Parasitic diseases: opportunities and challenges in the 21st century

The opportunities and challenges for the study and control of parasitic diseases in the 21st century are both exciting and daunting. Based on the contributions from this field over the last part of the 20th century, we should expect new biologic concepts will continue to come from this discipline to enrich the general area of biomedical research. The general nature of such a broad category of infections is difficult to distill, but they often depend on well-orchestrated, complex life cycles and they often involve chronic, relatively well-balanced host/parasite relationships. Such characteristics force biological systems to their limits, and this may be why studies of these diseases have made fundamental contributions to molecular biology, cell biology and immunology. However, if these findings are to continue apace, parasitologists must capitalize on the new findings being generated though genomics, bioinformatics, proteomics, and genetic manipulations of both host and parasite. Furthermore, they must do so based on sound biological insights and the use of hypothesis-driven studies of these complex systems. A major challenge over the next century will be to capitalize on these new findings and translate them into successful, sustainable strategies for control, elimination and eradication of the parasitic diseases that pose major public health threats to the physical and cognitive development and health of so many people worldwide.

Parasite systematics in the 21st century: opportunities and obstacles

Thanks to the phylogenetic systematics revolution, systematic parasitology is poised to make significant contributions in tropical medicine and public health, biodiversity science, and evolutionary biology. At the same time, the taxonomic impediment is acute within parasitology. Both systematists and non-systematists must be interested in working towards common goals and establishing collaborative efforts in order to re-vitalize and re-populate systematic parasitology.

The girl from the Church of the Sacrament: a case of congenital syphilis in XVIII century Lisbon

Syphilis is a sexually or congenitally transmitted infectious disease with an impact on the health of human populations that has undergone important cycles in different countries and periods of history. Its presence was first diagnosed in Europe in the late XIV century. In Portugal, although there are various written records of the infection in the last centuries, there are rare references to it in archeological findings (mummified bodies are also rare in Portugal). The current study describes a probable case of congenital syphilis in an 18-month-old girl buried in the Church of the Sacrament in Lisbon. Her body, dating to the XVIII century, was found mummified together with dozens of others, still not studied. Symmetrical periostitis of the long bones, osteitis, metaphyseal lesions, left knee articular, and epiphyseal destruction, and a rarefied lesion with a radiological appearance compatible with Wimberger's sign all point to a diagnosis of congenital syphilis. The diagnosis of this severe form of the infection, possibly related to the cause of death in this upper-class girl, calls attention to the disease's presence in XVIII century Lisbon and is consistent with the intense mobilization at the time in relation to the risks posed by so-called heredosyphilis. It is the first case of congenital syphilis in a child reported in archeological findings in Portugal, and can be correlated with other cases in skeletons of adults buried in cemeteries in Lisbon (in the XVI to XVIII centuries) and Coimbra (XIX century). Finally, this finding highlights the need to study the entire series of mummified bodies in the Church of the Sacrament in order to compare the paleopathological findings and existing historical documents on syphilis, so as to expand the paleoepidemiological knowledge of this infection in XVIII century Lisbon.

Access to diagnosis and treatment of Chagas disease/infection in endemic and non-endemic countries in the XXI century

In this article, Médicos Sin Fronteras (MSF) Spain faces the challenge of selecting, piecing together, and conveying in the clearest possible way, the main lessons learnt over the course of the last seven years in the world of medical care for Chagas disease. More than two thousand children under the age of 14 have been treated; the majority of whom come from rural Latin American areas with difficult access. It is based on these lessons learnt, through mistakes and successes, that MSF advocates that medical care for patients with Chagas disease be a reality, in a manner which is inclusive (not exclusive), integrated (with medical, psychological, social, and educational components), and in which the patient is actively followed. This must be a multi-disease approach with permanent quality controls in place based on primary health care (PHC). Rapid diagnostic tests and new medications should be available, as well as therapeutic plans and patient management (including side effects) with standardised flows for medical care for patients within PHC in relation to secondary and tertiary level, inclusive of epidemiological surveillance systems.

Diptera Brachycera found inside the esophagus of a mummified adult male from the early XIX century, Lisbon, Portugal

Fly puparia and adult fragments of diptera muscid were found inside the esophagus of a mummified body from the early XIX century, buried inside the crypt of the Sacrament Church (Lisbon, Portugal). The identification of the material revealed a monospecific colonization by Ophyra capensis (Wiedemann) (Diptera: Muscidae), a species known to invade corpses in the ammoniacal fermentation wave. This species can be found in corpses kept indoors, not available to the early waves of blowflies (Diptera: Calliphoridae). In the present case, the number of pupae and their developmental stage suggest that the female invaded the mummified corpse through the partially opened mouth and the oviposition took place directly inside the esophagus. This is the first case of O. capensis infesting internal organs of an intact corpse. The use of chemical products for the embalming process probably explains why external colonization did not occur.

