A new paper released by the Chinese Centers for Disease Control and Prevention (CCDC) reports that most cases of coronavirus are moderate, with older adults and people with other illnesses being at greatest risk.
A study was conducted by CCDC’s Novel Coronavirus Pneumonia Emergency Response Epidemiology Group to examine all confirmed cases of coronavirus as of February 11, 2020.
The novel coronavirus SARS-CoV-2 has just been identified by experts. The disease that induces virus infection is called COVID-19.
The CCDC group in the new study gathered all of the COVID-19 cases reported by China’s Infectious Disease Information System.
The scientists had included the following in their analysis:
- a “summary of patient characteristics”
- an analysis of viral spread by age and sex
- a calculation of deaths and the “case fatality rate”
- an analysis of viral spread over time and geographical space
- an epidemiological curve, or visual display of the outbreak
- a subgroup analysis of cases outside of China’s Hubei Province and “all cases among health workers nationwide”
The findings appear in the journal CCDC Weekly.
80.9% of the cases are ‘mild’
The researchers analyzed a total of 72,314 patient records, which included: “44,672 (61.8%) confirmed cases, 16,186 (22.4%) suspected cases, 10,567 (14.6%) clinically diagnosed cases,” and “889 asymptomatic cases (1.2%).”
Of the overall number of confirmed cases, 80.9% were said to be “mild.” Most of the affected individuals were between 30 and 799%.
Of the total number of confirmed cases, 1,023 fatalities were recorded, the equivalent of 2.3 per cent death rate. To men, the virus proved more lethal— 2.8%— than for women— 1.7%.
Less deadly than SARS
Importantly, the study found the risk of fatality in the case increases with age. Approximately, up to the age of 39, the fatality rate is 0.2%, at the age of 40, 0.4%, 1.3% for those in their fifties, 3.6% for those in their sixties, and eventually 8% for those in their seventies.
In comparison, according to the World Health Organization (WHO), the Severe Acute Respiratory Syndrome (SARS) that health experts compared coronavirus to less affected people in 2002–2003, but the death rate was 14–15 percent.
With regard to the geotemporal spread of the virus, the study confirms that “COVID-19 spread out from the province of Hubei sometime after December 2019, and by February 11, 2020, 1,386 counties across all 31 provinces were affected.”
The study also found that people with cardiovascular disease were at the highest risk of coronavirus death, followed by those with diabetes, chronic respiratory disease.
In addition, the authors note a “trend in the general disease curve downward.”
The outbreak curve shows that the onset of symptoms “peaked around 23–26 January, then started to decline, leading to 11 February,” they report.
They add that this indicates “that perhaps isolating entire communities, transmitting critical information (e.g. encouraging handwashing, mask wearing, and finding care) at high frequency across multiple channels, and mobilizing[ a] multi-sector rapid response teams helps curb the outbreak.”
Nevertheless, the authors note that an epidemic “rebound” is still very possible:
“[The] COVID-19 epidemic has spread very quickly, taking only 30 days to expand from Hubei to the rest of Mainland China. With many people returning from a long holiday, China needs to prepare for the possible rebound of the epidemic.”
The study also found that “a total of 1,716 health workers were infected and 5 died (0.3 percent).”
Nevertheless, “the number of serious cases among Wuhan medical staff gradually decreased from 38.9 percent at peak (on January 28) to 12.7 percent at the beginning of February.”