Community Prevalence of SARS-CoV-2 Among Patients With Influenzalike Illnesses Presenting to a Los A

[Elderberry]

JAMA by Brad Spellberg, MD1; Meredith Haddix, MPH2; Rebecca Lee, MPH2; et al 3/31/2020

Community Prevalence of SARS-CoV-2 Among Patients With Influenzalike Illnesses Presenting to a Los Angeles Medical Center in March 2020

Until recently, diagnostic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), was only available through public health laboratories.1-3 This limited testing was prioritized for persons who had severe illness or identifiable risk factors, such as travel to an area with ongoing transmission. Thus, the incidence of community transmission by persons with mild illness and without risk factors remains ill-defined.

The current public health strategy of case containment is premised on the assumption of no or limited community transmission. Identifying a high rate of community transmission would indicate a need to shift the public health strategy from containment to mitigation of spread. Thus, determining the rate at which mild disease is spreading in the community, particularly among persons without risk factors for acquisition of the virus, is critically important.

We conducted a rapid sentinel surveillance study to determine what proportion of mild, outpatient influenzalike illnesses were caused by SARS-CoV-2.


Results

One hundred thirty-one tests for SARS-CoV-2 were obtained and 7 were positive (5.3%; 95% CI, 2.2%-10.7%). The median age of patients who tested positive was 38 years (range, 34-44 years), 3 were male (43%), and the median duration of symptoms was 4 days (range, 2-4 days) at presentation. Six of 7 patients presented with fever, 5 with myalgias, and only 1 with cough. Only 1 patient had a travel history (returned from Miami, Florida). All patients had mild illnesses, and all tested negative for influenza and respiratory syncytial virus.------

Discussion

The 5% rate of SARS-CoV-2 among patients with mild influenzalike illness without risk factors is concerning. These patients had sufficiently mild illness to be active in the community throughout their illness, increasing the possibility of transmission. Such transmission is consistent with the unusual, third countywide influenzalike illness spike that occurred late in the season and with declining rates of influenza positivity.

More: https://jamanetwork.com/journals/jama/fullarticle/2764137