Hemolytic Uremic Syndrome: A Covid-19 Vaccine Reaction Case Report (preprint)

Hemolytic uremic syndrome (HUS) is associated with microthrombi ,mainly in the kidneys. It may be classified as typical HUS or atypical HUS (aHUS) .Majority of HUS occur in children (usually at 6 months of age), as a sequela of shigella infection. In aHUS, a genetic or sporadic insult causes dysfunction in the complement cascade, leading to complement deposition on endothelial cells, thickening of arterioles and capillaries, and endothelial swelling and detachment. Consequently, there is formation of obstructive thrombi in the vessel lumina and shearing of red blood cells, creating schistiocytes, that results in the triad of Coombs negative hemolytic anemia, renal impairment, and thrombocytopenia. We report a rare case of a 43-year-old black male who reacted to the 2nd booster dose (some 7 months after the 1st) of Astra Zeneca Covid-19 vaccine with aHUS. He had ophthalmoplegia, occipital headaches and suicidal ideation which all resolved on high dose oral prednisolone. The Astra Zeneca vaccine which uses a chimpanzee platform is the only one reported to have similar reactions and this is important to note and manage such potentially life threatening rare adverse event.

Contextualizing adverse event following immunization data of coronavirus disease 2019 (COVID-19) vaccines in VigiAccess: An approach for reducing COVID-19 vaccine hesitancy (preprint)

Introduction: Vaccination features high among the public health interventions that have contributed significantly to global health. Following the March 2020 declaration by the World Health Organization that coronavirus 2019 (COVID-19) is a global pandemic, several vaccines have been developed and administered to curb the spread of COVID-19. One of the threats to attaining adequate vaccination uptake for these relatively new vaccines are concerns people have about the adverse event following immunization (AEFI) information. This study sought to assess AEFIs reported on COVID-19 vaccines approved for use so far in VigiAccess and to make a case for why AEFIs data in the database must be interpreted with caution. Methods: The study followed a cross-sectional quantitative study design. VigiAccess was searched on November 10, 2021 for AEFIs reported so far for all the 12 approved COVID-19 vaccines. Data were captured among age groups, sex and continents of the world. Descriptive data were summarized using tables. Frequencies and percentages were used to categorize descriptive variables. No ethical approval was obtained before the commencement of the study as this was essentially a secondary data analysis of AEFI reports which cannot be linked to any individual. Consequently, there was no need for the informed consent process. Results: Overall, 2,457,386 AEFIs had been reported in VigiAccess. AEFIs were found to be highest among the 18-44 age group (39.7%) and lowest in vaccine recipients below 12 years (0.1%). AEFIs were more common in females than male vaccine recipients with over two-thirds of the vaccine recipients being females. Among the continents of the world, AEFI reports were highest for Europe (50%) and lowest for Africa (3%). The top 10 commonly reported AEFI types were as follows: general disorders and vaccine administrative site conditions (1,481,549, 60.1%), nervous system disorders (1,046,928, 42.6%), musculoskeletal and connective tissue disorders (704,657, 28.6%), gastrointestinal disorders (495,997, 20.2%), investigations with undesirable outcomes (341,677, 13.9%), skin and subcutaneous tissue disorders (335,932, 13.6%), respiratory, thoracic and mediastinal disorders (262,158, 10.6%), infections and infestations (180,873, 7.3%), vascular disorders (132,533, 5.3%) and injury, poisoning and procedural complications (122,519, 5%). Conclusion: The study showed that over 2 million COVID-19 AEFIs were spontaneously reported in VigiAccess, however, no causal relationships could be established between the vaccines and the AEFIs. The public accessing VigiAccess data should be made aware of this lack of association so that they may make well informed health decisions.