Development of 2400-2450 MHz Frequency Band RF Energy Harvesting System for Low-Power Device Operation.

Recently, there has been an increasing fascination for employing radio frequency (RF) energy harvesting techniques to energize various low-power devices by harnessing the ambient RF energy in the surroundings. This work outlines a novel advancement in RF energy harvesting (RFEH) technology, intending to power portable gadgets with minimal operating power demands. A high-gain receiver microstrip patch antenna was designed and tested to capture ambient RF residue, operating at 2450 MHz. Similarly, a two-stage Dickson voltage booster was developed and employed with the RFEH to transform the received RF signals into useful DC voltage signals. Additionally, an LC series circuit was utilized to ensure impedance matching between the antenna and rectifier, facilitating the extraction of maximum power from the developed prototype. The findings indicate that the developed rectifier attained a peak power conversion efficiency (PCE) of 64% when operating at an input power level of 0 dBm. During experimentation, the voltage booster demonstrated its capability to rectify a minimum input AC signal of only 50 mV, yielding a corresponding 180 mV output DC signal. Moreover, the maximum power of 4.60 µW was achieved when subjected to an input AC signal of 1500 mV with a load resistance of 470 kΩ. Finally, the devised RFEH was also tested in an open environment, receiving signals from Wi-Fi modems positioned at varying distances for evaluation.

Using a data-driven approach to define post-COVID conditions in US electronic health record data.

OBJECTIVE: To create a data-driven definition of post-COVID conditions (PCC) by directly measure changes in symptomatology before and after a first COVID episode. MATERIALS AND METHODS: Retrospective cohort study using Optum® de-identified Electronic Health Record (EHR) dataset from the United States of persons of any age April 2020-September 2021. For each person with COVID (ICD-10-CM U07.1 "COVID-19" or positive test result), we selected up to 3 comparators. The final COVID symptom score was computed as the sum of new diagnoses weighted by each diagnosis' ratio of incidence in COVID group relative to comparator group. For the subset of COVID cases diagnosed in September 2021, we compared the incidence of PCC using our data-driven definition with ICD-10-CM code U09.9 "Post-COVID Conditions", first available in the US October 2021. RESULTS: The final cohort contained 588,611 people with COVID, with mean age of 48 years and 38% male. Our definition identified 20% of persons developed PCC in follow-up. PCC incidence increased with age: (7.8% of persons aged 0-17, 17.3% aged 18-64, and 33.3% aged 65+) and did not change over time (20.0% among persons diagnosed with COVID in 2020 versus 20.3% in 2021). For cases diagnosed in September 2021, our definition identified 19.0% with PCC in follow-up as compared to 2.9% with U09.9 code in follow-up. CONCLUSION: Symptom and U09.9 code-based definitions alone captured different populations. Maximal capture may consider a combined approach, particularly before the availability and routine utilization of specific ICD-10 codes and with the lack consensus-based definitions on the syndrome.

Substantial health and economic burden of COVID-19 during the year after acute illness among US adults at high risk of severe COVID-19.

BACKGROUND: Post-COVID conditions encompass a range of long-term symptoms after SARS-CoV-2 infection. The potential clinical and economic burden in the United States is unclear. We evaluated diagnoses, medications, healthcare use, and medical costs before and after acute COVID-19 illness in US patients at high risk of severe COVID-19. METHODS: Eligible adults were diagnosed with COVID-19 from April 1 to May 31, 2020, had ≥ 1 condition placing them at risk of severe COVID-19, and were enrolled in Optum's de-identified Clinformatics® Data Mart Database for ≥ 12 months before and ≥ 13 months after COVID-19 diagnosis. Percentages of diagnoses, medications, resource use, and costs were calculated during baseline (12 months preceding diagnosis) and the post-acute phase (12 months after the 30-day acute phase of COVID-19). Data were stratified by age and COVID-19 severity. RESULTS: The cohort included 19,558 patients (aged 18-64 y, n = 9381; aged ≥ 65 y, n = 10,177). Compared with baseline, patients during the post-acute phase had increased percentages of blood disorders (16.3%), nervous system disorders (11.1%), and mental and behavioral disorders (7.7%), along with increases in related prescriptions. Overall, there were substantial increases in inpatient and outpatient healthcare utilization, along with a 23.0% increase in medical costs. Changes were greatest among older patients and those admitted to the intensive care unit for acute COVID-19 but were also observed in younger patients and those who did not require COVID-19 hospitalization. CONCLUSIONS: There is a significant clinical and economic burden of post-COVID conditions among US individuals at high risk for severe COVID-19.

