Sin Nombre Virus
Incubation
Sin Nombre virus causes hantavirus pulmonary syndrome after a two to three week incubation period.
Epidemiology
The reservoir for Sin Nombre virus is deer mice, which are present throughout western and central United States and parts of Canada. Cases of HPS have been found in 30 states and four provinces of Canada. The seroprevalence of Sin Nombre is relatively low, at only 0.2% of the general population. Outbreaks typically appear in clusters and are associated with sudden increases in deer mice populations, such as in the first known outbreak in the Four Corners region. These outbreaks occur in the late spring or early summer.
Original image from www.cdc.gov
Symptomatology and Outcome
The first phase of HPS is a rapid onset febrile illness, with influenza-like symptoms. This includes myalgia, malaise and headache. This is followed by more serious symptoms of pulmonary edema, dyspnea and hypoxemia. At this point the patient is often admitted to a hospital, and lung infiltrates can be detected on chest radiographs. The patient can go into shock and there is an almost 50% mortality rate within one to three days of hospital admission. Patients who survive the critical phase of HPS recover quickly over a period of three to six days.
Prevention and Management
Prevention is focused mainly on control of deer mice populations and sanitation measures. Aspects of this include proper food storage methods, preventing rodent access to homes, and the removal of rodents and rodent droppings. There is no person-to-person transmission so the disease is relatively easy to contain.