scholarly journals Temperature explains broad patterns of Ross River virus transmission across Australia

2018 ◽  
Author(s):  
Marta S. Shocket ◽  
Sadie J. Ryan ◽  
Erin A. Mordecai
Keyword(s):  
Disease Transmission ◽  
Pacific Islands ◽  
Mechanistic Model ◽  
Empirical Relationship ◽  
Virus Transmission ◽  
Thermal Response ◽  
Nonlinear Effects ◽  
Ross River Virus ◽  
The Pacific ◽  
The Tropics

ABSTRACTTemperature impacts the physiology of ectotherms, including vectors that transmit disease. While thermal biology predicts nonlinear effects of temperature on vector and pathogen traits that drive disease transmission, the empirical relationship between temperature and transmission remains unknown for most vector-borne pathogens. We built a mechanistic model to estimate the thermal response of Ross River virus, an important mosquito-borne pathogen of humans in Australia, the Pacific Islands, and potentially emerging worldwide. Transmission peaks at moderate temperatures (26.4°C) and declines to zero at low (17.0°C) and high (31.5°C) temperatures. The model predicted broad patterns of disease across Australia. First, transmission is year-round endemic in the tropics and sub-tropics but seasonal in temperate zones. Second, nationwide human cases peak seasonally as predicted from population-weighted seasonal temperatures. These results illustrate the importance of nonlinear, mechanistic models for inferring the role of temperature in disease dynamics and predicting responses to climate change.

scholarly journals Temperature explains broad patterns of Ross River virus transmission

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Marta Strecker Shocket ◽  
Sadie J Ryan ◽  
Erin A Mordecai
Keyword(s):  
Disease Transmission ◽  
Pacific Islands ◽  
Nonlinear Models ◽  
Mechanistic Model ◽  
Virus Transmission ◽  
Thermal Response ◽  
Ross River Virus ◽  
Vector Borne ◽  
High And Low Temperatures ◽  
The Tropics

Thermal biology predicts that vector-borne disease transmission peaks at intermediate temperatures and declines at high and low temperatures. However, thermal optima and limits remain unknown for most vector-borne pathogens. We built a mechanistic model for the thermal response of Ross River virus, an important mosquito-borne pathogen in Australia, Pacific Islands, and potentially at risk of emerging worldwide. Transmission peaks at moderate temperatures (26.4°C) and declines to zero at thermal limits (17.0 and 31.5°C). The model accurately predicts that transmission is year-round endemic in the tropics but seasonal in temperate areas, resulting in the nationwide seasonal peak in human cases. Climate warming will likely increase transmission in temperate areas (where most Australians live) but decrease transmission in tropical areas where mean temperatures are already near the thermal optimum. These results illustrate the importance of nonlinear models for inferring the role of temperature in disease dynamics and predicting responses to climate change.

Systematics, Biogeography, and Morphological Character Evolution of the Hemiepiphytic Subfamily Monsteroideae (Araceae)

2019 ◽  
Vol 104 (1) ◽  
pp. 33-48 ◽  
Author(s):  
Alejandro Zuluaga ◽  
Martin Llano ◽  
Ken Cameron
Keyword(s):  
Dna Sequences ◽  
Pacific Islands ◽  
R Package ◽  
Morphological Characters ◽  
Ancestral State ◽  
Seed Shape ◽  
Long Distance ◽  
The Pacific ◽  
And Migration ◽  
The Tropics

The subfamily Monsteroideae (Araceae) is the third richest clade in the family, with ca. 369 described species and ca. 700 estimated. It comprises mostly hemiepiphytic or epiphytic plants restricted to the tropics, with three intercontinental disjunctions. Using a dataset representing all 12 genera in Monsteroideae (126 taxa), and five plastid and two nuclear markers, we studied the systematics and historical biogeography of the group. We found high support for the monophyly of the three major clades (Spathiphylleae sister to Heteropsis Kunth and Rhaphidophora Hassk. clades), and for six of the genera within Monsteroideae. However, we found low rates of variation in the DNA sequences used and a lack of molecular markers suitable for species-level phylogenies in the group. We also performed ancestral state reconstruction of some morphological characters traditionally used for genera delimitation. Only seed shape and size, number of seeds, number of locules, and presence of endosperm showed utility in the classification of genera in Monsteroideae. We estimated ancestral ranges using a dispersal-extinction-cladogenesis model as implemented in the R package BioGeoBEARS and found evidence for a Gondwanan origin of the clade. One tropical disjunction (Monstera Adans. sister to Amydrium Schott–Epipremnum Schott) was found to be the product of a previous Boreotropical distribution. Two other disjunctions are more recent and likely due to long-distance dispersal: Spathiphyllum Schott (with Holochlamys Engl. nested within) represents a dispersal from South America to the Pacific Islands in Southeast Asia, and Rhaphidophora represents a dispersal from Asia to Africa. Future studies based on stronger phylogenetic reconstructions and complete morphological datasets are needed to explore the details of speciation and migration within and among areas in Asia.

