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Biogeographic range expansion into South America by Coccidioides immitis mirrors New World patterns of human migration.

Long-distance population dispersal leaves its characteristic signature in genomes, namely, reduced diversity and increased linkage between genetic markers. This signature enables historical patterns of range expansion to be traced. Herein, we use microsatellite loci from the human pathogen Coccidioides immitis to show that genetic diversity in this fungus is geographically partitioned throughout North America. In contrast, analyses of South American C. immitis show that this population is genetically depauperate and was founded from a single North American population centered in Texas. Variances of allele distributions show that South American C. immitis have undergone rapid population growth, consistent with an epidemic increase in postcolonization population size. Herein, we estimate the introduction into South America to have occurred within the last 9,000-140,000 years. This range increase parallels that of Homo sapiens. Because of known associations between Amerindians and this fungus, we suggest that the colonization of South America by C. immitis represents a relatively recent and rapid codispersal of a host and its pathogen.

Base Sequence↗

Invasions by Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in the Western Hemisphere: implications for South America.

The multicolored Asian lady beetle, Harmonia axyridis (Pallas), native to Asia, has recently been detected in South America after successfully invading North America and Europe. This coccinellid is a voracious predator; therefore, it is popular and effective in biological control. Unfortunately, H. axyridis also has associated adverse impacts (i.e., as a household pest, pest of fruit production, and threat to non-target organisms). To predict the potential geographic extent of impacts of H. axyridis in South America we review the history of its invasion in the Western Hemisphere and address various factors critical to the future invasion (i.e., arrival, establishment, and spread) of new areas of South America. The likelihood of continued introductions (i.e., arrival) of H. axyridis to South America seems high, due to its popularity as a biological control agent and through accidental introductions. Establishment also seems likely in broad regions of South America. Climate matching with the native range suggested that much of southern South America may be suitable for establishment. In contrast, habitat matching with the native range suggested that northern South America may be more suitable. In addition, prey availability should not limit establishment of this predator. Once established, H. axyridis seems likely to spread by flight and human-assisted means. Overall, the invasion of H. axyridis over broad areas in South America seems likely.

Animal Migration↗

Arrival and diversification of caviomorph rodents and platyrrhine primates in South America.

Platyrrhine primates and caviomorph rodents are clades of mammals that colonized South America during its period of isolation from the other continents, between 100 and 3 million years ago (Mya). Until now, no molecular study investigated the timing of the South American colonization by these two lineages with the same molecular data set. Using sequences from three nuclear genes (ADRA2B, vWF, and IRBP, both separate and combined) from 60 species, and eight fossil calibration constraints, we estimated the times of origin and diversification of platyrrhines and caviomorphs via a Bayesian relaxed molecular clock approach. To account for the possible effect of an accelerated rate of evolution of the IRBP gene along the branch leading to the anthropoids, we performed the datings with and without IRBP (3768 sites and 2469 sites, respectively). The time window for the colonization of South America by primates and by rodents is demarcated by the dates of origin (upper bound) and radiation (lower bound) of platyrrhines and caviomorphs. According to this approach, platyrrhine primates colonized South America between 37.0 +/- 3.0 Mya (or 38.9 +/- 4.0 Mya without IRBP) and 16.8 +/- 2.3 (or 20.1 +/- 3.3) Mya, and caviomorph rodents between 45.4 +/- 4.1 (or 43.7 +/- 4.8) Mya and 36.7 +/- 3.7 (or 35.8 +/- 4.3) Mya. Considering both the fossil record and these molecular datings, the favored scenarios are a trans-Atlantic migration of primates from Africa at the end of the Eocene or beginning of the Oligocene, and a colonization of South America by rodents during the Middle or Late Eocene. Based on our nuclear DNA data, we cannot rule out the possibility of a concomitant arrival of primates and rodents in South America. The caviomorphs radiated soon after their arrival, before the Oligocene glaciations, and these early caviomorph lineages persisted until the present. By contrast, few platyrrhine fossils are known in the Oligocene, and the present-day taxa are the result of a quite recent, Early Miocene diversification.

Animal Migration↗

The realistic possibilities of chemotherapy for pulmonary tuberculosis in South America.

The slow integration of antituberculosis programmes into general health service activities is the most important problem encountered. Short course regimes with high cost drugs require the supervision which, for the time being, is difficult to realize on a large scale except, perhaps, in big cities. Though pilot studies of short course regimes are welcomed, for the immediate use in both the capitals and the rural areas mainly self-administered low-cost systems may be considered for the chemotherapy of tuberculosis, with basic division of patients into groups of previously untreated and previously treated persons (which would affect the drug combination used), and smear (and culture?) positive or negative persons (which might affect the duration of therapy administered). For the latter, it is of considerable importance to continue improving the network of bacteriological laboratories.

