Neglected Tropical Diseases (NTDs), long overlooked and intrinsically linked to poverty, affect nearly 2 billion people globally, while the number of people requiring NTD interventions (both preventive and curative) is 1.6 billion.²  This figure parallels the combined burden of HIV/AIDs, tuberculosis, and malaria. NTDs encompass both communicable and non-communicable diseases predominantly prevalent in tropical regions. In tropical regions, these infections account for 20-30% of intensive care unit (ICU) admissions and include a spectrum of conditions.

Notably, NTDs are not exclusive to tropical areas; significant occurrences of these diseases are also reported in the temperate zones. Factors contributing to the rise of these diseases include return of military personnel, increased global travel, population mobility, advancements in commercial aviation, and the existence of key medical facilities. Consequently, the prevalence of NTDs is rising in nations like the United States, United Kingdom, Europe, primarily due to international travel and migration.

Nigeria has the largest burden of NTDs in Sub-Saharan Africa, accounting for 25% of the continent’s total NTDs burden. The Federal Ministry of Health (FMoH) prioritized NTDs and included them among the forty (40) communicable and non-communicable diseases and conditions for integrated disease surveillance and response (IDSR). Currently, the FMoH are addressing the following NTDs based on outcomes of mapping surveys, case searches or high-suspicion index: Preventive-Chemotherapy NTDs (Lymphatic Filariasis, Onchocerciasis, Schistosomiasis, Soil Transmitted Helminths, and Trachoma) and Case-Management NTDs (Leprosy, Buruli Ulcer, Human African Trypanosomiasis, Guinea Worm Diseases, Lymphoedema, Trichiasis, Rabies, Leishmaniasis, Yaws, Dengue, and Mycetoma). The PC-NTDs pose huge disease burden on the population. Nigeria has the highest burden of cases of Onchocerciasis and Schistosomiasis worldwide, greatest number of cases of Lymphatic Filariasis in Africa with Schistosomiasis being endemic in the country. About 50 million persons are at risk of Onchocerciasis while 114 million Nigerians are at risk of Lymphatic Filariasis. 43 million and 35 million persons need treatments for Schistosomiasis and for Soil Transmitted Helminths respectively. Nearly 20 million persons are at risk for Trachoma, while 1.3 million people are infected with Trichiasis.

The epidemiology of NTDs is complex and often related to environmental conditions. Many of them are vector-borne, have animal reservoirs, and are associated with complex life cycle. Consequences arising from climate change, conflict, emerging zoonotic and environmental health threats, as well as continued socio-economic inequalities that have a direct impact on access to healthcare services, adequate housing, safe water, and sanitation, all play a role to the occurrence of NTDs.

The low-income countries have continued to witness persistence of NTDs despite all the efforts in the fight against NTDs. This has remained so due to ignorance, lack of the skill to identify and treat NTDs thus allowing these infectious diseases to continue to flourish in rural communities most especially, mostly affecting women and children. They thrive in areas like conflict zones and hard-to-reach regions, where access to clean water and sanitation is scarce, worsened by climate change. Furthermore, NTDs tend to affect regions without quality healthcare, leaving poor population vulnerable to these often debilitating diseases and newly emerging threats.

It is also said that the proliferation of these diseases is exacerbated by poverty, substandard housing conditions, malnutrition, HIV/AIDS, and inadequate health system. All these factors make their public-health control challenging. In addition to this, it’s under-reporting and the quantification of disease burden, has proved difficult. Furtherance to this, there is lack of consistent funding in the path of tackling NTDs.

Neglected Tropical Diseases ranks among the most devastating groups of communicable diseases. They are recognized as a public health problem especially among poor populations, thus connoting health inequality. Over 40% of the global NTD burden is concentrated in Africa. Annually, tropical infectious and parasitic diseases claim approximately 15 million lives, predominantly in developing countries.

