Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules

Tesis por compendio[EN] Abstract The present PhD thesis entitled "Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules" is based on the application of supramolecular chemistry and material science principles for the development of optical chemosensors for anions and neutral molecules detection. The second chapter of this PhD thesis is devoted to the preparation of chemodosimeters for the chromo-fluorogenic detection of fluoride, diisopropyl fluorophosphates (DFP) and hydrogen sulfide. The optical detection of fluoride anion was achieved by using a pyridine derivative containing a t-butyldimethylsilyl ether group. Aqueous solutions of the chemodosimeter were colorless but turned yellow upon addition of fluoride anion. Also a remarkable enhancement in emission was observed only upon the addition of fluoride. The optical changes were ascribed to a fluoride-induced hydrolysis of the silyl ether moiety. Also a chemodosimeter for the optical recognition of DFP, a nerve agent simulant, was prepared. In this case, the chemodosimeter was based on a stilbene pyridinium derivative functionalized with hydroxyl and silyl ether moieties. Aqueous solutions of the chemodosimeter were colorless changing to yellow upon DFP addition. The optical changes were ascribed to a hydroxyl phosphorylation followed by a fluoride-induced hydrolysis of the silyl ether group. Besides, that probe was implemented in test strips and DFP detection in gas phase was accomplished. Finally, the fluorogenic recognition of hydrogen sulfide anion was explored. For this purpose different fluorophores were selected and fucntionalized with 2,4-dinitrophenyl ether groups. The prepared probes were neraly non-emissive but remarkable emission enhancements upon addition of hydrogen sulfide were observed. The emission enhancements observed were due to a selective sulfide-induced hydrolysis of the 2,4-dinitrophenyl ether moiety that yielded the free fluorophores. Another set of chemodosimeters equipped with azide and sulfonylazide moieties were prepared. Again these probes were non-fluorescent but upon addition of hydrogen sulfide an important enhancement in emission was found. The selective response was ascribed to a reduction of the azide and sulfonylazide moieties to amine and sulfonylamide induced by hydrogen sulfide anion. Besides, the viability assays showed that these dosimeters were essentially non-toxic and real-time fluorescence imaging measurements confirmed their ability to detect intracellular hydrogen sulfide at micromolar concentrations. The third chapter of this PhD thesis was devoted to the preparation of nanoscopic gated materials and their use in sensing protocols. In a first step a gated material for the optical detection of glutathione (GSH) was prepared. For this purpose MCM-41 mesoporous silca nanoparticles were selected as inorganic scaffold. The pores were loaded with safranine O and the external surface was functionalized with disulfide-containing oligo(ethylene glycol) moieties. Dye delivery from aqueous suspensions of the sensory material was only observed in the presence of GSH. The signalling paradigm was ascribed to the selective reduction of the disulfide bond by GSH which induced pore opening and dye release. Also capped organic-inorganic hybrid materials for the selective detection of hydrogen sulfide were prepared and characterized. In this case the same MCM-41 support was used and charged with [Ru(bipy)3]2+ dye. Then, the external surface was functionalized with Cu(II)-macorcyclic complexes and finally, the pores were capped by the addition of the bulky anion hexametaphosphate. Aqueous suspensions of this material showed negligible dye release whereas in the presence of hydrogen sulfide anion a remarkable colour change was observed. This optical response was ascribed to a demetallation process of the Cu(II) complex induced by hydrogen sulfide.[ES] Resumen La presente tesis doctoral titulada "Química supramolecular: Nuevos dosímetros químicos y materiales híbridos para la detección cromo-fluorogénica de aniones y moléculas neutras." está basada en la aplicación de principios básicos de la química supramolecular y de la ciencia de materiales en el desarrollo de sensores ópticos para aniones y moléculas neutras. El segundo capítulo de esta tesis doctoral está dedicado a la preparación de dosímetros químicos para la detección cromo-fluorogénica de fluoruro, diisopropil fluorofosfato (DFP) y sulfuro de hidrógeno. Para la detección óptica del anión fluoruro se sintetizó un derivado de piridina funcionalizado con un t-butildimetilsilil éter. En este capítulo también se describe la preparación de un dosímetro químico para la detección de