Breakthrough cases of Omicron and Delta variants of SARS-CoV-2 during the fifth wave in Pakistan.

COVID-19 pandemic has severely affected Pakistan with 1,557,134 cases as of August 4, 2022. However, the data regarding breakthrough infections in Pakistan is scant. Hence, the objective was to analyze SARS-CoV-2 breakthrough infections with respect to vaccines and variants during the fifth wave in Pakistan. Therefore, the Department of Virology (NIH, Pakistan) genotyped 2,467 randomly selected individuals between November 2021 and February 2022 using the SNPsig® SARS-CoV-2 (EscapePLEX) kit (PrimerDesign, UK). P681R and K417N mutations were used to distinguish delta and omicron. Data on the patient's age, gender, date of collection, variant, and vaccination status were analyzed using Statistical Package for Social Sciences (SPSS) software. Among 2,467 genotyped samples, Omicron was detected in 58.6% (n = 1445), Delta in 40.4% (n = 998) and undetermined/wildtype variant in 24 samples. The vaccination status of omicron-positive patients showed (49.7%; n = 718/1445) and Delta-positive patients (39.67%; n = 396/998) to be fully vaccinated. Of note, a high percentage 85% of breakthrough cases (n = 947) were identified among fully vaccinated individuals (n = 1114). Among them, 85.9% (n = 617/718) belonged to omicron and 83.3% (n = 330/396) to delta. Moreover, 76.7% (n = 855) of vaccinated individuals (n = 1114) received Sinopharm (n = 432) and Sinovac (n = 423) vaccines. The majority of breakthrough subjects who contracted Omicron were vaccinated with Sinopharm (93.0%, n = 256) and delta with Cansino (100%, n = 44). Individuals vaccinated with Sinovac showed the most frequent breakthrough cases for both Omicron and Delta variant between the 4th and 6th months (n = 278) after primary vaccination as compared to the 7th to 9th months (n = 24) category. While in case of Sinopharm, maximum breakthrough cases occurred between 7th to 9th months (n = 234) as compared to the 4th to 6th months (n = 120) after primary vaccination. Omicron and Delta breakthrough cases in men (n = 364 and 193) are more frequently seen than women (n = 253 and 138) respectively and breakthrough majority cases (n = 392) occurred in individuals aged 18-33 years. Breakthrough cases limiting monitoring in Pakistan impose a substantial constraint on policymakers' ability to take timely effective decisions. Since the current study consists of only a 2,467-genotyped sample, comprehensive data should be analyzed.

Genomic surveillance reveals the detection of SARS-CoV-2 delta, beta, and gamma VOCs during the third wave in Pakistan.

SARS-CoV-2 variants of concern (VOCs) have emerged worldwide and gained significant importance due to their high transmissibility and global spread, thus meriting close monitoring. In Pakistan, limited information is available on circulation of these variants as the alpha variant has been reported the main circulating lineage. The current study was designed to detect and explore the genomic diversity of SARS-CoV-2 lineages circulating during the third wave of the pandemic in the indigenous population. From May 01 to June 09, 2021, a total of 16 689 samples were tested using TaqPath™ COVID-19 kit for the presence of SARS-CoV-2. Overall, 2562 samples (15.4%) were COVID-19 positive. Out of these positive samples, 2124 (12.7%) did not show the spike gene amplification (spike gene target failure ([SGTF]), whereas 438 (2.6%) showed spike gene amplification (non-SGTF). A subset (n = 58/438) of non-SGTF samples were randomly selected for whole-genome sequencing. Among VOCs, 45% (n = 26/58) were delta, 46% (n = 27/58) were beta, and one was gamma variant. The delta variant cases were reported mainly from Islamabad (n = 15; 58%) followed by Rawalpindi and Azad Kashmir (n = 1; 4% each). Beta variant cases originated mainly from Karachi (n = 8; 30%) and Islamabad (n = 11; 41%) and the gamma variant case was reported in a traveler from Italy. The delta, beta, and gamma variants possessed lineage-specific spike mutations. Notably, two rare mutations (E484Q and L5F) were found in the delta variant. Furthermore, in the beta variant, two significant rare non-synonymous spike mutations (A879S and K444R) were also reported. High prevalence of beta and delta variants in local population may increase the number of cases in the near future and provides an early warning to national health authorities to take timely decisions and devise suitable interventions to contain a possible fourth wave.

Genomic Characterization of SARS-CoV2 from Peshawar Pakistan Using Next-Generation Sequencing.

This study aimed to characterize the whole genome of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) isolated from an oropharyngeal swab specimen of a Pashtun Pakistani patient using next-generation sequencing. Upon comparing the SARS-CoV2 genome to the reference genome, a total of 10 genetic variants were identified. Among the 10 genetic variants, 1 missense mutation (c.1139A > G, p.Lys292Glu) in the Open Reading Frame 1ab (ORF1ab) positioned at 112 in the non-structural protein 2 (NSP2) was found to be unique. Phylogenetic analysis (n = 84) revealed that the current SARS-CoV2 genome was closely clustered with 8 Pakistani strains belonging to Punjab, Federal Capital, Azad Jammu and Kashmir (AJK), and Khyber Pakhtunkhwa (KP). In addition, the current SARS-CoV2 genome was very similar to the genome of SARS-CoV2 reported from Guam, Taiwan, India, the USA, and France. Overall, this study reports a slight mismatch in the SARS-CoV2 genome, indicating the presence of a single unique missense mutation. However, phylogenetic analysis revealed that the current SARS-CoV2 genome was closely clustered with 8 other Pakistani strains.

Detection of SARS-CoV-2 using real-time polymerase chain reaction in different clinical specimens: A critical review.

Coronavirus disease 2019 (COVID-19) is a disease caused by a new strain of coronavirus named as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Globally, since the outbreak, more than seven million confirmed cases of COVID-19 have been reported. The rapid spread and increase in the number of new cases is due to person-to-person transmission. To further control its transmission, early laboratory diagnosis of both asymptomatic and symptomatic patients is crucial. Presently, the COVID-19 diagnosis of infected individuals is dependent on computed tomography scanning and real-time polymerase chain reaction (PCR). The latter is considered more sensitive and efficient for early diagnosis. In this review, general comparisons are made (cases, fatality rate, incubation period, clinical features, and reservoirs) and diagnostic laboratory procedures (specimens, extraction methods, and positive rates by real-time PCR) are compared between SARS, Middle East Respiratory Syndrome, and SARS-2. In total, 8982 SARS-2 suspected patients specimen data were retrieved, in which 40.9% (n = 3678) were detected as positive by real-time PCR. The specimen-wise high detection rate was observed from bronchoalveolar lavage, followed by saliva, nasal swabs, and sputum. As the COVID-19 cases are persistently increasing, the selection of appropriate specimens and laboratory assay would help in rapid and timely diagnosis.