Outcome of modified fleur-de-lis latissimus dorsi myocutaneous flap for breast reconstruction.

BACKGROUND: Reconstruction of breast following mastectomy is important in terms of rehabilitating patients of breast cancer. Numerous approaches have been used in the reconstruction process. A procedure that has gained interest of the patients is reconstruction of breast using the autologous form. Main objective of this study is to determine the outcomes of modified fleur-de-lis latissimus dorsi flap in patients undergoing breast reconstruction. METHODOLOGY: This is a retrospective case series which was conducted at the Department of Plastic Surgery, SIMS/Services Hospital, Lahore, from January 2020 till December 2022. 184 patients age 25-60 years and Females with a history of mastectomy, who had to undergo creation of breast shape using a tissue flap from another part of the body at the site of breast following mastectomy were included. All patients were subjected to standard procedure of breast reconstruction with latissimus dorsi flap using modified fleur-de-lis technique and postoperatively weekly assessment in the first month and then monthly until 3 months was carried out and outcome of the study was analysed. RESULTS: The mean age and VAS score of the patients was 49.7 ± 9.17 and 6 ± 2.21, respectively. 57.1 % patients have DCIS, benign in 38 % patients and other tumours were present in 4.9 % patients. Immediate versus delayed reconstruction was done in 63.6 % versus 36.4 % patients respectively. Good aesthetic outcome was achieved in 80.3 % patients CONCLUSION: Modified fleur-de-lis latissimus dorsi flap in patients undergoing breast reconstruction yielded a good aesthetic outcome in the majority of the patients.

Diagnosis of primary vitreoretinal lymphoma masquerading infectious retinitis by retinal biopsy.

PURPOSE: To report a case of primary vitreoretinal lymphoma masquerading as infectious retinitis that was diagnosed via a retinal biopsy. OBSERVATIONS: A 72-year-old female patient was referred to our ophthalmology clinic for evaluation of retinitis and vasculitis in the right eye (OD). On examination, best-corrected visual acuities (BCVAs) were hand motions OD and 20/20 in the left eye (OS). Fundus examination revealed optic disc edema and diffuse retinal whitening superior to the superotemporal arcade OD. Given the high suspicion of infectious retinitis, the patient was treated with intravitreal foscarnet, systemic acyclovir, and oral prednisone and underwent a comprehensive uveitis workup, which was unremarkable for viral and autoimmune entities. Given the patient's history of diffuse large B cell lymphoma with cutaneous involvement, vitreoretinal lymphoma was suspected, prompting pars plana vitrectomy with a retinal biopsy. Biopsy and immunohistochemistry results were consistent with B-cell lymphoma, and the patient was treated with high-dose methotrexate and rituximab. At 5-month follow-up, BCVAs were hand motions OD and 20/30 OS, and fundus examination demonstrated disc edema with resolution of retinal whitening OD. She responded well to the treatment with regression of vitreoretinal lymphoma on examination and is being monitored closely for lymphoma recurrence. CONCLUSIONS AND IMPORTANCE: Although uncommon, patients with vitreoretinal lymphoma may masquerade as infectious retinitis, and vitreoretinal lymphoma should be suspected when refractory to antiviral therapy and in the setting of a negative workup for viral etiologies. Vitrectomy with retinal biopsy may be considered to aid the diagnosis of vitreoretinal lymphoma although careful consideration of the risks and benefits is warranted.

RF energy harvesters for wireless sensors, state of the art, future prospects and challenges: a review.

The power consumption of portable gadgets, implantable medical devices (IMDs) and wireless sensor nodes (WSNs) has reduced significantly with the ongoing progression in low-power electronics and the swift advancement in nano and microfabrication. Energy harvesting techniques that extract and convert ambient energy into electrical power have been favored to operate such low-power devices as an alternative to batteries. Due to the expanded availability of radio frequency (RF) energy residue in the surroundings, radio frequency energy harvesters (RFEHs) for low-power devices have garnered notable attention in recent times. This work establishes a review study of RFEHs developed for the utilization of low-power devices. From the modest single band to the complex multiband circuitry, the work reviews state of the art of required circuitry for RFEH that contains a receiving antenna, impedance matching circuit, and an AC-DC rectifier. Furthermore, the advantages and disadvantages associated with various circuit architectures are comprehensively discussed. Moreover, the reported receiving antenna, impedance matching circuit, and an AC-DC rectifier are also compared to draw conclusions towards their implementations in RFEHs for sensors and biomedical devices applications.

