Physical Durability of Two Types of Long-Lasting Insecticidal Nets (LLINs) Three Years After a Mass LLIN Distribution Campaign in Mozambique, 2008–2011

Abstract

Abstract. We conducted a prospective evaluation to measure the physical durability of two brands of long-lasting insecticidal nets (LLINs) distributed during a campaign in 2008 in Nampula Province, Mozambique. Households with LLINs tagged during the campaign (6,000) were geo-located (34%) and a random sample was selected for each of 3 years of follow-up. The LLINs were evaluated in the field and a laboratory for presence of holes and a proportional hole index (pHI) was calculated following the World Health Organization guidelines. We performed 567 interviews (79.0%) and found 75.3% (72.1-78.4%) of households retained at least one LLIN after 3 years; the most common cause of attrition was damage beyond repair (51.0%). Hole damage was evident after 1 year, and increased by year. Olyset had a significantly greater mean number of holes and pHI compared with PermaNet 2.0 brand (all P values 0.001). Additional information about LLIN durability is recommended to improve malaria control efforts.

Physical integrity and residual bio-efficacy of used LLINs in three cities of the South-West region of Cameroon 4 years after the first national mass-distribution campaign

“…Their effectiveness is improved by the addition of insecticide and they still provide some protection even torn [4]. Many countries have embarked in mass LLINs distribution campaigns [5–10]. However little information exists on the physical durability of LLINs in the field; and few malaria control programmes to date have systematically monitored the performance of LLINs in terms of physical durability after mass distributions [10].…”

“…Many countries have embarked in mass LLINs distribution campaigns [5–10]. However little information exists on the physical durability of LLINs in the field; and few malaria control programmes to date have systematically monitored the performance of LLINs in terms of physical durability after mass distributions [10]. Aside for net fabric [11] and fibre weight or denier [12], other factors that influence physical deterioration are the house environment (house wall material, bed type and construction), socio economic status (SES) and the bed net maintenance behaviour (general handling, washing and repair) [13, 14].…”

Evaluation de l’état physique et de l’efficacité biologique de deux types de moustiquaires imprégnées à longue durée d’action utilisés depuis 5 à 36 mois et collectés dans 11 districts du Sénégal

“…Le même constat a été rapporté dans des études menées en Ouganda et au Tchad qui ont montré respectivement que 45 à 78 % des moustiquaires en usage opérationnel étaient endommagées et que seulement 30 % étaient encore en bonne condition après une année d'utilisation [1,12]. À l'instar des études réalisées au Mozambique et au Bénin, nos résultats ont montré que la perte de l'intégrité physique variait selon la marque [18,20]. L'évaluation de l'efficacité biologique a révélé que les deux marques étudiées présentaient une bonne efficacité résiduelle, car induisant un taux important de KD.…”

Phase III evaluation of the insecticidal efficacy and durability of a deltamethrin-treated polypropylene long-lasting net LifeNet®, in comparison with long-lasting nets made from polyester and polyethylene: study protocol

“…LN durability is measured as a function of net survivorship, fabric integrity and insecticidal activity [4], which are all influenced by frequency of use, net care and repair, washing and maintenance practices, duration of transmission season [9–11], as well as the textile’s physical features, such as fibre material, knitting or weaving pattern, insecticide type and concentration, and fibre impregnation technology [12]. Average effective net life is often assumed to be 3 years [4] but can vary substantially between products [13, 14], endemic regions [15–19], and conditions of use [20]. …”