PLOS Global Public Health (Jan 2022)

COVID-19 mortality rate and its associated factors during the first and second waves in Nigeria.

  • Kelly Elimian,
  • Anwar Musah,
  • Carina King,
  • Ehimario Igumbor,
  • Puja Myles,
  • Olaolu Aderinola,
  • Cyril Erameh,
  • William Nwanchukwu,
  • Oluwatosin Akande,
  • Ndembi Nicaise,
  • Oladipo Ogunbode,
  • Abiodun Egwuenu,
  • Emily Crawford,
  • Giulia Gaudenzi,
  • Ismail Abdus-Salam,
  • Olubunmi Olopha,
  • Yahya Disu,
  • Abimbola Bowale,
  • Cyprian Oshoma,
  • Cornelius Ohonsi,
  • Chinedu Arinze,
  • Sikiru Badaru,
  • Blessing Ebhodaghe,
  • Zaiyad Habib,
  • Michael Olugbile,
  • Chioma Dan-Nwafor,
  • Jafiya Abubakar,
  • Emmanuel Pembi,
  • Lauryn Dunkwu,
  • Ifeanyi Ike,
  • Ekaete Tobin,
  • Bamidele Mutiu,
  • Rejoice Luka-Lawal,
  • Obinna Nwafor,
  • Mildred Okowa,
  • Chidiebere Ezeokafor,
  • Emem Iwara,
  • Sebastian Yennan,
  • Sunday Eziechina,
  • David Olatunji,
  • Lanre Falodun,
  • Emmanuel Joseph,
  • Ifeanyi Abali,
  • Tarik Mohammed,
  • Benjamin Yiga,
  • Khadeejah Kamaldeen,
  • Emmanuel Agogo,
  • Nwando Mba,
  • John Oladejo,
  • Elsie Ilori,
  • Olusola Aruna,
  • Geoffrey Namara,
  • Stephen Obaro,
  • Khadeejah Hamza,
  • Michael Asuzu,
  • Shaibu Bello,
  • Friday Okonofua,
  • Yusuf Deeni,
  • Ibrahim Abubakar,
  • Tobias Alfven,
  • Chinwe Ochu,
  • Chikwe Ihekweazu

DOI
https://doi.org/10.1371/journal.pgph.0000169
Journal volume & issue
Vol. 2, no. 6
p. e0000169

Abstract

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COVID-19 mortality rate has not been formally assessed in Nigeria. Thus, we aimed to address this gap and identify associated mortality risk factors during the first and second waves in Nigeria. This was a retrospective analysis of national surveillance data from all 37 States in Nigeria between February 27, 2020, and April 3, 2021. The outcome variable was mortality amongst persons who tested positive for SARS-CoV-2 by Reverse-Transcriptase Polymerase Chain Reaction. Incidence rates of COVID-19 mortality was calculated by dividing the number of deaths by total person-time (in days) contributed by the entire study population and presented per 100,000 person-days with 95% Confidence Intervals (95% CI). Adjusted negative binomial regression was used to identify factors associated with COVID-19 mortality. Findings are presented as adjusted Incidence Rate Ratios (aIRR) with 95% CI. The first wave included 65,790 COVID-19 patients, of whom 994 (1∙51%) died; the second wave included 91,089 patients, of whom 513 (0∙56%) died. The incidence rate of COVID-19 mortality was higher in the first wave [54∙25 (95% CI: 50∙98-57∙73)] than in the second wave [19∙19 (17∙60-20∙93)]. Factors independently associated with increased risk of COVID-19 mortality in both waves were: age ≥45 years, male gender [first wave aIRR 1∙65 (1∙35-2∙02) and second wave 1∙52 (1∙11-2∙06)], being symptomatic [aIRR 3∙17 (2∙59-3∙89) and 3∙04 (2∙20-4∙21)], and being hospitalised [aIRR 4∙19 (3∙26-5∙39) and 7∙84 (4∙90-12∙54)]. Relative to South-West, residency in the South-South and North-West was associated with an increased risk of COVID-19 mortality in both waves. In conclusion, the rate of COVID-19 mortality in Nigeria was higher in the first wave than in the second wave, suggesting an improvement in public health response and clinical care in the second wave. However, this needs to be interpreted with caution given the inherent limitations of the country's surveillance system during the study.