# A Trendline and Predictive Analysis of the First-Wave COVID-19 Infections in Malta

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## Abstract

**:**

## 1. Introduction

## 2. Methodologies

#### 2.1. Trendline Analysis

#### 2.1.1. Data Collection

#### 2.1.2. Trendline Functions

#### 2.2. Predictive Analysis

## 3. Results

#### 3.1. Trendline Analysis

#### 3.1.1. Positive Infected-Case Function

^{2}) of 0.860 and 0.998, respectively. The functions were graphically superimposed upon the dataset, as illustrated in Figure 1.

#### 3.1.2. Swab-Test Function

#### 3.2. Predictive Analysis

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## Appendix A

## References

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**Figure 3.**Comparison between the derived trendline fit (Equation (10)) and the 5-day average, together with the intervention enforcement/relaxation dates.

- (
**A**) **Lockdown Measures**
| Enforcement Date | Relaxation Date |

International travel ban | 21 March 2020 | 1 July 2020 |

Lockdown of vulnerable persons | 28 March 2020 | 5 June 2020 |

National travel ban (essential travel only between the Maltese islands) | 3 April 2020 | 4 May 2020 |

- (
**B**) **Social Distancing Measures**
| Enforcement Date | Relaxation Date |

Public transport measures (daily decontamination; passenger screening; standing passengers disallowed; windows open; air-conditioning system off; no monetary change) | 12 March 2020 | 4 May 2020 |

Closure of workplaces and distancing of workers | 13 March 2020 | 5 June 2020 |

Closure of sports facilities | 13 March 2020 | 5 June 2020 |

Closure of law courts and local tribunals | 13 March 2020 | 5 June 2020 |

Closure of religious places | 13 March 2020 | 13 June 2020 |

Closure of service outlets and public places | 16 March 2020 | 22 May 2020 |

Closure of education establishments | 21 March 2020 | 5 June 2020 |

Closure of non-essential retail outlets | 23 March 2020 | 4 May 2020 |

Closure of non-essential service outlets | 23 March 2020 | 22 May 2020 |

Measures to protect elderly and high-risk groups | 28 March 2020 | 5 June 2020 |

Prohibition of public gatherings (limits of 3 persons, 4 persons, and 6 persons) | 30 March 2020 | 4 May 2020, 22 May 2020, 5 June 2020 |

Suspension of visits to homes for the elderly and the national hospital | 8 April 2020 | 25 May 2020 |

Equation | ${\mathit{M}}_{\mathit{c}1}$ | ${\mathit{\lambda}}_{\mathit{c}1}$ | ${\mathit{k}}_{\mathit{c}1}$ | ${\mathit{M}}_{\mathit{c}2}$ | ${\mathit{\lambda}}_{\mathit{c}2}$ | ${\mathit{k}}_{\mathit{c}2}$ | ${\mathit{M}}_{\mathit{c}3}$ | ${\mathit{\lambda}}_{\mathit{c}3}$ | ${\mathit{k}}_{\mathit{c}3}$ | ${\mathit{R}}^{2}$ |
---|---|---|---|---|---|---|---|---|---|---|

Equation (1) | 6.486 | - | - | - | - | - | - | - | - | 0.806 |

95% CI | 6.677 | - | - | - | - | - | - | - | - | |

6.296 | ||||||||||

Equation (2) | 885.6 | 78.32 | - | - | - | - | - | - | - | 0.970 |

95% CI | 940.3 | 87.12 | - | - | - | - | - | - | - | |

830.9 | 69.53 | |||||||||

Equation (3) | 680.0 | 49.61 | 1.581 | - | - | - | - | - | - | 0.991 |

95% CI | 691.2 | 51.01 | 1.655 | - | - | - | - | - | - | |

668.9 | 48.21 | 1.508 | ||||||||

Equation (4) | 434.8 | 31.38 | 2.628 | 234.3 | 79.05 | 4.687 | - | - | - | 0.996 |

95% CI | 472.0 | 33.12 | 2.836 | 273.8 | 82.32 | 5.888 | - | - | - | |

397.6 | 29.64 | 2.419 | 194.7 | 75.78 | 3.486 | |||||

Equation (5) | 484.6 | 33.64 | 2.486 | 64.03 | 100.2 | 12.25 | 123.4 | 73.59 | 17.98 | 0.998 |

