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PubMed1993

Ministers of health urge intensified fight against AIDS. Latin America.

Ministers of health from all the countries of the Americas agree there is "an imperative need to mobilize all sectors of the society in the campaign against AIDS." Noting "the growing threat posed by the AIDS epidemic, infection with HIV, and the increase in sexually transmitted diseases," the health ministers urged intensified national efforts to prevent AIDS. The ministers, in Washington, D.C., for the 37th meeting of the Pan American Health Organization's (PAHO) Directing Council, reviewed the latest information on AIDS, which shows that of the more than 700,000 cases of AIDS worldwide, more than half occur in the Americas. PAHO experts estimate there are 2.5 million HIV-infected people in the Americas, including 1 million in North America and 1.5 million in Latin America and the Caribbean. There are indications the infection is continuing to spread rapidly. "A significant increase in the number of AIDS cases is expected in the coming years, particularly in Latin American and the Caribbean," and the AIDS epidemic, in addition to the suffering it inflicts, has enormous direct and indirect costs which must be reduced through preventive actions, according to a report presented at the meeting. In a resolution, the ministers also called for "the best possible coordination of preventive actions at the regional and country level," requesting member governments to "intensify national efforts to prevent HIV, AIDS and sexually transmitted disease and diminish" their social and economic consequences through unified, coordinated actions involving governments and nongovernment organizations in the fight against AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed2006

[The new-world hantaviruses. Ecology and epidemiology of an emerging virus in Latin America].

The hantaviruses are a group of emerging rodent-borne pathogens (family Bunyaviridae; Genus Hantavirus) that are etiologic agents for hemorrhagic fever with renal syndrome (HFRS) in Europe and Asia and hantavirus cardiopulmonary syndrome (HCPS) in the Americas. HFRS is associated with rodents of the family Muridae, subfamilies Murinae and Arvicolinae; HPS is associated with rodents of the subfamily Sigmodontinae. Since the identification of HCPS in USA in 1993, a large number of cases of HPS and an increasing number of hantaviruses and rodent reservoir hosts have been identified in Central and South America. Epidemiologic studies have demonstrated important differences in frequency of infection with hantaviruses in both human and rodent host populations. Antibody prevalences in rodent and human populations may vary from less than 1% to more than 40%. Currently, more than 1500 cases of HCPS have been reported and more than 15 genetically distinct variants of hantaviruses, all associated with sigmodontine rodents, have been identified throughout the Americas. Several characteristics distinguish Latin American HCPS cases from the classical HCPS described for the first time in the USA. These include a variation in severity of disease from moderate and self-limiting to severe, the demonstration of person-to-person transmission, and a somewhat higher incidence of extrapulmonary clinical manifestations in the South American form of HCPS. Nevertheless, our understanding of hantaviruses in the Americas is still far from complete. The factors involved in the dynamics of these viruses in nature, their establishment and transmission within host populations and from hosts to humans, and the variable pathology of these viruses in humans are complex. It is likely that more hantaviruses will be described in the future, and much more data will be required in order to describe the diversity and evolution of this group of pathogens. Latin America, as the center of diversity for Sigmodontine rodents and their hantaviruses is presented with the unique opportunity as well as the challenge of being center stage for continued studies of the dynamics of hantaviruses in natural host populations and the links of host and virus to human populations.

Animals↗
PubMed2002

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↗
PubMed1996

Trends in cervical cancer mortality in the Americas.

