Two Decades of Wildlife Pathogen Surveillance: Case Study of Choclo orthohantavirus and Its Wild Reservoir Oligoryzomys costaricensis.

The Costa Rican pygmy rice rat (Oligoryzomys costaricensis) is the primary reservoir of Choclo orthohantavirus (CHOV), the causal agent of hantavirus disease, pulmonary syndrome, and fever in humans in Panama. Since the emergence of CHOV in early 2000, we have systematically sampled and archived rodents from >150 sites across Panama to establish a baseline understanding of the host and virus, producing a permanent archive of holistic specimens that we are now probing in greater detail. We summarize these collections and explore preliminary habitat/virus associations to guide future wildlife surveillance and public health efforts related to CHOV and other zoonotic pathogens. Host sequences of the mitochondrial cytochrome b gene form a single monophyletic clade in Panama, despite wide distribution across Panama. Seropositive samples were concentrated in the central region of western Panama, consistent with the ecology of this agricultural commensal and the higher incidence of CHOV in humans in that region. Hantavirus seroprevalence in the pygmy rice rat was >15% overall, with the highest prevalence in agricultural areas (21%) and the lowest prevalence in shrublands (11%). Host-pathogen distribution, transmission dynamics, genomic evolution, and habitat affinities can be derived from the preserved samples, which include frozen tissues, and now provide a foundation for expanded investigations of orthohantaviruses in Panama.

The association between hantavirus infection and selenium deficiency in mainland China.

Hemorrhagic fever with renal syndrome (HFRS) caused by hantaviruses and transmitted by rodents is a significant public health problem in China, and occurs more frequently in selenium-deficient regions. To study the role of selenium concentration in HFRS incidence we used a multidisciplinary approach combining ecological analysis with preliminary experimental data. The incidence of HFRS in humans was about six times higher in severe selenium-deficient and double in moderate deficient areas compared to non-deficient areas. This association became statistically stronger after correction for other significant environment-related factors (low elevation, few grasslands, or an abundance of forests) and was independent of geographical scale by separate analyses for different climate regions. A case-control study of HFRS patients admitted to the hospital revealed increased activity and plasma levels of selenium binding proteins while selenium supplementation in vitro decreased viral replication in an endothelial cell model after infection with a low multiplicity of infection (MOI). Viral replication with a higher MOI was not affected by selenium supplementation. Our findings indicate that selenium deficiency may contribute to an increased prevalence of hantavirus infections in both humans and rodents. Future studies are needed to further examine the exact mechanism behind this observation before selenium supplementation in deficient areas could be implemented for HFRS prevention.

Public health and vector-borne diseases - a new concept for risk governance.

Public Health is defined as an interdisciplinary multilevel approach that deals with questions of preventing diseases at the population level. In this context, this paper focuses on vector-borne diseases as an important threat with an increasing impact on human and animal health. Emphasis is laid on an integrated health approach ('One-Health' initiative) as it recognizes the interrelated nature of both human and animal health. The importance of vector-borne diseases to new and emerging diseases in Europe was demonstrated, for example, by the recent outbreak of West Nile virus infections in Greece, Northern Italy and Hungary; the spread of Crimean-Congo haemorrhagic fever virus across Turkey, south-western countries of the former USSR and the Balkans; the dramatic increase in hantavirus infections in Germany in 2012; and the dengue virus outbreak in Portugal in the same year. This paper provides a systematic approach for the analysis, assessment and governance of emerging health risks attributed to vector-borne diseases by using a holistic approach developed by the International Risk Governance Council (IRGC), called the 'IRGC Risk Governance Framework'. It can be used by decision-makers and general Public Health authorities in order to evaluate the situation regarding any specific pathogen or Public Health risk and to decide if additional measures should be implemented.

Perfil clínico epidemiológico de infección por hantavirus en la Provincia de Buenos Aires, Argentina, periodo 1996 – 2009 / Clinical epidemiological profile hantavirus infection the Buenos Aires province, Argentina, during 1996-2009

Introducción: La infección denominada hantavirus es considerada una zoonosis viral. Se han identificado más de 21 especies en todo el mundo, transmitidas por diferentes roedores, que son su reservorio natural. Argentina hasta el año 2004 fue el país con mayor incidencia en América del Sur siendo Buenos Aires una de las provincias de mayor incidencia del país. Objetivo: El objetivo del presente trabajo fue analizar las variables clínico-epidemiológicas de la enfermedad en la Provincia de Buenos Aires analizando la serie histórica de 14 años (1996-2009). Material y método: Se analizaron 704 fichas de notificación clínica-epidemiológica. La detección serológica de anticuerpos se realizó mediante Elisa. Las variables estudiadas fueron sexo, edad, residencia según partido y región sanitaria, semana epidemiológica (SE), tasa de incidencia y letalidad, evolución clínica y la presencia de diferentes síndromes. Resultados: 622 casos (88.3 por ciento) presentaron estudio de laboratorio serológico, siendo 291 los casos (46.8 por ciento) positivos o confirmados con IgM. Analizando la evolución clínica, (194 pacientes con dato, 67 por ciento) 112 pacientes curaron y 79 fallecieron. La edad promedio de pacientes fallecidos fue de 33 años. La letalidad para cada síndrome fue: gripal 39.9 por ciento, respiratorio 42.1 por ciento con el, renal 43.9 por ciento, hepático 38.5 por ciento, neurológico 57.1 por ciento y hematológico 40 por ciento. El estudio resulta un aporte al conocimiento de la prevalencia del perfil clínico epidemiológico del hantavirus en la Provincia de Buenos Aires, Argentina.

Introduction: Hantavirus infection is considered a viral zoonosis. More than 21 species have been indentified throughout the world, transmitted by different rodents, which are its natural reservoir. Until 2004, Argentina was the country with the highest incidence in South America, Buenos Aires being one of the provinces with the highest incidence in the country. Objective: The objective of this study was to analyze the clinical and epidemiological variables of the disease in the Buenos Aires Province, analyzing 14 years of historical trends (1996-2009). Materials and methods: 704 clinical-epidemiological notifications were analyzed. Serological detection of antibodies was carried out using ELISA. The variables studied were sex, age, residence according to health system district, epidemiological week (EW), incidence rate, lethality, clinical evolution, and the presence of different syndromes. Results: 622 cases (88.3 percent) had a laboratory serological report, 291 (46.8 percent) of those being positive cases or those confirmed with IgM. Analyzing clinical evolution, (194 patients included this data, 67 percent) 112 patients were cured y 79 died. The average age of deceased patients was 33 years. Lethality for each syndrome was: influenza 39.9 percent, respiratory 42.1 percent, renal 43.9 percent, hepatic 38.5 per cent, neurological 57.1 percent y hematological 40 per cent. This study contributes to knowledge of the clinical epidemiological profile of hantavirus in Buenos Aires Province, Argentina.

Hantavirus infections in Europe: from virus carriers to a major public-health problem.

In Europe, hantavirus disease or hemorrhagic fever with renal syndrome is an endemic zoonosis that affects tens of thousands of individuals each year. The causative agents are viruses of the genus Hantavirus, family Bunyaviridae, rodents and insectivores act as carriers. In all European countries there is a seroprevalence for hantaviruses in the general population but not all countries report cases. Here, we give an overview of the hantavirus situation in Europe.