95% CI | 495.6 | 34.41 | 2.606 | 82.83 | 103.7 | 20.26 | 145.1 | 74.73 | 23.93 | |

473.6 | 32.86 | 2.367 | 45.23 | 96.69 | 4.327 | 101.7 | 72.45 | 12.03 |

${\mathit{M}}_{\mathit{c}1}$ | ${\mathit{\lambda}}_{\mathit{c}1}$ | ${\mathit{k}}_{\mathit{c}1}$ | ${\mathit{M}}_{\mathit{c}2}$ | ${\mathit{\lambda}}_{\mathit{c}2}$ | ${\mathit{k}}_{\mathit{c}2}$ | ${\mathit{M}}_{\mathit{c}3}$ | ${\mathit{\lambda}}_{\mathit{c}3}$ | ${\mathit{k}}_{\mathit{c}3}$ | ${\mathit{R}}^{2}$ | |
---|---|---|---|---|---|---|---|---|---|---|

Equation (6) | 4.542 | - | - | - | - | - | - | - | - | 0.0 |

95% CI | 5.427 | - | - | - | - | - | - | - | - | |

3.657 | ||||||||||

Equation (7) | 818.4 | 93.88 | - | - | - | - | - | - | - | 0.183 |

95% CI | 1077 | 137.1 | - | - | - | - | - | - | - | |

560.0 | 50.71 | |||||||||

Equation (8) | 618.8 | 50.32 | 1.568 | - | - | - | - | - | - | 0.376 |

95% CI | 716.3 | 57.79 | 1.809 | - | - | - | - | - | - | |

521.3 | 42.84 | 1.327 | ||||||||

Equation (9) | 371.1 | 30.77 | 2.357 | 222.4 | 76.42 | 5.118 | - | - | - | 0.459 |

95% CI | 476.9 | 36.07 | 2.836 | 273.8 | 82.32 | 5.888 | - | - | - | |

265.3 | 29.64 | 2.419 | 194.7 | 75.78 | 3.486 | |||||

Equation (10) | 429.6 | 33.94 | 2.168 | 51.61 | 99.86 | 18.60 | 124.8 | 74.35 | 17.37 | 0.556 |

95% CI | 495.6 | 34.41 | 2.606 | 82.83 | 103.7 | 20.26 | 145.1 | 74.73 | 23.93 | |

473.6 | 32.86 | 2.367 | 45.23 | 96.69 | 4.327 | 101.7 | 72.45 | 12.03 |

${\mathit{M}}_{\mathit{s}1}$ | ${\mathit{\lambda}}_{\mathit{s}1}$ | ${\mathit{k}}_{\mathit{s}1}$ | ${\mathit{R}}^{2}$ | |
---|---|---|---|---|

Equation (11) | 673.0 | - | - | 0.901 |

95% CI | 650.1 | - | - | |

695.9 | ||||

Equation (12) | 118,770.3 | 104.9 | 2.652 | 0.999 |

95% CI | 117,054.6 | 103.7 | 2.612 | |

120,486.0 | 106.1 | 2.692 |

${\mathit{M}}_{\mathit{s}1}$ | ${\mathit{\lambda}}_{\mathit{s}1}$ | ${\mathit{k}}_{\mathit{s}1}$ | ${\mathit{R}}^{2}$ | |
---|---|---|---|---|

Equation (13) | 749.8 | - | - | 0.0 |

95% CI | 678.8 | - | - | |

820.9 | ||||

Equation (14) | 127,657.8 | 110.0 | 2.499 | 0.762 |

95% CI | 118,635.2 | 105.2 | 2.317 | |

136,680.4 | 114.8 | 2.681 |

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**MDPI and ACS Style**

Borg, M.G.; Borg, M.A.
A Trendline and Predictive Analysis of the First-Wave COVID-19 Infections in Malta. *Epidemiologia* **2023**, *4*, 33-50.
https://doi.org/10.3390/epidemiologia4010003

**AMA Style**

Borg MG, Borg MA.
A Trendline and Predictive Analysis of the First-Wave COVID-19 Infections in Malta. *Epidemiologia*. 2023; 4(1):33-50.
https://doi.org/10.3390/epidemiologia4010003

**Chicago/Turabian Style**

Borg, Mitchell G., and Michael A. Borg.
2023. "A Trendline and Predictive Analysis of the First-Wave COVID-19 Infections in Malta" *Epidemiologia* 4, no. 1: 33-50.
https://doi.org/10.3390/epidemiologia4010003