Exploring the Interplay of the CRISPR-CAS System with Antibiotic Resistance in Staphylococcus aureus: A Poultry Meat Study from Lahore, Pakistan.

Staphylococcus aureus is one of the major pathogens responsible for causing food poisoning worldwide. The emergence of antibiotic resistance in this bacterium is influenced by various factors. Among them, bacterial acquired defense systems described as clustered regularly interspaced short palindromic repeats (CRISPR)-cas system might be involved in antibiotic resistance development in bacteria. The current study was designed to assess the prevalence of S. aureus and its antibiotic resistance profile and identify the relationship of the CRISPR-cas system with antimicrobial resistance, followed by phylogenetic analysis. Total samples (n = 188) of poultry meat were collected from the poultry bird market of Lahore, Punjab, Pakistan. We used both phenotypic (antibiotic disc diffusion) and genotypic methods (PCR) to identify multi-drug resistant (MDR) strains of S. aureus. Additionally, the role of the CRISPR-Cas system in the isolated MDR S. aureus was also assessed. In addition, real-time quantitative PCR (qRT-PCR) was used to evaluate the association of the CRISPR-cas system with antimicrobial resistance. All of the S. aureus isolates showed 100% resistance against erythromycin, 97.5% were resistant to tetracycline, and 75% were resistant to methicillin. Eleven isolates were MDR in the current study. The CRISPR system was found in all MDR isolates, and fifteen spacers were identified within the CRISPR locus. Furthermore, MDR S. aureus isolates and the standard strain showed higher expression levels of CRISPR-associated genes. The correlation of said system with MDR isolates points to foreign gene acquisition by horizontal transfer. Current knowledge could be utilized to tackle antibiotic-resistant bacteria, mainly S. aureus.

A Case of Persistent Macular Edema and a Disappearing Tattoo.

PURPOSE: To describe a case of macular edema (ME), uveitis, and a disappearing tattoo. METHODS: A single case report from a tertiary referral center. RESULTS: The patient described in the following case report developed ME 15 years after a recently acquired tattoo on his arm had developed an erythematous rash and subsequently spontaneously disappeared with pathology consistent with a granulomatous process. Chest imaging identified the development of hilar lymphadenopathy that had not been previously noted. CONCLUSIONS: This case represents a unique presentation of the delayed development of sarcoidosis many years after the patient had lost a tattoo to a dermal granulomatous reaction to the tattoo ink.

Effectiveness of BNT162b2 BA.4/5 Bivalent mRNA Vaccine Against Symptomatic COVID-19 Among Immunocompetent Individuals Testing at a Large US Retail Pharmacy.

BACKGROUND: Data on the effectiveness of BA.4/5 bivalent vaccine stratified by age and prior infection are lacking. METHODS: This test-negative study used data from individuals ≥5 years of age testing for SARS-CoV-2 with symptoms (15 September 2022 to 31 January 2023) at a large national retail pharmacy chain. The exposure was receipt of 2-4 wild-type doses and a BNT162b2 BA.4/5 bivalent vaccine (>2 months since last wild-type dose). The outcome was a positive SARS-CoV-2 test. Absolute (vs unvaccinated) and relative (vs 2-4 wild-type doses) vaccine effectiveness (VE) were calculated as (1 - adjusted odds ratio from logistic regression) × 100. VE was stratified by age and self-reported prior infection. RESULTS: Overall, 307 885 SARS-CoV-2 tests were included (7916 aged 5-11, 16 329 aged 12-17, and 283 640 aged ≥18 years). SARS-CoV-2 positivity was 39%; 21% were unvaccinated, 70% received 2-4 wild-type doses with no bivalent vaccine, and 9% received a BNT162b2 BA.4/5 bivalent dose. At a median of 1-2 months after BNT162b2 BA.4/5 bivalent vaccination, depending on age group, absolute VE was 22%-60% and was significantly higher among those reporting prior infection (range, 55%-79%) than not (range, no protection to 50%). Relative VE was 31%-64%. CONCLUSIONS: BNT162b2 BA.4/5 bivalent showed early additional protection against Omicron-related symptomatic COVID-19, with hybrid immunity offering greater protection.

