Epidemiological comparison of the first and second waves of the COVID-19 pandemic in Nigeria, February 2020-April 2021.
COVID-19
descriptive study
epidemiology
Journal
BMJ global health
ISSN: 2059-7908
Titre abrégé: BMJ Glob Health
Pays: England
ID NLM: 101685275
Informations de publication
Date de publication:
11 2021
11 2021
Historique:
received:
03
08
2021
accepted:
24
10
2021
entrez:
19
11
2021
pubmed:
20
11
2021
medline:
24
11
2021
Statut:
ppublish
Résumé
With reports of surges in COVID-19 case numbers across over 50 countries, country-level epidemiological analysis is required to inform context-appropriate response strategies for containment and mitigation of the outbreak. We aimed to compare the epidemiological features of the first and second waves of COVID-19 in Nigeria. We conducted a retrospective analysis of the Surveillance Outbreak Response Management and Analysis System data of the first and second epidemiological waves, which were between 27 February and 24 October 2020, and 25 October 2020 to 3 April 2021, respectively. Descriptive statistical measures including frequencies and percentages, test positivity rate (TPR), cumulative incidence (CI) and case fatality rates (CFRs) were compared. A p value of <0.05 was considered statistically significant. All statistical analyses were carried out in STATA V.13. There were 802 143 tests recorded during the study period (362 550 and 439 593 in the first and second waves, respectively). Of these, 66 121 (18.2%) and 91 644 (20.8%) tested positive in the first and second waves, respectively. There was a 21.3% increase in the number of tests conducted in the second wave with TPR increasing by 14.3%. CI during the first and second waves were 30.3/100 000 and 42.0/100 000 respectively. During the second wave, confirmed COVID-19 cases increased among females and people 30 years old or younger and decreased among urban residents and individuals with travel history within 14 days of sample collection (p value <0.001). Most confirmed cases were asymptomatic at diagnosis during both waves: 74.9% in the first wave; 79.7% in the second wave. CFR decreased during the second wave (0.7%) compared with the first wave (1.8%). Nigeria experienced a larger but less severe second wave of COVID-19. Continued implementation of public health and social measures is needed to mitigate the resurgence of another wave.
Sections du résumé
BACKGROUND
With reports of surges in COVID-19 case numbers across over 50 countries, country-level epidemiological analysis is required to inform context-appropriate response strategies for containment and mitigation of the outbreak. We aimed to compare the epidemiological features of the first and second waves of COVID-19 in Nigeria.
METHODS
We conducted a retrospective analysis of the Surveillance Outbreak Response Management and Analysis System data of the first and second epidemiological waves, which were between 27 February and 24 October 2020, and 25 October 2020 to 3 April 2021, respectively. Descriptive statistical measures including frequencies and percentages, test positivity rate (TPR), cumulative incidence (CI) and case fatality rates (CFRs) were compared. A p value of <0.05 was considered statistically significant. All statistical analyses were carried out in STATA V.13.
RESULTS
There were 802 143 tests recorded during the study period (362 550 and 439 593 in the first and second waves, respectively). Of these, 66 121 (18.2%) and 91 644 (20.8%) tested positive in the first and second waves, respectively. There was a 21.3% increase in the number of tests conducted in the second wave with TPR increasing by 14.3%. CI during the first and second waves were 30.3/100 000 and 42.0/100 000 respectively. During the second wave, confirmed COVID-19 cases increased among females and people 30 years old or younger and decreased among urban residents and individuals with travel history within 14 days of sample collection (p value <0.001). Most confirmed cases were asymptomatic at diagnosis during both waves: 74.9% in the first wave; 79.7% in the second wave. CFR decreased during the second wave (0.7%) compared with the first wave (1.8%).
CONCLUSION
Nigeria experienced a larger but less severe second wave of COVID-19. Continued implementation of public health and social measures is needed to mitigate the resurgence of another wave.
Identifiants
pubmed: 34794956
pii: bmjgh-2021-007076
doi: 10.1136/bmjgh-2021-007076
pmc: PMC8602923
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : World Health Organization
ID : 001
Pays : International
Informations de copyright
© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
Déclaration de conflit d'intérêts
Competing interests: None declared.
Références
Lancet Infect Dis. 2021 Jul;21(7):922-923
pubmed: 34174236
Am J Trop Med Hyg. 2020 Dec;103(6):2376-2381
pubmed: 33124545
Int J Infect Dis. 2021 Mar;104:742-745
pubmed: 33556610
Pan Afr Med J. 2020 Dec 15;37(Suppl 1):47
pubmed: 33552375
J Infect. 2021 Apr;82(4):84-123
pubmed: 33152376
Int J Infect Dis. 2021 Apr;105:374-376
pubmed: 33684560
Health Secur. 2021 Mar-Apr;19(2):223-228
pubmed: 33346721
Lancet. 2021 Apr 3;397(10281):1265-1275
pubmed: 33773118
BMJ Open. 2020 Dec 17;10(12):e044079
pubmed: 33334842
J Infect. 2021 Jun;82(6):e14-e15
pubmed: 33826927
Am J Trop Med Hyg. 2021 Jan 20;104(3):1034-1040
pubmed: 33534753
BMJ. 2020 Aug 27;370:m3350
pubmed: 32855153
Proc Natl Acad Sci U S A. 2020 Nov 3;117(44):27285-27291
pubmed: 33060298
Epidemiol Infect. 2020 Sep 11;148:e208
pubmed: 32912370
PLoS One. 2021 Mar 15;16(3):e0248281
pubmed: 33720975
BMJ Glob Health. 2021 Mar;6(3):
pubmed: 33741561
Chaos. 2021 Mar;31(3):031105
pubmed: 33810707
Acta Biomed. 2020 Mar 19;91(1):157-160
pubmed: 32191675
CMAJ. 2012 Aug 7;184(11):1265-9
pubmed: 22371511
BMC Public Health. 2020 Nov 19;20(1):1742
pubmed: 33213391
J Glob Health. 2020 Dec;10(2):020399
pubmed: 33274062