DFP, que es un simulante de agentes nerviosos. Este dosímetro está basado en un estilbeno funcionalizado con una sal de piridinio que contiene grupos hidroxilo y silil éter en su estructura. Finalmente se prepararon dos familias de sensores para la detección óptica de hidrógeno sulfuro. La primera familia de sensores consiste en fluoróforos comunes funcionalizados con 2,4-dinitrofenil éteres. Los sensores preparados no presentaron una emisión de fluorescencia importante mientras que, en presencia del anión hidrógeno sulfuro, se observó un aumento significativo. La segunda familia de dosímetros también estaba compuesta por ciertos fluorofóros pero, en este caso, funcionalizados con grupos azida y sulfonilazida. Los dosimétros preparados, siguiendo esta segunda aproximación, tampoco dieron una fluorescencia significativa observándose un aumento de la misma al añadir el anión hidrógeno sulfuro. El tercer capítulo de esta tesis doctoral está dedicado a la preparación de materiales híbridos nanoscópicos funcionalizados con puertas moleculares y su aplicación en protocolos de reconocimiento. En primer lugar se preparó un material para la detección óptica de glutatión (GSH). Para ello se emplearon nanopartículas de MCM-41 mesoporosas como soporte inorgánico. Los poros del soporte fueron cargados con el colorante safranina O y la superficie externa funcionalizada con oligo(etilenglicol) conteniendo enlaces disulfuro. También se prepararon y caracterizaron varios materiales híbridos para la detección selectiva del anión hidrógeno sulfuro. En este caso también se empleó, como soporte inorgánico, sílice mesoporosa MCM-41. Los poros del soporte inorgánico fueron cargados con [Ru(bipy)3]2+ y la superficie externa funcionalizada con varios complejos macrocíclicos de Cu(II). El material sensor final fue obtenido al añadir el anion hexametafosfato, que compleja con los complejos de Cu(II), produciendo un bloqueo de los poros.[CA] Resum La present tesi doctoral titulada "Química supramolecular: Nous dosímetres químics i materials híbrids per a la detecció cromo-fluorogènica d'anions i molècules neutres." està basada en l'aplicació dels principis bàsics de la química supramolecular i de la ciència dels materials en el desenvolupament de sensors òptics per a anions i molècules neutres. El segon capítol d'aquesta tesi doctoral està dedicat a la preparació de dosímetres químics per a la detecció cromo-fluorogènica de fluorur, diisopropil fluorofosfat (DFP) i sulfur d'hidrogen. Per a la detecció òptica de l'anió fluorur es va sintetitzar un derivat de piridina funcionalitzat amb un t-dibutildimetilsilil èter. En aquest capítol també es descriu la preparació d'un dosímetre químic per a la detecció de DFP, que és un simulant d'agents nerviosos. Aquest dosímetre està basat en un estilbè funcionalitzat amb una sal de piridina que conté grups hidroxil i silis èter en la seua estructura. Finalment varen ser preparades dues famílies de sensors per a la detecció òptica de sulfur d'hidrogen. La primera família consisteix en fluoròfors comuns funcionalitzats amb 2,4-dinitrofenil èters. Els sensors preparats no presentaren una emissió de fluorescència significativa mentre que, en presencia de l'anió hidrogen sulfur, es va observar un augment significatiu. La segona família de dosímetres també estava composada per certs fluròfors però, en aquest cas, funcionalitzats amb grups azida i sulfonilazida. Els dosímetres preparats, seguint aquesta segona aproximació, tampoc donaren una fluorescència significativa observant-se un augment de la mateixa al afegir l'anió hidrogen sulfur. El tercer capítol d'aquesta tesi doctoral està dedicat a la preparació de materials híbrids nanoscòpics funcionalitzats amb portes moleculars i la seua aplicació en protocols de reconeixement. En primer lloc es va preparar un material per a la detecció òptica de glutatió (GSH). Per a aquest propòsit es varen emprar nanopartícules MCM-41 mesoporoses com a suport inorgànic. Els porus del suport varen ser carregats amb el colorant safranina O i la superfície externa funcionalitzada amb oligo(etilenglicol) que contenia enllaços disulfurs. També varen ser preparats i caracteritzats diversos materials híbrids per a la detecció selectiva de l'anió hidrogen sulfur. En aquest cas també es va emprar, com a suport inorgànic, sílice mesoporosa MCM-41. Els porus del suport inorgànic varen ser carregats amb [Ru(bipy)3]2+ i la superfície externa funcionalitzada amb diversos complexos macrocíclics de Cu(II). El material sensor final es va obtindre al afegir l'anió hexametafosfat, que es complexa amb macrocicles de Cu(II), produint un bloqueig dels porus.El Sayed Shehata Nasr, S. (2015). Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/52598TESISCompendi