Utility of a nitinol stone extractor for intraocular foreign body removal.

Purpose: To describe the novel application of a urological instrument, the nitinol stone basket, in the removal of a retained intraocular foreign body (IOFB). Observations: This is a retrospective case series describing two eyes of two patients presenting with metallic IOFBs after hammering metal-on-metal. Both patients underwent 23-gauge pars plana vitrectomy (PPV) and successful IOFB extraction using the NCircle® Nitinol Tipless Stone Extractor. There were no intraoperative or post-surgical complications. Both patients demonstrated improvement in vision, with most recent postoperative visual acuities of 20/40 and 20/60. Conclusions and importance: The nitinol stone basket may be considered for removal of IOFBs, particularly larger IOFBs that are difficult to grasp with forceps. Our cases add to the literature showing favorable visual outcomes and few complications in the post-operative period using this technique.

Clinical outcomes of COVID-19 and influenza in hospitalized children <5 years in the US.

Introduction: We compared hospitalization outcomes of young children hospitalized with COVID-19 to those hospitalized with influenza in the United States. Methods: Patients aged 0-<5 years hospitalized with an admission diagnosis of acute COVID-19 (April 2021-March 2022) or influenza (April 2019-March 2020) were selected from the PINC AI Healthcare Database Special Release. Hospitalization outcomes included length of stay (LOS), intensive care unit (ICU) admission, oxygen supplementation, and mechanical ventilation (MV). Inverse probability of treatment weighting was used to adjust for confounders in logistic regression analyses. Results: Among children hospitalized with COVID-19 (n = 4,839; median age: 0 years), 21.3% had an ICU admission, 19.6% received oxygen supplementation, 7.9% received MV support, and 0.5% died. Among children hospitalized with influenza (n = 4,349; median age: 1 year), 17.4% were admitted to the ICU, 26.7% received oxygen supplementation, 7.6% received MV support, and 0.3% died. Compared to children hospitalized with influenza, those with COVID-19 were more likely to have an ICU admission (adjusted odds ratio [aOR]: 1.34; 95% confidence interval [CI]: 1.21-1.48). However, children with COVID-19 were less likely to receive oxygen supplementation (aOR: 0.71; 95% CI: 0.64-0.78), have a prolonged LOS (aOR: 0.81; 95% CI: 0.75-0.88), or a prolonged ICU stay (aOR: 0.56; 95% CI: 0.46-0.68). The likelihood of receiving MV was similar (aOR: 0.94; 95% CI: 0.81, 1.1). Conclusions: Hospitalized children with either SARS-CoV-2 or influenza had severe complications including ICU admission and oxygen supplementation. Nearly 10% received MV support. Both SARS-CoV-2 and influenza have the potential to cause severe illness in young children.

Vogt-Koyanagi-Harada-like Syndrome Induced by Checkpoint Inhibitor Cemiplimab.

Checkpoint inhibition targeting programmed cell-death protein 1 has demonstrated efficacy for a wide range of indications including cutaneous malignancy. However, immune-related adverse events (irAEs), including infrequent but visually impactful ocular irAEs, require careful consideration of treatment options, including medication withdrawal, local corticosteroids, or rarely immunomodulation. This case presents a 53-year-old woman who developed uveitis and mucous membrane ulcers after treatment for numerous cutaneous neoplasms, primarily squamous cell carcinoma, with the programmed cell-death protein 1 inhibitor cemiplimab. Ophthalmic examination revealed diffuse choroidal depigmentation consistent with a Vogt-Koyanagi-Harada-like syndrome. Topical and periocular steroids were used to treat the intraocular inflammation, and cemiplimab was discontinued. Because of ongoing severe uveitis, systemic corticosteroids and corticosteroid-sparing immunosuppression were initiated. Specifically, azathioprine and methotrexate were introduced, but each was stopped due to side effects, prompting the initiation of adalimumab (ADA) treatment. While ADA controlled intraocular inflammation, the squamous cell carcinomas were noted to progress, resulting in the discontinuation of ADA. However, a uveitis recurrence was observed. After a discussion of risks and benefits of biologic immunosuppressive therapy, including the risk of vision loss, ADA was restarted with successful disease quiescence at a 16-month follow-up. The cutaneous neoplasms were managed with topical and intralesional therapies, such as 5-fluorouracil. Recent dermatologic examinations suggested no new cutaneous lesions. This scenario presents the effective use of ADA in an ocular irAE that balances the management of sight-threatening ocular inflammation with the risk of promoting recurrent or de novo neoplastic disease.

