnancy and infertility. Approximately 25% of untreated early syphilis infections during pregnancy result in stillbirth and 14% cause neonatal death.[1] These sequelae are entirely preventable if STI testing is utilized.

STI tests with high sensitivity and specificity are commercially available, but they are often neither affordable nor accessible to many patients in the developing world where STI burden is greatest. Laboratory-based testing often requires patients to return for their test results, leading to loss to follow-up and delays in treatment and partner services. In recent years, advances in detection technology have made a range of point-of-care (POC) tests available.[2,3,4,5,6] It is now possible to screen and diagnose STIs at primary healthcare settings using blood from a finger prick or a noninvasive specimen such as oral exudate ( Table 1 ). Molecular assays that can be performed with minimal user input, but provide fast and highly accurate results, are now available for the detection of chlamydia and gonorrhoea. Innovations in the delivery of these POC tests will ensure widespread access to diagnostics so that patients can benefit from evidence-based treatment at the same clinic visit.[7] POC reader technology can securely transmit remote testing results directly to proximate clinical services, decreasing loss to follow-up and improving linkage and retention to care (Fig. 1).[8]

Figure 1.

Overview of the cascade of sexually transmitted infection services and point-of-care testing functions. POC, point-of-care.

The purpose of this review is to describe technological advancements in the diagnosis of STI at the POC in the past 18 months and the implications for linkage to care, partner services, surveillance and disease control. Although there is no universally accepted definition of POC testing, for the purpose of this review, we define POC test as any test that is simple and can provide a rapid result to guide clinical decisions and follow-up during the same encounter.[9] We searched Pubmed, Scopus and Web of Science using the terms 'rapid testing', 'point-of-care testing', 'self test' and 'home test' and the names of individual STIs. Our review included STIs for which POCs have been developed. We included hepatitis C virus (HCV) because of the importance of homosexual HCV transmission. We included novel multiplex tests that are currently under evaluation.

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