This article presents an assessment of cervical cancer mortality trends in the Americas based on PAHO data. Trends were estimated for countries where data were available for at least 10 consecutive years, the number of cervical cancer deaths was considerable, and at least 75% of the deaths from all causes were registered. In contrast to Canada and the United States, whose general populations had been screened for many years and where cervical cancer mortality has declined steadily (to about 1.4 and 1.7 deaths per 100,000 women, respectively, as of 1990), most Latin American and Caribbean countries with available data have experienced fairly constant levels of cervical cancer mortality (typically in the range of 5-6 deaths per 100,000 women). In addition, several other countries (Chile, Costa Rica, and Mexico) have exhibited higher cervical cancer mortality as well as a number of noteworthy changes in this mortality over time. Overall, while actual declining trends could be masked by special circumstances in some countries, cervical cancer mortality has not declined in Latin America as it has in developed countries. Correlations between declining mortality and the intensity of screening in developed countries suggest that a lack of screening or screening program shortcomings in Latin America could account for this. Among other things, where large-scale cervical cancer screening efforts have been instituted in Latin America and Caribbean, these efforts have generally been linked to family planning and prenatal care programs serving women who are typically under 30; while the real need is for screening of older women who are at substantially higher risk.

Adult↗
PubMed1996

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↗
PubMed2005

Radiotherapy for invasive breast cancer in North America and Europe: results of a survey.

PURPOSE: To document and explain the current radiotherapeutic management of invasive breast cancer in North America and Europe. We also identified a number of areas of agreement, as well as controversy, toward which additional clinical research should be directed. METHODS AND MATERIALS: An original survey questionnaire was developed to assess radiation oncologists' self-reported management of breast cancer. The questionnaire was administered to physician members of the American Society for Therapeutic Radiology and Oncology and the European Society for Therapeutic Radiology and Oncology. We present the results of the comparative analysis of 702 responses from North America and 435 responses from Europe. RESULTS: Several areas of national and international controversy were identified, including the selection of appropriate candidates for postmastectomy radiation therapy (RT) and the appropriate management of the regional lymph nodes after mastectomy, as well as after lumpectomy. Only 40.7% and 36.1% of respondents would use postmastectomy RT in patients with 1-3 positive lymph nodes in North America and Europe, respectively. Sentinel lymph node biopsy was offered more frequently by North American than European respondents (p <0.0001) and more frequently by academic than nonacademic respondents in North America (p < 0.05). The average radiation fraction size was larger in Europe than in North America (p < 0.01). European respondents offered RT to the internal mammary chain more often than did the North American respondents (p < 0.001). North American respondents were more likely to offer RT to the supraclavicular fossa (p < 0.001) and axilla (p < 0.01). CONCLUSION: Marked differences were found in physician opinions regarding the management of breast cancer, with statistically significant international differences in patterns of care. This survey highlighted areas of controversy, providing support for international randomized trials to optimize the RT management of invasive breast cancer.

Breast Neoplasms↗
PubMed2005

Genetic and biologic characteristics of Toxoplasma gondii isolates in free-range chickens from Colombia, South America.

The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 77 free-range chickens (Gallus domesticus) from Colombia, South America was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT), and found in 32 (44.4%) of 72 chickens with titers of 1:5 in 4, 1:10 in 3, 1:20 in 1, 1:40 in 1, 1:80 in 8, 1:160 in 8, 1:320 in 3, and 1:640 or higher in 4. Hearts and brains of 31 seropositive chickens were pooled and bioassayed in mice. Tissues from 32 (16+16) seronegative chickens were pooled and fed to two, T. gondii-free cats, and tissues from nine chickens without matching sera were fed to one T. gondii-free cat. Feces of cats were examined for oocysts. T. gondii oocysts were excreted by a cat that was fed tissues of 16 seronegative chickens. T. gondii was isolated by bioassay in mice from 23 chickens with MAT titers of 1:20 or higher. All infected mice from 16 of the 23 isolates died of toxoplasmosis. Overall, 82 (81.1%) of 101 mice that became infected after inoculation with chicken tissues died of toxoplasmosis. Genotyping of these 24 isolates using polymorphisms at the SAG2 locus indicated that seven T. gondii isolates were Type I, 17 were Type III, and none was Type II. Phenotypically, T. gondii isolates from chickens from Colombia were similar to isolates from Brazil but different from the isolates from North America; most isolates from chickens from Brazil and Colombia were lethal for mice whereas isolates from North America did not kill inoculated mice. Genetically, none of the T. gondii isolates from Colombia and Brazil was SAG2 Type II, whereas most isolates from chickens from North America were Type II. This is the first report of genetic characterization of T. gondii isolates from Colombia, South America.

