'Understanding gender and its intersection with social stratifiers on prevention and care seeking behavior of lymphatic filariasis in Nepal' and other NTD news

This news roundup is a collection of headlines and other items on neglected tropical diseases, and does not reflect the work or the views of the Coalition for Operational Research on Neglected Tropical Diseases or the Neglected Tropical Diseases Support Center.

Lymphatic filariasis

Lymphatic Filariasis Elimination Status: Wuchereria bancrofti Infections in Human Populations after Five Effective Rounds of Mass Drug Administration in Zambia

Belem Blamwell Matap et al., Tropical Medicine and Infectious Disease

Lymphatic filariasis (LF), also commonly known as elephantiasis, is a neglected tropical disease (NTD) caused by filarial parasites. The disease is transmitted via a bite from infected mosquitoes. The bites of these infected mosquitoes deposit filarial parasites, Wuchereria or Brugia, whose predilection site is the lymphatic system. The damage to the lymph system causes swelling in the legs, arms, and genitalia. A mapping survey conducted between 2003 and 2011 determined LF as being endemic in Zambia in 96 out of 116 districts. Elimination of LF is known to be possible by stopping the spread of the infection through large-scale preventive chemotherapy. Therefore, mass drug administration (MDA) with diethylcarbamazine citrate (DEC) (6 mg/kg) and Albendazole (400 mg) for Zambia has been conducted and implemented in all endemic districts with five effective rounds. In order to determine whether LF prevalence has been sufficiently reduced to levels less than 2% antigenemia and less than 1% microfilaremia, a pre-transmission assessment survey (pre-TAS) was conducted. Therefore, post-MDA pre-TAS was conducted between 2021 and 2022 in 80 districts to determine the LF prevalence. We conducted a cross-sectional seroprevalence study involving 600 participants in each evaluation unit (EU) or each district. The study sites (sentinel and spot-check sites) were from districts that were the implementation units (IUs) of the LF MDA. These included 80 districts from the 9 provinces. A total of 47,235 people from sentinel and spot-check locations were tested. Of these, valid tests were 47,052, of which 27,762 (59%) were females and 19,290 (41%) were males. The survey revealed in the 79/80 endemic districts a prevalence of Wb antigens of 0.14% and 0.0% prevalence of microfilariae. All the surveyed districts had an optimum prevalence of less than 2% for antigenaemia, except for Chibombo district. The majority of participants that tested positive for Wuchereria bancrofti (Wb) Antigens (Ag) were those that had 2, 3, and 4 rounds of MDA. Surprisingly, individuals that had 1 round of MDA were not found to have circulating antigens of Wb. The study showed that all the surveyed districts, except for Chibombo, passed pre-TAS. This further implies that there is a need to conduct transmission assessment surveys (TASs) in these districts.

Understanding gender and its intersection with social stratifiers on prevention and care seeking behavior of lymphatic filariasis in Nepal

Abriti Arjyal, Ayuska Parajuli, Chandani Kharel, Mariam Otmani Del Barrio, and Sushil Chandra Baral, Infectious Diseases of Poverty

Lymphatic filariasis (LF) is a debilitating and painful neglected tropical disease and is one of the leading causes of permanent disability. In many countries, the intersection of gender with various social stratifiers has influenced exposure to LF and ultimately impacting the disease burden and its elimination. This study aimed to explore the influence of gender and its intersection with other social stratifiers for the prevention and care seeking behavior of LF in Nepal.


Entomological manual for onchocerciasis elimination programmes

World Health Organization

Medical entomology is essential for the control and elimination of neglected tropical diseases, particularly onchocerciasis. However, there is a shortage of medical entomologists worldwide, especially in countries that are most affected by these diseases, where resources are scarce and promising job opportunities are not offered by the medical entomology sector. Training more health and field workers in entomology therefore remains a critical gap, as highlighted in the road map for neglected tropical diseases 2021–2030. This manual is a new resource for strengthening the capacity of scientists combatting onchocerciasis. It will be a fundamental tool in the last mile as we approach elimination of onchocerciasis, where entomological evaluations and surveillance will be required in all endemic countries in order to achieve verification of elimination.