Management of Atypical Central Serous Chorioretinopathy Mimicking Vogt-Koyanagi-Harada Disease.

Purpose: To report a case of multifocal central serous chorioretinopathy (CSCR) mimicking Vogt-Koyanagi-Harada (VKH) disease. Methods: A 42-year-old man was evaluated for an exudative retinal detachment (RD) with a presumptive diagnosis of VKH while being treated with corticosteroids. The examination showed subretinal fibrin deposition with a bullous, exudative, macula-involved RD in the left eye and a progressive decline in visual acuity (VA) to hand motions. Multimodal imaging showed multifocal hyperfluorescent leaks bilaterally by angiography, highly suggestive of CSCR exacerbated by corticosteroids. Results: After the multifocal CSCR diagnosis, the systemic corticosteroids were tapered and eventually discontinued. The patient was then managed with focal laser photocoagulation, photodynamic therapy, and acetazolamide. The VA improved to 20/30 with complete resolution of the bullous RD at the 12-month follow-up. Conclusions: Extensive bullous RD with subretinal fibrin deposition is an infrequent manifestation of CSCR commonly associated with corticosteroid use that can mimic VKH. Thus, it is important to distinguish CSCR from VKH and the potential of combination therapy in managing chronic multifocal CSCR with a bullous RD.

The impact of COVID-19 vaccination in the US: Averted burden of SARS-COV-2-related cases, hospitalizations and deaths.

By August 1, 2022, the SARS-CoV-2 virus had caused over 90 million cases of COVID-19 and one million deaths in the United States. Since December 2020, SARS-CoV-2 vaccines have been a key component of US pandemic response; however, the impacts of vaccination are not easily quantified. Here, we use a dynamic county-scale metapopulation model to estimate the number of cases, hospitalizations, and deaths averted due to vaccination during the first six months of vaccine availability. We estimate that COVID-19 vaccination was associated with over 8 million fewer confirmed cases, over 120 thousand fewer deaths, and 700 thousand fewer hospitalizations during the first six months of the campaign.

Seasonal trends in COVID-19 cases, hospitalizations, and mortality in the United States and Europe.

Determining whether SARS-CoV-2 exhibits seasonality like other respiratory viruses is critical for public health planning. We evaluated whether COVID-19 rates follow a seasonal pattern using time series models. We used time series decomposition to extract the annual seasonal component of COVID-19 case, hospitalization, and mortality rates from March 2020 through December 2022 for the United States and Europe. Models were adjusted for a country-specific stringency index to account for confounding by various interventions. Despite year-round disease activity, we identified seasonal spikes in COVID-19 from approximately November through April for all outcomes and in all countries. Our results support employing annual preventative measures against SARS-CoV-2, such as administering seasonal booster vaccines in a similar timeframe as those in place for influenza. Whether certain high-risk individuals may need more than one COVID-19 vaccine booster dose each year will depend on factors like vaccine durability against severe illness and levels of year-round disease activity.

Coronavirus Disease 2019 Severity and Risk of Subsequent Cardiovascular Events.

