Large fluctuations in the effective population size of the malaria mosquito <i><scp>A</scp>nopheles gambiae s.s</i>. during vector control cycle

Hodges, Theresa K; Athrey, Giridhar; Deitz, Kevin C.; Overgaard, Hans J.; Matías, Abrahán; Caccone, Adalgisa; Slotman, Michel A.

doi:10.1111/eva.12094

Cited by 19 publications

(16 citation statements)

References 71 publications

(143 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Generation times derived from our curve-fitting procedure closely approximated prior empirical estimates. Assuming 25-year generations for primates, we estimated for P. falciparum and A. gambiae 2.08 and 17.5 generations/year, respectively (previously reported as 2 and 10-24 generations/year, respectively 10,19,20 ). Our findings support prior conclusions that forest clearing and agricultural settlements engendered growth in anopheline populations and intensified their role as vectors of malaria 21 .…”

supporting

confidence: 85%

Comparative demography elucidates the longevity of parasitic and symbiotic relationships

Hecht

Thompson

Rosenthal

2018

Preprint

View full text Add to dashboard Cite

Parasitic and symbiotic relationships govern vast nutrient and energy flows 1,2 , but controversy surrounds their longevity. Enduring relationships may engender parallel phylogenies among hosts and parasites 3,4 , but so may more ephemeral relationships when parasites disproportionately colonize related hosts 5 . When considering these relationships' temporal durability, it would be useful to understand whether parasite and host populations have grown and contracted in concert. Here, we devised methods to compare demographic histories, derived from genomic data 6 . We used these methods to compare the historical growth of the agent of severe human malaria, Plasmodium falciparum, to human and primate histories 7,8 and to that of their mosquito vector Anopheles gambiae 9 , thereby discerning long-term parallels and anthropogenic population explosions 10,11 . The growth history of Trichinella spiralis, a zoonotic parasite disseminated by swine domestication 12,13 , proved regionally-specific, paralleling distinctive growth histories for wild boar in Asia and Europe 14 . Parallel histories were inferred for an anemone and its algal symbiont (Aiptasia pallida 15 and Symbiodinium minutum 16 ). Concerted growth in potatoes and the agent of potato blight (Solanum tuberosum 17 and Phytophthora infestans 18 ) did not commence until the age of potato domestication, helping date the acquisition of this historically consequential fungal plant pathogen. Therefore, comparative historical demography provides a powerful new means by which to interrogate the history of myriad ecological relationships, enriching our understanding of their origins and durability.In order to examine the demographic history of individual species, we determined the extent and distribution of heterozygous positions called from high-quality genome assemblies. Each demographic history was then reconstructed using the pairwise sequentially Markovian

show abstract

supporting

confidence: 85%

Comparative demography elucidates the longevity of parasitic and symbiotic relationships

Hecht

Thompson

Rosenthal

2018

Preprint

View full text Add to dashboard Cite

show abstract

“…Previous genetic studies have aimed to detect seasonal bottlenecks in different populations of the A. gambiae species complex that undergo severe density depression during the DS or that have undergone vector control (Athrey et al, 2012;Hodges et al, 2013;Lehmann, Hawley, Grebert, & Collins, 1998;Simard et al, 2000;Taylor, Toure, Coluzzi, & Petrarca, 1993;Wondji, Simard, et al, 2005). The effective population size (N e ) approximates the number of breeding adults in a population if the population density is stable and parental contributions to the next generation are randomly distributed (Nei & Tajima, 1981;Waples, 1989).…”

Section: Introductionmentioning

confidence: 99%

Tracing the origin of the early wet‐season Anopheles coluzzii in the Sahel

Lehmann

Weetman

Huestis

et al. 2017

Evolutionary Applications

View full text Add to dashboard Cite

In arid environments, the source of the malaria mosquito populations that re‐establish soon after first rains remains a puzzle and alternative explanations have been proposed. Using genetic data, we evaluated whether the early rainy season (RS) population of Anopheles coluzzii is descended from the preceding late RS generation at the same locality, consistent with dry season (DS) dormancy (aestivation), or from migrants from distant locations. Distinct predictions derived from these two hypotheses were assessed, based on variation in 738 SNPs in eleven A. coluzzii samples, including seven samples spanning 2 years in a Sahelian village. As predicted by the “local origin under aestivation hypothesis,” temporal samples from the late RS and those collected after the first rain of the following RS were clustered together, while larger genetic distances were found among samples spanning the RS. Likewise, multilocus genotype composition of samples from the end of the RS was similar across samples until the following RS, unlike samples that spanned the RS. Consistent with reproductive arrest during the DS, no genetic drift was detected between samples taken over that period, despite encompassing extreme population minima, whereas it was detected between samples spanning the RS. Accordingly, the variance in allele frequency increased with time over the RS, but not over the DS. However, not all the results agreed with aestivation. Large genetic distances separated samples taken a year apart, and during the first year, within‐sample genetic diversity declined and increased back during the late RS, suggesting a bottleneck followed by migration. The decline of genetic diversity followed by a mass distribution of insecticide‐treated nets was accompanied by a reduced mosquito density and a rise in the mutation conferring resistance to pyrethroids, indicating a bottleneck due to insecticidal selection. Overall, our results support aestivation in A. coluzzii during the DS that is accompanied by long‐distance migration in the late RS.

show abstract

“…Abbreviations BIMEP: Bioko Island Malaria Elimination Project; NMCP: National Malaria Control Programme; MIS: malaria indicator survey; IRS: indoor residual spraying; LLIN: long-lasting insecticidal net; PR: parasite rate; HBR: human biting rate; EIR: entomological inoculation rate; RDT: rapid diagnostic test; IQR: interquartile range; 95CI: 95% con dence intervals. Individuals with history of off-island travel in the previous eight weeks were excluded from the MIS to allow for the confounding effects of malaria importation [9]. Malaria prevalence by age group.…”

Section: Discussionmentioning

confidence: 99%

Malaria outbreak in Riaba district, Bioko Island – Lessons learned

Guerra

Fuseini

Donfack

et al. 2020

Preprint

View full text Add to dashboard Cite

At the beginning of 2019, a sudden surge of malaria cases was observed in the district of Riaba, Bioko Island. Between January and April, confirmed malaria cases increased 3.8-fold compared to the same period in 2018. Concurrently, anopheline human biting rate (HBR) increased 2.1-fold. During the outbreak, 82.2% of the district population was tested for malaria with a rapid diagnostic test; 37.2% of those tested had a detectable infection and were treated according to national guidelines. Vector control interventions, including indoor residual spraying and larval source management were scaled-up. After the interventions, the number of confirmed cases decreased by 70% and the overall parasite prevalence in the communities by 43.8%. Observed prevalence in a follow up malaria indicator survey, however, was significantly higher than elsewhere on the island, and higher than in previous years. There was no significant reduction in HBR, which remained high for the rest of the year. The surge was attributed to various factors, chiefly increased rainfall and a large number of anthropogenic anopheline breeding sites created by construction works. This case study highlights the need for sustained vector control interventions and multi-sector participation, particularly in malaria control and elimination settings with persistently high local malaria receptivity.

show abstract

Large fluctuations in the effective population size of the malaria mosquito Anopheles gambiae s.s. during vector control cycle

Cited by 19 publications

References 71 publications

Comparative demography elucidates the longevity of parasitic and symbiotic relationships

Comparative demography elucidates the longevity of parasitic and symbiotic relationships

Tracing the origin of the early wet‐season Anopheles coluzzii in the Sahel

Malaria outbreak in Riaba district, Bioko Island – Lessons learned

Contact Info

Product

Resources

About