Antitubercular Agents↗

Epidemiology of quinolone resistance: Europe and North and South America.

After nearly 10 years of fluoroquinolone usage for a wide range of bacterial infections, a striking difference has been observed in the incidence of bacterial resistance to fluoroquinolones between bacteria responsible for community- and hospital-acquired infections, respectively. Resistance is only rarely encountered among common pathogens. In most studies, 97 to 100% of all pathogens are fully susceptible to fluoroquinolones. In contrast, resistance to fluoroquinolones has emerged and increased among bacteria responsible for nosocomial infections. The incidence of resistance to fluoroquinolones varies between bacterial species, clinical settings and countries, and is related to local epidemic spread of a few clones. The highest incidence of resistance is observed in Pseudomonas aeruginosa, Acinetobacter spp., Serratia marcescens and, particularly, methicillin-resistant Staphylococcus aureus (MRSA): some investigators have reported 95 to 100% fluoroquinolone resistance among MRSA. Follow-up of trends in the resistance to fluoroquinolones based upon surveillance programmes are needed.

4-Quinolones↗

Reports and recommendations on the teaching of and training in gastroenterology in South America.

This report is based on information obtained from the medical education associations of Brazil, Colombia, and Chile. It seems that a similar policy is followed by the other countries of Latin America. The aim of the undergraduate teaching is the training of a general physician. The teaching of subspecialities is just a part of internal medicine. The education and training program should take this interrelationship into account, to prepare a general physician concerned with the biopsychosocial unity of the patient. The students must be trained for the diagnosis and management of the commonest disorders of the alimentary tract. As a speciality, gastroenterology education starts after graduation, in a 2-year program of medical residency, following a 1-year training in internal medicine. In Brazil there are courses for graduates following the medical residency program, to prepare for master's and doctor's degrees.

Education, Medical↗

Full-length genome analysis of natural isolates of vesicular stomatitis virus (Indiana 1 serotype) from North, Central and South America.

Most studies on the molecular biology and functional analysis of vesicular stomatitis virus Indiana 1 serotype (VSV-IN1) are based on the only full-length genomic sequence currently deposited in GenBank. This sequence is a composite of several VSV-IN1 laboratory strains passaged extensively in tissue culture over the years and it is not certain that this sequence is representative of strains circulating in nature. We describe here the complete genomic sequence of three natural isolates, each representing a distinct genetic lineage and geographical origin: 98COE (North America), 94GUB (Central America) and 85CLB (South America). Genome structure and organization were conserved, with a 47 nucleotide 3' leader, five viral genes -- N, P, M, G and L -- and a 59 nucleotide 5' trailer. The most conserved gene was N, followed by M, L and G, with the most variable being P. Sequences containing the polyadenylation and transcription stop and start signals were completely conserved among all the viruses studied, but changes were found in the non-transcribed intergenic nucleotides, including the presence of a trinucleotide at the M-G junction of the South American lineage isolate. A 102-189 nucleotide insertion was present in the 5' non-coding region of the G gene only in the viruses within a genetic lineage from northern Central America. These full-length genomic sequences should be useful in designing diagnostic probes and in the interpretation of functional genomic analyses using reverse genetics.

Base Sequence↗

[Psychiatric care policies and deinstitutionalization in South America].

INTRODUCTION: The process of restructuring psychiatric care in South America began in the 80's and increased in the 90's. This process had its landmark in the Declaration of Caracas (1990), which reinforced the need for alternative services to the mental hospital. OBJECTIVES: to analyse the current situation of the psychiatric care in South America, with special emphasis on Psychiatric Units in General Hospitals (PUGHs). METHODS: Two mail surveys were carried out. Questionnaires were sent to all Ministries of Health, Psychiatric Societies and key informants. RESULTS: All countries were represented in the returned questionnaires. In 7 countries there is a mental health plan. Material and human resources are inadequate in most countries. There has been a decrease in the total number of psychiatric beds over the last tem years. PUGHs were created in all the countries surveyed. CONCLUSIONS: All South America countries have a mental health program. A higher percentage of the programs is devoid of an evaluation system and almost all the countries lack budget estimates for mental health care. It was observed that the total number of psychiatric beds has been decreasing in most countries, and that the PUGHs and other decentralized centers were adopted as an alternative to the mental hospital.

