For decades, access to essential medicines has been a major priority in global health. The WHO Essential Medicines List (EML) was published over 40 years ago, to address the need for countries to make essential medicines more accessible and affordable to patients, especially in low income countries. Over time, it has become clear that medicines are necessary, but not sufficient to offer quality primary care, prevent outbreaks, and address threats such as antimicrobial resistance and the global epidemic of non-communicable (NCD) diseases. Diagnosis is the first critical step to offer quality healthcare and to contain emergencies.
In a ground-breaking move, WHO published the first edition of the WHO Model list of Essential In Vitro Diagnostics (or EDL) on 15 May 2018. By doing so, WHO highlighted the fact that diagnostics are essential components for universal health coverage (UHC), to address health emergencies, and promote healthier populations, which are the three strategic priorities of WHO. The EDL complements the WHO EML and will enhance its impact. After all, medicines work best when they are targeted to the right condition, for the right patient, at the right time.
The WHO EDL defines essential diagnostics as those “that satisfy the priority health care needs of the population and are selected with due regard to disease prevalence and public health relevance, evidence of efficacy and accuracy, and comparative cost-effectiveness.”
For its first edition, the EDL contains tests that are considered general laboratory tests, and tests that are considered disease-specific, aimed at conditions of public health importance (HIV, tuberculosis, malaria, hepatitis B and C, syphilis and human papilloma virus). The disease-specific tests were selected based on WHO guidelines. The general laboratory tests were selected from other WHO guidance documents on clinical laboratories and pathology, the WHO list of priority medical devices, and disease-specific clinical guidelines. The EDL is in fact a list of categories of tests instead of individual test brands. The EDL groups tests by two major levels of the healthcare delivery system: primary care facilities versus facilities with clinical laboratories.
WHO has already begun the process of expanding the list to other areas through a yearly call for submissions of additional categories of tests. Through these calls it will also be possible to submit corrections, clarifications or even deletions. The current call is open to all disease areas but WHO is particularly interested in submission related to IVDs for antimicrobial resistance, neglected tropical diseases, NCDs, outbreaks/emergencies and sepsis. After a pre-submission, screening process, full submissions will be invited, and will require additional information on the tests, performance, quality and impact (with a focus on evidence-based information). These full submissions will be reviewed by WHO and selected experts. The WHO has appointed a Strategic Group of Experts on In Vitro Diagnostics (SAGE IVD) to advise on the development of the EDL. The submissions and the reviews will be posted on the WHO website. The second edition of the EDL is expected to be published in Spring 2019.
Additions or changes to the EDL will be done on an annual basis (compared to the 2-year review cycle of the EML). This difference reflects that fact that there is a lot of “catching up” to do to develop a comprehensive EDL but also the fact that the IVD field is very dynamic with a development cycle which is more rapid than for vaccines and medicines. The EDL process will need to be nimble while rigorous to rapidly adapt to technological or policy changes.
Although the WHO EDL is a critical step in the right direction, the impact of the EDL will be enhanced when countries adapt the EDL to their own national needs and put in place mechanisms to implement the EDL. One critical area to address is the poor state of laboratories in many low and middle-income countries. In the absence of a strong laboratory network, healthcare providers often rely on empirical therapy, with adverse patient outcomes.
Some countries are already working very actively to develop their own EDL, and we hope other countries will follow suit. To help countries develop their own national EDL and strengthen laboratory capacity, WHO is developing a web portal to centralize and thus facilitate access to all WHO documents that support the selection and use of IVDs. This portal is expected to be available later this year and will include IVD and laboratories relevant documents and links on policies & strategic plans, laboratory set up, IVD for primary care setting, human resources, laboratory quality management, regulation and market, procurement and supplies, innovation, as well as global collaborations.
In order to improve access to essential IVDs, the EDL is really the first of many steps that need to be done. For procurement, it will be necessary to develop technical specifications for the tests in the list. Regulatory approval of IVDs also needs to be strengthened and harmonized globally to ensure quality and access. Supply and affordability of IVDs on the EDL will also need to improve.
For too long, diagnostics have been undervalued in global health. With the publication of the WHO EDL, the tide has finally turned. There is now growing recognition that diagnostics are as important as medicines and vaccines. We call on countries to adapt the WHO EDL and make essential tests accessible within the framework of UHC.
Conflicts of interest
All authors were involved in the development of the first WHO Model list of essential in vitro diagnostics. They have no industry or financial conflicts to disclose.