Today, many people are unable to get tested for diseases because they cannot access diagnostic services. Many are incorrectly diagnosed. As a result, they do not receive the treatment they need and, in some cases, may actually receive the wrong treatment.
For example, an estimated 46% of adults with Type 2 diabetes worldwide are undiagnosed, risking serious health complications and higher health costs. Late diagnosis of infectious diseases such as HIV and tuberculosis increases the risk of spread and makes them more difficult to treat.
To address this gap, WHO recently released its first Essential Diagnostics List, a catalogue of the tests needed to diagnose the most common conditions as well as a number of global priority diseases.
“An accurate diagnosis is the first step to getting effective treatment,” says Dr Tedros Adhanom Ghebreyesus, WHO Director-General. “No one should suffer or die because of a lack of diagnostic services, or because the right tests were not available.”
The list concentrates on in vitro tests – i.e. tests of human specimens like blood and urine. It contains 113 products: 58 tests are listed for detection and diagnosis of a wide range of common conditions, providing an essential package that can form the basis for screening and management of patients. The remaining 55 tests are designed for the detection, diagnosis and monitoring of “priority” diseases such as HIV, tuberculosis, malaria, hepatitis B and C, human papillomavirus and syphilis.
Some of the tests are particularly suitable for primary health care facilities, where laboratory services are often poorly resourced and sometimes non-existent; for example, tests that can rapidly diagnose a child for acute malaria or glucometers to test diabetes. These tests do not require electricity or trained personnel. Other tests are more sophisticated and therefore intended for larger medical facilities.
“Our aim is to provide a tool that can be useful to all countries, to test and treat better, but also to use health funds more efficiently by concentrating on the truly essential tests,” says Mariângela Simão, WHO Assistant Director-General for Access to Medicines, Vaccines and Pharmaceuticals. “Our other goal is to signal to countries and developers that the tests in the list must be of good quality, safe and affordable.”
For each category of test, the Essential Diagnostics List specifies the type of test and intended use, format, and if appropriate for primary health care or for health facilities with laboratories. The list also provides links to WHO Guidelines or publications and, when available, to prequalified products.
Similar to the WHO Essential Medicines List, which has been in use for four decades, the Essential Diagnostics List is intended to serve as a reference for countries to update or develop their own list of essential diagnostics. In order to truly benefit patients, national governments will need to ensure appropriate and quality-assured supplies, training of health care workers and safe use. To that end, WHO will provide support to countries as they adapt the list to the local context.
The Essential Diagnostics List was developed following an extensive consultation within WHO and externally. The draft list was then considered for review by WHO’s Strategic Advisory Group of Experts on In-Vitro Diagnostics – a group of 19 experts with global representation.
WHO will update the Essential Diagnostics List on a regular basis. In the coming months, WHO will issue a call for applications to add categories to the next edition? The list will expand significantly over the next few years, as it incorporates other important areas including antimicrobial resistance, emerging pathogens, neglected tropical diseases and additional noncommunicable diseases.