scholarly journals SARS-CoV-2 Screening Test for Japanese Returnees From Wuhan, China, January 2020

2020 ◽  
Vol 7 (7) ◽  
Author(s):  
Satoshi Kutsuna ◽  
Tadaki Suzuki ◽  
Kayoko Hayakawa ◽  
Shinya Tsuzuki ◽  
Yusuke Asai ◽  
...  
Keyword(s):  
Chain Reaction ◽  
Important Data ◽  
Pcr Screening ◽  
Causative Microorganism ◽  
Medical Institutions ◽  
Polymerase Chain ◽  
Asymptomatic Infections ◽  
Asymptomatic Individuals ◽  
Pcr Test ◽  
Observation Period

Abstract Background Severe acute respiratory syndrome–related coronavirus 2 (SARS-CoV-2) was found to be the causative microorganism of coronavirus disease 2019 (COVID-19), which started to spread in Wuhan, China. This study was to evaluate the effectiveness of questionnaire, symptoms-based screening, and polymerase chain reaction (PCR) screening of returnees from COVID-19-endemic areas on a chartered flight, to examine the proportion of infected persons and the proportion of asymptomatic persons among infected persons who returned from Wuhan. Methods A retrospective cohort study was done in 7 tertiary medical institutions in Japan. A total of 566 Japanese who returned from Wuhan participated in the study. Results Overall, 11 of the 566 passengers had a positive SARS-CoV-2 PCR result for pharyngeal swabs and 6 were asymptomatic. Only fever differed between SARS-CoV-2-positive and -negative individuals (P < .043). Six of the 11 PCR-positive individuals were asymptomatic; 4 remained positive on day 10, and 1 asymptomatic person tested positive up to day 27. Two of the 11 were negative on the first PCR test and positive on the second. Conclusions Our results will be important insights on screening returnees from locked-down cities, as well as providing important data on the proportion of asymptomatic individuals infected with SARS-CoV-2. A 13-day observation period and a second round of PCR may be effective to screen patients, including asymptomatic infections.

scholarly journals What Is the Predictive Value of a Single Nasopharyngeal SARS-CoV-2 PCR Swab Test in a Patient With COVID-Like Symptoms and/or Significant COVID-19 Exposure?

2020 ◽  
Vol 7 (10) ◽  
Author(s):  
Blessen George ◽  
James McGee ◽  
Eileen Giangrasso ◽  
Sheila Finkelstein ◽  
Susan Wu ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Severe Acute Respiratory Syndrome ◽  
Predictive Value ◽  
Hospital Workers ◽  
Chain Reaction ◽  
Pcr Screening ◽  
Test Characteristics ◽  
Antibody Titers ◽  
Polymerase Chain ◽  
Pcr Test

Abstract Utilizing results of polymerase chain reaction (PCR) testing and subsequent antibody titers, we report on the test characteristics of a PCR screening test for severe acute respiratory syndrome coronavirus 2 among hospital workers. The PCR test was found to be 87% sensitive and 97% specific, with a positive predictive value of 0.98 and a negative predictive value of 0.80.

scholarly journals COVID-19 Pandemic Estimated End Date in Turkey

2021 ◽  
pp. 1-8
Author(s):  
Sare Merve Basaga ◽  
Zeynep Ture ◽  
Gamze Kalın Unver ◽  
Gökmen Zararsız ◽  
Orhan Yıldız ◽  
...  
Keyword(s):  
Interventional Procedure ◽  
Herd Immunity ◽  
Chain Reaction ◽  
Vaccination Programs ◽  
The Mean ◽  
Polymerase Chain ◽  
Asymptomatic Individuals ◽  
Two Peaks ◽  
Pcr Test ◽  
New Mutations

Background: Since the New Coronavirus Disease (COVID-19) can also be spread by asymptomatic individuals, identifying asymptomatic carriers is a key point in the fight against the COVID-19 pandemic. With this study, it was aimed to draw attention to the COVID-19 polymerase chain reaction (PCR) test positivity rate sent before the operation / interventional procedure in asymptomatic individuals and to determine an estimated time about the decay time of the pandemic. Methods: All patients over the age of 18 who were sent COVID-19 PCR test before the operation or interventional procedure between July 1 and October 31, 2020 were included in the study. The patients were divided into two groups according to the periods when the peak was experienced or not. Results: 1070 patients were included in the study. PCR positivity was detected in 55 (5.14%) of the patients. The mean case incidence rate was 0.76% (2/263) in the months when the study was conducted and there was no COVID-19 peak, and 6.57% (53/807) in the months when the peak was observed. These rates were taken as reference for the months with and without peak. The time to reach 67%, which is accepted as the herd immunity limit, was calculated by adding 6.57% to the months corresponding to peak periods with 20-day periods starting from April 1, and the rate of 0.76% to the other months. Since there were two peaks after April 2020, the mass immunity rate reached until today has been calculated . If no COVID-19 peak occurs since this date, the possible pandemic attenuation time was determined as March 2022, and if the only peak occurs, May 2021. Conclusions: The incidence fluctuates with the restrictions, the risk of re-infection, the virüs being open to new mutations, and the initiation of vaccination programs make it difficult to predict the pandemic attenuation time.

