Impact of COVID-19 on mortality in coastal Kenya: a longitudinal open cohort study (preprint)

Background: There is uncertainty about the mortality impact of the COVID-19 pandemic in Africa because of poor ascertainment of cases and limited national civil vital registration. We analysed excess mortality from 1st January 2020-5th May 2022 in a Health and Demographic Surveillance Study in Coastal Kenya where the SARS-CoV-2 seroprevalence reached 75% among adults in March 2022 despite vaccine uptake of only 17%. Methods: We modelled expected mortality in 2020-2022 among a population of 306,000 from baseline surveillance data between 2010-2019. We calculated excess mortality as the ratio of observed/expected deaths in 5 age strata for each month and for each national wave of the pandemic. We estimated cumulative mortality risks as the total number of excess deaths in the pandemic per 100,000 population. We investigated observed deaths using verbal autopsy. Findings: We observed 16,236 deaths among 3,410,800 person years between 1st January 2010 and 5th May 2022. Across 5 waves of COVID-19 cases during 1st April 2020-16th April 2022, population excess mortality was 4.1% (95% PI -0.2%, 7.9%). Mortality was elevated among those aged [≥]65 years at 14.3% (95% PI 7.4%, 21.6%); excess deaths coincided with wave 2 (wild-type), wave 4 (Delta) and wave 5 (Omicron BA1). Among children aged 1-14 years there was negative excess mortality of -20.3% (95% PI -29.8%, -8.1%). Verbal autopsy data showed a transient reduction in deaths from acute respiratory infections in 2020 at all ages. For comparison with other studies, cumulative excess mortality risk for January 2020-December 2021, age-standardized to the Kenyan population, was 47.5/100,000. Interpretation: Net excess mortality during the pandemic was substantially lower in Coastal Kenya than in many high income countries. However, adults, aged [≥]65 years, experienced substantial excess mortality suggesting that targeted COVID-19 vaccination of older persons may limit further COVID-19 deaths by protecting the residual pool of naive individuals.

Impact of the COVID-19 epidemic on mortality in rural coastal Kenya (preprint)

Background: The impact of COVID-19 on all-cause mortality in sub-Saharan Africa remains unknown. Methods: We monitored mortality among 306,000 residents of Kilifi Health and Demographic Surveillance System, Kenya, through four COVID-19 waves from April 2020-September 2021. We calculated expected deaths using negative binomial regression fitted to baseline mortality data (2010-2019) and calculated excess mortality as observed-minus-expected deaths. We excluded deaths in infancy because of under-ascertainment of births during lockdown. In February 2021, after two waves of wild-type COVID-19, adult seroprevalence of anti-SARS-CoV-2 was 25.1%. We predicted COVID-19-attributable deaths as the product of age-specific seroprevalence, population size and global infection fatality ratios (IFR). We examined changes in cause of death by Verbal Autopsy (VA). Results: Between April 2020 and February 2021, we observed 1,000 deaths against 1,012 expected deaths (excess mortality -1.2%, 95% PI -6.6%, 5.8%). Based on SARS-CoV-2 seroprevalence, we predicted 306 COVID-19-attributable deaths (a predicted excess mortality of 30.6%) within this period. Monthly mortality analyses showed a significant excess among adults aged [≥]45 years in only two months, July-August 2021, coinciding with the fourth (Delta) wave of COVID-19. By September 2021, overall excess mortality was 3.2% (95% PI -0.6%, 8.1%) and cumulative excess mortality risk was 18.7/100,000. By VA, there was a transient reduction in deaths attributable to acute respiratory infections in 2020. Conclusions: Normal mortality rates during extensive transmission of wild-type SARS-CoV-2 through February 2021 suggests that the IFR for this variant is lower in Kenya than elsewhere. We found excess mortality associated with the Delta variant but the cumulative excess mortality risk remains low in coastal Kenya compared to global estimates.

