Dynamic changes and the spread of epidemic from Wuhan city to Henan province On Jan 21st, the National Health Committee confirmed the first imported cases of pneumonia in Henan province (Figure 1A). On Feb 12nd, there were a total of 1169 cumulative cases and a peak value of 901 existing cases in the province (Figure 1B). It took 22 days to reach the peak of existing confirmed cases since the first confirmed case in Henan province. With the gradual decrease in the number of newly confirmed cases and the continuous increase in the number of cures, the cumulative number of cases in Henan province reached 1,272 as of Mar 10th, whereas excluding 22 deaths there is only 1 existing case (Figure 1C, D). We compared the outcomes of patients in Henan province, Wuhan City, China excluding Wuhan City, China, and worldwide excluding China on Mar 10th. We found the fatality rate of patients was lower in the regions outside of Wuhan than in Wuhan, while the cure rate of patients was higher in regions outside of Wuhan (Figure 1E, 1F). These results showed both present states and finial endings of COVID- 19 outside of Wuhan in Henan province would be better than that in Wuhan. Therefore, it can be learned from Henan about the experiences for controlling the spread of epidemics.
The correlation between outflow migration events and primary cases in Henan province.
Migration events are one of the most important factors associated with the spread of the epidemic. The closure of Wuhan on Jan 23rd, 2020 is the largest attempted movement restriction or quarantine in human history. To evaluate the influence of population movement before a closure of epidemic center of Wuhan on the spread of the COVID-19, we extracted a daily outflow index of Wuhan from Jan 10th (the start of the Lunar New Year travel rush) to Jan 23th 2020 (lockdown of major cities in Wuhan) from Baidu migration map. Our data showed a different proportion of the Wuhan-originated outflow population in 13 affected cities. For example, the outflow index of Xinyang is the highest among the cities, with a highest number of confirmed cases (Figure 2A). Next, we correlated the index of the 13 cities with the number of primary, or secondary, or totally confirmed cases in the compared city by using Spearman’s analysis. The results showed significant positive correlations between population input and the number of primary, or secondary, or totally confirmed cases. (Figure 2B, 2C, 2D; Spearman’s analysis, P<0.001)
Personal characteristics of 1272 patients with COVID-19 in Henan province
To investigate the outcomes and other epidemiolocal features in COVID-19 spread and control, publicly available data regarding confirmed cases from Health Committees of Henan province were extracted. As of Mar 10th, we tracked a total of 1272 cases, including information about age, sex, illness onset date, confirmed date et al. The details of 442 cured and 15 death patients were also analyzed in Table. Data showed that 45 (4.25%) of 1272 patients were aged 6 days-18 years, 475 (37.34%) were aged 18-40 years, 562 (44.18%) were aged 41 and 60 years, and 181 (14.23%) were aged 61 years and older. The median age was 44 years (interquartile range, 32-55 years). More than half of the 1272 patients (688, 54.09%) were male. In overall cases, 555 patients had travel or residence history of Wuhan in 2 weeks, including 2 patients who certainly contacted the Huanan seafood market. The credible information of 469 patients provides the exact date of leaving Wuhan, closely contacting with confirmed or suspected cases and illness onset. The median incubation period from leaving Wuhan or having contact history to symptoms was 7 (interquartile range, 4 to 10) days. Among 442 patients with exact datesof discharge, the median duration from illness onset to cure was 19 (interquartile range, 15 to 23) days. Among 15 patients with exact date of both illness onset and death, the mean interval from illness onset to death was 10 (interquartile range, 8 to 18) days, and their median age is 74 (interquartile range, 68-80) years.
Table. Epidemiological and demographical characteristics with clinical outcomes of COVID-19 patients in Henan province, China.
Patient (n=1272)
|
Age (years) (IQR)
|
44 (32-55)
|
Age groups(years) (n and %)
|
|
0-18
|
54 (4.25%)
|
19-40
|
475 (37.34%)
|
41-60
|
562 (44.18%)
|
61-98
|
181 (14.23%)
|
Sex (n) (%)
|
|
Male
|
688 (54.09%)
|
Female
|
584 (45.91%)
|
Exposure history in Wuhan (n) (%)
|
|
Yes
|
554(43.55%)
|
Huanan Seafood market in Wuhan
|
2 (0.16%)
|
No
|
718 (56.45%)
|
Incubation period (days) (IQR and n)
|
7(4-10)(469*)
|
Duration time of disease (days) (IQR and n)
|
19(15-23)(442*)
|
Time from illness onset to seeking care at a hospital (days) (IQR and n)
|
2(0-5)(442*)
|
Time from seeking care at a hospital to cure (days) (IQR
and n)
|
15(13-19)(442*)
|
Age of deaths (years) (IQR and n)
|
74(68-80)(15*)
|
Time from illness onset to death(days)(IQR)
|
10(8-18)(15*)
|
Values are medians (interquartile ranges, IQR) or counts (percentages, %). Numbers*(n) do not total 100% owing to inclusion and exclusion criteria or missing data.
Age distribution with classified patient into primary or secondary cases of the COVID-19 epidemic
We performed an extensive analysis of the age distribution of patients according to classifying primary or secondary cases in the spread of COVID-19. We found nearly 90% (497/555) primary cases are 19-60 years old patients. On admission, our results showed different proportions of secondary cases in different age groups (Figure 3A; Chi-square test, P<0.001), especially more than 3-fold of secondary cases to primary cases in elderly patients (>60 years old). Next, we further investigated the contact history in secondary cases of elderly patients, and the proportions of contact with primary cases was similar to secondary cases. Surprisingly, 27.14% of elderly patients became infected after contact their children or relatives who returned from Wuhan but not confirmed COVID-19 according to the reports (Figure 3B).
The duration and outcomes of the disease progression in different hospitals
Studies so far have not systematically analyzed the duration of cured patients. Here we showed the time from illness onset to seeking care at a hospital varies among people in different age groups (Figure 4A; Kruskal–Wallis test, P<0.01). The patients aged 61 years and older spent a median of 4 days from illness onset to seeking care at a hospital. We also showed the cure time varies among people in different age groups (Figure 4B, Kruskal–Wallis test, P<0.01). The patients younger than 19 years spent a median of 14 days from seeking care at a hospital to cure. Next, we analyzed the duration of COVID-19 in primary and secondary cases. The results showed that the difference between the two groups was mainly reflected in the duration from illness onset to seeking care at a hospital (Figure 4C; Mann-Whitney test t, P<0.05), while the time from seeking care at a hospital to cure was almost indifferent between two groups (Figure 4D; Mann-Whitney test t, P>0.05)).Besides, we found there is a significant cure of cure time of patients cured and discharged from city and several county hospitals in Xinyang (Figure 4E; Kruskal–Wallis test, P<0.001). Our results indicate that the medical environment is also one of the most important factors that affects the outcomes of COVID-19 patients.