scholarly journals The Issue of Recurrently Positive Patients Who Recovered From COVID-19 According to the Current Discharge Criteria: Investigation of Patients from Multiple Medical Institutions in Wuhan, China

2020 ◽  
Vol 222 (11) ◽  
pp. 1784-1788 ◽  
Author(s):  
You Zou ◽  
Bin-Ru Wang ◽  
Liu Sun ◽  
Shan Xu ◽  
Yong-Gang Kong ◽  
...  
Keyword(s):  
Test Results ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Current Discharge ◽  
Negative Results ◽  
Medical Institutions ◽  
Polymerase Chain ◽  
Discharge Criteria ◽  
Test Result ◽  
Pcr Test

Abstract The current discharge criteria for COVID-19 require that patients have 2 consecutive negative results for reverse transcription polymerase chain reaction (RT-PCR) detection. Here, we observed that recurrent positive RT-PCR test results in patients with 3 consecutive negative results (5.4%) were significantly decreased compared with those in patients with 2 consecutive negative results (20.6%); such patients reported positive RT-PCR test results within 1 to 12 days after meeting the discharge criteria. These results confirmed that many recovered patients could show a positive RT-PCR test result, and most of these patients could be identified by an additional RT-PCR test prior to discharge.

Death and COVID-19 Anxiety in Home-Quarantined Individuals Aged 65 and Over During the Pandemic

2021 ◽  
pp. 003022282110598
Author(s):  
Hümeyra Aslaner ◽  
Betül Özen ◽  
Zeliha K. Erten ◽  
Mebrure Beyza Gökçek
Keyword(s):  
Polymerase Chain Reaction ◽  
Death Anxiety ◽  
Short Form ◽  
Anxiety Score ◽  
Test Results ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Test Result ◽  
Pcr Test

Urgent measures were taken for those at the age of 65 and over who were at the risk group all over the world due to the COVID-19 pandemic. It is known that many individuals at the age of 65 and over have experienced anxiety due to the uncertainties. This study aimed to determine the anxiety and death anxiety in individuals aged 65 and over who were isolation at home due to being diagnosed with COVID-19 or being in contact during the pandemic process. The study is descriptive and cross-sectional. It was performed with 656 home-quarantined individuals aged between 65–80 years with positive or negative real-time polymerase chain reaction (RT-PCR) test result. A form including questions about the death anxiety and the Coronavirus Anxiety Scale Short Form prepared by the researchers were administered to the individuals by phone call. Of the participants, 49.5% were male. Median COVID-19 anxiety score was 4 (0–18). Anxiety scores of the male and female participants were similar. Participants with negative polymerase chain reaction (PCR) results and those with death anxiety had higher COVID anxiety scores. Death anxiety has increased by 1.661 times in male gender, 1.983 times in RT-PCR positivity and 0.146 times in the presence of symptoms. Individuals with positive COVID-19 test results or those aged 65 and over who had death anxiety and negative COVID-19 test result but who were in home-isolation due to being a contact had higher anxiety score. For this reason, those with death anxiety can be supported in line with their religious beliefs to reduce anxiety. Those with negative PCR test results in quarantine can be adequately informed about the COVID-19.

scholarly journals Estimation of the probability of reinfection with COVID-19 coronavirus by the SEIRUS model

2020 ◽  
Author(s):  
Victor Alexander Okhuese
Keyword(s):  
Recovery Rate ◽  
Death Rate ◽  
Basic Reproductive Number ◽  
Reproductive Number ◽  
Chain Reaction ◽  
Health Community ◽  
Polymerase Chain ◽  
Model Equations ◽  
Disease Free ◽  
Pcr Test