Value of Oxygenation Index in Selecting Neonates for Thoracoscopic Repair of Congenital Diaphragmatic Hernia

Introduction: The major obstacles for routine application of thoracoscopic repair for congenital diaphragmatic hernia (CHH) in neonates include intraoperative hypercarbia, acidosis and conversion to open surgery. Therefore, strict preoperative selection criteria should be followed for successful primary thoracoscopic repair of the diaphragm and achievement of minimal conversion rate. Materials and Methods: A prospective study was conducted from April 2016 to March 2018, where all neonates confirmed to have CDH were assessed by a specialized anaesthesia team for the possibility of undergoing thoracoscopic repair. In order to assess the severity of persistent pulmonary hypertension (PPH), oxygenation index (OI) was used and babies who had OI <5 were considered to have mild pulmonary hypertension; and consequently underwent thoracoscopic repair. Results: Twenty nine CDH cases met the selection criteria; hence, they underwent thoracoscopic repair. Primary diaphragmatic repair was successfully performed thoracoscopically in all neonates without perioperative complication. Conversion to open repair occurred in 3 cases, with causes related to surgical factors. Recurrence was discovered in 1 case only. Conclusion: While choosing candidates for thoracoscopic CDH repair in neonates, OI is a reliable indicator as it clarifies neonates who have good preoperative pulmonary functio

Testing the Imperforate Anus Psychosocial Questionnaire (IAPSQ) on a Sample of Egyptian Children

Imperforate anus is a malformation of the anus, children with such type of congenital malformation usually undergo reconstructive surgery and be looked after by pediatric surgery nurses due to the problems with constipation and fecal incontinence after the colostomy is closed. Lack of control over bowels may affect a child’s psychosocial adjustment. The Aims of This Study are: (a) To evaluate the psychometric properties of the Arabic version of the Imperforate Anus Psychosocial Questionnaire (IAPSQ) on a sample of Egyptian children. (b) To assess the effect of (IA deformity, hypospadias, and rectal prolapse) on the psychosocial functioning of Egyptian children. (c) To compare the psychosocial functioning of children with congenital anomalies of the anus with those suffering from chronic diseases. Methodology: Subjects and Methods Study sample consisted of 35 children (with congenital anomalies of the anus) from Mansoura University Children’s Hospital (n=30), and Alexandria University Hospital (n=5), in Egypt. Data Collection: The data set of the current study was obtained within 3 months (from January to March 2017). Data Processing, Statistical Analysis and Results: Rasch analysis was used to evaluate the psychometric properties of the IAPSQ, as well as to generate the item difficulty and person ability measures. Analysis of the psychological dimension (23 items) gave a low person reliability (.37). With regard to the social dimension (12 items), the Rasch analysis showed a person reliability of .54. Comparisons between the Swedish Sample and the Egyptian Sample Psychological Domain: The Egyptian sample scored this item higher, indicating greater perceived concern by their mothers. it is more of a concerned for the Swedish sample compared to the Egyptian sample. Fathers are perceived by the Egyptian sample to be less loving and thinking more about their conditions compared to their mothers. Social Domain: Children distribution for this domain is also well spread out similar to the Swedish sample. Comparison between the two groups indicated that children with imperforate anus malformation has a higher quality of life (mean = 2.26 logits) compared to those children with chronic disease (mean = 1.78 logits). Reliability of measures is also higher for the study group (.76) compared to the comparison group (.41). The results of the DIF analysis showed that no significant DIF across the study and control group

Comparative study between purse–string suture and peritoneal disconnection with ligation techniques in the laparoscopic repair of inguinal hernia in infants and children