Deinstitutionalization↗

[Human ecological and epidemiological studies of Japanese immigrants and their descendants in South America].

Over a million people of Japanese origin reside in South America. However, only a limited number of studies on their health status and lifestyle factors affecting it have been carried out. The author and his co-workers have been conducting a series of field surveys on the health situation and lifestyle factors in Japanese immigrants and their descendants in various areas of South America. The subjects of the first-phase study were residents in four agricultural settlements (colonies) in the suburbs of Brazil, Paraguay and Bolivia. The levels of minerals and heavy metals in the hair were measured, and significant variations were found in several elements. These different levels were found to be regulated by the environmental level of their living place and by the dietary pattern. In the second-phase study, several health-related indicators such as blood pressure, anthropometric features, viral infection markers in sera, and dietary pattern were investigated in two group of immigrants, one from Okinawa and the other from the mainland of Japan, both living in Bolivia. Differences in health situation and lifestyle were identified between them. Traditional habits seen in their original places of residence in Japan still existed in their life in Bolivia, while the introduction of Bolivian lifestyle was prevalent among them. Although the number of Japanese residents in Brazil is largest in the world outside of Japan, little has been known about their health situation. The subjects of the third-phase study were Japanese Brazilians. A descriptive epidemiologic study was carried out, and the mortality and incidence of cancer were determined. Some changes in disease pattern were noted when compared with Japanese in Japan, but these changes were not as marked as in the case of Japanese in the U.S.. A cross-section study on the lifestyle factors of Japanese residents in São Paulo showed some differences in health-related indicators and dietary habits in comparison with Japanese living in five areas of Japan. Such differences were also found among Japanese in São Paulo according to the place of origin in Japan. These series of studies in Japanese immigrants in South America showed the importance of lifestyle factors, especially dietary habits, for the health situation.

Blood Pressure↗

Transboundary Conservation: An Ecoregional Approach to Protect Neotropical Migratory Birds in South America

/ Future conservation efforts will need to transcend geopolitical boundaries in efforts to protect entire landscapes and ecosystems. Neotropical migratory birds are as a group a useful conservation tool for linking diverse landscapes and people due to their dependence on multiple habitats, sensitivity to habitat changes, and universal public appeal. The conservation of neotropical migrants can therefore function as a powerful hemispheric umbrella for ecosystem protection. Efforts to protect neotropical migratory birds on their nonbreeding grounds have traditionally been focused on Mexico, Central America, and the Caribbean. To assess the importance of South America to neotropical migrants, an ecoregional classification system was used to determine species distributions in the Andean/Southern Cone Region (Bolivia, Colombia, Ecuador, Paraguay, Peru, and Venezuela). The occurrence of migrants in protected areas that are part of The Nature Conservancy's Parks in Peril program was also assessed. Of the 406 neotropical migrant species, nearly one third (132) occur as regular nonbreeding residents in the region and for almost half of these species (53), South America is their main nonbreeding ground. All Parks in Peril sites were found to harbor neotropical migrants. Forty-eight species (36%) have declining long-term North American Breeding Bird Survey population trends and/or high Partners in Flight concern scores and thus are of significant conservation concern. Most importantly, 29 species (22%) of conservation concern use South America as their primary nonbreeding ground, indicating a need for focused conservation action. The nature of the ecoregional approach used in this endeavor makes future prioritization of ecoregions and conservation strategies for neotropical migrants across national boundaries possible. The ability to link diverse landscapes using a common element such as migratory birds allows for unique transboundary partnerships and opportunities for habitat conservation, which support the goal of the Conservancy's new Migratory Bird Initiative.KEY WORDS: Neotropical migratory birds; Transboundary conservation; Ecoregions; Protected areas; South America

Journal Article↗

Molecular population genetics of the malaria vector Anopheles darlingi in Central and South America.

To analyze the genetic relatedness and phylogeographic structure of Anopheles darlingi from 19 localities throughout Central and South America, we used a minimum spanning network, diversity measures, differentiation, neutrality tests, and mismatch distribution with mitochondrial cytochrome oxidase subunit I (COI) sequences. All the Central American haplotypes were separated by seven mutational steps from the South American haplotypes and the FST distance-based neighbor-joining tree showed a primary division between Central and South America, evidence for a putative gene pool division. More ancestral and diverse haplotypes were found in Amazonian and southern Brazil populations, suggesting that Central American populations may have originated in South America. The patterns of the mtDNA haplotype diversity and five of six tests for equilibrium implicate demographic expansion in the South American populations as the historical structure, but mismatch distribution depicts populations at mutation drift equilibrium (MDE). In South America, the departure from equilibrium was consistent with an expansion that occurred during the Pleistocene.

