Tracking SARS-CoV-2 variants through pandemic waves using RT-PCR testing in low-resource settings.

COVID-19 resulted in extensive morbidity and mortality worldwide. SARS-CoV-2 evolved rapidly, with increasing transmission due to Variants of Concern (VOC). Identifying VOC became important but genome submissions from low-middle income countries (LMIC) remained low leading to gaps in genomic epidemiology. We demonstrate the use of a specific mutation RT-PCR based approach to identify VOC in SARS-CoV-2 positive samples through the pandemic in Pakistan. We selected 2150 SARS-CoV-2 PCR positive respiratory specimens tested between April 2021 and February 2022, at the Aga Khan University Hospital Clinical Laboratories, Karachi, Pakistan. Commercially available RT-PCR assays were used as required for mutations in Spike protein (N501Y, A570D, E484K, K417N, L452R, P681R and deletion69_70) to identify Alpha, Beta, Gamma, Delta, and Omicron variants respectively. Three pandemic waves associated with Alpha, Delta and Omicron occurred during the study period. Of the samples screened, VOC were identified in 81.7% of cases comprising mainly; Delta (37.2%), Alpha (29.8%) and Omicron (17.1%) variants. During 2021, Alpha variants were predominant in April and May; Beta and Gamma variants emerged in May and peaked in June; the Delta variant peaked in July and remained predominant until November. Omicron (BA.1) emerged in December 2021 and remained predominant until February 2022. The CT values of Alpha, Beta, Gamma and Delta were all significantly higher than that of Omicron variants (p<0.0001). We observed VOC through the pandemic waves using spike mutation specific RT-PCR assays. We show the spike mutation specific RT-PCR assay is a rapid, low-cost and adaptable for the identification of VOC as an adjunct approach to NGS to effectively inform the public health response. Further, by associating the VOC with CT values of its diagnostic PCR we gain information regarding the viral load of samples and therefore the level of transmission and disease severity in the population.

Using rapid antigen testing for early, safe return-to-work for healthcare personnel after SARS-CoV-2 infection in a healthcare system in Pakistan: A retrospective cross-sectional study.

Anticipating staff shortage during the Omicron variant surge, we modified the US Centers for Disease Control and Prevention's contingency guidelines at a healthcare system in Pakistan. Infected staff had a SARS-CoV-2 rapid antigen test after 5-7 days of isolation, to decide a safe return-to-work. This led to signifcant cost savings without compromising patient/staff safety.

Efficacy of heterologous boosting against SARS-CoV-2 using a recombinant interferon-armed fusion protein vaccine (V-01): a randomized, double-blind and placebo-controlled phase III trial.

Waning of neutralizing titres along with decline of protection efficacy after the second dose of COVID-19 vaccines was observed, including China-made inactivated vaccines. Efficacy of a heterologous boosting using one dose of a recombinant SARS-CoV-2 fusion protein vaccine (V-01) in inactivated vaccine-primed population was studied, aimed to restore the immunity. A randomized, double-blind and placebo-controlled phase III trial was conducted in healthy people aged 18 years or older in Pakistan and Malaysia. Each eligible participant received one dose of the V-01 vaccine developed by Livzon Mabpharm Inc. or placebo within the 3-6 months after the two-dose primary regimen, and was monitored for safety and efficacy. The primary endpoint was protection against confirmed symptomatic SARS-CoV-2 infection. A total of 10,218 participants were randomly assigned to receive a vaccine or placebo. Virus-neutralizing antibodies were assessed in 419 participants. A dramatic increase (11.3-fold; 128.3-1452.8) of neutralizing titres was measured in the V-01 group at 14 days after the booster. Over two months of surveillance, vaccine efficacy was 47.8% (95%CI: 22.6-64.7) according to the intention-to-treat principle. The most common adverse events were transient, mild-to-moderate pain at the injection site, fever, headache, and fatigue. Serious adverse events occurred almost equally in V-01 (0.12%) and placebo (0.16%) groups. The heterologous boosting with the V-01 vaccine was safe and efficacious, which could elicit robust humoral immunity under the epidemic of the Omicron variant.Trial registration: ClinicalTrials.gov identifier: NCT05096832.

Development of Evidence-Based COVID-19 Management Guidelines for Local Context: The Methodological Challenges.

