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| [[File:MERS-CoV Particles (8414774264).jpg|thumb|Colorized transmission electron micrograph showing particles of the Middle East respiratory syndrome coronavirus that emerged in 2012]]Unlike SARS, Middle East respiratory syndrome, or MERS, continues to appear in the human population. Since its appearance in 2012, several thousand laboratory-confirmed cases of MERS have been reported to the WHO.<ref name="Bernard-StoecklinCompar19">{{cite journal |title=Comparative Analysis of Eleven Healthcare-Associated Outbreaks of Middle East Respiratory Syndrome Coronavirus (Mers-Cov) from 2015 to 2017 |journal=Scientific Reports |author=Bernard-Stoecklin, S.; Nikolay, B.; Assiri, A. et al. |volume=9 |at=7385 |year=2019 |doi=10.1038/s41598-019-43586-9 |pmid=31089148 |pmc=PMC6517387}}</ref> The virus MERS-CoV is believed to have originated from bats, which at some unknown point spread to Dromedary camels. Approximately 55 percent of MERS-CoV infections have come from direct contact with such camels, though it's not entirely clear how the rest of known cases have been caused<ref name="BanerjeeBats19">{{cite journal |title=Bats and Coronaviruses |journal=Viruses |author=Banerjee, A.; Kulcsar, K.; Misra, V. et al. |volume=11 |issue=1 |at=E41 |year=2019 |doi=10.3390/v11010041 |pmid=30634396 |pmc=PMC6356540}}</ref> (Alshukairi ''et al.'' suggest asymptomatic or mildly symptomatic camel workers may serve as a possible transmission source<ref name="AlshukairiHigh18">{{cite journal |title=High Prevalence of MERS-CoV Infection in Camel Workers in Saudi Arabia |journal=mBio |author=Alshukairi, A.N.; Zheng, J.; Zhao, J. et al. |volume=9 |issue=5 |pages=e01985-18 |year=2018 |doi=10.1128/mBio.01985-18 |pmid=30377284 |pmc=PMC6212820}}</ref>). The following sample collection and test procedures have evolved from working with the MERS-CoV virus (note that this is only a summary; consult the cited literature directly for full details)<ref name="CDCLabTestMERS19">{{cite web |url=https://www.cdc.gov/coronavirus/mers/lab/lab-testing.html |title=CDC Laboratory Testing for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) |author=Centers for Disease Control and Prevention |publisher=Centers for Disease Control and Prevention |date=02 August 2019 |accessdate=04 April 2020}}</ref><ref name="CDCInterimMERS19">{{cite web |url=https://www.cdc.gov/coronavirus/mers/guidelines-clinical-specimens.html |title=Interim Guidelines for Collecting, Handling, and Testing Clinical Specimens from Persons Under Investigation (PUIs) for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) – Version 2.1 |author=Centers for Disease Control and Prevention |publisher=Centers for Disease Control and Prevention |date=02 August 2019 |accessdate=04 April 2020}}</ref><ref name="WHOLabMERS18">{{cite web |url=https://www.who.int/csr/disease/coronavirus_infections/mers-laboratory-testing/en/ |title=Laboratory testing for Middle East Respiratory Syndrome Coronavirus: Interim guidance |work=WHO/MERS/LAB/15.1/Rev1/2018 |author=World Health Organization |publisher=World Health Organization |date=January 2018 |accessdate=04 April 2020}}</ref><ref name="Al-AbdelyMiddle19">{{cite journal |title=Middle East Respiratory Syndrome Coronavirus Infection Dynamics and Antibody Responses among Clinically Diverse Patients, Saudi Arabia |journal=Emerging Infectious Diseases |author=Al-Abdely, H.M.; Midgley, C.M.; Alkhamis, A.M. et al. |volume=25 |issue=4 |pages=753-766 |year=2019 |doi=10.3201/eid2504.181595}}</ref><ref name="Kelly-CirinoAnUpdated19">{{cite journal |title=An updated roadmap for MERS-CoV research and product development: focus on diagnostics |journal=BMJ Global Health |author=Kelly-Cirino, C.; Mazzola, L.T.; Chua, A. et al. |volume=4 |issue=Suppl. 2 |at=e001105 |year=2019 |doi=10.1136/bmjgh-2018-001105 |pmid=30815285 |pmc=PMC6361340}}</ref>:
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| | |title=Introduction to Quality and Quality Management Systems |
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| * Determine that the patient is indicating clinical and/or epidemiological evidence of MERS (meets case definitions). "Testing for other respiratory pathogens using routinely available laboratory procedures, as recommended in local management guidelines for community-acquired pneumonia, should also be performed but should not delay testing for MERS-CoV."<ref name="WHOLabMERS18" />
| | ==''Introduction to Quality and Quality Management Systems''== |
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| | | type = content |
| | | style = width: 500px; |
| | | text = This book should not be considered complete until this message box has been removed. This is a work in progress. |
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| | The goal of this short volume is to act as an introduction to the quality management system. It collects several articles related to quality, quality management, and associated systems. |
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| * Collect at a minimum both lower respiratory and upper respiratory tract samples. Lower respiratory tract specimens are typically the most revealing, as they have been shown to contain the highest viral load (due to the expression of the virus's cellular receptor DPP4 in the lower respiratory system). Bronchoalveolar lavage, tracheal aspiration, or a pleural tap can be used to collect specimens from the lower respiratory tract. (Sputum can also be collected.) Upper respiratory tract specimens (in this case, both a nasopharyngeal and an oropharyngeal swab are recommended) are also valuable in diagnosis, though extra care should be taken to ensure nasopharyngeal swabs gather secretions from the [[Pharynx#Nasopharynx|nasopharynx]] and not just the nostril. Nasopharyngeal aspiration is also an acceptable sample collection method for the upper respiratory tract.