Animals↗

Ticks (Ixodidae) on humans in South America.

Twenty eight species of Ixodidae have been found on man in South America (21 Amblyomma, 1 Boophilus, 2 Dermacentor, 2 Haemaphysalis, 1 Ixodes and 1 Rhipicephalus species). Most of them are rarely found on man. However, three species frequently parasitize humans in restricted areas of Argentina (A. neumanni reported from 46 localities), Uruguay (A. triste from 21 sites) and Argentina-Brazil (A. parvum from 27 localities). The most widespread ticks are A. cajennense (134 localities in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, Suriname and Venezuela), A. ovale (37 localities in Argentina, Brazil, Ecuador, French Guiana, Guyana, Paraguay, Suriname and Venezuela) and A. oblongoguttatum (28 sites in Brazil, Colombia, French Guiana, Guyana, Suriname and Venezuela). Amblyomma aureolatum (18 localities in Argentina, Brazil, French Guiana and Paraguay), A. cajennense, and A. triste are vectors of rickettsioses to man in South America. A better understanding of the respective roles of these and other tick species in transmitting pathogens to humans will require further local investigations. Amblyomma ticks should be the main subjects of these studies followed by species of Boophilus, Dermacentor, Haemaphysalis and Rhipicephalus species. In contrast with North America, Europe and Asia, ticks of the genus Ixodes do not appear to be major players in transmitting diseases to human. Indeed, there is only one record of an Ixodes collected while feeding on man for all South America.

Animals↗

Epidemiology and clinical characteristics of classic Kaposi's sarcoma, seroprevalence, and variants of human herpesvirus 8 in South America: a critical review of an old disease.

OBJECTIVE: To review the current South American literature on classic Kaposi's sarcoma (KS) and human herpesvirus 8 (HHV-8), and point the way for studies that still need to be performed. MATERIALS AND METHODS: The authors performed an exhaustive search in LILACS, SCIELO and PUBMED databases for classic KS and HHV-8 in South America. The relevant material was evaluated and reviewed. RESULTS: More than 250 cases have been reported with three big case series (Argentina, Colombia and Peru). The classic KS form seen in Colombia resembles the type of disease seen among African communities; the same unusual presentation with confluent exophytic nodules or eroded lesions has been noticed in Peru. Low rates of HHV-8 antibodies have been found in blood donors from Chile, Argentina and Brazil (3%, 4%, 2.8-7.4%, respectively); whereas high rates of HHV-8 antibodies have been found in Amerindians from Brazil and Ecuador. Five specimens from Argentina were subtyped: (three classic KS and two AIDS KS); the identified strains fell into subtypes A and C. AIDS-related KS specimens from Brazil and Venezuela were subtyped: (43 and nine respectively); analysis grouped them predominantly into subgroups A, B and C. A new HHV-8 subtype E was found endemic in Brazilian and Ecuadorian Amerindians. In French Guiana ten endemic KS and six AIDS-related KS specimens were subtyped; analysis grouped them predominantly into subgroups A, B and C. CONCLUSION: Classic KS in South America has a very similar clinical presentation but not the same as the classic KS variety described in the Mediterranean. Initial seroprevalence studies performed in the general population and in blood donors showed low seroprevalence of HHV-8, whereas high seroprevalence rates were seen in Amerindian population. The existing serological assays, nonetheless, need to be further refined, and new assays need to be developed. Finally, the key to understanding the precise molecular epidemiology and phylogenetic distribution of HHV-8 in South America would be to perform more subtyping of classic KS cases.

AIDS-Related Opportunistic Infections↗

[Prevention of and attention to emergencies in South America].

The authors review the policies designed to prevent and deal with animal health emergencies which have been implemented in countries of South America. They describe the evolution of the epidemiological situation of the continent, the new arrangements for international trade in animals and products of animal origin arising from the creation of the World Trade Organization (WTO), and the consequences of such developments for livestock production in South America. Veterinary systems used to prevent and deal with emergencies in the eleven OIE Member Countries on the continent are described, together with emerging problems which confront the Veterinary Services of the continent, namely: exotic diseases, abnormal occurrence of endemic diseases subject to control programmes, faults in food-safety mechanisms, diseases which have an environmental impact, and problems connected with animal welfare. The emergencies which present the greatest risk to South America are foot and mouth diseases, transmissible spongiform encephalopathies, the porcine reproductive and respiratory syndrome, food poisoning, Newcastle disease and fowl plague. Other problems are the appearance of new strains of existing agents, and the presence of resistant individuals among species of bacteria or harmful arthropods. The authors emphasise the need to co-ordinate the prevention of emergencies with development work at the international level, particularly regional and international agreements, harmonization of procedures, progress in animal health and public health, risk analysis, etc. These systems and methods of prevention have a contribution to make in enhancing the potential of animal production in South America, and the adoption of stricter health and quality standards, according to criteria established by the WTO Agreement on the Application of Sanitary and Phytosanitary Measures.