Background: The coronavirus disease 2019 (COVID-19) pandemic has presented as a therapeutic challenge for clinicians worldwide due to its rapid spread along with evolving evidence and understanding of the disease. Internationally, recommendations to guide the management of COVID-19 have been created and updated continuously by the WHO and CDC, which have been locally adapted by different countries. Similarly, Pakistan's National Command Operation Center (NCOC), in its national COVID-19 management strategy, generated guidelines for national implementation. Keeping the guidelines updated has proved challenging globally and locally. Here, we present a summary of the process to assess the evidence, including a time-restricted systematic review based on NCOC Clinical Management Guidelines for COVID-19 Infections v4 published on 11th December 2020 version, correlating it with current recommendations and with input one of the guidelines authors, particularly noting the methodological challenges. Methods: We conducted a systematic review synthesizing global research on treatment options for COVID-19 hospitalized patients, limiting it to pharmacological interventions for hospitalized COVID-19 patients included in Pakistan's NCOC's national guidelines v4 published on 11th December 2020. Each treatment recommendation's strength and quality of evidence was assessed based on the grading of recommendations assessment, development, and evaluation (GRADE) methodology. These were then compared to the most current living WHO COVID-19 pharmacological treatment guidelines v7.1. One of the authors of the NCOC guidelines reviewed and commented on the findings as well. Results: We note that the data from our systematic review strongly supports corticosteroids use in treating severe and critically ill COVID-19 hospitalized patients correlating with WHO v7.1 guidelines 24 September 2021. However, evidence from our review and WHO v7.1 for the use of tocilizumab had some conflicting evidence, with data from our review until December 2020 supporting only a weak recommendation for its use, compared to the strong recommendation by the WHO for the use of tocilizumab in patients with severe or critical COVID-19 infection. Regarding the use of antibiotics and ivermectin use in treating COVID-19 hospitalized patients, data from our review and WHO v 7.1 recommend against their use. Conclusion: Research data about the efficacy and safety of pharmacological interventions to treat hospitalized patients with COVID-19 are rapidly evolving, and based on it, the evidence for or against recommendations changes accordingly. Our study illustrates the challenges of keeping up with the evidence; the recommendations were based on studies up till December 2021, and we have compared our recommendations with the WHO v7.1, which showed some significant changes in the use of pharmacological treatment options.

Evolutionary history and introduction of SARS-CoV-2 Alpha VOC/B.1.1.7 in Pakistan through international travelers.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to emerge, and their identification is important for the public health response to coronavirus disease 2019 (COVID-19). Genomic sequencing provides robust information but may not always be accessible, and therefore, mutation-based polymerase chain reaction (PCR) approaches can be used for rapid identification of known variants. International travelers arriving in Karachi between December 2020 and February 2021 were tested for SARS-CoV-2 by PCR. A subset of positive samples was tested for S-gene target failure (SGTF) on TaqPathTM COVID-19 (Thermo Fisher Scientific) and for mutations using the GSD NovaType SARS-CoV-2 (Eurofins Technologies) assays. Sequencing was conducted on the MinION platform (Oxford Nanopore Technologies). Bayesian phylogeographic inference was performed integrating the patients' travel history information. Of the thirty-five COVID-19 cases screened, thirteen had isolates with SGTF. The travelers transmitted infection to sixty-eight contact cases. The B.1.1.7 lineage was confirmed through sequencing and PCR. The phylogenetic analysis of sequence data available for six cases included four B.1.1.7 strains and one B.1.36 and B.1.1.212 lineage isolate. Phylogeographic modeling estimated at least three independent B.1.1.7 introductions into Karachi, Pakistan, originating from the UK. B.1.1.212 and B.1.36 were inferred to be introduced either from the UK or the travelers' layover location. We report the introduction of SARS-CoV-2 B.1.1.7 and other lineages in Pakistan by international travelers arriving via different flight routes. This highlights SARS-CoV-2 transmission through travel, importance of testing, and quarantine post-travel to prevent transmission of new strains, as well as recording detailed patients' metadata. Such results help inform policies on restricting travel from destinations where new highly transmissible variants have emerged.

VITT with inactivated SARS-CoV-2 vaccine - index case.

We report a case of vaccine-induced immune thrombotic thrombocytopenia (VITT) in a 73-year-old gentleman who presented with pulmonary embolism and thrombocytopenia, two weeks after receiving inactivated COVID-19 vaccine. He responded well to nonheparin anticoagulation with complete resolution of symptoms and platelet count.

Thrombosis with Thrombocytopenia Syndrome After Administration of AZD1222 or Ad26.COV2.S Vaccine for COVID-19: A Systematic Review.