Prevalence of epilepsy in the onchocerciasis endemic middle belt of Ghana after 27 years of mass drug administration with ivermectin

Kenneth Bentum Otabil et al., Infectious Diseases of Poverty

In onchocerciasis-endemic areas with high ongoing Onchocerca volvulus transmission, a high prevalence of epilepsy has been reported. This study aimed to determine the prevalence and clinical characteristics of epilepsy in the Bono Region of Ghana following 27 years of implementation of ivermectin mass drug administration (MDA).


Mass drug administration launched to combat bilharzia, intestinal worms

Magdaline Saya, The Star (Kenya)

The Ministry of Health has launched a Mass Drug Administration (MDA) exercise aimed at tackling bilharzia and intestinal worms in parts of Nyanza and Western. This comes after an assessment conducted in the two regions and the Coast showed the need to carry out the exercise and interrupt transmission.

Soil-Transmitted Helminthiasis

Persistence of pathogens and bacterial community dynamics in tropical soil after application of raw sewage

Marcus Vinícius Araújo Marques, Bruna Coelho Lopes, Thiago Henrique Ribeiro Silvério, Marcos von Sperling, and Thiago de Alencar Neves, Scientific Reports

The objective of this work was to evaluate the persistence of faecal indicators and pathogenic organisms (Salmonella spp., Escherichia coli and viable helminth eggs) and the structure/diversity of bacterial communities in soil receiving raw sewage (RS) for an extended period of application (3 uninterrupted years). In the experimental design, three treatments were defined: (1) Control soil, characterized by the analysis of a composite sample collected in an area of similar soil, but not a recipient of RS (TSC); (2) Soil receiving conventional mineral fertilization, and furrow irrigation with supply water (TW); and (3) Fertirrigated soil with RS applied by furrows (TF). The results of persistence of pathogenic organisms and indicators in TF indicated a sanitary quality similar to the control soil (TSC), thus potentially bringing low risks of contamination with pathogens present in the soil. The presence of viable helminth eggs was not identified in any treatment studied, because of its low concentration in the raw sewage of the studied system. The TW, TF and TSC treatments had 34.8% of bacterial diversity in common. The bacterial composition of the soil showed a predominance of the Proteobacteria phylum in all treatments studied; however, TF was the one with the highest relative abundance of this phylum (44.8%).


Concerted Efforts Stressed to Prevent, Control Trachoma in Easter Africa Region

Ethiopian News Agency

International Neglected Tropical Diseases (NTDs) Prevention and Control Organization stressed the need for a concerted effort to prevent trachoma disease, which is expanding in the Eastern Africa Region. A continental conference is underway in Arba Minch town of Ethiopia to discuss on the challenges and solutions of lowland and tropical diseases in Africa.


Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs

Compiled and edited by Kathryn Forbes, Maria-Gloria Basáñez, T. Déirdre Hollingsworth, and Roy M. Anderson, The Royal Society Publishing

Twenty neglected tropical diseases (NTDs) are currently prioritised by the World Health Organization for eradication, elimination as a public health problem, elimination of transmission or control by 2030. This issue celebrates progress made since the 2012 London Declaration on NTDs and discusses challenges currently faced to achieve these goals. It comprises 14 contributions spanning NTDs tackled by intensified disease management to those addressed by preventive chemotherapy. Although COVID-19 negatively affected NTD programmes, it also served to spur new multisectoral approaches to strengthen school-based health systems. The issue highlights the needs to improve impact survey design, evaluate new diagnostics, understand the consequences of heterogeneous prevalence and human movement, the potential impact of alternative treatment strategies and the importance of zoonotic transmission.

The Climate-Health Nexus: Time to Build Evidence for Global Health Action

Kemisola Agbaoye, Nigeria Health Watch

Global awareness of the health impacts of climate change is increasing, thanks to communications and discourse at the global level by institutions such as the World Health Organization (WHO) and the Organisation for Economic Cooperation and Development (OECD). Nigeria was declared wild polio-free in 2020, has eliminated the transmission of river blindness and lymphatic filariasis in Nasarawa and Plateau states, and is close to declaring the elimination of these two neglected tropical diseases in seven more states. These exemplars of success should be studied and adapted to tackle the global climate-health challenge. The integrated, community-based approaches employed in the elimination of these diseases are best practices and further buttress the need to employ robust health-in-all-policies and multi-sectoral approaches to tackle the health impacts of climate change and eliminate disease.

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