Ilya Fischhoff

• PhD
• American Association for the Advancement of Science

Understanding where and when pathogens occur in the environment has implications for reservoir population health and infection risk. In reservoir hosts, infection status and pathogen shedding are affected by processes interacting across different scales: from landscape features affecting host location and transmission to within‐host processes affec...

Understanding where and when pathogens occur in the environment has implications for reservoir population health and infection risk. In reservoir hosts, infection status and pathogen shedding are affected by processes interacting across different scales: from landscape features affecting host location and transmission to within-host processes affec...

Medically important ixodid ticks often carry multiple pathogens, with individual ticks frequently coinfected and capable of transmitting multiple infections to hosts, including humans. Acquisition of multiple zoonotic pathogens by immature blacklegged ticks (Ixodes scapularis) is facilitated when they feed on small mammals, which are the most compe...

Although human exposure to the ticks that transmit Lyme-disease bacteria is widely considered to occur around people’s homes, most studies of variation in tick abundance and infection are undertaken outside residential areas. Consequently, the patterns of variation in risk of human exposure to tick-borne infections in these human-dominated landscap...

Background Controlling populations of ticks with biological or chemical acaricides is often advocated as a means of reducing human exposure to tick-borne diseases. Reducing tick abundance is expected to decrease immediate risk of tick encounters and disrupt pathogen transmission cycles, potentially reducing future exposure risk. Materials and Meth...

Acaricides are hypothesized to reduce human risk of exposure to tick-borne pathogens by decreasing the abundance and/or infection prevalence of the ticks that serve as vectors for the pathogens. Acaricides targeted at reservoir hosts such as small mammals are expected to reduce infection prevalence in ticks by preventing their acquisition of zoonot...

Aim Amphibian populations are threatened globally by anthropogenic change and Batrachochytrium dendrobatidis (Bd), a fungal pathogen causing chytridiomycosis disease to varying degrees of severity. A closely related new fungal pathogen, Batrachochytrium salamandrivorans (Bsal), has recently left its supposed native range in Asia and decimated some...

Increasing incidence of tick-borne human diseases and geographic range expansion of tick vectors elevates the importance of research on characteristics of tick species that transmit pathogens. Despite their global distribution and role as vectors of pathogens such as Rickettsia spp., ticks in the genus Dermacentor Koch, 1844 (Acari: Ixodidae) have...

El orden Carnivora incluye más de 300 especies que varían en tamaño en muchos órdenes de magnitud y habitan en todos los biomas principales, desde las selvas tropicales hasta los mares polares. La gran diversidad de parásitos carnívoros representa una fuente de posibles enfermedades emergentes en humanos. El riesgo zoonótico de este grupo puede deb...

Aim Macroecological studies that require habitat suitability data for many species often derive this information from expert opinion. However, expert‐based information is inherently subjective and thus prone to errors. The increasing availability of GPS tracking data offers opportunities to evaluate and supplement expert‐based information with deta...

Tickborne diseases (TBDs) such as Lyme disease result in ≈500,000 diagnoses annually in the United States. Various methods can reduce the abundance of ticks at small spatial scales, but whether these methods lower incidence of TBDs is poorly understood. We conducted a randomized, replicated, fully crossed, placebo-controlled, masked experiment to t...

Back and forth transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between humans and animals will establish wild reservoirs of virus that endanger long-term efforts to control COVID-19 in people and to protect vulnerable animal populations. Better targeting surveillance and laboratory experiments to validate zoonotic poten...

Postdoctoral positions provide critical opportunities for early‐career ecologists to build transferable skills, knowledge, and networks that will prepare them for professional success. However, these positions often come with personal and professional challenges such as stress, isolation, and lack of agency. Here, we describe a peer‐led postdoc pro...

The order Carnivora includes over 300 species that vary many orders of magnitude in size and inhabit all major biomes, from tropical rainforests to polar seas. The high diversity of carnivore parasites represents a source of potential emerging diseases of humans. Zoonotic risk from this group may be driven in part by exceptionally high functional d...

Current methods for viral discovery target evolutionarily conserved proteins that accurately identify virus families but remain unable to distinguish the zoonotic potential of newly discovered viruses. Here, we apply an attention-enhanced long-short-term memory (LSTM) deep neural net classifier to a highly conserved viral protein target to predict...

The forage maturation hypothesis (FMH) states that energy intake for ungulates is maximised when forage biomass is at intermediate levels. Nevertheless, metabolic allometry and different digestive systems suggest that resource selection should vary across ungulate species. By combining GPS relocations with remotely sensed data on forage characteris...