Child Mortality in England During the First Year of the COVID-19 Pandemic (preprint)

OBJECTIVESThe aim of this analysis was to quantify the relative risk of childhood deaths across the whole of England during the first year of the COVID pandemic, compared to a similar period of 2019. DESIGNThis work is based on data collected by the National Child Mortality Database (NCMD) which collates data on all children who die in England. The number of deaths, and their characteristics, from 1st April 2020 until 31st of March 2021 (2020-21), were compared to those from the same period of 2019-20. Relative risk and excess mortality were derived for deaths in 2020-21 vs 2019-20. SETTINGAll deaths reported to NCMD in England of children under 18 years of age, between April 2019 and March 2021. PARTICIPANTS6490 deaths of children, under the age of 18 years, reported to the NCMD over the study period. RESULTSChildren who died between April 2020 and March 2021 had similar demographics to those who died in 2019-20. Overall, there were 356 (198 to 514) fewer deaths in 2020-21 than in 2019-20 (RR 0.90 (0.85-0.94), p<0.001). Repeating the analysis by category of death, suggested that deaths from infection (RR 0.49 (0.38-0.64)) and from other underlying medical conditions (RR 0.75 (0.68-0.82)) were lower in 2020-21 than 2019-20, and weak evidence (p=0.074) that this was also true of deaths from substance abuse. CONCLUSIONSChildhood mortality in England during the first year of the SARS-CoV-2 pandemic was the lowest on record, with over 300 fewer deaths than the preceding 12 months. The greatest reduction was seen in children less than 10 years old. It is important that we learn from this effect, that potentially offers alternative ways to improve the outcome for the most vulnerable children in our society.

Child Suicide Rates During the COVID-19 pandemic in England (preprint)

Background: There is concern about the impact of COVID-19, and the control measures to prevent the spread, on children's mental health. The aim of this work was to identify if there had been a rise of childhood suicide during the COVID pandemic; using data from England's National Child Mortality Database (NCMD). Method: Child suicide rates between April to December 2020 were compared with those in 2019 using negative binomial regression models, and characteristics compared. In a subset (1st January to 17th May 2020) further characteristics and possible contributing factors were obtained. Results: A total of 193 likely childhood deaths by suicide were reported. There was no evidence overall suicide deaths were higher in 2020 than 2019 (RR 1.09 (0.80-1.48), p=0.584) but weak evidence that the rate in the first lockdown period (April to May 2020) was higher than the corresponding period in 2019 (RR 1.56 (0.86-2.81), p=0.144). Characteristics of individuals were similar between periods. Restriction to education and other activities, disruption to care and support services, tensions at home and isolation appeared to be contributing factors. Limitations: As child suicides are fortunately rare, the analysis is based on small numbers of deaths with limited statistical power to detect anything but major increases in incidence. Conclusion: We found no consistent evidence that child suicide deaths increased during the COVID-19 pandemic although there was a concerning signal they may have increased during the first UK lockdown. A similar peak was not seen during the following months, or the second lockdown.

Co-infection in critically ill patients with COVID-19: An observational cohort study from England (preprint)

Objective: To describe the incidence and nature of co-infection in critically ill adults with COVID-19 infection in England. Methods: A retrospective cohort study of adults with COVID-19 admitted to seven intensive care units (ICUs) in England up to 18 May 2020, was performed. Patients with completed ICU stays were included. The proportion and type of organisms were determined at <48 and >48 hours following hospital admission, corresponding to community and hospital-acquired co-infections. Results: Of 254 patients studied (median age 59 years (IQR 49-69); 64.6% male), 139 clinically significant organisms were identified from 83(32.7%) patients. Bacterial co-infections were identified within 48 hours of admission in 14(5.5%) patients; the commonest pathogens were Staphylococcus aureus (four patients) and Streptococcus pneumoniae (two patients). The proportion of pathogens detected increased with duration of ICU stay, consisting largely of Gram-negative bacteria, particularly Klebsiella pneumoniae and Escherichia coli. The co-infection rate >48 hours after admission was 27/1000 person-days (95% CI 21.3-34.1). Patients with co-infections were more likely to die in ICU (crude OR 1.78,95% CI 1.03-3.08, p=0.04) compared to those without co-infections. Conclusion: We found limited evidence for community-acquired bacterial co-infection in hospitalised adults with COVID-19, but a high rate of Gram-negative infection acquired during ICU stay.