ABSTRACT
Cytomegalovirus (CMV) is the most common cause of congenital viral infections. Women seropositive for CMV prior to pregnancy can develop a non-primary CMV infection. Here, we present a case of first trimester pregnancy loss during active SARS-CoV-2 infection. There was no evidence of SARS-CoV-2 RNA in placenta and fetal tissue, but there was presence of congenital cytomegalovirus infection by nested PCR. To the best of our knowledge, this is the first report demonstrating association of early congenital CMV infection due to reactivation and fetal demise in a SARS-CoV-2 positive woman with fetal trisomy 21.
Subject(s)
COVID-19 , Cytomegalovirus Infections , Down Syndrome , Pregnancy , Female , Humans , SARS-CoV-2 , Cytomegalovirus , Pregnancy Trimester, First , RNA, Viral , Fetus , Fetal DeathABSTRACT
BACKGROUND: India bears the second largest burden of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. A multitude of reverse transcription polymerase chain reaction (RT-PCR) detection assays with disparate gene targets, including automated high-throughput platforms, are available. Varying concordance and interpretation of diagnostic results in this setting can result in significant reporting delays, leading to suboptimal disease management. This article reports the development of a novel ORF1a-based SARS-CoV-2 RT-PCR assay - Viroselect - that shows high concordance with conventional assays and the ability to resolve inconclusive results generated during the peak of the epidemic in Mumbai, India. METHODS: A unique target region within SARS-CoV-2 ORF1a - the non-structural protein 3 (nsp3) region - was used to design and develop the assay. This hypervariable region (1923-3956) between SARS-CoV-2, SARS-CoV-1 and Middle East respiratory syndrome coronavirus was utilized to design the primers and probes for the RT-PCR assay. The concordance of this assay with commonly used emergency use authorization (US Food and Drug Administration) manual kits and an automated high-throughput testing platform was evaluated. Further, a retrospective analysis was carried out using Viroselect on samples reported as 'inconclusive' between April and October 2020. RESULTS: In total, 701 samples were tested. Concordance analysis of 477 samples demonstrated high overall agreement of Viroselect with both manual (87.6%) and automated (84.7%) assays. Also, in the retrospective analysis of 224 additional samples reported as 'inconclusive', Viroselect was able to resolve 100% (19/19) and 93.7% (192/205) of samples which had inconclusive results on manual and automated high-throughput platforms, respectively. CONCLUSION: Viroselect had high concordance with conventional assays, both manual and automated, and has potential to resolve inconclusive samples.
Subject(s)
COVID-19 Testing/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , Viral Proteins/genetics , Humans , Limit of Detection , Polyproteins/genetics , Retrospective Studies , SARS-CoV-2/isolation & purificationABSTRACT
There is a need for understanding and establishment of the most appropriate testing algorithm for COVID-19 diagnosis in asymptomatic high-risk groups. Here, we present a retrospective analysis of RT-PCR results obtained from 412 cases tested negative for coronavirus disease 2019 (COVID-19) by rapid antigen testing method. Among 178 (43.2%) asymptomatic individuals, 44.9% of the high risk contacts, 12.2% of police custody individuals, 22.22% of the pregnant women and 33.33% of individuals hospitalised for preoperative or other medical conditions showed RT-PCR positivity. Our results suggest a need for focussed and intensive (multi-modality) testing in groups at high risk for SARS-CoV-2 infection.
Subject(s)
COVID-19 Testing , COVID-19 , COVID-19/diagnosis , COVID-19 Nucleic Acid Testing , COVID-19 Testing/methods , Disease Management , Female , Humans , India , Pregnancy , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and SpecificityABSTRACT
In this current pandemic of coronavirus disease 2019 (COVID-19), prompt interventions in terms of early detection and clinical management along with isolation of positive cases is of utmost importance. This helps to limit not only the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections but also the morbidity and mortality associated with it. Different strategies for screening of COVID-19 in containment zones and non-containment areas include testing of symptomatic patients and their contacts in fever clinics, hospital-based testing, testing on demand and population-based screening. The choice of tests like reverse-transcription polymerase chain reaction (RT-PCR), rapid antigen testing (RAT) or antibody test depends upon these strategies and also the turnaround time. Currently, RT-PCR is considered the gold standard for COVID-19 detection. This commentary provides the insights and experiences on COVID-19 diagnosis by RT-PCR. The utility of this test is limited by several false positive, false negative and inconclusive results at early stages of infection, scarcity of reagents and lack of well-equipped labs including trained staff. Moreover, appropriate sample collection and transport, standard laboratory protocols, stringent quality control norms, good quality RNA extraction kits, PCR kits with suitable primers can help in improving accuracy of the test results. A careful assessment of clinical, radiological and molecular findings is required for identifying potential cases of COVID-19.