Agglutination Tests↗
PubMed1993

Characterization of Anopheles pseudopunctipennis sensu lato from three countries of neotropical America from variation in allozymes and ribosomal DNA.

Enzyme electrophoresis and restriction fragment length polymorphism (RFLP) analysis of Anopheles pseudopunctipennis sensu lato from nine isolated populations in neotropical America confirmed previous observations that it constitutes a species complex. Electrophoretic studies showed fixed differences at two enzyme loci, glycerol dehydrogenase (Gcd) and phosphoglucomutase (Pgm), suggesting limited or no gene flow between populations from Mexico and South America. In addition, analysis of genetic distance showed two distinctive clusters, one from Mexico and the other from South America, separated at a Nei's distance level of 0.13, a value consistent in magnitude with that of other anopheline sibling species. The RFLP analysis revealed the presence of a ribosomal DNA fragment in Mexican strains that was absent in strains from South America. Two species have been identified through these studies, one provisionally named An. pseudopunctipennis A, a species from central Mexico, and the other An. pseudopunctipennis B, for the species found in the interAndean valleys and Andean slopes in regions of Peru and Bolivia. This research provides information required to elucidate the status of the different species of the An. pseudopunctipennis complex as vectors of malaria in the Americas.

Alleles↗
PubMed2025

The landscape of suicide risk factors in Latin America.

Suicide is a leading cause of death globally, with over 75&#x2009;% of cases occurring in low- and middle-income countries (LMICs). Latin America, a severely underrepresented region in suicide research, has experienced a 6&#x2009;% increase in its suicide rate from 2010 to 2016, contrasting with a global decline. In this commentary, we provide an overview of the epidemiological, social, and clinical factors influencing suicide in Latin America. We highlight the distinct trends in Latin America compared to other world regions, including the significant disparities in mental health care accessibility. Our review also considers the role of sociocultural factors such as strong family ties, traditional gender norms, and the impact of religiosity on stigma and care-seeking behaviors. Additionally, we address the lack of representation of Latin American populations in genetic studies on suicide, which hinders the identification of relevant biological markers and the development of tailored interventions. We call for increased research on the clinical, genetic, and social determinants of suicide in this region to better understand risk factors and ultimately inform suicide prevention strategies. Addressing this gap is critical for reducing suicide rates in Latin America.

Humans↗
PubMed2001

Spectrum and activity of three contemporary fluoroquinolones tested against Pseudomonas aeruginosa isolates from urinary tract infections in the SENTRY Antimicrobial Surveillance Program (Europe and the Americas; 2000): more alike than different!

The spectrum and potency of ciprofloxacin, gatifloxacin and levofloxacin was compared to that of 10 other agents against urinary tract isolates of Pseudomonas aeruginosa among patients in the year 2000 SENTRY Antimicrobial Surveillance Program (Europe, Latin America, North America). Dramatic differences were observed between isolates in geographic areas with the most fluoroquinolone-resistant strains detected in Latin America (54.5% resistance) compared to resistance rates of 40.8-43.7% and 28.3-29.2% for Europe and North America, respectively. Overall, no significant differences were observed between the spectrums of these fluoroquinolones (37.1-38.8% resistance) for therapy of P. aeruginosa urinary tract infections in hospitalized patients. Generally, in this world wide sample, aminoglycosides, carbapenems (imipenem, meropenem), cefepime, and piperacillin with or without tazobactam possessed a wider range of activity and spectrum versus current P. aeruginosa clinical isolates.

Aminoglycosides↗
PubMed2006

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↗
PubMedDate not supplied

Diarrhea and respiratory symptoms among travelers to Asia, Africa, and South and Central America from Scotland.

