Genome structural variants shape adaptive success of an invasive urban malaria vector .

Global changes are associated with the emergence of several invasive species. However, the genomic determinants of the adaptive success of an invasive species in a new environment remain poorly understood. Genomic structural variants (SVs), consisting of copy number variants, play an important role in adaptation.

Wastewater-based surveillance of vector-borne pathogens: a cautionary note.

Diamond et al. recently identified malaria and dengue as high-priority diseases in wastewater surveillance for climate-change-driven shifts in pathogen dynamics. When employing wastewater surveillance for vector-borne pathogens it is essential to take into account the geographical context, pathogen biology, and the availability of sewage networks for meaningful interventions.

Determinants of Aedes mosquito larval ecology in a heterogeneous urban environment- a longitudinal study in Bengaluru, India.

Background: Aedes-borne disease risk is associated with contemporary urbanization practices where city developing structures function as a catalyst for creating mosquito breeding habitats. We lack better understanding on how the links between landscape ecology and urban geography contribute to the prevalence and abundance of mosquito and pathogen spread.

Methods: An outdoor longitudinal study in Bengaluru (Karnataka, India) was conducted between February 2021 and June 2022 to examine the effects of macrohabitat types on the diversity and distribution of larval habitats, mosquito species composition, and body size to quantify the risk of dengue outbreak in the landscape context.

SARS-CoV-2 infection dynamics and genomic surveillance to detect variants in wastewater - a longitudinal study in Bengaluru, India.

Background: Environmental surveillance (ES) of a pathogen is crucial for understanding the community load of disease. As an early warning system, ES for SARS-CoV-2 has complemented routine diagnostic surveillance by capturing near real-time virus circulation at a population level.

Methods: In this longitudinal study conducted between January 2022 and June 2022 in 28 sewershed sites in Bengaluru city (∼11 million inhabitants), we quantified weekly SARS-CoV-2 RNA concentrations to track infection dynamics and provide evidence of change in the relative abundance of emerging variants.

Exploring the thermal limits of malaria transmission in the western Himalaya.

Environmental temperature is a key driver of malaria transmission dynamics. Using detailed temperature records from four sites: low elevation (1800), mid elevation (2200 m), and high elevation (2600-3200 m) in the western Himalaya, we model how temperature regulates parasite development rate (the inverse of the extrinsic incubation period, EIP) in the wild. Using a Briére parametrization of the EIP, combined with Bayesian parameter inference, we study the thermal limits of transmission for avian () and human parasites ( and ) as well as for two malaria-like avian parasites, and .

Island biogeography and human practices drive ecological connectivity in mosquito species richness in the Lakshadweep Archipelago.

Mosquitoes are globally distributed and adapted to a broad range of environmental conditions. As obligatory hosts of many infectious pathogens, mosquito abundance and distribution are primarily determined by the presence and quality of larval habitats. To understand the dynamics and productivity of larval habitats in changing island environments, we conducted a four-month mosquito survey across ten inhabited islands in the Lakshadweep archipelago.

Genetic drift and bottleneck do not influence diversity in Toll-like receptor genes at a small spatial scale in a Himalayan passerine.

Genetic diversity is important for long-term viability of a population. Low genetic diversity reduces persistence and survival of populations and increases susceptibility to diseases. Comparisons of the neutral markers with functional loci such as immune genes [Toll-like receptors; TLR] can provide useful insights into evolutionary potential of a species and how the diversity of pathogens and selection pressures on their hosts are directly linked to their environment.

Misperceived Risks of Zika-related Microcephaly in India.

After the discovery that Zika virus (ZIKV) could cause microcephaly and other birth defects, we have scrambled to understand how. Now, spreading along with the virus is misinformation that a ZIKV mutation is responsible for microcephaly. Putting too much onus on a single mutation could enhance a crisis in India.

Noninvasive sampling reveals population genetic structure in the Royle's pika, , in the western Himalaya.

Understanding population genetic structure of climate-sensitive herbivore species is important as it provides useful insights on how shifts in environmental conditions can alter their distribution and abundance. Herbivore responses to the environment can have a strong indirect cascading effect on community structure. This is particularly important for Royle's pika (Lagomorpha: ), a herbivorous talus-dwelling species in alpine ecosystem, which forms a major prey base for many carnivores in the Himalayan arc.

Molecular characterization and morphological description of cryptic haemoproteids in the laughingthrushes (Leiothrichidae) in the western and eastern Himalaya, India.

Laughingthrushes (family: Leiothrichidae) consists of diverse and widespread species found in the Indian subcontinent but there is a lack of information on their avian haemosporidians.  : We sampled 231 laughingthrushes of 8 species in the western and eastern Himalaya in India. Using parasite morphology and cytochrome sequences we describe 2 new species harbored in 3 species of laughingthrushes and report a case of cryptic speciation.

A diet rich in C plants reveals the sensitivity of an alpine mammal to climate change.

Plant-herbivore interactions provide critical insights into the mechanisms that govern the spatiotemporal distributions of organisms. These interactions are crucial to understanding the impacts of climate change, which are likely to have an effect on the population dynamics of alpine herbivores. The Royle's pika (Ochotona roylei, hereafter pika) is a lagomorph found in the western Himalaya and is dependent on alpine plants that are at risk from climate change.

Exploring host and geographical shifts in transmission of haemosporidians in a Palaearctic passerine wintering in India.

This is the first molecular study of avian haemosporidia diversity in wintering populations of the Blyth's Reed Warbler () in India that explores the extent of host and geographical shifts in transmission areas. In 156 birds, six lineages (37.8%; 95% CI 30.

Do avian blood parasites influence hypoxia physiology in a high elevation environment?