BACKGROUND: Cases of thrombosis with thrombocytopenia syndrome (TTS) have been reported following vaccination with AZD1222 or Ad26.COV2.S. This review aimed to explore the pathophysiology, epidemiology, diagnosis, management, and prognosis of TTS. METHODS: A systematic review was conducted to identify evidence on TTS till 4th September 2021. Case reports and series reporting patient-level data were included. Descriptive statistics were reported and compared across patients with different sexes, age groups, vaccines, types of thrombosis, and outcomes. FINDINGS: Sixty-two studies reporting 160 cases were included from 16 countries. Patients were predominantly females with a median age of 42.50 (22) years. AZD1222 was administered to 140 patients (87·5%). TTS onset occurred in a median of 9 (4) days after vaccination. Venous thrombosis was most common (61.0%). Most patients developed cerebral venous sinus thrombosis (CVST; 66.3%). CVST was significantly more common in female vs male patients (p = 0·001) and in patients aged <45 years vs ≥45 years (p = 0·004). The mortality rate was 36.2%, and patients with suspected TTS, venous thrombosis, CVST, pulmonary embolism, or intraneural complications, patients not managed with non-heparin anticoagulants or IVIG, patients receiving platelet transfusions, and patients requiring intensive care unit admission, mechanical ventilation, or inpatient neurosurgery were more likely to expire than recover. INTERPRETATION: These findings help to understand the pathophysiology of TTS while also recommending diagnostic and management approaches to improve prognosis in patients. FUNDING: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The mystery of COVID-19 reinfections: A global systematic review and meta-analysis.

BACKGROUND: As the COVID-19 pandemic rages on, reports on disparities in vaccine roll out alongside COVID-19 reinfection have been emerging. We conducted a systematic review to assess the determinants and disease spectrum of COVID-19 reinfection. MATERIALS AND METHODS: A comprehensive search covering relevant databases was conducted for observational studies reporting Polymerase Chain Reaction (PCR) confirmed infection and reinfection cases. A quality assessment tool developed by the National Institute of Health (NIH) for the assessment of case series was utilized. Meta-analyses were performed using RevMan 5.3 for pooled proportions of findings in first infection and reinfection with a 95% confidence interval (CI). RESULTS: Eighty-one studies reporting 577 cases were included from 22 countries. The mean age of patients was 46.2 ± 18.9 years and 179 (31.0%) cases of comorbidities were reported. The average time duration between first infection and reinfection was 63.6 ± 48.9 days. During first infection and reinfection, fever was the most common symptom (41.4% and 36.4%, respectively) whilst anti-viral therapy was the most common treatment regimen administered (44.5% and 43.0%, respectively). Comparable odds of symptomatic presentation and management were reported for the two infections. However, a higher Intensive Care Unit (ICU) admission rate was observed in reinfection compared to first infection (10 vs 3). Ten deaths were reported with respiratory failure being the most common cause of death (7/10 deaths). CONCLUSION: Our findings support immunization practices given increased ICU admissions and mortality in reinfections. Our cohort serves as a guide for clinicians and authorities in devising an optimal strategy for controlling the pandemic. (249 words).

Upregulated type I interferon responses in asymptomatic COVID-19 infection are associated with improved clinical outcome.

Understanding key host protective mechanisms against SARS-CoV-2 infection can help improve treatment modalities for COVID-19. We used a blood transcriptome approach to study biomarkers associated with differing severity of COVID-19, comparing severe and mild Symptomatic disease with Asymptomatic COVID-19 and uninfected Controls. There was suppression of antigen presentation but upregulation of inflammatory and viral mRNA translation associated pathways in Symptomatic as compared with Asymptomatic cases. In severe COVID-19, CD177 a neutrophil marker, was upregulated while interferon stimulated genes (ISGs) were downregulated. Asymptomatic COVID-19 cases displayed upregulation of ISGs and humoral response genes with downregulation of ICAM3 and TLR8. Compared across the COVID-19 disease spectrum, we found type I interferon (IFN) responses to be significantly upregulated (IFNAR2, IRF2BP1, IRF4, MAVS, SAMHD1, TRIM1), or downregulated (SOCS3, IRF2BP2, IRF2BPL) in Asymptomatic as compared with mild and severe COVID-19, with the dysregulation of an increasing number of ISGs associated with progressive disease. These data suggest that initial early responses against SARS-CoV-2 may be effectively controlled by ISGs. Therefore, we hypothesize that treatment with type I interferons in the early stage of COVID-19 may limit disease progression by limiting SARS-CoV-2 in the host.