AbstractWith sensitivity of the Polymerase Chain Reaction (PCR) test used to detect the presence of the virus in the human host, the global health community has been able to record a great number of recovered population. Therefore, in a bid to answer a burning question of reinfection in the recovered class, the model equations which exhibits the disease-free equilibrium (E0) state for COVID-19 coronavirus was developed in this study and was discovered to both exist as well as satisfy the criteria for a locally or globally asymptotic stability with a basic reproductive number R0 = 0 for and endemic situation. Hence, there is a chance of no secondary reinfections from the recovered population as the rate of incidence of the recovered population vanishes, that is, B = 0.Furthermore, numerical simulations were carried to complement the analytical results in investigating the effect of the implementation of quarantine and observatory procedures has on the projection of the further spread of the virus globally. Result shows that the proportion of infected population in the absence of curative vaccination will continue to grow globally meanwhile the recovery rate will continue slowly which therefore means that the ratio of infection to recovery rate will determine the death rate that is recorded globally and most significant for this study is the rate of reinfection by the recovered population which will decline to zero over time as the virus is cleared clinically from the system of the recovered class.

scholarly journals Streptococcus agalactiae mastitis of bovine detection by Polymerase Chain Reaction (PCR) test in AL-Diwanyia province

2013 ◽  
Vol 12 (2) ◽  
pp. 101
Author(s):  
Gh. K. A. Al-kuzaay ◽  
Q. H. Kshash
Keyword(s):  
Polymerase Chain Reaction ◽  
Streptococcus Agalactiae ◽  
Specific Primer ◽  
Chain Reaction ◽  
Pcr Assay ◽  
Milk Samples ◽  
Bacteriological Testing ◽  
Polymerase Chain ◽  
Pcr Test

This study was conducted for exam 348 milk samples from (clinically mastitic and other healthy cows) in many areas in AL-Diwanyia province by using CMT and bacteriological testing , which appeared that (64.9%) as percentage of mastitis ( clinically 15.9% , subclinically 84.0% ) Streptococcus agalactiae mastitis 13.2% ( 26.6% clinically , 73.3 % subclinicaly) diagnose by PCR assay by using specific primer (16SrRNA). Streptococcus agalactiae (30 isolates) after classical methods applied for streptococcus agalactiae identification (86 isolates).

scholarly journals Evaluating the bacterial culture technique by Polymerase chain reaction for the diagnosis of Brucella abortus in milk of cows suspected with brucellosis.

2016 ◽  
Vol 40 (1) ◽  
pp. 5-8
Author(s):  
Bashar Sadeq Noomy
Keyword(s):  
Polymerase Chain Reaction ◽  
Brucella Abortus ◽  
Bacterial Culture ◽  
Culture Technique ◽  
Test Results ◽  
Chain Reaction ◽  
Culture Techniques ◽  
Milk Samples ◽  
Polymerase Chain ◽  
Pcr Test

      The aim of this study is to determine the sensitivity of bacterial culture technique in the detection of Brucella abortus in milk samples of aborted cows. Sixty samples of milk were collected from aborted cows during a period which did not exceed two months after the abortion. All of them were positive for rose bengal test. Results showed that Brucella abortus was isolated from 7 out of 60 (11.6%) from the milk of aborted cows, while PCR test showed that 32 out of 60 (53.3%) milk sample contained Brucella abortus. The specificity of culture techniques was 10%, but its sensitivity was only 21.8%. Beside the cautions in dealing with live Brucella abortus (as culture), it is also less sensitive than PCR, though it is better to use PCR technique in the diagnosis of brucellosis in aborted cows milk.

scholarly journals Descriptive epidemiology of coronavirus disease 2019 in Nigeria, 27 February–6 June 2020

2020 ◽  
Vol 148 ◽  
Author(s):  
K. O. Elimian ◽  
C. L. Ochu ◽  
E. Ilori ◽  
J. Oladejo ◽  
E. Igumbor ◽  
...  
Keyword(s):  
Health Planning ◽  
Case Fatality ◽  
National Surveillance ◽  
Descriptive Epidemiology ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Response Strategies ◽  
Polymerase Chain ◽  
Insight Into ◽  
Pcr Test

Abstract The objective of this study was to describe the epidemiology of COVID-19 in Nigeria with a view of generating evidence to enhance planning and response strategies. A national surveillance dataset between 27 February and 6 June 2020 was retrospectively analysed, with confirmatory testing for COVID-19 done by real-time polymerase chain reaction (RT-PCR). The primary outcomes were cumulative incidence (CI) and case fatality (CF). A total of 40 926 persons (67% of total 60 839) had complete records of RT-PCR test across 35 states and the Federal Capital Territory, 12 289 (30.0%) of whom were confirmed COVID-19 cases. Of those confirmed cases, 3467 (28.2%) had complete records of clinical outcome (alive or dead), 342 (9.9%) of which died. The overall CI and CF were 5.6 per 100 000 population and 2.8%, respectively. The highest proportion of COVID-19 cases and deaths were recorded in persons aged 31–40 years (25.5%) and 61–70 years (26.6%), respectively; and males accounted for a higher proportion of confirmed cases (65.8%) and deaths (79.0%). Sixty-six per cent of confirmed COVID-19 cases were asymptomatic at diagnosis. In conclusion, this paper has provided an insight into the early epidemiology of COVID-19 in Nigeria, which could be useful for contextualising public health planning.