Animal Diseases↗

Human T cell lymphotropic viruses (HTLV-I/II) in South America: should it be a public health concern?

The presence of the human T cell lymphotropic virus (HTLV-I/II) in South America is well established. Its origin and spectrum in the continent still remain a matter of debate. There are signs now that HTLV-I/II was already present in the Amerindian population coming originally from Asia and that HTLV-I was also introduced with African slave trade and with immigration of individuals from endemic areas of Japan. South America has approximately 350 million inhabitants in its 13 countries. The presence of HTLV-I/II has been reported with impressive numbers in most of them and may be considered endemic in this continent. The distribution of HTLV I/II among native Amerindian populations has shown a geographic clustering of type I in the Andean highlands and Brazilian coast, while type II predominates in lowlands of South America. Although comparability between studies conducted among blood donors in different countries may be difficult, the data indicate that the viruses are also circulating among otherwise healthy individuals. Undoubtedly, HTLV-I/II infection and its related diseases should be considered a public health concern in South America and measures to prevent its spread should be emphasized.

Female↗

Occurrence of ochratoxin A in wine and ochratoxigenic mycoflora in grapes and dried vine fruits in South America.

Grape and wine production in South America represents about 6.6% and 10% respectively of the world grape and wine production. The available information on the ochratoxigenic mycoflora and ochratoxin A (OTA) presence in wine grapes, wines, grape juices and dried vine fruits is limited. Surveys have been carried out in Argentina and Brazil which showed that Aspergillus niger aggregate are predominant in the Argentinean varieties while from the Brazilian varieties the species A. niger, Aspergillus ochraceus and Aspergillus carbonarius were isolated. A mycobiota survey from wine grapes in Argentina showed that while Alternaria alternata was predominant, Aspergillus section Nigri species were isolated from 60% of samples. About 41% of black Aspergilli isolates produced OTA with levels ranging from 2 to 24.5 ng mL(-1). In another study, about 83% of A. carbonarius isolates from dried vine fruits produced OTA, with levels ranging from 2 to 5200 ng mL(-1). A survey of grape juices and wines of Brazilian, Argentinean and Chilean origin were found to contain very low levels of OTA. Studies are in progress in Latin America on the ecophysiology of ochratoxigenic fungi and OTA occurrence to reduce the impact of this toxin in the food chain.

Aspergillus↗

Characteristic distribution of HTLV type I and HTLV type II carriers among native ethnic groups in South America.

To confirm the geographic and ethnic segregation of HTLV-I and HTLV-II carriers in native populations in South America, we have conducted a seroepidemiological study of native populations in South America, including HTLV-I carriers distributed among seven ethnic groups in the Andes highlands of Colombia, Peru, Bolivia, Argentina, and Chile, and two ethnic groups on Chiloe Island and Easter Island; and HTLV-II carriers distributed among seven ethnic groups of the lowlands along the Atlantic coast of Colombia, Orinoco, Amazon, and Patagonia, and one ethnic group on Chiloe Island. The incidence rate of HTLV-I and HTLV-II carriers varied among the ethnic groups, ranging from 0.8 to 6.8% for HTLV-I seropositivity and from 1.4 to 57.9% for HTLV-II seropositivity. A new HTLV-I focus was found among the Peruvian Aymara (1.6%), the Bolivian Aymara (5.3%) and Quechua (4.5%), the Argentine Puna (2.3%), and the Chilean Atacama (4.1%), while on HTLV-II focus was found among the Brazilian Kayapo (57.9%), the Paraguayan Chaco (16.4%), and the Chilean Alacalf (34.8%) and Yahgan (9.1%). The distribution of HTLV-I/II foci showed a geographic clustering of HTLV-I foci in the Andes highlands and of HTLV-II foci in the lowlands of South America. It was thus suggested that South American natives might be divided into two major ethnic groups by HTLV-I and HTLV-II carrier state.

Adolescent↗