Emerging hantaviruses in Central Argentina: First case of Hantavirus Pulmonary Syndrome caused by Alto Paraguay virus, and a novel orthohantavirus in Scapteromys aquaticus rodent

Orthohantaviruses are emerging rodent-borne pathogens that cause Hantavirus Pulmonary Syndrome in humans. They have a wide range of rodent reservoir hosts and are transmitted to humans through aerosolized viral particles generated by the excretions of infected individuals. Since the first description of HPS in Argentina, new hantaviruses have been reported throughout the country, most of which are pathogenic to humans. We present here the first HPS case infected with Alto Paraguay virus reported in Argentina. Until now, Alto Paraguay virus was considered a non-pathogenic orthohantavirus since it was identified in a rodent, Holochilus chacarius. In addition to this, with the goal of identifying potential hantavirus host species in the province of Santa Fe, we finally describe a novel orthohantavirus found in the native rodent Scapteromys aquaticus, which differed from other hantaviruses described in the country so far. Our findings implicate an epidemiological warning regarding these new orthohantaviruses circulating in Central Argentina as well as new rodent species that must be considered as hosts from now on.

Case Report: First Confirmed Case of Coinfection of SARS-CoV-2 With Choclo orthohantavirus

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a major international public health concern. The World Health Organization (WHO) declared the pandemic of coronavirus disease 2019 (COVID-19) on March 11, 2020. In Panama, the first SARS-CoV-2 infection was confirmed on March 9, 2020, and the first fatal case associated to COVID-19 was reported on March 10. This report presents the case of a 44-year-old female who arrived at the hospital with a respiratory failure, five days after the first fatal COVID-19 case, and who was living in a region where hantavirus pulmonary syndrome cases caused by Choclo orthohantavirus (CHOV), are prevalent. Thus, the clinical personnel set a differential diagnosis to determine a respiratory disease caused by the endemic CHOV or the new pandemic SARS-CoV-2. This case investigation describes the first coinfection by SARS-CoV-2 and CHOV worldwide. PCR detected both viruses during early stages of the disease and the genomic sequences were obtained. The presence of antibodies was determined during the patient’s hospitalization. After 23 days at the intensive care unit, the patient survived with no sequelae, and antibodies against CHOV and SARS-CoV-2 were still detectable 12 months after the disease. The detection of the coinfection in this patient highlights the importance, during a pandemic, of complementing the testing and diagnosis of the emergent agent, SARS-CoV-2, with other common endemic respiratory pathogens and other zoonotic pathogens, like CHOV, in regions where they are of public health concern.

Polyclonal alpaca antibodies protect against hantavirus pulmonary syndrome in a lethal Syrian hamster model

The use of antibody-based therapies for the treatment of high consequence viral pathogens has gained interest over the last fifteen years. Here, we sought to evaluate the use of unique camelid-based IgG antibodies to prevent lethal hantavirus pulmonary syndrome (HPS) in Syrian hamsters. Using purified, polyclonal IgG antibodies generated in DNA-immunized alpacas, we demonstrate that post-exposure treatments reduced viral burdens and organ-specific pathology associated with lethal HPS. Antibody treated animals did not exhibit signs of disease and were completely protected. The unique structures and properties, particularly the reduced size, distinct paratope formation and increased solubility of camelid antibodies, in combination with this study support further pre-clinical evaluation of heavy-chain only antibodies for treatment of severe respiratory diseases, including HPS.

Emerging Hantaviruses in Central Argentina: first case of Hantavirus Pulmonary Syndrome caused by Alto Paraguay Virus and a novel orthohantavirus in Scapteromys aquaticus rodent

Orthohantaviruses are emerging rodent-borne pathogens that cause Hantavirus Pulmonary Syndrome in humans. They have a wide range of rodent reservoir hosts and are transmitted to humans through aerosolized viral particles generated by the excretions of infected individuals. Since the first description of HPS in Argentina, new hantaviruses have been reported throughout the country, most of which are pathogenic to humans.We present here the first HPS case infected with Alto Paraguay virus reported in Argentina. Until now, Alto Paraguay virus was considered a non-pathogenic orthohantavirus since it was identified in a rodent, Hollochilus chacarius. In addition to this, with the goal of identifying potential hantavirus host species in the province of Santa Fe, we finally describe a novel orthohantavirus found in the native rodent Scapteromys aquaticus, which differed from other hantaviruses described in the country so far.Our findings implicate an epidemiological warning regarding these new orthohantaviruses circulating in Central Argentina as well as new rodent species that must be considered as hosts from now on.

Continuing Orthohantavirus Circulation in Deer Mice in Western Montana

Hantavirus pulmonary syndrome (HPS) is an often-fatal disease caused by New World hantaviruses, such as Sin Nombre orthohantavirus (SNV). In the US, >800 cases of HPS have been confirmed since it was first discovered in 1993, of which 43 were reported from the state of Montana. The primary cause of HPS in the US is SNV, which is primarily found in the reservoir host Peromyscus maniculatus (deer mouse). The reservoir host covers most of the US, including Montana, where multiple studies found SNV in local deer mouse populations. This study aimed to check the prevalence of SNV in the deer mice at popular recreation sites throughout the Bitterroot Valley in Western Montana as compared to previous studies in western Montana. We found high prevalence (up to 20%) of deer mice positive for SNV RNA in the lungs. We were unable to obtain a SNV tissue culture isolate from the lungs but could passage SNV from lung tissue into naïve deer mice. Our findings demonstrate continuing circulation of SNV in western Montana.

Dengue and hantavirus coinfection with good outcomes: a clinical case from Panama

Dengue and hantavirus are endemic in central Panama. We present a case report of a patient coinfected with dengue and hantavirus who presented overlapping clinical manifestations of both infections. The patient did not require intensive care—as it is commonplace during hantavirus pulmonary syndrome—and he had a good outcome. Patient’s care was positively impacted due to correct diagnosis of coinfection. This case highlights that in endemic areas, coinfection with dengue virus and hantavirus should be suspected. To the best of our knowledge, this case is the first documented case of coinfection with dengue virus and hantavirus in Central America.