Pathogenesis of hemorrhagic fever with renal syndrome virus infection and mode of horizontal transmission of hantavirus in bank voles

ABSTRACT:Sin Nombre virus (SNV), hosted by the deer mouse (Peromyscus maniculatus), is the principal cause of hantavirus pulmonary syndrome (HPS) in North America. To improve our understanding of factors that contribute to the occurrence of HPS, we conducted an extensive field study of the characteristics of newly infected (as determined by recent acquisition of antibody) deer mice and the temporal pattern of antibody acquisition (seroconversion) from 1994 through 2004 in Montana, USA. We sampled 6,584 individual deer mice, of which 2,747 were captured over multiple trapping periods. Among these 2,747 deer mice, we detected 171 instances of seroconversion. There was no relationship between seroconversion and the acquisition of scars. However, recently infected Montana deer mice were more likely to be older, more likely to be males, and more likely to be in breeding condition. In addition, recently infected male deer mice gained less weight over the 1-mo period following seroconversion than did those that did not acquire antibody, suggesting that SNV infection may have negatively impacted the health of infected rodents. Incidence was highly variable among years, and timing of infections was primarily associated with the breeding season (generally early spring through late fall).

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Sin Nombre Virus Infection of Deer Mice in Montana: Characteristics of Newly Infected Mice, Incidence, and Temporal Pattern of Infection

Douglass

Calisher

Wagoner

et al. 2007

“…Laboratory studies have demonstrated a consistent pattern of events following hantavirus infections of their natural rodent hosts (Lee et al, 1981;Yanagihara et al, 1985;Gavrilovskaya et al, 1990;Hutchinson et al, 1998;Botten et al, 2000Botten et al, , 2003. First, there is a brief viremia, followed by the development of circulating antibody, and then consequent clearance of virus from the blood.…”

Section: Introductionmentioning

confidence: 94%

“…It has been generally accepted that once a host is infected it will remain infected and infectious (capable of shedding infectious virus into the environment) for the remainder of its life. Although this may be correct, it is likely that the period of occurrence of the highest rate of shedding of SNV from the infected host is during the first several weeks after infection, when virus is shed at the highest titer (Lee et al, 1981;Gavrilovskaya et al, 1990;Hutchinson et al, 1998). This period of infectivity may be quenched by the appearance of neutralizing antibody and the consequent disappearance of infectious virus from the blood.…”

Section: Introductionmentioning

confidence: 99%

Long-Term Dynamics of Sin Nombre Viral Rna and Antibody in Deer Mice in Montana

Kuenzi

Douglass

Bond

et al. 2005

Infections with hantaviruses in the natural host rodent may result in persistent, asymptomatic infections involving shedding of virus into the environment. Laboratory studies have partially characterized the acute and persistent infection by Sin Nombre virus (SNV) in its natural host, the deer mouse (Peromyscus maniculatus). However, these studies have posed questions that may best be addressed using longitudinal studies involving sequential sampling of individual wild-caught, naturally infected mice. Using enzyme immunoassay and polymerase chain reaction (PCR) analysis of monthly blood samples, we followed the infection status of deer mice in a mark-recapture study in Montana for 2 yr. Only six of 907 samples without IgG antibody to SNV contained detectable SNV RNA, suggesting that there is a very brief period of viremia before the host develops detectable antibody. The simultaneous presence of both antibody and viral RNA in blood was detected in consecutive monthly samples for as long as 3 mo. However, chronic infection was typified by alternating characteristics of PCR positivity and PCR negativity. Two possible interpretations of these results are that 1) viral RNA may be consistently present in the blood of chronically infected deer mouse, but that viral RNA is near the limits of PCR detectability or 2) SNV RNA sporadically appears in blood as a consequence of unknown physiological events. The occurrence of seasonal patterns in the proportion of samples that contains antibody and that also contained SNV RNA demonstrated a temporal association between recent infection (antibody acquisition) and presence of viral RNA in blood.

“…Hantaviruses are thought to be contracted by their rodent hosts through passage of urine or saliva via bite wounds during fighting (Glass et al, 1988) or possibly by direct contact with rodents that are virus carriers, contact with their nest material, blood, urine, saliva, or contact with aerosolized virus in closed spaces (Gavrilovskaya et al, 1990). Infectious virus may be shed for the life of the host .…”

Section: Introductionmentioning

confidence: 99%

Relationships of Deer Mouse Movement, Vegetative Structure, and Prevalence of Infection With Sin Nombre Virus

Root

Calisher

Beaty

1999

The effects of vegetative structure on movement of deer mice (Peromyscus maniculatus) were examined in two distinct vegetation associations, one near Hesperus and the other near Molina in western Colorado (USA) from June-October 1994 to October 1998. We monitored movement by live-trapping small mammals within Gambel's oak/mixed-grass (Hesperus) and sage brush/juniper (Molina) vegetation types. Vegetative structure differed between the sites with Molina having more cover provided by shrubs and Hesperus having more cover provided by forbs. Adult male deer mice moved greater distances at Hesperus than at Molina. Sub-adult males tended to move greater distances than did adult females. Relative abundances of deer mice tended to differ by season, but the average relative abundance of deer mice was greater at Molina. Long-term prevalence of infection with SNV was greater at Hesperus and was greatest in adult males at Hesperus (36.1%). Adult males at Molina exhibited a prevalence of infection with SNV of 25.0%. Infection with SNV was highly associated with scars or wounds for adult male, adult female, and juvenile male deer mice at Hesperus, but only for adult female deer mice at Molina. The presence of scars or wounds tended to be associated with greater age, but male deer mice at Hesperus were more likely to have wounds than female deer mice of the same age class. A similar pattern, excluding juveniles, was observed at Molina. Intraspecific interactions and environmentally elicited long-distance movements of deer mice may play a role in prevalence of infection with SNV in these animals.