ABSTRACT
Introduction: The performance of a rapid test was evaluated against two ELISAs as a potentially useful tool to determine exposure to SARS-CoV-2 in low resource settings. A serosurvey was conducted in Kibera informal settlement, Nairobi, Kenya, where low numbers of COVID-19 were recorded during the pandemic. Materials: and methods A cross-sectional study was performed in 10 of 14 villages in Kibera informal settlement, Kenya’s largest slum community, in August 2021, before general vaccine roll-out. Participants were age one year and above with no symptoms of COVID-19. Capillary blood samples were tested using the Standard Q COVID-19 IgM/IgG Combo rapid test, Platelia SARS-CoV-2 Total Ab (IgM/IgG/IgA) Assay, and Wantai Total Ab (IgM/IgG/IgA) ELISA for SARS-CoV-2 which served as the reference test. Results: Samples were obtained from 438 participants; in 72 samples blood was insufficient for the Platelia ELISA. Specificity of the rapid test and Platelia ELISA were similar (>93%) but sensitivity was low (rapid test 61.3%; Platelia ELISA 83.4%). The Wantai ELISA showed greater positivity (82.6%) than the rapid test (51.8%) and Platelia ELISA (69.7%). Conclusions: The Wantai ELISA showed superior performance in this serosurvey. Point-of-care tests for convenient screening for SARS-CoV-2 exposure for surveillance studies need to be developed.
Subject(s)
COVID-19 , Severe Acute Respiratory SyndromeABSTRACT
The emergence and establishment of SARS CoV 2 variants of concern presented a major global public health crisis across the world. There were six waves of SARS CoV 2 cases in Kenya that corresponded with the introduction and eventual dominance of the major SARS-COV-2 variants of concern, excepting the first 2 waves that were both wildtype virus. We estimate that more than 1000 SARS CoV 2 introductions occurred in the two-year epidemic period (March 2020 to September 2022) and a total of 930 introductions were associated with variants of concern namely Beta (n=78), Alpha(n=108), Delta(n=239) and Omicron (n=505). A total of 29 introductions were associated with A.23.1 variant that circulated in high frequencies in Uganda and Rwanda. The actual number of introductions is likely to be higher than these conservative estimates due to limited genomic sequencing. Our data suggested that cryptic transmission was usually underway prior to the first real-time identification of a new variant, and that multiple introductions were responsible. Following emergence of each VOC and subsequent introduction, transmission patterns were associated with hotspots of transmission in Coast, Nairobi and Western Kenya and follows established land and air transport corridors. Understanding the introduction and dispersal of major circulating variants and identifying the sources of new introductions is important to inform public health control strategies within Kenya and the larger East-African region. Border control and case finding reactive to new variants is unlikely to be a successful control strategy.
ABSTRACT
Background The World Health Organization early warning indicators (EWIs) permit surveillance of factors associated with the emergence of HIV drug resistance (HIVDR). We examined cross- and within-region performance on HIVDR EWIs for selected HIV care and treatment clinics (CTCs) in five regions of southern Tanzania. Methods In 2016, we retrospectively collected EWI data from 50 CTCs for the January to December 2013 period. EWIs included the following: on time ART pick-up, retention on ART, ARV stockouts, and pharmacy prescribing and dispensing practices. Data for pediatric and adult people living with HIV were abstracted from source files, and frequencies and proportions were calculated for each EWI overall, as well as stratified by region, facility, and age group. Results Across and within all regions, on average, on-time pick-up of pills (63.0%), retention on ART (76.0%), and pharmacy stockouts (69.0%) were consistently poor for the pediatric population. Similarly, on-time pill pick up (66.0%), retention on ART (72.0%) and pharmacy stockouts (53.0%) for adults were also poor. By contrast, performance on pharmacy prescribing and dispensing practices were as desired for both pediatric and adult populations with few facility-level exceptions. Conclusion In this study, regions and facilities in the southern highlands of Tanzania reported widespread presence of HIVDR risk factors, including sub-optimal timeliness of pill pickup, retention on ART, and drug stockouts. Routine EWI monitoring provides a check on quality of service delivery, as well as affordable, large-scale surveillance for HIVDR risk factors. EWI monitoring remains relevant particularly in the context of new ART drug roll-out such as dolutegravir, during the COVID-19 pandemic when resultant HIV service disruptions require careful monitoring, and for virologic suppression as countries move closer to epidemic control.