Background: Montane birds which engage in elevational movements have evolved to cope with fluctuations in environmental hypoxia, through changes in physiological parameters associated with blood oxygen-carrying capacity such as haemoglobin concentration (Hb) and haematocrit (Hct). In particular, elevational migrants which winter at low elevations, encounter varying intensities of avian haemosporidian parasites as they traverse heterogeneous environments. Whilst high intensity parasite infections lead to anaemia, one can expect that the ability to cope with haemosporidian infections should be a key trait for elevational migrants that must be balanced against reducing the oxygen-carrying capacity of blood in response to high elevation.

A Call to Introduce Structured Zika Surveillance in India.

India has the climatic conditions conducive to year-round transmission of Zika virus, and a structured disease surveillance program should be implemented to prevent an outbreak. Such a program should (i) start screening before an outbreak arises; (ii) collect baseline data to assess future disease risk and monitor potential birth defects; and (iii) provide new insights into the ecology of the disease and inform public health policy following the one health concept.

Seasonal dynamics in mosquito abundance and temperature do not influence avian malaria prevalence in the Himalayan foothills.

We examined seasonal prevalence in avian haemosporidians ( and ) in migrant and resident birds in western Himalaya, India. We investigated how infection with haemosporidians in avian hosts is associated with temporal changes in temperature and mosquito abundance along with host abundance and life-history traits (body mass). Using molecular methods for parasite detection and sequencing partial cytochrome gene, 12 and 27 lineages were isolated.

Estimating prevalence of avian haemosporidians in natural populations: a comparative study on screening protocols.

Background: Birds harbour an astonishing diversity of haemosporidian parasites. Renewed interest in avian haemosporidians as a model system has placed a greater emphasis on the development of screening protocols to estimate parasite prevalence and diversity. Prevalence estimates are often based on the molecular or blood-smear microscopy techniques.

Specialist enemies, generalist weapons and the potential spread of exotic pathogens: malaria parasites in a highly invasive bird.

Pathogens can influence the success of invaders. The Enemy Release Hypothesis predicts invaders encounter reduced pathogen abundance and diversity, while the Novel Weapons Hypothesis predicts invaders carry novel pathogens that spill over to competitors. We tested these hypotheses using avian malaria (haemosporidian) infections in the invasive myna (Acridotheres tristis), which was introduced to southeastern Australia from India and was secondarily expanded to the eastern Australian coast.

Differences in host species relationships and biogeographic influences produce contrasting patterns of prevalence, community composition and genetic structure in two genera of avian malaria parasites in southern Melanesia.

Host-parasite interactions have the potential to influence broadscale ecological and evolutionary processes, levels of endemism, divergence patterns and distributions in host populations. Understanding the mechanisms involved requires identification of the factors that shape parasite distribution and prevalence. A lack of comparative information on community-level host-parasite associations limits our understanding of the role of parasites in host population divergence processes.

Niche filling slows the diversification of Himalayan songbirds.

Speciation generally involves a three-step process--range expansion, range fragmentation and the development of reproductive isolation between spatially separated populations. Speciation relies on cycling through these three steps and each may limit the rate at which new species form. We estimate phylogenetic relationships among all Himalayan songbirds to ask whether the development of reproductive isolation and ecological competition, both factors that limit range expansions, set an ultimate limit on speciation.

Antibodies to influenza A virus in wild birds across Mongolia, 2006-2009.

Wild waterbirds sampled July 2006-September 2009 in Mongolia were tested for antibodies to avian influenza (AI) virus with the use of a commercially available blocking enzyme-linked immunosorbent assay. Antibodies were detected in 25% (572/2,282) of tested birds representing 26 species, and all antibody-positive samples were from 12 species in the orders Anseriformes and Charadriiformes. The highest antibody prevalence was in Ruddy Shelducks (Tadorna ferruginea; 61.

Diversity and distribution of avian haematozoan parasites in the western Indian Ocean region: a molecular survey.

The genetic diversity of haematozoan parasites in island avifauna has only recently begun to be explored, despite the potential insight that these data can provide into the history of association between hosts and parasites and the possible threat posed to island endemics. We used mitochondrial DNA sequencing to characterize the diversity of 2 genera of vector-mediated parasites (Plasmodium and Haemoproteus) in avian blood samples from the western Indian Ocean region and explored their relationship with parasites from continental Africa. We detected infections in 68 out of 150 (45·3%) individuals and cytochrome b sequences identified 9 genetically distinct lineages of Plasmodium spp.

Host associations and evolutionary relationships of avian blood parasites from West Africa.

The host specificity of blood parasites recovered from a survey of 527 birds in Cameroon and Gabon was examined at several levels within an evolutionary framework. Unique mitochondrial lineages of Haemoproteus were recovered from an average of 1.3 host species (maximum=3) and 1.

Prevalence and diversity of avian hematozoan parasites in Asia: a regional survey.

Tissue samples from 699 birds from three regions of Asia (Myanmar, India, and South Korea) were screened for evidence of infection by avian parasites in the genera Plasmodium and Haemoproteus. Samples were collected from November 1994 to October 2004. We identified 241 infected birds (34.

Global phylogeographic limits of Hawaii's avian malaria.

The introduction of avian malaria (Plasmodium relictum) to Hawaii has provided a model system for studying the influence of exotic disease on naive host populations. Little is known, however, about the origin or the genetic variation of Hawaii's malaria and traditional classification methods have confounded attempts to place the parasite within a global ecological and evolutionary context. Using fragments of the parasite mitochondrial gene cytochrome b and the nuclear gene dihydrofolate reductase-thymidylate synthase obtained from a global survey of greater than 13000 avian samples, we show that Hawaii's avian malaria, which can cause high mortality and is a major limiting factor for many species of native passerines, represents just one of the numerous lineages composing the morphological parasite species.