Are doctors protected enough during COVID-19 in South Asia?

BACKGROUND: The highly contagious nature of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) places physicians in South Asia at high risk of contracting the infection. Accordingly, we conducted this study to provide an updated account of physician deaths in South Asia during the COVID-19 pandemic and to analyze and compare the different characteristics associated with physician mortality amongst the countries of the region. METHODS: We performed a cross-sectional study by using published news reports on the websites of news agencies from 9 selected countries in South Asia. Our study included only those physicians and doctors who died after contracting COVID-19 from their respective workplaces. All available data about the country of origin, type of, sex, age, medical or surgical specialty, and date of death were included. RESULTS: The total number of physician deaths reported due to COVID-19 in our study was 170, with half (87/170, 51%) of the deaths reported from Iran. Male physician deaths were reported to be 145 (145/170 = 85%). Internal Medicine (58.43%) was the most severely affected sub-specialty. The highest physician mortality rate in the general population recorded in Afghanistan (27/1000 deaths). General physicians from India [OR = 11.00(95% CI = 1.06-114.08), p = 0.045] and public sector medical practitioners from Pakistan [aOR = 4.52 (95% CI = 1.18-17.33), p = 0.028] were showing significant mortality when compared with other regions in multivariate logistic regression. CONCLUSION: An increased number of physician deaths, owing to COVID-19, has been shown in South Asia. This could be due to decreased personal protective equipment and the poor health care management systems of the countries in the region to combat the pandemic. Future studies should provide detailed information of characteristics associated with physician mortalities along with the main complications arising due to the virus.

Higher entropy observed in SARS-CoV-2 genomes from the first COVID-19 wave in Pakistan.

BACKGROUND: We investigated the genome diversity of SARS-CoV-2 associated with the early COVID-19 period to investigate evolution of the virus in Pakistan. MATERIALS AND METHODS: We studied ninety SARS-CoV-2 strains isolated between March and October 2020. Whole genome sequences from our laboratory and available genomes were used to investigate phylogeny, genetic variantion and mutation rates of SARS-CoV-2 strains in Pakistan. Site specific entropy analysis compared mutation rates between strains isolated before and after June 2020. RESULTS: In March, strains belonging to L, S, V and GH clades were observed but by October, only L and GH strains were present. The highest diversity of clades was present in Sindh and Islamabad Capital Territory and the least in Punjab province. Initial introductions of SARS-CoV-2 GH (B.1.255, B.1) and S (A) clades were associated with overseas travelers. Additionally, GH (B.1.255, B.1, B.1.160, B.1.36), L (B, B.6, B.4), V (B.4) and S (A) clades were transmitted locally. SARS-CoV-2 genomes clustered with global strains except for ten which matched Pakistani isolates. RNA substitution rates were estimated at 5.86 x10-4. The most frequent mutations were 5' UTR 241C > T, Spike glycoprotein D614G, RNA dependent RNA polymerase (RdRp) P4715L and Orf3a Q57H. Strains up until June 2020 exhibited an overall higher mean and site-specific entropy as compared with sequences after June. Relative entropy was higher across GH as compared with GR and L clades. More sites were under selection pressure in GH strains but this was not significant for any particular site. CONCLUSIONS: The higher entropy and diversity observed in early pandemic as compared with later strains suggests increasing stability of the genomes in subsequent COVID-19 waves. This would likely lead to the selection of site-specific changes that are advantageous to the virus, as has been currently observed through the pandemic.

Discrepancy between PCR based SARS-CoV-2 tests suggests the need to re-evaluate diagnostic assays.

OBJECTIVE: We investigated the discrepancy between clinical and PCR-based diagnosis of COVID-19. We compared results of ten patients with mild to severe COVID-19. Respiratory samples from all cases were tested on the Roche SARS-CoV-2 (Cobas) assay, Filmarray RP2.1 (bioMereiux) and TaqPath™ COVID19 (Thermofisher) PCR assays. RESULTS: Laboratory records of ten patients with mild to severe COVID-19 were examined. Initially, respiratory samples from the patients were tested as negative on the SARS-CoV-2 Roche® assay. Further investigation using the BIOFIRE® Filmarray RP2.1 assay identified SARS-CoV-2 as the pathogen in all ten cases. To investigate possible discrepancies between PCR assays, additional testing was conducted using the TaqPath™ COVID19 PCR. Eight of ten samples were positive for SARS-CoV-2 on the TaqPath assay. Further, Spike gene target failures (SGTF) were identified in three of these eight cases. Discrepancy between the three PCR assays could be due to variation in PCR efficiencies of the amplification reactions or, variation at primer binding sites. Strains with SGTF indicate the presence of new SARS-CoV-2 variant strains. Regular modification of gene targets in diagnostic assays may be necessary to maintain robustness and accuracy of SARS-CoV-2 diagnostic assays to avoid reduced case detection, under-surveillance, and missed opportunities for control.

