Household risk of SARS-CoV-2 secondary infection

Both the scientific community and the general public have put considerable thought and effort towards avoiding covid-19 in public places, like grocery stores and airplanes. But perhaps the greatest risk actually comes at home. 

Health departments in Canada are reporting a spike in cases following Canadian Thanksgiving two weeks ago and a report published in the Center for Disease Control and Prevention's MMWR (Morbidity and Mortality Weekly Report) last week examined SARS-CoV-2 transmission in households. Researchers examined data from an ongoing CDC study of homes in Nashville and Marshfield, WI, between April-September. The average age of the first covid-19 patient in a household (known as "index patients") was 32 years; 14 percent were under age 18. Sixty-nine percent of the index patients reported spending greater than four hours in the same room with one or more household members the day before and 40 percent the day after illness onset. The median number of household members per bedroom was one, but index patients slept in the same room 40 percent of the time before illness onset and 30 percent after illness onset. These home exposures led to a "secondary infection rate" of 53 percent with a median onset of four days for symptom onset among household contacts. Seventy-five percent of secondary infections were identified within five days of the onset of symptoms in the index patients.

This study shows that in-home secondary infection is a serious risk to household members and that many aren't taking necessary precautions, such as isolating ill family members. It also indicates that both children and adults are at risk when other family members are infected. Finally, it provides evidence supporting the CDC's declaration on stays on residential evictions—which are known to force families into moving in with relatives, thereby increasing the number of people per household and placing more people at higher risk. 


Trump hints at firing Fauci

At a late night rally in Florida, President Trump suggested to the assembled crowd that he was considering removing Dr. Anthony Fauci, one of the nation's leading infectious diseases experts and member of the White House Coronavirus Task Force, from his position as the director of the National Institute of Allergy and Infectious Disease at the National Institutes of Health. The suggestion from the President came following chants from the audience to "Fire Fauci." Fauci has become more vocal regarding the mismanagement of the covid-19 pandemic in the United States despite the assertion from the Trump administration and Trump himself that covid-19 is under control and that the nation is "rounding the turn" of the pandemic.

It is worth noting that President Trump himself could not directly fire Dr. Fauci, who is a career civil servant, but could task the action to a political appointee if he so desired. Former Vice President Joseph R. Biden, Jr. addressed President Trump's comment at a rally on Monday afternoon, stating "If you think they've done a bad job at managing Covid so far, basically what they're telling you now is you ain't seen nothing yet." On Friday, the US posted an all-time high number of new infections at roughly 99,000 cases.

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