Clinical evaluation of real-time PCR assays for rapid diagnosis of SARS coronavirus during outbreak and post-epidemic periods

Testing of Patients and Support Persons for Coronavirus Disease 2019 (COVID-19) Infection Before Scheduled Deliveries

OBJECTIVE

To evaluate the rate of coronavirus disease 2019 (COVID-19) infection with the use of universal testing in our obstetric population presenting for scheduled deliveries, as well as the concordance or discordance rate among their support persons during the initial 2-week period of testing. Additionally, we assessed the utility of a screening tool in predicting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing results in our cohort.

METHODS

This was an observational study in which all women who were scheduled for a planned delivery within the Mount Sinai Health system from April 4 to April 15, 2020, were contacted and provided with an appointment for themselves as well as their support persons to undergo COVID-19 testing 1 day before their scheduled delivery. Both the patients and the support persons were administered a standardized screen specific for COVID-19 infection by telephone interview. Those support persons who screened positive were not permitted to attend the birth. All patients and screen-negative support persons underwent SARS-CoV-2 testing.

RESULTS

During the study period, 155 patients and 146 support persons underwent SARS-CoV-2 testing. The prevalence of asymptomatic COVID-19 infection was 15.5% (CI 9.8-21.2%) and 9.6% (CI 4.8-14.4%) among patients and support persons, respectively. The rate of discordance among tested pairs was 7.5%. Among patients with COVID-19 infection, 58% of their support persons also had infection; in patients without infection, fewer than 3.0% of their support persons had infection.

CONCLUSION

We found that more than 15% of asymptomatic maternity patients tested positive for SARS-CoV-2 infection despite having screened negative with the use of a telephone screening tool. Additionally, 58% of their asymptomatic, screen-negative support persons also tested positive for SARS-CoV-2 infection. Alternatively, testing of the support persons of women who had tested negative for COVID-19 infection had a low yield for positive results. This has important implications for obstetric and newborn care practices as well as for health care professionals.

An infant with coronavirus disease 2019 in China: A case report

RATIONALE

In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) occurred in Wuhan, China. The initial epidemiological investigations showed that COVID-19 occurred more likely in adults, with patients younger than 10 years old accounting for less than 1% of the total number of confirmed cases, and infant infections were more rare. In our case, we present an infant who was only 35 days old when he was tested positive for COVID-19.

PATIENT CONCERNS

In this report, a 35 day-old male infant with atypical symptoms had close contact with 2 confirmed patients of COVID-19 who were his grandmother and mother.

DIAGNOSIS

The patient was diagnosed as COVID-19 after his oropharyngeal swab tested positive for severe acute respiratory syndrome coronavirus 2 by reverse transcription-polymerase chain reaction assay.

INTERVENTIONS

The therapeutic schedule included aerosol inhalation of recombinant human interferon α-2b and supportive therapy.

OUTCOMES

Two consecutive (1 day apart) oropharyngeal swabs tested negative for severe acute respiratory syndrome coronavirus 2; then, the patient was discharged on February 27, 2020.

LESSONS

Strengthening infants' virus screening in families with infected kins is important for early diagnosis, isolation, and treatment when symptoms are atypical. The infectivity of infants with mild or asymptomatic COVID-19 should not be ignored because this may be a source of transmission in the community.

Severe acute respiratory syndrome (SARS) and coronavirus disease-2019 (COVID-19): From causes to preventions in Hong Kong

Hong Kong has been recently attacked by the coronavirus disease-2019 (COVID-19). In late January 2020, it's shown a steadily increasing trend of confirmed cases. There is a 257 in total infected cases confirmed including 4 deaths until 20th of March 2020. To prevent further outbreak of COVID-19, this article discusses the current understanding of COVID-19 and compares with the outbreak of SARS-CoV-2 in 2003 of Hong Kong from the causes, transmission, symptoms, diagnosis, treatments and preventions to study for an applicable measurement to control COVID-19.

Severe acute respiratory syndrome coronavirus as an agent of emerging and reemerging infection

Before the emergence of severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) in 2003, only 12 other animal or human coronaviruses were known. The discovery of this virus was soon followed by the discovery of the civet and bat SARS-CoV and the human coronaviruses NL63 and HKU1. Surveillance of coronaviruses in many animal species has increased the number on the list of coronaviruses to at least 36. The explosive nature of the first SARS epidemic, the high mortality, its transient reemergence a year later, and economic disruptions led to a rush on research of the epidemiological, clinical, pathological, immunological, virological, and other basic scientific aspects of the virus and the disease. This research resulted in over 4,000 publications, only some of the most representative works of which could be reviewed in this article. The marked increase in the understanding of the virus and the disease within such a short time has allowed the development of diagnostic tests, animal models, antivirals, vaccines, and epidemiological and infection control measures, which could prove to be useful in randomized control trials if SARS should return. The findings that horseshoe bats are the natural reservoir for SARS-CoV-like virus and that civets are the amplification host highlight the importance of wildlife and biosecurity in farms and wet markets, which can serve as the source and amplification centers for emerging infections.