BACKGROUND: Little is known about the relationship between coronavirus disease 2019 (COVID-19) severity and subsequent risk of experiencing a cardiovascular event (CVE) after COVID-19 recovery. We evaluated this relationship in a large cohort of United States adults. METHODS: Using a claims database, we performed a retrospective cohort study of adults diagnosed with COVID-19 between 1 April 2020 and 31 May 2021. We evaluated the association between COVID-19 severity and risk of CVE >30 days after COVID-19 diagnosis using inverse probability of treatment-weighted competing risks regression. Severity was based on level of care required for COVID-19 treatment: intensive care unit (ICU) admission, non-ICU hospitalization, or outpatient care only. RESULTS: A total of 1 357 518 COVID-19 patients were included (2% ICU, 3% non-ICU hospitalization, and 95% outpatient only). Compared to outpatients, there was an increased risk of any CVE for patients requiring ICU admission (adjusted hazard ratio [aHR], 1.80 [95% confidence interval {CI}, 1.71-1.89]) or non-ICU hospitalization (aHR, 1.28 [95% CI, 1.24-1.33]). Risk of subsequent hospitalization for CVE was even higher (aHRs, 3.47 [95% CI, 3.20-3.76] for ICU and 1.96 [95% CI, 1.85-2.09] for non-ICU hospitalized vs outpatient only). CONCLUSIONS: COVID-19 patients hospitalized or requiring critical care had a significantly higher risk of experiencing and being hospitalized for post-COVID-19 CVE than patients with milder COVID-19 who were managed solely in the outpatient setting, even after adjusting for differences between these groups. These findings underscore the continued importance of preventing severe acute respiratory syndrome coronavirus 2 infection from progressing to severe illness to reduce potential long-term cardiovascular complications.

A Retrospective Follow-Up Study To Show The Effectiveness Of Booster Dose Of Foam Sclerotherapy Session At 3rd And 6th Months In Preventing The Recurrence Of Varicose Veins.

BACKGROUND: Injection sclerotherapy administration is known to cause a decreased recurrence of varicose vein disease. This research aimed to investigate the recurrence of varicose vein disease after giving booster doses of injection sclerotherapy. The booster doses were given at 3rd and 6th months. METHODS: One hundred and fifty patients participated and all patient's included ages 30-70 in the category of 'low risk' patients. The patients were both males and females. Patients participating in the study were counselled appropriately and written consent was taken from them. Moreover, the patients selected were volunteers and agreed to be part of the study. Patients who were above 70 years of age, those who were at a high-risk due to some co-morbidities (high-risk patients), patients not willing to be part of the study, those allergic to drugs being used including sclerosant and people with any known psychiatric illness or cardiac arrhythmias, deep venous thrombosis patients, patients having arteriovenous malformation/venous ulcers were all excluded. If the patient was pregnant, the gynaecology team was taken on board and the procedure was carried out. Every procedure was carried out under the direct supervision of the supervisor. Booster dose sessions of Foam Sclerotherapy were held at 3rd and 6th months of the study time. Their effectiveness was observed and documentation was carried out. RESULTS: Since it was a procedure that could be done in the OPD, there was no need for specialized anaesthesia care. It is of significant notice that when a patient of varicose veins was given a booster intravenous sclerosant injection at 3rd and 6th month of treatment, chances of recurrence decreased to 50%.

Double Stab Excision Arteriotomy-A Novel Technique For A Better Outcome.

BACKGROUND: This study was carried out to introduce a new technique of excision arteriotomy and to compare it with standard excision arteriotomy in terms of achieving desired size, shape and margins with minimal technical problems. METHODS: This was a comparative study carried out at the Vascular Surgery Unit of Combined Military Hospital Peshawar between January and September 2022. A total of 150 patients of chronic renal failure undergoing Arteriovenous access fulfilling the inclusion criteria were enrolled in our study. The patients were randomized into two groups, 75 in each group: Group A consisted of patients who underwent Conventional excision arteriotomy and Group B underwent Double Stab excision Arteriotomy. The endpoint of the study was to achieve an appropriate arteriotomy of the desired size and shape by having regular margins without intimal dissection during its formation or otherwise inappropriate arteriotomy if any of the criteria is not met. RESULTS: Among the total 150 patients included in our study, Ages ranged between 30-60 years and a mean age of 52.5 years. There were 82 (54.66%) males and 68 (45.33%) females with a male-to-female ratio of 1.2:1. In group A (Conventional Excision arteriotomy) there were 30 (40%) inappropriate arteriotomies and 45 (60%) appropriate arteriotomies. Among the total 30(40%) inappropriate arteriotomies in group A, larger than desired size arteriotomies were 10 cases (33.33%) followed by smaller than desired size arteriotomies; 6 (20%), irregular margins 9 (30%), intimal dissection 3(10%) & lateral tear 2 (6.66%) respectively. In group B of double stab excision arteriotomies, appropriate arteriotomies were achieved in 69 (92%) while the rest had inappropriate arteriotomies in 6 (8%). Among the total 6 (8%) inappropriate arteriotomies in group B, larger than desired size arteriotomies were 2 (33.33%), smaller than desired size arteriotomy; 1 (16.66%), irregular margins 1 (16.66%), intimal dissection;2 (33.33%) & no lateral tear respectively. CONCLUSIONS: This study concluded that the Double stab excision arteriotomy technique is superior to the conventional excision arteriotomy technique. The advantages of our technique are; its reliability with a short learning curve and can be performed precisely and safely.

