Landscape analysis of NTD diagnostics and considerations on the development of a strategy for regulatory pathways

The One Health Concept

The concept of One Health has been developed as the appreciation that human health is intricately connected to those of other animals and the environment that they inhabit. In recent years, the COVID-19 pandemic and noticeable effects of climate change have encouraged national and international cooperation to apply One Health strategies to address key issues of health and welfare. The United Nations (UN) Sustainable Development Goals have established targets for health and wellbeing, clean water and sanitation, climate action, as well as sustainability in marine and terrestrial ecosystems. The One Health Quadripartite comprises the World Health Organization (WHO), the World Organization for Animal Health (WOAH-formerly OIE), the United Nations Food and Agriculture Organization (FAO) and the United Nations Environment Programme (UNEP). There are six areas of focus which are Laboratory services, Control of zoonotic diseases, Neglected tropical diseases, Antimicrobial resistance, Food safety and Environmental health. This article discusses the concept of One Health by considering examples of infectious diseases and environmental issues under each of those six headings. Biomedical Scientists, Clinical Scientists and their colleagues working in diagnostic and research laboratories have a key role to play in applying the One Health approach to key areas of healthcare in the 21st Century.

[Reliability evaluation in rural Congo of the calibrated blood smear technique to assess Loa loa microfilaremia level]

Background-Rationale

The diagnosis of Loa loa microfilaremia consists in the observation, using a microscope, of microfilariae in a sample of peripheral blood spread on a slide and subsequently stained (the "blood smear technique"). The accurate quantification of Loa loa microfilaremia is important because the choice of the first intention treatment depends on the patient's microfilaremia: severe adverse events can occur in individuals with high microfilarial densities when treated with ivermectin or diethylcarbamazine, the latter drug being the only one which can definitively cure the infection. However, despite the widespread usage of this technique and its role in guiding clinical management of the patient, estimates of its reliability remain scarce.

Materials and methods

We evaluated the reliability (reproducibility and repeatability) of blood smear technique using several sets of 10 L. loo-positive slides, randomly selected, and considered the results with regard to regulatory requirements. The slides had been prepared as part of a clinical trial conducted in Sibiti, Republic of Congo, a region where loiasis is endemic.

Results

The estimated and acceptable coefficients of repeatability (NB: the lower, the better) were 13.6% and 16.0%, respectively. The estimated and acceptable coefficients of intermediate reliability (reproducibility) were 15.1% and 22.5%, respectively. The poorest coefficient of intermediate reliability was 19.5% when the tested parameter was related to the technician who performed the readings (10.7% when the reading day was changed). The inter-technician coefficient of variation assessed using 1876 L. loo-positive slides was 13.2%. The coefficient of inter-technician variation considered acceptable was estimated at 18.6%. Discussion-Conclusion. All estimated coefficients of variability were lower than the calculated acceptable coefficients suggesting reliability of the technique, although the lack of laboratory references precludes any conclusion on the quality of this diagnosis. It is imperative to implement a quality system and standardization of procedures for the diagnosis of L. loo microfilaremia, both in endemic countries and in the rest of the world, where the demand for diagnosis has been increasing for years.

African institutions will lead on the road to end neglected tropical diseases

Globally, more than one billion people suffer from one or more neglected tropical diseases (NTDs). These diseases create enormous suffering, rob individuals of social and economic opportunities, and set-back countries’ development efforts. It is now clear that transmission and elimination of many NTDs is attainable in our lifetime. The elimination of NTDs will not happen without a concerted effort and plan to ensure that the most affected countries have a robust clinical, public health, laboratory, pharmaceutical, and research capacity to ensure that the last mile towards reaching elimination is not only reached, but sustained. This means increasing strategic investments to develop and strengthen the NTD health workforce, develop and integrate innovative diagnostic approaches, effective treatments, and responsive surveillance systems. Equally important is ensuring that people living with lifelong disabilities resulting from NTDs receive the care and support they need to live healthy, productive, and fulfilling lives. African-based national non-governmental organizations, the private sector, research institutions, and governments play a vital role as they work to attain ambitious NTD elimination and control goals put forward by the global health community. The recent elimination of onchocerciasis in Niger, trachoma in Burundi and Malawi as well as ongoing progress to eliminate lymphatic filiariasis in Kenya and other sub-Saharan Africa countries demonstrate the capacity of African leadership in NTD control and elimination efforts.

COVID-19: A unique opportunity to improve laboratory capacity for neglected tropical diseases in sub-Saharan Africa

While many public health and university laboratories have become involved in COVID-19 testing during the pandemic, these laboratories now run the risk of being underutilized as COVID-19 testing wanes. This is particularly true of established COVID-19 laboratories in many low- and middle-income countries (LMICs). In this article, we make a case for repurposing many of these laboratories to support control programs for neglected tropical diseases (NTDs) in endemic countries as they contemplate how to strengthen laboratory capacity for all endemic and emerging epidemiological diseases.