New Exposure Location for Hantavirus Pulmonary Syndrome Case

California, USA, 2018

Anne M. Kjemtrup; Sharon Messenger; Amy M. Meza; Tina Feiszli; Melissa Hardstone Yoshimizu; Kerry Padgett; Sunita Singh


Emerging Infectious Diseases. 2019;25(10):1962-1964. 

In This Article

Abstract and Introduction


We describe a case of hantavirus pulmonary syndrome in a patient exposed to Sin Nombre virus in a coastal county in California, USA, that had no previous record of human cases. Environmental evaluation coupled with genotypic analysis of virus isolates from the case-patient and locally trapped rodents identified the likely exposure location.


Hantavirus pulmonary syndrome (HPS), which is caused by infection with Sin Nombre virus (SNV), was made nationally notifiable in the United States in 1995. Since then, 71 cases in California residents have been reported (range 0–8 cases/y).[1] Persons are usually exposed to SNV through inhalation of aerosolized excreta (e.g., saliva, urine, and feces) from infected rodents, typically deer mice (Peromyscus maniculatus),[2] although other wild mice, such as the cactus mouse (P. eremicus), have been implicated as reservoirs in California.[3] SNV has been documented in deer mice throughout California,[4] but exposure for most human cases has been in noncoastal, mountainous (>900 m elevation), rural areas of the state.

Disease onset occurs after a 2–8-week incubation;[5] onset for 70% of California cases has occurred during May–September. Laboratory confirmation includes serologic testing (e.g., ELISA, IgM, and IgG), reverse transcription PCR (RT-PCR) testing of serum or respiratory samples, or immunohistochemistry to identify virus antigen in tissue.[5] Sequencing of viral RNA (most commonly glycoprotein or nucleoprotein open reading frames) is used to infer relationships of hantavirus strains from humans and rodents.[3,6] We report a case of HPS in a patient exposed to SNV in a coastal county in California, USA, that had no previous record of human cases.