scholarly journals Diagnostic accuracy of initial chest radiograph compared to SARS-CoV-2 PCR in patients with suspected COVID-19

BJR|Open ◽  
2020 ◽  
Vol 2 (1) ◽  
pp. 20200034
Author(s):  
Maria Tsakok ◽  
Robert Shaw ◽  
Andrew Murchison ◽  
Sarim Ather ◽  
Cheng Xie ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Chest Radiograph ◽  
Hospital Setting ◽  
Clinical Suspicion ◽  
Reference Test ◽  
Chain Reaction ◽  
Total Cohort ◽  
Initial Cohort ◽  
Polymerase Chain ◽  
Pcr Test

Objective: The chest radiograph (CXR) is the predominant imaging investigation being used to triage patients prior to either performing a SARS-CoV-2 polymerase chain reaction (PCR) test or a diagnostic CT scan, but there are limited studies that assess the diagnostic accuracy of CXRs in COVID-19. To determine the accuracy of CXR diagnosis of COVID-19 compared with PCR in patients presenting with a clinical suspicion of COVID-19. Methods and materials: The CXR reports of 569 consecutive patients with a clinical suspicion of COVID-19 were reviewed, blinded to the PCR result and classified into the following categories: normal, indeterminate for COVID-19, classic/probable COVID-19, non-COVID-19 pathology, and not specified. Severity reporting and reporter expertise were documented. The subset of this cohort that had CXR and PCR within 3 days of each other were included for further analysis for diagnostic accuracy. Results: Classic/probable COVID-19 was reported in 29% (166/569) of the initial cohort. 67% (382/569) had PCR tests. 344 patients had CXR and PCR within 3 days of each other. Compared to PCR as the reference test, initial CXR had a 61% sensitivity and 76% specificity in the diagnosis of COVID-19. Conclusion: Initial CXR is useful as a triage tool with a sensitivity of 61% and specificity of 76% in the diagnosis of COVID-19 in a hospital setting. Advances in knowledge: . Diagnostic accuracy does not differ significantly between specialist thoracic radiologists and general radiologists including trainees following training. There was a 40% prevalence of PCR positive disease in the cohort of patients (n = 344) having CXR and PCR within 3 days of each other. Classic/probable COVID-19 was reported in 29% of total cohort of patients presenting with clinical suspicion of COVID-19 (n = 569). Initial CXR is useful as a triage tool with a sensitivity of 61% and specificity of 76% in the diagnosis of COVID-19 in a hospital setting

scholarly journals Performance of a Commercial Polymerase Chain Reaction Test for EndocervicalChlamydia trachomatisInfection in a University Hospital Population

1998 ◽  
Vol 6 (5) ◽  
pp. 224-229
Author(s):  
C. H. Livengood III ◽  
K. A. Boggess ◽  
J. W. Wrenn ◽  
A. P. Murtha
Keyword(s):  
Polymerase Chain Reaction ◽  
Polymerase Chain Reaction Test ◽  
Laboratory Evaluation ◽  
Clinical Samples ◽  
Chain Reaction ◽  
Predictive Values ◽  
Target Dna ◽  
Wide Range ◽  
Polymerase Chain ◽  
Pcr Test

Objectives:To examine the accuracy of a commercial polymerase chain reaction (PCR) test (Amplicor CTR, Roche Diagnostic Systems, Branchburg NJ) for identification of endocervical chlamydial infections through both laboratory evaluation and among a diverse teaching hospital patient population.Methods:Testing of reliable threshold inocula and reproducibility were carried out using laboratory stock organisms. Paired endocervical samples from patients with a wide range of indications were tested by PCR and an established culture procedure, and discrepant pairs were further analyzed to determine true results.Results:Laboratory evaluation suggested that one copy of target DNA from a viable organism consistently yielded a positive result, and test reproducibility was very good, with an overall coefficient of variation of 15%. Compared to true results in 1,588 paired clinical samples from 1,489 women with a 10% prevalence of infection, the PCR test and culture yielded respective sensitivities of 87.4% and 78.0%, and negative predictive values of 98.6% and 97.6%. Specificity and positive predictive value for both tests were 100%. Cost per specimen was nearly identical at $18.84 and $18.88 respectively. Polymerase inhibitors and organisms lacking target DNA were not found in false-negative PCR samples.Conclusion:This commercial PCR test is accurate, cost-competitive, and much faster than culture for diagnosis of endocervical chlamydia infections in our population of intermediate prevalence of chlamydial infection.

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