The New England Journal, "Clinical Characteristics of Coronavirus Disease 2019 in China," dated February 28, 2019, posted on the internet yesterday, February 29, 2019. Link here.
Background:
- total number of patients studied: 1,099; laboratory-confirmed Covid-19
- 522 hospitals in 30 provinces, autonomous regions, and municipalities in China through January 29, 2020
- originally published in Chinese and then translated; authors: four Chinese for the China Medical Treatment Expert Group for Covid-19;
- only 1.9% (and that's how they phrased it, "only") of the patients had a history of direct contact with wildlife;
- among non-residents of Wuhan, 70% had contact with residents of Wuhan, including 30% who had visited the city;
- most common symptoms: fever and cough; but fever was seen in less than half of those patients at time of admission (or just prior to admission);
- diarrhea: uncommon
- median incubation period: 4 days;
- chest x-rays: "pretty much" diagnostic if present
- a decrease in lymphocytes was present in 80% of patients on admission to hospital
- patients often presented without fever and many did not have abnormal radiologic findings
- this is why this is called severe acute respiratory disease
- one does not generally get admitted to a hospital unless the condition is severe or contagious illness suspected;
- the chest x-ray findings/changes generally lag clinical presentation (true in almost any respiratory disease)
- so these patients were showing signs of fever and cough, but not necessarily severe respiratory distress; and x-rays were still clear;
- our study cannot preclude the presence of patients who have been termed "super-spreaders"
- despite the number of deaths associated with Covid-19, SARS-CoV-2 appears to have a lower case fatality rate than either SARS-CoV or Middle East respiratory-related coronavirus (MERS-CoV)
- fever and cough were the dominant symptoms [but] gastrointestinal symptoms were uncommon, which suggests a difference in viral tropism as compared with SARS-CoV [the "original SARS"], MERS-CoV, and seasonal influenza
- the absence of fever in Covid-19 is more frequent than in SARS-CoV (1%) and MERS-CoV infection (2%), so afebrile patients may be missed if the surveillance case definition focuses on fever detection;
- Our findings were more similar to the national official statistics, which showed a rate of death of 3.2% among 51,857 cases of Covid-19 as of February 16, 2020.
- Since patients who were mildly ill and who did not seek medical attention were not included in our study, the case fatality rate in a real-world scenario might be even lower.
- Early isolation, early diagnosis, and early management might have collectively contributed to the reduction in mortality in Guangdong.