Neglected tropical diseases (NTDs) are challenging to individuals, families and the country at large. NTDs can result in severe pain, disabilities and deformities, malnutrition, stunted growth, cognitive impairment, disfigurement, stigmatization, and anemia, indirectly impacting on maternal mortality. They cause severe pain and long term disability and lead to death for more than 170,000 people per year.

The effects from NTDs such as deformed legs and blindness results in social isolation. Amongst children, infection leads to malnutrition, cognitive impairment, stunted growth, and the inability to attend school. Social isolation and physical ailments make working difficult for people with NTDs. Many people are unable to provide for themselves or their families, impacting long-term earnings.¹¹ They also deprive people of access to employment opportunities.¹¹

The diagnosis of many NTDs is often hindered by unstable diagnostic methods, and the overlapping clinical features of tropical diseases pose significant challenges for initial diagnosis. A systematic diagnostic approach includes:

i. detailed travel history to specific continents or countries;

ii. exposure to unique environmental conditions such as forests, farms, water bodies, or consumption of exotic foods;

iii. assessment of the incubation period;

iv. identification of subtle variances in pattern of organ involvement and clinical manifestations. However, the complex nature of the epidemiology of NTDs, and the great influence of environmental conditions surrounding the occurrence of NTDs combines to make their public-health effects more devastating and challenging to manage and control. The global roadmap developed by WHO calls for stronger accountability, intensified cross-cutting approaches, and a change in the operating model and culture with every country affected taking full responsibility and ownership of their actions, towards eradicating NTDs by 2030.

The World Health Organization recommends five (5) core strategic interventions to accelerate the prevention, control, elimination, and eradication of NTDs. Past experiences has demonstrated that while one intervention may predominate for the control of one specific disease or disease groups, a more effective impact on both morbidity and transmission results when interventions are combined and delivered simultaneously. These interventions include:

Innovative and intensified disease management

This involves individual disease management. The concept was first devised almost 2 decades ago to tackle diseases that require individual-level care either because they are complex to manage or because effective diagnostic tools and medicines are unavailable.

Preventive chemotherapy

This is the large scale delivery of safe, single-administration, quality-assured medicines, either alone or in combination at regular intervals, to entire population groups.

Vector control

This serves as an important cross-cutting activity to enhance the impact of other strategic interventions, with specific focus on prevention of selected NTDs whose transmission cycle relies on vector or intermediate hosts.

Veterinary public health

This is the component of public health that focuses on the application of veterinary science as a contribution to the protection and improvement of human well-being.

Provision of safe water, sanitation, and hygiene

Providing safe water, sanitation, and hygiene (WASH) is a key component of the revised global strategy and is critical for preventing and providing care for most NTDs

Furthermore, One Health which is an integrated unifying approach that aims to sustainably balance and optimize the health of people, animals, and ecosystem seems to plays a role in the prevention of NTDs. It recognizes that the health of humans, domestic and wild animals, plants, and the environment (including ecosystem) are closely linked and interdependent. The Food and Agriculture Organization of the United Nations (FAO), the World Organization for Animal Health (OIE), the UN Environment Programme and the World Health Organization (WHO), known as the Quadripartite, are working together to promote cross-sectorial collaboration to address risks from zoonosis and other public health threats that exists or emerge at the human-animal-ecosystem interface.

In the Nigerian context, the progress in the management of NTDs has been dragging due to the lack in adequate understanding of the disease.  However, Nigeria has interrupted Onchocerciasis and eliminated Trachoma and Lymphatic Filariasis in Nasarawa and Plateau States. The other states that interrupted Onchocerciasis are Abia, Delta, Enugu, and Imo while Ebonyi also eliminated Trachoma.  Noma was included as the 21^st NTDs and this was largely due to the Nigeria efforts in raising global awareness about the disease.

Neglected Tropical Diseases pose a significant public Health threat, disproportionately affecting over 1 billion people worldwide, particularly in poverty-stricken areas, and require urgent attention through increased awareness, improved healthcare access, and collaborative efforts to prevent, control, and eliminate these debilitating diseases.