NCEZID partners with CDC Foundation and Pfizer on cryptococcal screening in South Africa

An image of a man and boy in south africa looking into the camera

The National Center for Emerging and Zoonotic Infectious Diseases (NCEZID) and the CDC Foundation are using a grant from Pfizer to tackle cryptococcal meningitis (CM), a leading cause of death among people with HIV/AIDS. Through this partnership, screening strategies and costs are evaluated to provide policymakers and program implementers with the information they need to turn policy into action. Screening and pre-emptive treatment for early cryptococcal disease offer the opportunity to reduce burdens on health systems and to save lives. This partnership began in 2015 in South Africa and has helped the country finalize its strategy and implementation of national screening for early cryptococcal disease in October 2016.

CM is a serious, fungal opportunistic infection that can attack patients with advanced HIV/AIDS. The condition requires hospitalization and treatment with amphotericin B, an intravenous antifungal medication. Annually, there are approximately 300,000 new cases worldwide. Sub-Saharan Africa has the highest number of estimated cases per year, followed by East, South, and Southeast Asia. In low-resource settings, with a lack of access to healthcare services, many patients with CM receive sub-optimal treatment. Patients often are not diagnosed early enough and do not receive care until the disease has advanced too far for treatment to be effective. Amphotericin B is very expensive or not available. Undetected, CM has been linked to increased deaths when patients with advanced HIV begin anti-retroviral treatment. One-third to one-half of all patients with CM will die from it.

A rapid dipstick test to diagnose cryptococcal disease, known as the Cryptococcal Antigen Lateral Flow Assay (CrAg LFA), was recently developed by fungal diagnostics manufacturer IMMY, based in Norman, Oklahoma. CrAg LFA is capable of detecting antigen in the blood weeks to months in advance of the onset of CM. This simple test requires minimal laboratory infrastructure and provides results in 10 minutes at a cost of $3-4 per person, offering significant advantages over traditional methods in resource-limited areas. CrAg LFA is highly accurate and can provide results quickly to inform treatment decisions, versus traditional tests that may miss positive cases and take weeks to return.

Early detection before meningitis develops means that patients can be treated with inexpensive pills that are readily available in low resource areas outside of a hospital, making this newer test an ideal screening tool. The World Health Organization has recommended CrAg LFA screening for patients with advanced HIV, and more than 20 countries have since included screening in national policy, though few have begun to implement screening programs. The successful evaluation in South Africa indicates that a similar approach could be expanded in other countries. Partnering together, CDC and the CDC Foundation will continue to provide ministries of health and HIV programs with the critical information needed to implement such programs, and to save lives through prevention and access to needed treatments.