| | ;1. What is quality? |
| | :''Key terms'' |
| | :[[Quality (business)|Quality]] |
| | :[[Quality assurance]] |
| | :[[Quality control]] |
| | :''The rest'' |
| | :[[Data quality]] |
| | :[[Information quality]] |
| | :[[Nonconformity (quality)|Nonconformity]] |
| | :[[Service quality]] |
| | ;2. Processes and improvement |
| | :[[Business process]] |
| | :[[Process capability]] |
| | :[[Risk management]] |
| | :[[Workflow]] |
| | ;3. Mechanisms for quality |
| | :[[Acceptance testing]] |
| | :[[Conformance testing]] |
| | :[[Clinical quality management system]] |
| | :[[Continual improvement process]] |
| | :[[Corrective and preventive action]] |
| | :[[Good manufacturing practice]] |
| | :[[Malcolm Baldrige National Quality Improvement Act of 1987]] |
| | :[[Quality management]] |
| | :[[Quality management system]] |
| | :[[Total quality management]] |
| | ;4. Quality standards |
| | :[[ISO 9000]] |
| | :[[ISO 13485]] |
| | :[[ISO 14000|ISO 14001]] |
| | :[[ISO 15189]] |
| | :[[ISO/IEC 17025]] |
| | :[[ISO/TS 16949]] |
| | ;5. Quality in software |
| | :[[Software quality]] |
| | :[[Software quality assurance]] |
| | :[[Software quality management]] |
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| :Regarding serum specimens, slight differences in guidance appear between WHO guidance and CDC guidance. The WHO appears to differentiate between symptomatic and asymptomatic patient testing, whereas the U.S. CDC seems to only indirectly differentiate the two. The WHO suggests if testing symptomatic patients, stick with lower and upper respiratory tract specimens, which will be tested using nucleic acid amplification (molecular) testing (NAAT). Serological testing of serum specimens should be used for symptomatic patients "only if NAAT is not available."<ref name="WHOLabMERS18" /> If this is the case, the WHO recommends paired samples, one collected within the first week of illness and the second about three to four weeks later. For asymptomatic patients in high-contact outbreak scenarios, the WHO recommends all three sample types (with respiratory samples taken preferably within 14 days of last documented contact).
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| :The current CDC guidance differentiates between molecular testing for active infections and serology for previous infections. The CDC adds that "MERS-CoV serology tests are for surveillance or investigational purposes and not for diagnostic purposes."<ref name="CDCLabTestMERS19" /> Whether or not to collect a serum specimen in MERS diagnostics may depend on the assay used, however. For example, the CDC, in its Version 2.1 guidance, indicates that testing using the CDC MERS rRT-PCR assay requires collection of serum in addition to upper and lower respiratory tract specimens. For that specific assay, the CDC differentiates between patients who've had symptom onset less than 14 days prior and those who've had it 14 days or later: if prior, serology is for the rRT-PCR test, and if later, serology is for antibody testing. In either case, 200 µL of serum is required.
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| * Conduct testing. NAAT methods like real-time reverse-transcription polymerase chain reaction (rRT-PCR) assays have been the most common tool for diagnosing MERS-CoV infection due to their high sensitivity. According to late 2018 research by Kelly-Cirino ''et al.'', at least 11 commercial single assay and five commercial multiplex assay kits are available (see [https://gh.bmj.com/content/bmjgh/4/Suppl_2/e001105/DC1/embed/inline-supplementary-material-1.pdf Table S1], a PDF file, from their highly relevant paper), perhaps more as of April 2020. Serological antibody detection is performed using ELISA, [[Immunofluorescence#Secondary (indirect)|indirect immunofluorescence]] (IIF), and [[Neutralisation (immunology)|microneutralization]].
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| * Confirm the results. Laboratory confirmation of MERS-CoV infection is the same for both the WHO and the CDC: one of either a validated NAAT test providing a positive result for at least two different genomic targets, or a validated NAAT test providing a positive result for a specific genomic target along with sequencing confirmation of a separate genomic target. Persons under investigation who receive one negative NAAT result on a recommended specimen are considered to be negative for active MERS-CoV infection. The laboratory should consider testing additional specimens after the first negative. The CDC considers known MERS patients to be negative for active MERS-CoV infection after two consecutive negative NAAT tests on all specimens. The WHO adds: "A patient with a positive NAAT result for a single specific target without further testing but with a history of potential exposure and consistent clinical signs is considered a probable case."<ref name="WHOLabMERS18" /> The WHO also has additional guidance on using serology for confirming MERS-CoV infection for purposes of reporting under the International Health Regulations.
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| * Report using national reporting requirements. More broadly, state or local health departments should receive details about received specimens to be tested for MERS-CoV, even before testing begins. Regardless of result, the final positive or negative laboratory confirmation should also be reported to national authorities. If the infection becomes widespread, updates for each new confirmed case or suspected positive should also be made.
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| ==References==
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| {{Reflist|colwidth=30em}}
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