Anti-feeding and insecticidal efficacy of a topical administration of dinotefuran-pyriproxyfen-permethrin spot-on (Vectra® 3D) on mice against Stegomyia albopicta (= Aedes albopictus).

An ectoparasiticide combining three active ingredients [dinotefuran, permethrin and pyriproxyfen (DPP)] was used in mice in an experiment designed to evaluate its anti-feeding and insecticidal efficacy against Stegomyia albopicta (= Aedes albopictus) (Diptera: Culicidae) mosquitoes. Twenty-two adult mice were randomly allocated into two groups consisting of an untreated control group and a DPP-treated group. Mice were exposed individually for 1 h to a mean ± standard deviation of 27 ± 2 starved female mosquitoes on days 1, 7, 14, 21 and 28 post-treatment. At the end of the exposure (1 h), mosquitoes were assessed for immediate survival and engorgement status. Additionally, live mosquitoes in both groups were incubated separately and observed for mortality at 24 h after the end of the exposure. The anti-feeding efficacy of DPP after the 1-h exposure period was 99.2, 100, 98.0, 89.3 and 87.4% at 1, 7, 14, 21 and 28 days, respectively. Levels of insecticidal efficacy evaluated at 1 h and 24 h after exposure on days 1, 7, 14, 21 and 28 were 36.7, 28.9, 30.8, 23.1 and 11.9%, and 68.4, 45.0, 43.3, 37.9 and 19.9%, respectively. Based on the mouse model, the present study demonstrates that the DPP combination has significant anti-feeding and insecticidal efficacy against S. albopicta for at least 4 weeks.

Assessment of the anti-feeding and insecticidal effects of the combination of dinotefuran, permethrin and pyriproxyfen (Vectra® 3D) against Triatoma infestans on rats.

This study, based on the rat model, was designed to explore the anti-feeding and insecticidal efficacy of a topical ectoparasiticide, dinotefuran-permethrin-pyriproxyfen (DPP), against Triatoma infestans (Hemiptera: Reduviidae), a vector of Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae), for which dogs are domestic reservoir hosts. Twenty rats were divided into two equal groups: untreated and treated. Each rat was exposed under sedation to 16 T. infestans of mixed life stages for 1 h on days 1, 7, 14, 21 and 28 post-treatment. The anti-feeding and insecticidal effects of DPP were estimated after 1 h of exposure. Insecticidal efficacy was also assessed after incubation of the insects for 24 h post-exposure. Anti-feeding efficacy was 96.7, 84.7, 80.5, 81.5 and 42.6% on days 1, 7, 14, 21 and 28, respectively. Insecticidal efficacy evaluated at 1 and 24 h after exposure on days 1, 7, 14, 21 and 28 was 100, 91.2, 82.5, 80.0 and 29.1, and 100, 100, 100, 96.0 and 49.9%, respectively. This study demonstrates that a single administration of DPP spot-on treatment at a dose equivalent to the minimal recommended dose in rats has a powerful effect against T. infestans starting from day 1 that lasts for at least 3 weeks.

Genotyping of Coxiella burnetii detected in placental tissues from aborted dairy cattle in the north of Algeria.

Coxiella burnetii, is an obligate intracellular bacterium which is present throughout the world. In humans, C. burnetii is the causative agent of Q fever. In cattle, the infection is suspected to cause stillbirths, retained fetal membranes, metritis and infertility. The birth products of ruminants shed huge amounts of bacteria, and are considered a major source for human infection. The present study was designed to search for the presence of C. burnetii in placental tissues collected from aborted and normal calving dairy cows in Algeria, using molecular tools. A total of 77 placental tissue fragments were collected from dairy cows. 73 samples were collected from aborted cows and four samples were collected from natural calving cows over a period of two years from January 2013 to March 2015. The presence of C. burnetii in these samples was screened by quantitative real-time polymerase chain reaction (qPCR) targeting two different genes, IS1111 and IS30 A. The positive PCR amplicons were subsequently sequenced for Multispacer Sequence Typing determination (MST) using seven pairs of sequences (Cox2, Cox5, Cox18, Cox37, Cox56, Cox57, and Cox61). Fourteen placental tissues (19.1%) were found to be positive for C. burnetii by qPCR; 9 (12.3%) from the city of Blida and 5 (6.84%) from the city of Medea. Genotyping of the corresponding amplicons displayed 100% identity with C. burnetii MST20 genotype, confirming the circulation of this clone in dairy farms from Algeria.