Evaluation of a multiplexed PCR assay for detection of respiratory viral pathogens in a public health laboratory setting

There are numerous viral and bacterial causes of respiratory disease. To enable rapid and sensitive detection of even the most prevalent causes, there is a need for more-simplified testing systems that enable researchers and clinicians to perform multiplexed molecular diagnostics quickly and easily. To this end, a new multiplexed molecular test called the MultiCode-PLx respiratory virus panel (PLx-RVP) was developed and then implemented in a public health laboratory setting. A total of 687 respiratory samples were analyzed for the presence of 17 viruses that commonly cause respiratory disease. As a comparator, the samples were also tested using a standard testing algorithm that included the use of a real-time influenza virus A and B reverse transcription-PCR test and routine viral culture identification. The standard testing algorithm identified 503 (73%) samples as positive and 184 as negative. Analyzing the same 687 samples, the PLx-RVP assay detected one or more targets in 528 (77%) samples and found 159 samples negative for all targets. There were 25 discordant results between the two systems; 14 samples were positive for viruses not routinely tested for by the Wisconsin State Laboratory of Hygiene, and 13 of these were confirmed by real-time PCR. When the results of the standard testing algorithm were considered "true positives," the PLx-RVP assay showed an overall sensitivity of 99% and an overall specificity of 87%. In total, the PLx-RVP assay detected an additional 40 viral infections, of which 11 were mixed infections.

Using patient-collected clinical samples and sera to detect and quantify the severe acute respiratory syndrome coronavirus (SARS-CoV)

Background

Severe acute respiratory syndrome (SARS) caused a large outbreak of pneumonia in Beijing, China, in 2003. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect and quantify SARS-CoV in 934 sera and self-collected throat washes and fecal samples from 271 patients with laboratory-confirmed SARS managed at a single institution.

Results

SARS-CoV detection rates in sera were highest in the first 9 days of illness, whereas detection was highest in throat washes 5–14 days after onset of symptoms. The highest SARS-CoV RT-PCR rates (70.4–86.3%) and viral loads (log₁₀ 4.5–6.1) were seen in fecal samples collected 2–4 weeks after the onset of clinical illness. Fecal samples were frequently SARS-CoV RT-PCR positive beyond 40 days, and occasional sera still had SARS-CoV detected after 3 weeks of illness.

Conclusion

In the context of an extensive outbreak with major pressure on hospital resources, patient self-collected samples are an alternative to nasopharyngeal aspirates for laboratory confirmation of SARS-CoV infection.

Severe acute respiratory syndrome in children

BACKGROUND

Severe acute respiratory syndrome (SARS) is a febrile, respiratory tract illness caused by infection with the newly identified SARS-associated coronavirus. A notable feature of the 2003 global SARS outbreak was the relative paucity of cases reported among children. We reviewed the epidemiologic and clinical features of SARS in children and discuss implications of these findings for diagnosis, treatment and prevention of SARS.

METHODS

We performed a literature search to identify reports of pediatric (younger than 18 years of age) patients meeting the World Health Organization case definitions for SARS and abstracted relevant clinical and epidemiologic information.

RESULTS

We identified 6 case series reporting 135 pediatric SARS patients (80 laboratory-confirmed, 27 probable and 28 suspect) from Canada, Hong Kong, Taiwan and Singapore. Among laboratory-confirmed and probable SARS cases, the most common symptoms included fever (98%), cough (60%) and nausea or vomiting (41%); 97% had radiographic abnormalities. The clinical presentation of SARS in patients older than 12 years of age was similar to that in adults. However, patients 12 years of age or younger had milder disease and were less likely than older children to be admitted to an intensive care unit, receive supplemental oxygen or be treated with methylprednisolone. No deaths were reported among children or adolescents with SARS, and at 6 months after illness only mild residual changes were reported in exercise tolerance and pulmonary function. There is only 1 published report of transmission of SARS virus from a pediatric patient.

CONCLUSIONS

Children and adolescents are susceptible to SARS-associated coronavirus infection, although the clinical course and outcome are more favorable in children younger than 12 years of age compared with adolescents and adults. Transmission of SARS from pediatric patients appears to be uncommon but is possible.

Detection of the nucleocapsid protein of severe acute respiratory syndrome coronavirus in serum: comparison with results of other viral markers

A capture enzyme-enhanced chemiluminescence immunoassay (ECLIA) based on three specific monoclonal antibodies to detect the nucleocapsid (N) protein of severe acute respiratory syndrome (SARS) associated coronavirus (SARS-CoV) in the serial serum samples from SARS patients was developed. The anti-SARS-CoV IgG and the viral RNA were also detected in the sera by ELISA and RT-PCR, respectively. During the first 10 days after onset, anti-SARS-CoV IgG, SARS-CoV RNA and the N protein were detected in 21.4, 42.9, and 90% of the patients’ sera, respectively. The detection rate of the N protein during days 11–15 of the disease was still significantly higher than those of anti-SARS-CoV IgG and SARS-CoV RNA. The data demonstrated that detection of the N protein with the capture ECLIA appears to be more useful than detection of other viral makers for rapid diagnosis of SARS in patients.