Search results for "Orthohantavirus"

Quasispecies dynamics and fixation of a synonymous mutation in hantavirus transmission.

2008

RNA-dependent RNA polymerases, the key enzymes in replication of RNA viruses, have a low fidelity; thus, these viruses replicate as a swarm of mutants termed viral quasispecies. Constant generation of new mutations allows RNA viruses to adapt swiftly to a novel environment through selection of both pre-existing and de novo-generated genetic variants. Here, quasispecies dynamics were studied in vivo in controlled hantavirus transmission from experimentally infected to naïve rodents through infested cage bedding. An elementary step of virus microevolution was apparent, as one synonymous mutation (A759G) repeatedly became fixed in the viral RNA quasispecies populations in the recipient animals.

Chimaeric HBV core particles carrying a defined segment of Puumala hantavirus nucleocapsid protein evoke protective immunity in an animal model

1998

Abstract Hantaviruses are rodent-born agents which are pathogenic in humans causing haemorrhagic fever with renal syndrome or hantavirus pulmonary syndrome. To induce a protective immunity against a European hantavirus (Puumala) we constructed chimaeric hepatitis B virus (HBV) core particles carrying defined fragments of the Puumala virus nucleocapsid protein. After immunisation of bank voles, the natural host of Puumala virus, with core particles possessing an insertion of the N-terminal part of Puumala virus nucleocapsid protein, four of five animals were protected against subsequent virus challenge. The results show that the major protective region of the nucleocapsid protein is located …

Hantavirus infections in fluctuating host populations: the role of maternal antibodies.

2010

Infected females may transfer maternal antibodies (MatAbs) to their offspring, which may then be transiently protected against infections the mother has encountered. However, the role of maternal protection in infectious disease dynamics in wildlife has largely been neglected. Here, we investigate the effects of Puumala hantavirus (PUUV)-specific MatAbs on PUUV dynamics, using 7 years' data from a cyclic bank vole population in Finland. For the first time to our knowledge, we partition seropositivity data from a natural population into separate dynamic patterns for MatAbs and infection. The likelihood of young of the year carrying PUUV-specific MatAbs during the breeding season correlated p…

Cyclic hantavirus epidemics in humans--predicted by rodent host dynamics.

2009

Wildlife-originated zoonotic diseases are a major contributor to emerging infectious diseases. Hantaviruses cause thousands of human disease cases annually worldwide, and understanding and predicting human hantavirus epidemics still poses unsolved challenges. Here we studied the three-level relationships between the human disease nephropathia epidemica (NE), its etiological agent Puumala hantavirus (PUUV) and the rodent host of the virus, the bank vole (Myodes glareolus). A large and long-term data set (14 years, 2583 human NE cases and 4751 trapped bank voles) indicates that the number of human infections shows both seasonal and multi-annual fluctuations, is influenced by the phase of vole…

An amino-terminal segment of hantavirus nucleocapsid protein presented on hepatitis B virus core particles induces a strong and highly cross-reactive…

2004

AbstractPreviously, we have demonstrated that hepatitis B virus (HBV) core particles tolerate the insertion of the amino-terminal 120 amino acids (aa) of the Puumala hantavirus nucleocapsid (N) protein. Here, we demonstrate that the insertion of 120 amino-terminal aa of N proteins from highly virulent Dobrava and Hantaan hantaviruses allows the formation of chimeric core particles. These particles expose the inserted foreign protein segments, at least in part, on their surface. Analysis by electron cryomicroscopy of chimeric particles harbouring the Puumala virus (PUUV) N segment revealed 90% T = 3 and 10% T = 4 shells. A map computed from T = 3 shells shows additional density splaying out …

New chimaeric hepatitis B virus core particles carrying hantavirus (serotype Puumala) epitopes: immunogenicity and protection against virus challenge

1999

Virus-like particles generated by the heterologous expression of virus structural proteins are able to potentiate the immunogenicity of foreign epitopes presented on their surface. In recent years epitopes of various origin have been inserted into the core antigen of hepatitis B virus (HBV) allowing the formation of chimaeric HBV core particles. Chimaeric core particles carrying the 45 N-terminal amino acids of the Puumala hantavirus nucleocapsid protein induced protective immunity in bank voles, the natural host of this hantavirus. Particles applied in the absence of adjuvant are still immunogenic and partially protective in bank voles. Although a C-terminally truncated core antigen of HBV…

Experimental investigation of a hantavirus host-switch between arvicoline rodents Lemmus lemmus and Myodes glareolus

2014

Serological Survey of Rodent-Borne Viruses in Finnish Field Voles

2014

In northern Europe, rodent populations display cyclic density fluctuations, which can be correlated with the human incidence of zoonotic diseases they spread. During density peaks, field voles (Microtus agrestis) become one of the most abundant rodent species in northern Europe, yet little is known of the viruses they host. We screened 709 field voles, trapped from 14 sites over three years, for antibodies against four rodent-borne, potentially zoonotic viruses or virus groups: hantaviruses, lymphocytic choriomeningitis virus (LCMV), Ljungan virus (LV) and orthopoxviruses (OPV). Antibodies against all four viruses were detected. However, seroprevalence of hantaviruses, LV and LCMV was low. …

The impact of wildlife and environmental factors on hantavirus infection in the host and its translation into human risk

2023

Identifying factors that drive infection dynamics in reservoir host populations is essential in understanding human risk from wildlife-originated zoonoses. We studied zoonotic Puumala orthohantavirus (PUUV) in the host, the bank vole ( Myodes glareolus ), populations in relation to the host population, rodent and predator community and environment-related factors and whether these processes are translated into human infection incidence. We used 5-year rodent trapping and bank vole PUUV serology data collected from 30 sites located in 24 municipalities in Finland. We found that PUUV seroprevalence in the host was negatively associated with the abundance of red foxes, but this process did no…

A hantavirus nucleocapsid protein segment exposed on hepatitis B virus core particles is highly immunogenic in mice when applied without adjuvants or…

2005

Hepatitis B virus (HBV) core particles carrying the amino-terminal 120 amino acids (aa) of the nucleocapsid (N) protein of the hantaviruses Dobrava, Hantaan or Puumala have been demonstrated to be highly immunogenic in mice when complexed with adjuvants. Here we demonstrate that even without adjuvant, these chimeric particles induced high-titered, and strongly cross-reactive N-specific antibody responses in BALB/c and C57BL/6 mice. The induced N-specific antibodies represented all IgG subclasses. Pre-existing core-specific antibodies did not abrogate the induction of an N-specific immune response by a hantavirus N insert presented on core particles. Therefore, chimeric core particles should…