Spatiobehavioral characteristics are stable for, and hence predictive of, most cases of contagious diseases. They should be acknowledged as a formal way of defining the epidemiology of new contagious diseases at the early stage, enabling health authorities to implement precision control and prevention of the disease at the first moment possible.

Plasmodium falciparum pathogenesis is complex and intimately connected to vascular physiology. This is exemplified by cerebral malaria (CM), a neurovascular complication that accounts for most of the malaria deaths worldwide. P. falciparum sequestration in the brain microvasculature is a hallmark of CM and is not replicated in animal models. Numerous aspects of the disease are challenging to fully

The protozoan parasite Toxoplasma gondii infects a wide range of intermediate hosts. The parasite produces brain cysts during the latent phase of its infection, in parallel to causing a loss of innate aversion in the rat host towards cat odors. Host behavioral change presumably reflects a parasitic manipulation to increase predation by definitive felid hosts, although evidence for increased predation

Pharmacological treatment remains essential to control fasciolosis in areas where infection is endemic. However, there are major constraints to treating food-producing animals. Of particular concern is the lack of flukicides for treating early Fasciola infections in ruminant livestock in some countries. In addition, the information provided in package leaflets, particularly regarding withdrawal periods

In the rural and tribal areas of India, poor healthcare services for malaria are posing a great challenge to malaria control and elimination. Digitisation in malaria healthcare services, including surveillance, diagnosis, and treatment, may be helpful in malaria control and, subsequently, may move towards the elimination goal of India by 2030.

Because most emerging human pathogens originate in mammals, many studies aim to identify host traits that determine the risk of sourcing zoonotic outbreaks. Studies regularly assert that 'fast-lived' mammal species exhibiting greater fecundity and shorter lifespans tend to host more zoonoses; however, the causes of this association remain poorly understood and they cover a range of immune and nonimmune

The illegal wildlife trade (IWT) is a criminal practice bringing several ecological and public health consequences, such as the spreading of zoonotic pathogens and/or the introduction of exotic species of animals into new geographical areas. Here, we discuss potential risks of IWT on the spreading and emergence of zoonotic pathogens.

Trypanosoma cruzi, the protozoan agent of Chagas' disease, displays a complex population structure made up of multiple strains showing a diverse ecoepidemiological distribution. Parasite genetic variability may be associated with disease outcome, hence stressing the need to develop methods for T. cruzi typing in vivo. Serological typing methods that exploit the presence of host antibodies raised against

The field of mosquito mating biology has experienced a considerable expansion in the past decade. Recent work has generated many key insights about specific aspects of mating behavior and physiology. Here, we synthesize these findings and classify swarming mosquito systems as polygynous. Male mating success is highly variable in swarms and evidence suggests that it is likely determined by both scramble

Genome-scale mutagenesis screens for genes essential for apicomplexan parasite survival have been completed in three species: Plasmodium falciparum, the major human malaria parasite, Plasmodium berghei, a model rodent malaria parasite, and the more distantly related Toxoplasma gondii, the causative agent of toxoplasmosis. These three species share 2606 single-copy orthologs, 1500 of which have essentiality

Blood-sucking insects are important vectors of disease, with biting Diptera (flies) alone transmitting diseases that cause an estimated 700 000 human deaths a year. Insect vectors also bite nonhuman hosts, linking them into host-biting networks. While the major vectors of prominent diseases, such as malaria, yellow fever, dengue, and Zika, are intensively studied, there has been limited focus on the

The COVID-19 pandemic has disrupted parasitology curricula worldwide, which is expected to lead to the reshaping of parasitology education. Here, we share our experiences of remote teaching and learning of veterinary parasitology and discuss opportunities offered by remote teaching during COVID-19 lockdowns, enabling the development of interactive online parasitology courses.

Efforts to eliminate schistosomiasis are hindered by incomplete efficacy of the only FDA-approved antischistosomal drug, praziquantel. By using postgenomic technologies, Wendt et al. and Wang et al. deciphered the function of several genes required for worm survival and pathogenesis, which opens the way for the development of innovative parasite-targeted therapies.

Artemisinin-based combination therapies (ACTs) have demonstrated in vitro inhibition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Artemisinins have also shown anti-inflammatory effects, including inhibition of interleukin-6 (IL-6) that plays a key role in the development of severe coronavirus disease 2019 (COVID-19). There is now sufficient evidence for the effectiveness of ACTs

In recent months, the parasitology research community has been tasked with investigation of the influence of parasite coinfection on coronavirus disease 2019 (COVID-19) outcomes. Herein, we share our approach to analyze the effect of the trematode Fasciola hepatica as a modulator of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and of COVID-19 pathology.