Surveillance using admissions to hospital, while being useful, is a poor indicator of the real incidence of disease encountered by travelers. An alternative is self-reported illness among those who attended at a pretravel clinic prior to their travels. Estimates of incidence and risk factors were determined for attendees at a travel clinic in Scotland using a questionnaire. Analysis for risk factors was carried out for those travelers visiting countries in Africa, Asia, or South and Central America, who had traveled for 1 week or more and had returned between 1997 and 2001 (N= 4,856). Multivariate logistic regression was used to test the hypotheses that time abroad and age-group would be significant for both respiratory and diarrheal symptoms regardless of which of the three geographical areas are visited. From 2006 returned questionnaires (response rate = 41.3%), diarrhea and respiratory symptoms were reported by 44.2 and 16.8% of respondents, respectively; the incidence was significantly greater among travelers to Asia for both diarrheal (55.5%) and respiratory (23.7%) symptoms than among travelers to Africa (36.6 and 12.2%, respectively) or South and Central America (39.5 and 16.2%, respectively). For diarrhea, age was a highly significant risk factor for travelers to Asia, South and Central America, and Africa. Being a self-organized tourist/backpacker, traveling to Asia was associated with increased risk, while for Africa and South and Central America visiting family or friends was associated with a lower risk. For travelers to Asia, traveling to the Indian subcontinent was significantly associated with increased risk. The majority of travelers had an adverse event while traveling abroad, with diarrhea and respiratory conditions being especially common despite attending a travel clinic for advice prior to departure. However, the limitations of this surveillance-based strategy have highlighted the requirement for more research to understand more fully the issues of risk and incidence among travelers to high-risk destinations from Scotland.

Adolescent↗
PubMed2002

Colonization models and initial genetic diversity in the Americas.

The mode and tempo of colonization of the Americas established the initial pattern of continental genetic diversity. Despite a long history of study, the process of settlement remains controversial in terms of date, rate, and pattern. While there is agreement that Asia was the source population, several different models have been proposed for the colonization process. A classic model postulates a rapid spread of population ("blitzkrieg") from a small band of hunters entering through the corridor between the continental ice sheets circa 11,000 years B.P. Colonization occurred as a wave of expansion across the land masses of North and South America. An alternative model envisions the original colonists initially limiting settlement to the coastline, using boats, and entering the Americas at an earlier date, circa 13,500 B.P. Range expansion along this linear habitat from North to South America could be rapid without requiring population saturation of entire continental regions. These models have markedly different implications for genetic variation among Native Americans. The blitzkrieg colonization process would have generated multiple founder effects leading to extreme loss of genetic variation. Computer simulation of this model shows nearly complete fixation in 30 generations. Simulation of the coastal model, on the other hand, requires less extreme demographic assumptions and maintains substantial genetic variability after 100 generations. Although with the coastal model continental interiors are occupied less rapidly than with the blitzkrieg model, the coastal model allows earlier entry and rapid expansion to the southern limits of the hemisphere.

Emigration and Immigration↗
PubMedDate not supplied

A subregional assessment of demographic and health trends in the Americas: 1980-1998.

Close to 14 percent of the world's population lives in the Americas and the total population of this area is expected to reach 823,225,000 by the year 2000. Periodic assessments of the health situation and trends in conditions throughout subregions of the Americas have been undertaken by the Pan American Health Organization (PAHO) since the mid-1950s. These assessments demonstrate and underscore some major disparities in social, health and economic conditions in the various countries within the region. Analysis of some 38 demographic, socioeconomic, vital statistics and resource availability indicators show encouraging health and social progress between 1980 and 1998. Data concerning the health situation and trends in eight subregions of the Americas show a demographic reshape and an overall improvement in a variety of health indicators over this period. Important changes occurred in the epidemiological profile of the populations, shifting from a mainly communicable disease profile to one in which chronic diseases also affect a major portion of the population. This double health burden is unique in the region of the Americas. Improvements in social as well as health indicators were evidenced throughout the various subregions but at differing levels and at varying rates. Marked changes in total fertility, infant mortality, life expectancy and morbidity rates characterized the period between 1980 and 1998. The discrepancies between countries are highlighted and areas in need of further improvement outlined.

Americas↗
PubMed2006

Adherence to antiretroviral therapy in sub-Saharan Africa and North America: a meta-analysis.

