Complex genome evolution in Anopheles coluzzii associated with increased insecticide usage in Mali.

In certain cases, a species may have access to important genetic variation present in a related species via adaptive introgression. These novel alleles may interact with their new genetic background, resulting in unexpected phenotypes. In this study, we describe a selective sweep on standing variation on the X chromosome in the mosquito Anopheles coluzzii, a principal malaria vector in West Africa. This event may have been influenced by the recent adaptive introgression of the insecticide resistance gene known as kdr from the sister species Anopheles gambiae. Individuals carrying both kdr and a nearly fixed X-linked haplotype, encompassing at least four genes including the P450 gene CYP9K1 and the cuticular protein CPR125, have rapidly increased in relative frequency. In parallel, a reproductively isolated insecticide-susceptible A. gambiae population (Bamako form) has been driven to local extinction, likely due to strong selection from increased insecticide-treated bed net usage

Comparing efficacy of a sweep net and a dip method for collection of mosquito larvae in large bodies of water in South Africa [version 1; referees : 2 approved]

In this study we tested an alternative method for collecting mosquito larvae called the sweep net catch method and compared its efficiency to that of the traditional dip method. The two methods were compared in various water bodies within Kruger National Park and Lapalala Wilderness area, South Africa. The sweep net catch method performed 5 times better in the collection of Anopheles larvae and equally as well as the dip method in the collection of Culex larvae (p =8.58 x 10 ). Based on 15 replicates the collector’s experience level did not play a significant role in the relative numbers of larvae collected using either method. This simple and effective sweep net catch method will greatly improve the mosquito larval sampling capacity in the field setting.Supplementary material: Larval rearing methods.Both Cornel and Braack were beneficiaries of a Carnegie African Diaspora Fellowship Program grant (IIE Grantee ID: 15410201) which partly enabled this study.http://f1000.com/reportsam2017UP Centre for Sustainable Malaria Control (UP CSMC

Anopheles darlingi polytene chromosomes: Revised maps including newly described inversions and evidence for population structure in Manaus

Salivary gland polytene chromosomes of 4th instar Anopheles darlingi Root were examined from multiple locations in the Brazilian Amazon. Minor modifications were made to existing polytene photomaps. These included changes to the breakpoint positions of several previously described paracentric inversions and descriptions of four new paracentric inversions, two on the right arm of chromosome 3 and two on the left arm of chromosome 3 that were found in multiple locations. A total of 18 inversions on the X (n = 1) chromosome, chromosome 2 (n = 7) and 3 (n = 11) were scored for 83 individuals from Manaus, Macapá and Porto Velho municipalities. The frequency of 2Ra inversion karyotypes in Manaus shows significant deficiency of heterozygotes (p < 0.0009). No significant linkage disequilibrium was found between inversions on chromosome 2 and 3. We hypothesize that at least two sympatric subpopulations exist within the An. darlingi population at Manaus based on inversion frequencies. © Instituto Oswaldo Cruz - Fundação Oswaldo Cruz - Ministério da Saúde 2016

Prospective predictors of actual research participation among African-American adults

Aim Although several variables appear to be associated with reluctance of African Americans to participate in research, most research on this topic has utilized hypothetical study scenarios, and there is a need for empirical studies of factors that predict actual study participation. The purpose of the present paper was to assess five potential predictors of participation in an actual study of psychological stress and health. Subjects and methods African American adults (n = 236) completed the Barriers to Research Participation Questionnaire (BRPQ), which assesses attitudes toward research participation, and indicated whether they were willing to be contacted for involvement in a study of psychological stress and health. Results Respondents who declined to be contacted for further involvement (n = 191) scored significantly lower (less willingness/greater barriers) on the overall BRPQ, and on the health beliefs/fears, role overload/time demands, and perceived benefits subscales than respondents who were enrolled in the study (n = 45). Conclusion Investigators might enhance enrollment of African American adults by ameliorating health-related fears, increasing accessibility, or communicating benefits of the research

Comparing efficacy of a sweep net and a dip method for collection of mosquito larvae in large bodies of water in South Africa

In this study we tested an alternative method for collecting mosquito larvae called the sweep net catch method and compared its efficiency to that of the traditional dip method. The two methods were compared in various water bodies within Kruger National Park and Lapalala Wilderness area, South Africa. The sweep net catch method performed 5 times better in the collection of Anopheles larvae and equally as well as the dip method in the collection of Culex larvae (p =8.58 x 10 -5). Based on 15 replicates the collector's experience level did not play a significant role in the relative numbers of larvae collected using either method. This simple and effective sweep net catch method will greatly improve the mosquito larval sampling capacity in the field setting

Raw larval collection data for all 15 replicates, including the relative abundance of Anopheles and Culex collected and the estimated time taken to collect one larva for each replicate.

Includes: trial location, trap type, trap handler,  number of mosquitoes collected, proportions of mosquitoes collected and estimated total time

Visual representation of both the sweep net catch and dip larval collection methods as performed by Braack and Cornel.

The SNC method can be seen in the first half of this video (0:04 - 1:20 minutes) while the Dip method can be seen in the second half (1:21 - 2:23 minutes)