Recent gains in the fight against malaria are threatened by the emergence and spread of artemisinin and partner drug resistance in Plasmodium falciparum in the Greater Mekong Subregion (GMS). When artemisinins are combined with a single partner drug, all recommended artemisinin-based combination therapies have shown reduced efficacy in some countries in the GMS at some point. Novel drugs are not available

The threats posed by a range of viral and bacterial zoonotic diseases inevitably receive renewed attention in the wake of global pandemic events due to their overt and devastating impacts on human health and the economy. Parasitic zoonoses, however, many of which affect millions of people each day, are frequently ignored. In the case of fasciolosis, caused by infection with Fasciola hepatica or Fasciola

Unraveling the molecular interactions governing the first contact between parasite and host tissues is of paramount importance to the development of effective control strategies against parasites. In fasciolosis, a foodborne trematodiasis caused mainly by Fasciola hepatica, these early interactions occur between the juvenile worm and the host intestinal wall a few hours after ingestion of metacercariae

Here we tell the story of ivermectin, describing its anthelmintic and insecticidal actions and recent studies that have sought to reposition ivermectin for the treatment of other diseases that are not caused by helminth and insect parasites. The standard theory of its anthelmintic and insecticidal mode of action is that it is a selective positive allosteric modulator of glutamate-gated chloride channels

The Plasmodium falciparum protein VAR2CSA is a critical mediator of placental malaria, and VAR2CSA antibodies (IgGs) are important to protect pregnant women. Although infrequently detected outside pregnancy, VAR2CSA IgGs were reported in men and children from Colombia and Brazil and in select African populations. These findings raise questions about the specificity of VAR2CSA IgGs and the mechanisms

Antiparasitics acting on endo- or ectoparasites represent the second largest segment of the global animal health market, accounting for 23% of market share. However, relatively few novel antiparasitic agents have been introduced into the market during recent decades. One exception, and a groundbreaking 21st century success story, are the isoxazolines, whose full potential has not yet been entirely

Anthelmintic drugs are the major line of defense against parasitic nematode infections, but the arsenal is limited and resistance threatens sustained efficacy of the available drugs. Discoveries of the modes of action of these drugs and mechanisms of resistance have predominantly come from studies of a related nonparasitic nematode species, Caenorhabditis elegans, and the parasitic nematode Haemonchus

Differentiation is a central aspect of the parasite life cycle and encompasses adaptation to both host and environment. If we accept that evolution cannot anticipate an organism’s needs as it enters a new environment, how do parasite differentiation pathways arise? The transition between vertebrate and insect stage African trypanosomes is probably one of the better studied and involves a cell-cycle

The trypanosomatids Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. are flagellate eukaryotic parasites that cause serious diseases in humans and animals. These parasites have cell shapes defined by a subpellicular microtubule array and all share a number of important cellular features. One of these is the flagellar pocket, an invagination of the cell membrane around the proximal end of

From seminal publications in the early 1970s, the world learned that dendritic cells (DCs) are powerful and versatile antigen-presenting cells. It took a few years until the first studies expanded our understanding of the pivotal role of these immune ‘soldiers’ against ticks. Advances in biochemistry, molecular biology, and bioinformatics have shed light on the identification of key salivary molecules

The phenomenon of relapsing malaria has been recognised for centuries. It is caused in humans by the parasite species Plasmodium vivax and Plasmodium ovale, which can arrest growth at an early, asymptomatic stage as hypnozoites inside liver cells. These dormant parasites can remain quiescent for months or years, then reactivate causing symptomatic malaria. The dynamics of hypnozoite dormancy and reactivation

As an immune-privileged organ, the placenta can tolerate the introduction of antigens without inducing a strong inflammatory response that would lead to abortion. However, for the control of intracellular pathogens, a strong Th1 response characterized by the production of interferon-γ is needed. Thus, invasion of the placenta by intracellular parasites puts the maternal immune system in a quandary:

For visceral leishmaniasis (VL), a major vector-borne parasitic disease, an alternative sexual transmission route is well documented in dogs but evidence is lacking in humans. Here, we discuss the current knowledge and key questions to be answered as it may be an additional obstacle in ongoing VL elimination programs.

Mast cells (MCs) are skin-resident immune cells whose role in leishmaniasis has been recently explored. Researchers report varying inferences, that is, mast cells promote, eliminate, or have no role in leishmaniasis. This article discusses this heterogeneity in mast cell roles to facilitate potential therapeutic and vaccine interventions for these diseases.

