Descriptive Analysis
As of 2nd April 2020, a total of 110 COVID 19 confirmed cases had been reported in Kenya. In addition, three mortality cases and four recoveries had also been reported in the same duration. Figure 4 presents the cumulative confirmed COVID 19 cases in Kenya in the first 21 days.
Table 1 presents the number of daily new cases reported, the cumulative cases and the percentage change in new cases compared with the previous day. The average percentage daily change in the period under consideration was 32%, with the least change being 0% and the highest change being 200%. The highest number of new daily-confirmed cases was in Day 21 when 29 cases were reported. Worth to note is that Day 20 and 21 recorded over 20 new confirmed cases apiece and this could be attributed to the massive testing of individuals specifically those under the mandatory quarantine. Further analysis indicated that a total of 51 cases were confirmed on day 20 and 21, and out of these, 44 were in the mandatory quarantine centers representing 86% of new cases confirmed in both days.
Table 1: Daily and Cumulative COVID-19 Cases in Kenya
Date
|
Cumulative Number of Cases
|
Number of New Cases
|
% Change from Previous Day
|
Day 1
|
1
|
1
|
-
|
Day 2
|
1
|
0
|
0%
|
Day 3
|
3
|
2
|
200%
|
Day 4
|
3
|
0
|
0%
|
Day 5
|
4
|
1
|
33%
|
Day 6
|
7
|
3
|
75%
|
Day 7
|
7
|
0
|
0%
|
Day 8
|
7
|
0
|
0%
|
Day 9
|
7
|
0
|
0%
|
Day 10
|
15
|
8
|
114%
|
Day 11
|
16
|
1
|
7%
|
Day 12
|
25
|
9
|
56%
|
Day 13
|
28
|
3
|
12%
|
Day 14
|
31
|
3
|
11%
|
Day 15
|
31
|
0
|
0%
|
Day 16
|
38
|
7
|
23%
|
Day 17
|
42
|
4
|
11%
|
Day 18
|
50
|
8
|
19%
|
Day 19
|
59
|
9
|
18%
|
Day 20
|
81
|
22
|
37%
|
Day 21
|
110
|
29
|
36%
|
Case Fatality Rate
The Case Fatality Rate (CFR) in Kenya on COVID-19 as of day 21 is estimated as 2.7% ranging between 3.2% in Day 14 when the 1st mortality case was recorded to 1.2% in Day 20. The CFR has been on a downward trend from Day 14 to Day 20, but picked in Day 21 (Figure 5).
Additionally, the CFR on closed cases (cases with an outcome) was calculated for Day 21 and recorded as 42.9% ranging from 50% in Day 14 to 25% in Day 20.
Projection of COVID 19 Cases in Kenya
The parameters of interest were estimated using a linear and non-linear exponential model (equation 1) and the parameters of interest are presented in Table 2 and 3 respectively.
Table 2: Estimated Exponential Model Parameters for Kenya (Linear Model)
Table 3: Estimated Exponential Model Parameters for Kenya (Non-Linear Model)
The graphical presentation of both models against the actual number of reported in Kenya in the 21 days span is presented in Figure 6. As evidenced in Figure 6, there was a near perfection in estimation of cases by both models until day 16, when the linear model started to overestimate the cases. On the other hand, the non-linear model seems better in estimating the cases.
Figure 7 presents the trends in projected cases of COVID-19 in Kenya for 40 days since the 1st case was recorded. The presentation is based on the non-linear exponential growth model. According to the model, there will be sharp acceleration of confirmed cases from Day 32 (13th April 2020) until the end of the projection period.
Using the non-linear model, Kenya will record 1,000 confirmed cased of COVID-19 on 14th April 2020, and 4,000 confirmed COVID 19 cases on 21st April 2020. On the other hand, using the linear model, then 1,000 COVID-19 cases will be reached on 12th April and 4,000 cases will be reached on 19th April 2020. The daily predicted COVID-19 cumulative cases are presented in Table 4.
Table 4: Projected Daily Cumulative COVID-19 Cases in Kenya
Date
|
Reported Cases (Actual)
|
Linear Estimation
|
Non-Linear Estimation
|
13th Mar
|
1
|
2
|
2
|
14th Mar
|
1
|
2
|
3
|
15th Mar
|
3
|
2
|
3
|
16th Mar
|
3
|
3
|
4
|
17th Mar
|
4
|
4
|
5
|
18th Mar
|
7
|
5
|
5
|
19th Mar
|
7
|
6
|
7
|
20th Mar
|
7
|
7
|
8
|
21st Mar
|
7
|
9
|
10
|
22nd Mar
|
15
|
11
|
12
|
23rd Mar
|
16
|
14
|
14
|
24th Mar
|
25
|
17
|
18
|
25th Mar
|
28
|
21
|
21
|
26th Mar
|
31
|
26
|
26
|
27th Mar
|
31
|
32
|
31
|
28th Mar
|
38
|
40
|
38
|
29th Mar
|
42
|
50
|
46
|
30th Mar
|
50
|
61
|
56
|
31st Mar
|
59
|
76
|
68
|
1st Apr
|
81
|
95
|
83
|
2nd Apr
|
110
|
117
|
100
|
3rd Apr
|
122
|
146
|
122
|
4th Apr
|
|
181
|
148
|
5th Apr
|
|
225
|
180
|
6th Apr
|
|
279
|
218
|
7th Apr
|
|
346
|
265
|
8th Apr
|
|
429
|
322
|
9th Apr
|
|
533
|
390
|
10th Apr
|
|
662
|
474
|
11th Apr
|
|
821
|
575
|
12th Apr
|
|
1,019
|
699
|
13th Apr
|
|
1,265
|
848
|
14th Apr
|
|
1,570
|
1,030
|
15th Apr
|
|
1,949
|
1,250
|
16th Apr
|
|
2,418
|
1,518
|
17th Apr
|
|
3,002
|
1,843
|
18th Apr
|
|
3,725
|
2,238
|
19th Apr
|
|
4,624
|
2,717
|
20th Apr
|
|
5,739
|
3,298
|
21st Apr
|
|
7,123
|
4,004
|