CONTEXT: Adherence to antiretroviral therapy is a powerful predictor of survival for individuals living with human immunodeficiency virus (HIV) and AIDS. Concerns about incomplete adherence among patients living in poverty have been an important consideration in expanding the access to antiretroviral therapy in sub-Saharan Africa. OBJECTIVE: To evaluate estimates of antiretroviral therapy adherence in sub-Saharan Africa and North America. DATA SOURCES: Eleven electronic databases were searched along with major conference abstract databases (inclusion dates: inception of database up until April 18, 2006) for all English-language articles and abstracts; and researchers and treatment advocacy groups were contacted. Study Selection and Data Abstraction To best reflect the general population, studies of mixed populations in both North America and Africa were selected. Studies evaluating specific populations such as men only, homeless individuals, or drug users, were excluded. The data were abstracted in duplicate on study adherence outcomes, thresholds used to determine adherence, and characteristics of the populations. A random-effects meta-analysis was performed in which heterogeneity was examined using multivariable random-effects logistic regression. A sensitivity analysis was performed using Bayesian methods. DATA SYNTHESIS: Thirty-one studies from North America (28 full-text articles and 3 abstracts) and 27 studies (9 full-text articles and 18 abstracts) from sub-Saharan Africa were included. African studies represented 12 sub-Saharan countries. Of the North American studies, 71% used patient self-report to assess adherence; this was true of 66% of the African assessments. Studies reported similar thresholds for adherence monitoring (eg, 100%, >95%, >90%, >80%). A pooled analysis of the North American studies (17,573 patients total) indicated a pooled estimate of 55% (95% confidence interval, 49%-62%; I2, 98.6%) of the populations achieving adequate levels of adherence. Our pooled analysis of African studies (12,116 patients total) indicated a pooled estimate of 77% (95% confidence interval, 68%-85%; I2, 98.4%). Study continent, adherence thresholds, and study quality were significant predictors of heterogeneity. Bayesian analysis was used as an alternative statistical method for combining adherence rates and provided similar findings. CONCLUSION: Our findings indicate that favorable levels of adherence, much of which was assessed via patient self-report, can be achieved in sub-Saharan African settings and that adherence remains a concern in North America.

Africa South of the Sahara↗
PubMed2005

Population genetic analysis of cat populations from Mexico, Colombia, Bolivia, and the Dominican Republic: identification of different gene pools in Latin America.

In this paper we identify new genetic profiles of eight Latin American cat populations. In addition, we combine data from the present study and previously published data on 70 other American and European populations to discuss (1) the points of introduction of mutant alleles for cat coat phenotypes from Europe into Latin America, (2) the heterozygosity levels at these loci in the current Latin American cat populations, (3) the level of genetic heterogeneity among Latin American cat populations, and how this compares with levels found in North American and European cat populations, and (4) how many different cat gene pools are currently present in Latin America. We also include in our purview historical records of human migrations from Europe to and within the Americas. Our analyses clearly support the view that the current genetic profiles and structuring of cat populations in Latin America can be largely explained by the historical migration patterns of humans.

Alleles↗
PubMed2005

Histoplasmosis infection in Spanish travelers to Latin America.

The aim of the study presented here was to assess the incidence of histoplasma infection in a cohort of 342 individuals in Spain who had traveled to Latin America for the first time. The histoplasmin skin test was positive in 20% of the travelers, and Central America posed a higher risk for infection than South America (p=0.013). Sleeping outdoors (p=0.031) and the duration of travel (p=0.016) were also identified as significant risk factors. Serological testing demonstrated poor overall sensitivity for detecting infection in the travelers, but for the symptomatic acute cases the results were improved. Histoplasmosis must be considered in patients presenting with fever (odds ratio=3.51 [1.52-8.12]) or cough (odds ratio=4.24 [1.32-13.58]) after visiting Latin America. The results of this study have public health implications and indicate the risks of acquiring histoplasmosis should be included in pre-travel counseling.

Adult↗
PubMed2006

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↗