Neutrophils are now recognized as major components of the response to Toxoplasma gondii by their contribution to parasite elimination by a number of mechanisms. This article focuses on recent advances in the understanding of the mechanisms of migration, cytokine release, and formation of extracellular traps by neutrophils during toxoplasmosis.

Traditionally, the protozoan parasite Toxoplasma gondii has been thought of as relevant to public health primarily within the context of congenital toxoplasmosis or postnatally acquired disease in immunocompromised patients. However, latent T. gondii infection has been increasingly associated with a wide variety of neuropsychiatric disorders and, more recently, causal frameworks for these epidemiological

Wildlife vaccination is of urgent interest to reduce disease-induced extinction and zoonotic spillover events. However, several challenges complicate its application to wildlife. For example, vaccines rarely provide perfect immunity. While some protection may seem better than none, imperfect vaccination can present epidemiological, ecological, and evolutionary challenges. While anti-infection and antitransmission

Parasitic protozoa of the phylum Apicomplexa cause a range of human and animal diseases. Their complex life cycles – often heteroxenous with sexual and asexual phases in different hosts – rely on elaborate cytoskeletal structures to enable morphogenesis and motility, organize cell division, and withstand diverse environmental forces. This review primarily focuses on studies using Toxoplasma gondii

Humans and crown catarrhines evolved with the inability to synthesize the oligosaccharide galactose-α-1,3-galactose (α-Gal). In turn, they naturally produce high quantities of the glycan-specific antibodies that can be protective against infectious agents exhibiting the same carbohydrate modification on their surface coat. The protective immunity induced by α-Gal is ensured through an antibody-mediated

At the crossroads of interacting biological, socioeconomic, behavioral, and institutional factors, vector-borne diseases are complex 'wicked problems'. In this article, we argue that citizen science can help in vector control by boosting scientific data collection, tapping into local knowledge, and building durable partnerships between scientists and communities.

Adequate sexual competitiveness of sterile males is a prerequisite for genetic control methods, including the sterile insect technique. During the past decade several semi-field and open-field trials demonstrated that irradiated male mosquitoes can be competitive.

Malaria eradication is a global priority but requires innovative strategies. Humoral immune responses attack different parasite stages, and antibody-based therapy may prevent malaria infection or transmission. Here, we discuss targets of monoclonal antibodies in mosquito sexual stages of Plasmodium.

Sleep is a phenomenon conserved across the animal kingdom, where studies on Drosophila melanogaster have revealed that sleep phenotypes and molecular underpinnings are similar to those in mammals. However, little is known about sleep in blood-feeding arthropods, which have a critical role in public health as disease vectors. Specifically, sleep studies in mosquitoes are lacking despite considerable

Plasmodium falciparum infections in low-transmission settings are often asymptomatic with low parasite densities despite low herd immunity. Based on studies in Zanzibar, this may be due to parasitic (nonvirulence) rather than host (immunity) factors. In high-transmission settings, high replication rate and virulence represents a competitive advantage, whereas in low-transmission settings nonvirulent

Malaria interventions may reduce the burden of clinical malaria disease, the transmission of malaria parasites, or both. As malaria interventions are developed and evaluated, including those interventions primarily targeted at reducing disease, they may also impact parasite transmission. Achieving global malaria eradication will require optimizing the transmission-reducing potential of all available

Research on Plasmodium parasites has driven breakthroughs in reducing malaria morbidity and mortality. Experimental analysis of in vivo/ex vivo versus in vitro samples serve unique roles in Plasmodium research. However, these distinctly different environments lead to discordant biology between parasites in host circulation and those under laboratory cultivation. Here, we review how in vitro factors

The last malaria parasite standing will display effective adaptations to selective forces. While substantial progress has been made in reducing malaria mortality, eradication will require elimination of all Plasmodium parasites, including those in asymptomatic infections. These typically chronic, low-density infections are difficult to detect, yet can persist for months. We argue that asymptomatic

Plasmodium parasites contain various virulence factors that modulate the host immune response. Malarial pigment, or hemozoin (Hz), is an undegradable crystalline product of the hemoglobin degradation pathway in the parasite and possesses immunomodulatory properties. An association has been found between Hz accumulation and severe malaria, suggesting that the effects of Hz on the host immune response

The unicellular trypanosomatids belong to the phylum Euglenozoa and all known species are obligate parasites. Distinct lineages infect plants, invertebrates, and vertebrates, including humans. Genome data for marine diplonemids, together with freshwater euglenids and free-living kinetoplastids, the closest known nonparasitic relatives to trypanosomatids, recently became available. Robust phylogenetic