Spillback transmission from humans to animals, and secondary spillover from animal hosts back into humans, have now been documented for SARS-CoV-2. In addition to threatening animal health, virus variants arising from novel animal hosts have the potential to undermine global COVID-19 mitigation efforts. Numerous studies have therefore investigated...

Pathogens and parasites (henceforth “pathogens”) can make up a large percentage of the biomass found in ecosystems, and therefore, their impacts on ecosystem processes should be prominent. Pathogens influence ecosystem processes by affecting the abundance or phenotype of hosts and through direct contributions to ecosystem production. However, there...

Natural ecosystems provide humans with different types of ecosystem services, often linked to biodiversity. The dilution effect (DE) predicts a negative relationship between biodiversity and risk of infectious diseases of humans, other animals, and plants. We hypothesized that a stronger DE would be observed in studies conducted at smaller spatial...

Following publication of the original article [1], one of the authors, Dr. Sarah E. Bowden reported that at the time of the study she wasn't working for the Division of Global Migration and Quarantine, Centers for Disease Control, 1600 Clifton Road, Atlanta, GA 30329-4027, USA.

Background: Exposure to blacklegged ticks Ixodes scapularis that transmit pathogens is thought to occur peri-domestically. However, the locations where people most frequently encounter infected ticks are not well characterized, leading to mixed messages from public health officials about where risk is highest. Methods: We conducted a systematic...

The emergence and spread of Lyme disease and other infections associated with blacklegged ticks is causing a public health crisis. No human vaccines are available, and both diagnosis and treatment are sometimes ineffectual, leading to advocacy for self-directed preventative measures. These recommendations are widely communicated to the public but w...

Public health authorities recommend a range of nonchemical measures to control blacklegged ticks Ixodes scapularis Say, 1821 (Ixodida: Ixodidae) in residential yards. Here we enumerate these recommendations and assess their relationship to larval tick abundance in 143 yards in Dutchess County, New York, an area with high Lyme disease incidence. We...

The blacklegged tick Ixodes scapularis is the primary vector for the bacterium causing Lyme disease in eastern North America and for other medically important pathogens. This species is vulnerable to attack by fungal pathogens and arthropod predators, but the impacts of interactions between biocontrol agents have not been examined. The biocontrol a...

Restrictions on roaming Until the past century or so, the movement of wild animals was relatively unrestricted, and their travels contributed substantially to ecological processes. As humans have increasingly altered natural habitats, natural animal movements have been restricted. Tucker et al. examined GPS locations for more than 50 species. In ge...

Previous studies have found that Met52®, which contains the entomopathogenic fungus Metarhizium brunneum, is effective in reducing the abundance of Ixodes scapularis, the tick vector for the bacterium causing Lyme disease and for other tick-borne pathogens. Given widespread interest in effective, safe methods for controlling ticks, Met52 has the po...

Analysis of deviance for the best-fitting model of arthropod abundance in bulk samples, considering data taken pre-treatment and 1 week post-treatment. There was a significant effect of habitat. (CSV)

Pitfall sample means and BACI effects. Order-level means (standard errors) and Before-After-Control-Impact effects (SEs) for pitfall samples. (CSV)

Analysis of deviance for the best-fitting model of arthropod abundance in pitfall samples, considering data taken pre-treatment and 1 week post-treatment. There was a significant effect of period. (CSV)

R code for retrospective and prospective bootstrap power analysis. (ZIP)

Analysis of deviance for the best-fitting model of arthropod abundance in bulk samples, considering data taken pre-treatment and 3 weeks post-treatment. There were significant effects of period, habitat, and location. (CSV)

Bulk sample means and BACI effects. Order-level means (standard errors) and Before-After-Control-Impact effects (SEs) for bulk samples. (CSV)

Analysis of deviance for the best-fitting model of arthropod abundance in pitfall samples, considering data taken pre-treatment and 5 weeks post-treatment. There was a significant effect of period and habitat. (CSV)

Arthropod abundance over time in bulk samples. Mean and standard error abundance for each order and sampling occasion for Met52 and control (H2O) plots for bulk sample data. (PNG)

Arthropod abundance over time in pitfall samples. Mean and standard error abundance for each order and sampling occasion for Met52 and control (H2O) plots for pitfall sample data. (PNG)

Understanding why animal societies take on the form that they do has benefited from insights gained by applying social network analysis to patterns of individual associations. Such analyses typically aggregate data over long time periods even though most selective forces that shape sociality have strong temporal elements. By explicitly incorporatin...

