TY - JOUR T1 - Epidemiological comparison of the first and second waves of the COVID-19 pandemic in Nigeria, February 2020–April 2021 JF - BMJ Global Health JO - BMJ Global Health DO - 10.1136/bmjgh-2021-007076 VL - 6 IS - 11 SP - e007076 AU - Oluwatosin Wuraola Akande AU - Kelly Osezele Elimian AU - Ehimario Igumbor AU - Lauryn Dunkwu AU - Chijioke Kaduru AU - Olubunmi Omowunmi Olopha AU - Dabri Olohije Ohanu AU - Lilian Nwozor AU - Emmanuel Agogo AU - Olusola Aruna AU - Muhammad Shakir Balogun AU - Olaolu Aderinola AU - Anthony Ahumibe AU - Chinedu Arinze AU - Sikiru Olanrewaju Badaru AU - William Nwachukwu AU - Augustine Olajide Dada AU - Cyril Erameh AU - Khadeejah Hamza AU - Tarik Benjamin Mohammed AU - Nnaemeka Ndodo AU - Celestina Obiekea AU - Chinenye Ofoegbunam AU - Oladipo Ogunbode AU - Cornelius Ohonsi AU - Ekaete Alice Tobin AU - Rimamdeyati Yashe AU - Afolabi Adekaiyaoja AU - Michael C. Asuzu AU - Rosemary Ajuma Audu AU - Muhammad Bashir Bello AU - Shaibu Oricha Bello AU - Yusuf Yahaya Deeni AU - Yahya Disu AU - Gbenga Joseph AU - Chidiebere Ezeokafor AU - Zaiyad Garba Habib AU - Christian Ibeh AU - Ifeanyi Franklin Ike AU - Emem Iwara AU - Rejoice Kudirat Luka-Lawal AU - Geoffrey Namara AU - Tochi Okwor AU - Lois Olajide AU - Oluwafunke Olufemi Ilesanmi AU - Solomon Omonigho AU - Ferdinand Oyiri AU - Koubagnine Takpa AU - Nkem Usha Ugbogulu AU - Priscilla Ibekwe AU - John Oladejo AU - Elsie Ilori AU - Chinwe Lucia Ochu AU - Chikwe Ihekweazu Y1 - 2021/11/01 UR - http://gh.bmj.com/content/6/11/e007076.abstract N2 - 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.Data are available on reasonable request. Data may be made available on request, subject to compliance with the Nigeria Centre for Disease Control (NCDC) data sharing policy. ER -