scholarly journals The Orchids of Tonga, Niue, and the Cook Islands

Lankesteriana ◽  
2011 ◽  
Vol 11 (2) ◽  
Author(s):  
Phillip Cribb ◽  
Arthur Whistler
Keyword(s):  
Pacific Islands ◽  
Solomon Islands ◽  
New Guinea ◽  
Cook Islands ◽  
Society Islands ◽  
Present Book ◽  
The Pacific ◽  
The World ◽  
The Tropics ◽  
Pacific Species

Orchids are one of the largest families of flowering plants in the Pacific region, especially in the tropics. Despite the remoteness of Tonga, Niue, and the Cook Islands, orchids have reached them in some numbers. Both terrestrial and epiphytic genera are well represented in the floras of these distant but neighboring archipelagos. Most of the species are found elsewhere in the Pacific, particularly in Fiji, Samoa, and the Society Islands. The affinities of these orchids can be traced to New Guinea and the adjacent archipelagos. New Guinea, with an estimated 3000 species that make it one of the richest orchid floras in the world, is a fertile source of seed for the scattered islands that lie to its east and southeast. The orchids appear to have reached Tonga, Niue, and the Cook Islands in recent times. Only two species, Habenaria amplifolia from Rarotonga and Robiquetia tongaensis from Tonga, are endemic to the islands covered in the present book, and both are closely related to more widespread Pacific species. This guide constitutes the fourth of a series of orchid floristic treatments that have so far covered Vanuatu (Lewis & Cribb 1989), the Solomon Islands and Bougainville (Lewis & Cribb 1991), and Samoa (Cribb & Whistler 1996). A recent, excellent and detailed account of the Fijian orchid flora (Kores 1991) has also been a valuable source for those interested in Pacific islands orchids. These accounts have generated renewed interest in the orchid floras of those archipelagos, leading to new discoveries and re-interpretations of several species. We hope that this small guide will likewise bring a renewal of interest in not only the orchids, but also the floras of these islands as a whole. 

scholarly journals Geographic Distribution and Evolution of Ross River Virus in Australia and the Pacific Islands

Virology ◽  
1995 ◽  
Vol 212 (1) ◽  
pp. 20-29 ◽  
Author(s):  
Leanne M. Sammels ◽  
Robert J. Coelen ◽  
Michael D. Lindsay ◽  
John S. Mackenzie
Keyword(s):  
Geographic Distribution ◽  
Pacific Islands ◽  
Ross River Virus ◽  
The Pacific

scholarly journals New evidence for endemic circulation of Ross River virus in the Pacific Islands and the potential for emergence

2017 ◽  
Vol 57 ◽  
pp. 73-76 ◽  
Author(s):  
Colleen Lau ◽  
Maite Aubry ◽  
Didier Musso ◽  
Anita Teissier ◽  
Sylvie Paulous ◽  
...  
Keyword(s):  
Pacific Islands ◽  
Ross River Virus ◽  
The Pacific ◽  
New Evidence

scholarly journals Structure in the variability of the basic reproductive number (R0) for Zika epidemics in the Pacific islands

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Clara Champagne ◽  
David Georges Salthouse ◽  
Richard Paul ◽  
Van-Mai Cao-Lormeau ◽  
Benjamin Roche ◽  
...  
Keyword(s):  
Pacific Islands ◽  
New Caledonia ◽  
Control Strategies ◽  
Virus Transmission ◽  
French Polynesia ◽  
Basic Reproductive Number ◽  
Effective Control ◽  
Reproductive Number ◽  
The Pacific ◽  
Seroprevalence Data

