Is mass drug administration against lymphatic filariasis required in urban settings? The experience in Kano, Nigeria

• Published in: PLoS neglected tropical diseases 2017-10, Vol.11 (10), p.e0006004-e0006004
• Main Authors: Pam, Dung D, de Souza, Dziedzom K, D'Souza, Susan, Opoku, Millicent, Sanda, Safiya, Nazaradden, Ibrahim, Anagbogu, Ifeoma N, Okoronkwo, Chukwu, Davies, Emmanuel, Elhassan, Elisabeth, Molyneux, David H, Bockarie, Moses J, Koudou, Benjamin G
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Animals; Anopheles - parasitology; Antigens; Antigens, Helminth - blood; Antigens, Helminth - genetics; Aquatic insects; Biology and Life Sciences; Blood; Child; Children; Chronic illnesses; Collections; Control; Culex; Culex - parasitology; Culicidae; Deoxyribonucleic acid; Detection; Diagnosis; Disease; Disease Eradication - methods; Dissection; DNA; Drug Administration Schedule; Drugs; Earth Sciences; Elephantiasis, Filarial - drug therapy; Elephantiasis, Filarial - epidemiology; Elephantiasis, Filarial - prevention & control; Elephantiasis, Filarial - transmission; Epidemiology; Female; Filariasis; Filaricides - administration & dosage; Funding; Genetic aspects; Households; Humans; Infections; Local government; Male; Medical research; Medicine; Medicine and Health Sciences; Middle Aged; Morbidity; Mosquitoes; Nigeria - epidemiology; Nucleotide sequence; Parasites; Parasitology; PCR; People and Places; Polymerase Chain Reaction; Populations; Prevalence studies (Epidemiology); Public health; Research and Analysis Methods; Risk factors; Rural communities; Transmission; Traps; Trends; Tropical diseases; Urban areas; Urban environments; Urban Health; Urban populations; Vector-borne diseases; Wuchereria bancrofti; Wuchereria bancrofti - genetics; Wuchereria bancrofti - isolation & purification; Young Adult
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0006004

The Global Programme to Eliminate Lymphatic Filariasis (GPELF), launched in 2000, has the target of eliminating the disease as a public health problem by the year 2020. The strategy adopted is mass drug administration (MDA) to all eligible individuals in endemic communities and the implementation of measures to reduce the morbidity of those suffering from chronic disease. Success has been recorded in many rural endemic communities in which elimination efforts have centered. However, implementation has been challenging in several urban African cities. The large cities of West Africa, exemplified in Nigeria in Kano are challenging for LF elimination program because reaching 65% therapeutic coverage during MDA is difficult. There is therefore a need to define a strategy which could complement MDA. Thus, in Kano State, Nigeria, while LF MDA had reached 33 of the 44 Local Government Areas (LGAs) there remained eleven 'urban' LGAs which had not been covered by MDA. Given the challenges of achieving at least 65% coverage during MDA implementation over several years in order to achieve elimination, it may be challenging to eliminate LF in such settings. In order to plan the LF control activities, this study was undertaken to confirm the LF infection prevalence in the human and mosquito populations in three urban LGAs. The prevalence of circulating filarial antigen (CFA) of Wuchereria bancrofti was assessed by an immuno-chromatography test (ICT) in 981 people in three urban LGAs of Kano state, Nigeria. Mosquitoes were collected over a period of 4 months from May to August 2015 using exit traps, gravid traps and pyrethrum knock-down spray sheet collections (PSC) in different households. A proportion of mosquitoes were analyzed for W. bancrofti, using dissection, loop-mediated isothermal amplification (LAMP) assay and conventional polymerase chain reaction (PCR). The results showed that none of the 981 subjects (constituted of