The protozoan parasite Entamoeba histolytica is the causative agent of amebiasis, an infection that manifests as colitis and, in some cases, liver abscess. A better understanding of host protective factors is key to developing an effective remedy. Recently, significant advances have been made in understanding the mechanisms of MUC2 production by goblet cells upon amebic infection, regulation of antimicrobial

Neglected tropical diseases annually account for several million infections worldwide. Efficacious treatment for these poorly understood infectious diseases is often limited to ineffective, expensive, and toxic therapies such as the SbV used for leishmaniasis patients. Here, we review the latest discoveries and literature on the molecular pathways, cell types, and immune mediators involved in the immune

Giardia duodenalis is a major gastrointestinal parasite of humans and animals across the globe. It is also of interest from an evolutionary perspective as it possesses many features that are unique among the eukaryotes, including its distinctive binucleate cell structure. While genomic analysis of a small number of isolates has provided valuable insights, efforts to understand the epidemiology of the

Toxoplasmosis represents one of the most common comorbidity factors in solid organ or hematopoietic stem cell transplant recipients as well as in other immunocompromised patients. In the past decades, availability and performance of molecular tools for the diagnosis or the exclusion of toxoplasmosis in these patients have greatly improved. However, if accurately used, serology remains a complementary

Protein phosphatase type 1 (PP1) forms a wide range of Ser/Thr-specific phosphatase holoenzymes which contain one catalytic subunit (PP1c), present in all eukaryotic cells, associated with variable subunits known as regulatory proteins. It has recently been shown that regulators take a leading role in the organization and the control of PP1 functions. Many studies have addressed the role of these regulators

Ascariasis is a globally spread intestinal nematode infection of humans and a considerable concern in pig husbandry. Ascaris accomplishes a complex body migration from the intestine via the liver and lung before returning to the intestine. Tissue migration and the habitat shared with a complex microbial community pose the question of how the nematode interacts with microbes and host cells from various

This article summarizes discussions at a Gender Equity Workshop run during the Molecular Approaches to Malaria Conference in February 2020. Barriers to career progression in science for women and minority groups, along with suggestions to overcome ongoing roadblocks, are discussed. The emerging challenges that coronavirus disease 2019 (COVID-19) is bringing to this sector are also considered.

Among many Plasmodium proteins involved in the erythrocytic cycle, some exposed on the erythrocyte surface drive antigenic variability. Recently, Harrison et al. elucidated the structural basis by which RIFINs activate LILRB1 and suppress immune cell function. This breakthrough points to an additional strategy for survival in the human host.

Humans are protected from most African trypanosomes via high-density lipoproteins, known as trypanosome lytic factor (TLF). In humans, IgM antibodies are found associated with TLF. The recent work by Verdi et al. studied the origin of these antibodies and their binding partners, suggesting a new model for TLF uptake.

Metabolism influences biochemical networks, and arthropod vectors are endowed with an immune system that affects microbial acquisition, persistence, and transmission to humans and other animals. Here, we aim to persuade the scientific community to expand their interests in immunometabolism beyond mammalian hosts and towards arthropod vectors. Immunometabolism investigates the interplay of metabolism

Symbiosis with intracellular or gut bacteria is essential for the nutrition of animals with an obligate blood-feeding habit. Divergent bacterial lineages have independently evolved functional interactions with obligate blood feeders, but all converge to an analogous biochemical feature: the provisioning of B vitamins. Although symbionts and blood feeders coevolved interdependently for millions of years

The presentation of cysticercosis is very heterogeneous both between and within countries. Several host and parasite factors are involved in this heterogeneity. Differences in the intensity of infection pressure have not been studied thus far. We have compiled data that could demonstrate that differences in infection pressure are involved in the still high prevalence of parenchymal neurocysticercosis

Recent breakthroughs in high-throughput technologies, transcriptomics, and advances in our understanding of gene regulatory networks have enhanced our perspective on the complex interplay between parasite and host. Noncoding RNA molecules have been implicated in critical roles covering a broad range of biological processes in the Apicomplexa. Processes that are affected range from parasite development

The first experimental crosses carried out with the human malaria parasite Plasmodium falciparum played a key role in determining the genetic loci responsible for drug resistance, virulence, invasion, growth rate, and transmission. These crosses relied on splenectomized chimpanzees to complete the liver stage of the parasite's life cycle and the subsequent transition to asexual blood stage culture