Before the outbreak that reached the Americas in 2015, Zika virus (ZIKV) circulated in Asia and the Pacific: these past epidemics can be highly informative on the key parameters driving virus transmission, such as the basic reproduction number (R0). We compare two compartmental models with different mosquito representations, using surveillance and seroprevalence data for several ZIKV outbreaks in Pacific islands (Yap, Micronesia 2007, Tahiti and Moorea, French Polynesia 2013-2014, New Caledonia 2014). Models are estimated in a stochastic framework with recent Bayesian techniques. R0 for the Pacific ZIKV epidemics is estimated between 1.5 and 4.1, the smallest islands displaying higher and more variable values. This relatively low range of R0 suggests that intervention strategies developed for other flaviviruses should enable as, if not more effective control of ZIKV. Our study also highlights the importance of seroprevalence data for precise quantitative analysis of pathogen propagation, to design prevention and control strategies.

scholarly journals Tropical Island Imaginary

2016 ◽  
Vol 12 (2) ◽  
Author(s):  
Stephen Torre
Keyword(s):  
Human Nature ◽  
Pacific Islands ◽  
Historical Survey ◽  
Tropical Islands ◽  
Tropical Island ◽  
Western Literature ◽  
Truth Claim ◽  
The Pacific ◽  
Tropical Australia ◽  
The Tropics

This paper opens with a historical survey of the imaginary representation of islands in Western literature and then proceeds to a selective account of the island imaginary in largely ‘middlebrow’ writings and photography about the tropics. Complexities and paradoxes in the significances and semiotics of islands can be found in much writing about the Pacific islands of tropical Australia. E.J.Banfield largely established the paradisal perspective on tropical islands and extolled the lifestyle of the ‘beachcomber’. The often challenged ‘truth claim’ that ‘the camera cannot lie’ is most pertinent to Hurley’s work: what we see there is not only a speculum but more often a spectacle of the island imaginary; indeed the staging and replication of content so as to reflect what Hurley wanted to see in his subjects amounts to the substitution of a hyperreal, which then establishes itself in the discourse of the tropical island imaginary. Norman Lindsay tapped into some persistent motifs of the island imaginary: the excitement created by shipwreck and survival; the romance and salacious possibilities afforded by the attractions between a heroine and her suitors; and the realities of human nature stripped of civilised manners. Paradoxically, the popular works of Ion L. Idriess problematize the boundaries between material fact and textual discourse, tapping into what may well be a paradigm for the island imaginary in general—a space where contraries multiply and fantasies materialize. Lastly, Frank Clune’s ‘counterfeit adventures’ similarly play around persistent binaries and stereotypes in the island imaginary, and perpetuate a reification of the complexity and elusiveness of their subject.

scholarly journals Structure in the variability of the basic reproductive number (R0) for Zika epidemics in the Pacific islands

2016 ◽  
Author(s):  
Clara Champagne ◽  
David Georges Salthouse ◽  
Richard Paul ◽  
Van-Mai Cao-Lormeau ◽  
Benjamin Roche ◽  
...  
Keyword(s):  
Pacific Islands ◽  
New Caledonia ◽  
Control Strategies ◽  
Virus Transmission ◽  
French Polynesia ◽  
Basic Reproductive Number ◽  
Effective Control ◽  
Reproductive Number ◽  
The Pacific ◽  
Seroprevalence Data

AbstractBefore the outbreak that reached the Americas in 2015, Zika virus (ZIKV) circulated in Asia and the Pacific: these past epidemics can be highly informative on the key parameters driving virus transmission, such as the basic reproduction number (R0). We compare two compartmental models with different mosquito representations, using surveillance and seroprevalence data for several ZIKV outbreaks in Pacific islands (Yap, Micronesia 2007, Tahiti and Moorea, French Polynesia 2013-2014, New Caledonia 2014). Models are estimated in a stochastic framework with state-of-the-art Bayesian techniques. R0 for the Pacific ZIKV epidemics is estimated between 1.5 and 4.1, the smallest islands displaying higher and more variable values. This relatively low range of R0 suggests that intervention strategies developed for other flaviviruses should enable as, if not more effective control of ZIKV. Our study also highlights the importance of seroprevalence data for precise quantitative analysis of pathogen propagation, to design prevention and control strategies.

Sign in / Sign up

Export Citation Format

Share Document