RFLP clusters of Mycobacterium tuberculosis strains from the Indian Ocean Region: local and South Asian characteristics

This is the first study describing the genetic polymorphism of Mycobacterium tuberculosis strains in the Indian Ocean Region. Using IS6110 RFLP analysis, 475 M. tuberculosis isolates from Madagascar, Comoros, Mauritius, Mozambique and La Reunion were compared. Of the 332 IS6110 profiles found, 43 were shared by clusters containing 2-65 strains. Six clusters were common to at least two countries. Of 52 families of strains with similar IS6110 profiles, 10 were common to at least two countries. Interestingly, another characteristic was the frequency (16.8%) of IS6110 single-copy strains. These strains could be distinguished using the DR marker. This preliminary evaluation suggests genetic similarity between the strains of the Indian Ocean Region. However, additional markers would be useful for epidemiological studies and to assess the ancient transmission of strains between countries of this region.

A century of research: what have we learned about the interaction of Trypanosoma cruzi with host cells?

Since the discovery of Trypanosoma cruzi and the brilliant description of the then-referred to "new tripanosomiasis" by Carlos Chagas 100 years ago, a great deal of scientific effort and curiosity has been devoted to understanding how this parasite invades and colonises mammalian host cells. This is a key step in the survival of the parasite within the vertebrate host, and although much has been learned over this century, differences in strains or isolates used by different laboratories may have led to conclusions that are not as universal as originally interpreted. Molecular genotyping of the CL-Brener clone confirmed a genetic heterogeneity in the parasite that had been detected previously by other techniques, including zymodeme or schizodeme (kDNA) analysis. T. cruzi can be grouped into at least two major phylogenetic lineages: T. cruzi I, mostly associated with the sylvatic cycle and T. cruzi II, linked to human disease; however, a third lineage, T. cruziIII, has also been proposed. Hybrid isolates, such as the CL-Brener clone, which was chosen for sequencing the genome of the parasite (Elias et al. 2005, El Sayed et al. 2005a), have also been identified. The parasite must be able to invade cells in the mammalian host, and many studies have implicated the flagellated trypomastigotes as the main actor in this process. Several surface components of parasites and some of the host cell receptors with which they interact have been described. Herein, we have attempted to identify milestones in the history of understanding T. cruzi- host cell interactions. Different infective forms of T. cruzi have displayed unexpected requirements for the parasite to attach to the host cell, enter it, and translocate between the parasitophorous vacuole to its final cytoplasmic destination. It is noteworthy that some of the mechanisms originally proposed to be broad in function turned out not to be universal, and multiple interactions involving different repertoires of molecules seem to act in concert to give rise to a rather complex interplay of signalling cascades involving both parasite and cellular components.

All-around care for patients with Chagas disease: a challenge for the XXI century

In 1987, the University of Pernambuco's Oswaldo Cruz Hospital in Recife, Brazil opened its Chagas Disease and Heart Failure Outpatient Clinic with the aim of providing its patients all-around care through adoption of a biopsychosocial model of care. All-around care involves caring for the patient as a whole human being in the context of the biological, psychological and social factors present, which are an inherent part of the human condition. One prerequisite for the proposed model of care is the participation of a multidisciplinary team of trained technical staff committed to this framework. Although the main focus of the service is on care, teaching and research are also an important part of its work. The Pernambuco Association of Chagas Disease Patients is guided by the same model of care and has been carrying out educational activities relating to the disease, its treatment and support for patients and family members for several years. This Association plays an important role in advocating to public authorities on behalf of patients. The accumulated experience of the past 22 years has shown us that a broad vision of health care can help clinicians and policy makers to make decisions that are more in tune with the everyday reality of the patient, which in turn has a positive impact on adherence to treatment and quality of life.

Paleoparasitological report on Ascaris aDNA from an ancient East Asian sample

In this study, Ascaris DNA was extracted and sequenced from a medieval archaeological sample in Korea. While Ascaris eggs were confirmed to be of human origin by archaeological evidence, it was not possible to pinpoint the exact species due to close genetic relationships among them. Despite this shortcoming, this is the first Ascaris ancient DNA (aDNA) report from a medieval Asian country and thus will expand the scope of Ascaris aDNA research.