Estimated BNT162b2 Vaccine Effectiveness Against Infection With Delta and Omicron Variants Among US Children 5 to 11 Years of Age.

Importance: Data describing the vaccine effectiveness (VE) and durability of BNT162b2 among children 5 to 11 years of age are needed. Objective: To estimate BNT162b2 VE against SARS-CoV-2 infection among children aged 5 to 11 years during Delta and Omicron variant-predominant periods and to further assess VE according to prior SARS-CoV-2 infection status and by sublineage during the Omicron variant-predominant period. Design, Setting, and Participants: This test-negative case-control study was conducted from November 2 to December 9, 2021 (Delta variant), and from January 16 to September 30, 2022 (Omicron variant), among 160 002 children tested at a large national US retail pharmacy chain, for SARS-CoV-2 via polymerase chain reaction (PCR); 62 719 children were tested during the Delta period, and 97 283 were tested during the Omicron period. Exposure: Vaccination with BNT162b2 before SARS-CoV-2 testing vs no vaccination. Main Outcomes and Measures: The primary outcome was SARS-CoV-2 infection confirmed by PCR (regardless of the presence of symptoms), and the secondary outcome was confirmed symptomatic infection. Adjusted estimated VE was calculated from multilevel logistic regression models. Results: A total of 39 117 children tested positive and 131 686 tested negative for SARS-CoV-2 (total, 170 803; 84 487 [49%] were boys; mean [SD] age was 9 [2] years; 74 236 [43%] were White non-Hispanic or non-Latino; and 37 318 [22%] were Hispanic or Latino). Final VE analyses included 160 002 children without SARS-CoV-2 infection less than 90 days prior. The VE of 2 doses of BNT162b2 against Delta was 85% (95% CI, 80%-89%; median follow-up, 1 month) compared with the Omicron period (20% [95% CI, 17%-23%]; median follow-up, 4 months). The adjusted VE of 2 doses against Omicron at less than 3 months was 39% (95% CI, 36%-42%), and at 3 months or more, it was -1% (95% CI, -6% to 3%). Protection against Omicron was higher among children with vs without infection 90 days or more prior but decreased in all children approximately 3 months after the second dose (58% [95% CI, 49%-66%] with infection vs 37% [95% CI, 34%-41%] without infection at <3 months; 27% [95% CI, 17%-35%] with infection vs -7% [95% CI, -12% to -1%] at ≥3 months without infection). The VE of 2 doses of BNT162b2 at less than 3 months by Omicron sublineage was 40% (95% CI, 36%-43%) for BA.1, 32% (95% CI, 21%-41%) for BA.2/BA.2.12.1, and 50% (95% CI, 37%-60%) for BA.4/BA.5. After 3 months or more, VE was nonsignificant for BA.2/BA.2.12.1 and BA.4/BA.5. The VE of a booster dose was 55% (95% CI, 50%-60%) against Omicron, with no evidence of waning at 3 months or more. Conclusions and Relevance: This study suggests that, among children aged 5 to 11 years, 2 doses of BNT162b2 provided modest short-term protection against Omicron infection that was higher for those with prior infection; however, VE waned after approximately 3 months in all children. A booster dose restored protection against Omicron and was maintained for at least 3 months. These findings highlight the continued importance of booster vaccination regardless of history of prior COVID-19.

US County-Level COVID-19 Vaccine Uptake and Rates of Omicron Cases and Deaths.

The population-level impact of vaccination on Omicron-related disease is not well described. We fit negative binomial models to estimate the relationship between US county-level vaccine coverage and rates of coronavirus disease 2019. Increased booster dose uptake was associated with lower rates of Omicron cases and deaths and is critical to combat future severe acute respiratory syndrome coronavirus 2 waves.