Background Laparoscopic hernia repair in children is becoming more popular nowadays. A lot of laparoscopic techniques were described to repair inguinal hernia in infants and children; however, there are few reports on laparoscopic disconnection of the hernia sac at internal inguinal ring (IIR) as a method for hernia repair.Purpose The objective of this study was to compare intracorporeal purse–string suturing leaving the hernia sac in continuity and laparoscopic disconnection of the hernia sac at IIR and proximal closure of the peritoneum for repair of inguinal hernia in infants and children. A randomized prospective study was carried out in the Pediatric Surgery Unit of Alexandria University Hospitals (Alexandria, Egypt) on 40 male children.Patients and methods Forty male patients (48 repairs) were randomized into two equal groups (n= 20). Group A was subjected to intracorporeal purse–string suturing around the IIR leaving the hernia sac in continuity. Group B was subjected to disconnection of the hernia sac from the parietal peritoneum at the level of IIR, followed by proximal closure of the peritoneum. Inclusion criteria were as follows: male inguinal hernia, either unilateral or bilateral, and age between 6 months and 12 years. Exclusion criteria were as follows: female inguinal hernia, hernia with undescended testicles, recurrent inguinal hernia, and previous major lower abdominal surgery. The main outcome measurement was recurrence, and secondary outcome measurements were operative time, hospital stay, intraoperative complications, postoperative hematoma, postoperative testicular atrophy, and postoperative hydrocele formation.Results There were no significant differences between the two groups as regards age, sex, and mode of presentation. All cases were completed laparoscopically without conversion. Group A showed a significantly higher rate of recurrence as well as hydrocele formation compared with group B; however, there was no difference as regards the operative time, hospital stay, and testicular atrophy.Conclusion Laparoscopic hernia repair using the peritoneal closure following disconnection of the hernia sac is a safe and feasible method for hernial repair with minimal complications. It has a lower recurrence rate compared with the purse–string suturing alone, with no added risk for injury to the vas and vessels

Comparative study between two-stage trans-abdominal Duhamel procedure and two-stage Soave pull-through in treatment of Hirschsprung’s disease: Clinical evaluation

Background: Hirschsprung’s disease (HD) is a congenital anomaly affecting the bowel of neonates, due to a defect in the ganglion cells presence in the colon in a caudo-cranial fashion, various surgical techniques used to correct the aganglionic segment, Duhamel procedure, Soave pull-through were used to correct the defect. Objectives: This study was conducted to compare the clinical outcome of two-stage Duhamel procedure and two-stage Soave pull-through in HD management. Patients and method: 40 patients diagnosed with Hirschsprung’s disease in the pediatric age group were enrolled in this study, 20 patients operated by Duhamel procedure, and 20 patients operated by Soave pull-through. Results: Enterocolitis was detected in 40% of patients after Soave pull-through while it was 5% in patients subjected to Duhamel procedure (p=0.020). Stricture was detected in 15% of cases subjected to Soave pull-through, Patients subjected to Duhamel procedure didn’t show stricture without significant difference. Regarding faecal continence, patients operated on by Duhamel procedure had better results compared to two-stage Soave pull-through (p<0.001). Regarding constipation, the differences were not significant between both groups. Conclusion: Two-stage trans-abdominal Duhamel procedure has significantly better results as regards post-operative continence, constipation, and enterocolitis than Soave endorectal pull-through in the management of HD

Modified Dismembered Technique of Laparoscopic Transperitoneal Pyeloplasty in Children

Background: Laparoscopic pyeloplasty in children gained more and more popularity over the past two decades. However, it remains technically challenging with the most steps of the procedure are ureteric spatulation, DJ insertion, and intracorporeal anastomosis. Many modifications have been proposed to address these issues. In this article, we present our surgical approach to laparoscopic transperitoneal modified dismembered pyeloplasty highlighting some tips to make it easy. Objectives: This study was conducted to evaluate the outcomes of laparoscopic management of ureteropelvic junction obstruction children. Patients and Methods: This was a prospective study carried out on patients who presented with UPJO to our center from May 2019 to October 2021. All the cases underwent laparoscopic transperitoneal modified dismembered pyeloplasty where complete dismembering is deferred after the ureteropelvic anastomosis to prevent ureteral torsion and to use the redundant pelvis as a handle for ureteric manipulation. We used 3 simple techniques for antegrade insertion of DJ. Results: The study included 25 patients (19 males and 6 females) The mean age at operation was 30.88 ± 27.48 months. The mean time needed for the anastomosis was 80 minutes while the mean total operative time was 155 minutes. No conversion was needed. Apart from 2 cases, all other patients showed significant improvement of the degree of hydronephrosis and renal split function. Conclusion: The described modifications facilitated performing the procedure rendering laparoscopic pyeloplasty to be a less demanding and much easier procedure than the conventional technique

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10&nbsp;years; 78.2% included were male with a median age of 37&nbsp;years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century