Syphilis and cirrhosis: a lethal combination in a XIX century individual identified from the Medical Schools Collection at the University of Coimbra (Portugal)

Syphilis is a chronic infection that is categorized by a three-stage progression. The tertiary stage may affect bones and produce distinctive skull lesions called caries sicca. This paper aims to present an unusual case of syphilis associated with a diagnosis of cirrhosis, which was recorded as the cause of death in a 28-year-old female in 1899. The appearance and distribution of the lesions were compatible with acquired syphilis, as observed in the skull from the Medical Schools Collection of the University of Coimbra. However, the cause of death was recorded as "hypertrophic cirrhosis of the liver", this is a condition that is compatible with several liver disorders, including a primary liver disorder, such as cirrhosis provoked by alcoholism, infection of the liver by syphilis pathogens or by damage to the liver from the use of mercury compounds, which was the common treatment for syphilis at the time. This paper represents a contribution to the understanding of the natural evolution of syphilis.

Paleoparasitologic, paleogenetic and paleobotanic analysis of XVIII century coprolites from the church La Concepción in Santa Cruz de Tenerife, Canary Islands, Spain

We present the results of a paleoparasitologic, paleogenetic and paleobotanic analysis of coprolites recovered during the excavation of the church La Concepción in Santa Cruz de Tenerife. Coprolites (n = 4) were rehydrated and a multidisciplinary analysis was conducted. The paleobotanic analysis showed numerous silicates, seeds and fruits of the family Moraceae. In the paleoparasitologic study, Ascaris sp. eggs (n = 344) were identified. The paleogenetic results confirmed the Ascaris sp. infection as well as the European origin of human remains. These findings contribute to our knowledge of ancient helminthes infections and are the first paleoparasitological record of Ascaris sp. infection in Spain.

The dynamics of Brazilian protozoology over the past century

Brazilian scientists have been contributing to the protozoology field for more than 100 years with important discoveries of new species such asTrypanosoma cruzi and Leishmania spp. In this work, we used a Brazilian thesis database (Coordination for the Improvement of Higher Education Personnel) covering the period from 1987-2011 to identify researchers who contributed substantially to protozoology. We selected 248 advisors by filtering to obtain researchers who supervised at least 10 theses. Based on a computational analysis of the thesis databases, we found students who were supervised by these scientists. A computational procedure was developed to determine the advisors’ scientific ancestors using the Lattes Platform. These analyses provided a list of 1,997 researchers who were inspected through Lattes CV examination and allowed the identification of the pioneers of Brazilian protozoology. Moreover, we investigated the areas in which researchers who earned PhDs in protozoology are now working. We found that 68.4% of them are still in protozoology, while 16.7% have migrated to other fields. We observed that support for protozoology by national or international agencies is clearly correlated with the increase of scientists in the field. Finally, we described the academic genealogy of Brazilian protozoology by formalising the “forest” of Brazilian scientists involved in the study of protozoa and their vectors over the past century.

Essays on the history of Brazilian dipterology. I. The first notices about Brazilian Diptera (16th century)

Essays on the history of Brazilian dipterology. I. The first notices about Brazilian Diptera (16th century). This paper presents a historical resume of the first notices about Brazilian Diptera during the 16th century, given by Francisco Pires in 1552 (the oldest mention known), José de Anchieta, Leonardo do Valle, Pero de Magalhães de Gandavo, Jean de Léry and Gabriel Soares de Souza, ending with Fernão Cardim, who made the last mentions of Brazilian Diptera in that century.

Essays on the history of Brazilian dipterology: II. notices about Brazilian Diptera (17th century)

Essays on the history of Brazilian dipterology. II. Notices about Brazilian Diptera (17th century). Notices from the Brazilian Diptera from the 17th century come mainly from two foreign invasions occurred in Brazil, the first one by the French in Maranhão and the second by the Dutch in northeastern Brazil. This paper includes reports of Fathers Claude d'Abbeville and Yves d'Evreux and from Piso and Marcgrave, the last two presenting the first illustrations of Brazilian Diptera. The paper also includes reports of Friar Laureano de la Cruz, Father João de Sotto Mayor and Maurício de Heriarte.

Essays on the history of brazilian dipterology: III. Three remarkable notices from the 18th century, mainly related to myiasis-producing flies (Cochliomyia and Dermatobia)

This paper registers reports about dipterans made by three Portuguese who lived in Brazil during the 18th century. Luiz Gomes Ferreira, in his book "Erário mineral" ["Mineral revenue"], wrote curious passages related with myiasis-causing flies of the genus Cochliomyia. José Rodrigues de Mello registered, in Latin verses, the folklore for curing myiases caused by Cochliomyia hominivorax in cattle. Luiz dos Santos Vilhena, in the last of his twenty letters dealing with several aspects of life in Brazil, made reference to horseflies, human bot flies and mosquitos.