During my tenure as an AGU Congressional Science Fellow, which began in September 2010 and continues until November 2011, my time has been shared between working with the U.S. House of Representatives Natural Resource Committee Democratic staff and in the office of Rep. Ed Markey (D-Mass., ranking Democrat on the committee). I appreciate getting to...

Hybridization between an abundant species and an endangered species is cause for concern. When such hybridization is observed, it is both urgent and necessary to assess the level of threat posed to the endangered species. We report the first evidence of natural hybridization between two equids: the endangered Grevy's zebra Equus grevyi and the abun...

Setting wildlife conservation priorities and determining how to meet them is challenging, particularly when policy decisions made at large scales need to be informed by a diversity of local conditions. The persistence of species that range widely demands that they coexist with people both within and outside formally protected areas. It is often pol...

Researchers studying animal societies often begin by testing whether a population shows nonrandom social structure, by comparing observed social associations with the predictions of a null model. Association data comprises observations of individuals in groups, which are observed through repeated surveys. Each survey is conducted on a discrete occa...

Animal groups arise from individuals’ choices about the number, characteristics, and identity of associates. Individuals make these choices to gain benefits from their associations. As the needs of an individual change with its phenotype, so too we expect the nature of its associations to vary. In this paper, we investigate how the social prioritie...

We describe a fight between two female plains zebra (Equus burchelli). Plains zebra are ungulates with stable social groups known as harems. Female aggression rarely escalates to the level we observed. The fight immediately followed the birth of a foal to one of the females. The initiating female repeatedly kicked and bit the mother, who reacted ag...

Characterizing habitat choice is essential for endangered species conservation. For the endangered Grevy's zebra (Equus grevyi), as with many widely ranging vertebrates, human activities may be an important factor affecting space use. Grevy's zebras are grazing ungulates inhabiting the savannahs of central-northern Kenya and Ethiopia. Past research...

In traditional models for social organization, female movements and association patterns track resource distribution, whereas males track females. More recently, this model has been expanded to include feedback effects of male behavior, especially sexual harassment, on female decisions. In Grevy's zebra (Equus grevyi), males defend territories cont...

Prey species must adapt their behavior to avoid predation. As a key prey item for lions (Panthera leo), plains zebras (Equus burchelli) were expected to respond to immediate threats posed by lions in their area. In addition, zebras were predicted to exhibit behavior tuned to reduce the potential for encounters with lions, by modifying their movemen...

In animal groups, collective movements emerge from individual interactions. Biologists seek to identify how characteristics of actors in these groups, and their relationships, influence the decision-making process. We distinguished two basic factors determining leadership in group choices: identity and state. We hypothesized that identity is more i...

For species in which group membership frequently changes, it has been a challenge to characterize variation in individual interactions and social structure. Quantifying this variation is necessary to test hypotheses about ecological determinants of social patterns and to make predictions about how group dynamics affect the development of cooperativ...

Asiatic wild asses inhabit some of the most arid environments in the world. All live in fission- fusion societies, but demography varies and the deserts in which they live often differ in subtle ways. Characterizing details of social structure of wild ass populations has been a challenge and has made it difficult to determine causes and consequence...

Precautionary principles have been proposed as a fundamental element of sound risk management. Their advocates see them as guiding action in the face of uncertainty, encouraging the adoption of measures that reduce serious risks to health, safety, and the environment. Their opponents may reject the very idea of precautionary principles, find specif...

Risks can be judged unacceptable for instrumental reasons, because they appear too large, relative to the associated benefits. They can also be judged unacceptable for fundamental reasons, because it is deemed morally or ethically wrong to incur them. With novel risks, these two sets of judgments are interrelated, as individuals look at the risk an...

When the public decides that a product or production process is socially unacceptable, the share price of the firms involved may suffer. The danger is that, out of distaste, peo - ple will refrain from buying the product or the shares. But being able to assess the de - gree of unacceptability can mean being better able to assess how it will affect...

Surveys eliciting opinions about biotechnology applications suggest the following conclusions. (1) People distinguish among biotechnologies. (2) Different people have different views about biotechnologies. (3) People have limited knowledge about biotechnologies—and know it. (4) People have strong opinions about how biotechnologies are managed. (5)...

Precautionary principles have been proposed as a fundamental element of sound risk management. Their advocates see them as guiding action in the face of uncer- tainty, encouraging the adoption of measures that reduce serious risks to health, safety, and the environment. Their opponents may reject the very idea of precaution- ary principles, find sp...