Clinical characteristics and outcomes of COVID-19: Experience at a major tertiary care center in Pakistan.

INTRODUCTION: Limited data exist on clinical characteristics and outcomes of hospitalized COVID-19 patients in low-middle income countries. We aimed to describe the clinical spectrum and outcomes of hospitalized COVID-19 patients at a tertiary-care center in Karachi, Pakistan. METHODOLOGY: We conducted an observational study of adult COVID-19 patients hospitalized between February-June 2020. Patients with a discharge diagnosis of COVID-19 and PCR positivity were included. We created logistic regression models to understand association of clinical characteristics with illness severity and in-hospital mortality. RESULTS: The study population comprised 445 patients [67% males, median age 53 (IQR 40-64) years]. Majority of patients (N = 268; 60%) had ≥ 1 co-morbid [37.5% hypertension, 36.4% diabetes]. In-hospital mortality was 13%. Age ≥ 60 (aOR] =1.92; 95 %CI = 1.23-3.03), shortness of breath (aOR=4.43; 95% CI=2.73-7.22), CRP ≥150mg/L (aOR:1.77; 95% CI=1.09-2.85), LDH ≥ 500 I.U/L (aOR:1.98; 95% CI=1.25-3.16), Neutrophil-to-Lymphocyte ratio (NLR) ≥5 (aOR:2.80; 95%CI = 1.77-4.42) and increase in serum creatinine (aOR:1.32; 95%CI=1.07-1.61) were independently associated with disease severity. Septic shock (aOR: 13.27; 95% CI=3.78-46.65), age ≥ 60 (aOR: 3.26; 95% CI=1.07-9.89), Ferritin ≥ 1500ng/ml (aOR: 3.78; 95% CI=1.21-11.8), NLR ≥ 5 (aOR: 4.04; 95% CI=1.14-14.35) and acute kidney injury (aOR: 5.52; 95% CI=1.78-17.06) were independent predictors of in-hospital mortality. CONCLUSIONS: We found multiple predictors to be independently associated with in-hospital mortality, except diabetes and gender. Compared to reports from other countries, the in-hospital mortality among COVID-19 patients was lower, despite a high burden of co-morbidities. Further research is required to explore reasons behind this dichotomy.

COVID-19-associated pulmonary aspergillosis (CAPA) in patients admitted with severe COVID-19 pneumonia: An observational study from Pakistan.

BACKGROUND: Invasive aspergillosis is a well-known complication of severe influenza pneumonia with acute respiratory distress syndrome (ARDS). However, recent studies are reporting emergence of aspergillosis in severe COVID-19 pneumonia, named as COVID-19-associated pulmonary aspergillosis (CAPA). METHODS: A retrospective observational study was conducted in patients with severe COVID-19 pneumonia from February 2020 to April 2020. Patients ≥18 years of age with clinical features and abnormal chest imaging with confirmed COVID-19 by RT-PCR for SARS-CoV-2 were included. CAPA was diagnosed based on clinical parameters, radiological findings and mycological data. Data were recorded on a structured proforma, and descriptive analysis was performed using Stata ver 12.1. RESULTS: A total of 147 patients with confirmed COVID-19 and 23 (15.6%) patients requiring ICU admission were identified. Aspergillus species were isolated from tracheal aspirates of nine (39.1%) patients, and of these, five patients (21.7%) were diagnosed with CAPA and four (17.4%) had Aspergillus colonisation. The mean age of patients with CAPA was 69 years (Median age: 71, IQR: 24, Range: 51-85), and 3/5 patients were male. The most frequent co-morbid was diabetes mellitus (4/5). The overall fatality rate of COVID-19 patients with aspergillosis was 44% (4/9). The cause of death was ARDS in all three patients with CAPA, and the median length of stay was 16 days (IQR: 10; Range 6-35 days). CONCLUSION: This study highlights the need for comparative studies to establish whether there is an association of aspergillosis and COVID-19 and the need for screening for fungal infections in severe COVID-19 patients with certain risk factors.