Colonization of severe acute respiratory syndrome-associated coronavirus among health-care workers screened by nasopharyngeal swab

Seasonal variation of asymptomatic viral and bacterial nasopharyngeal carriage in rural Senegal

BACKGROUND

The surveillance of respiratory pathogens in rural areas of West Africa has, to date, largely been focussed on symptoms. In this prospective study conducted prior to the COVID-19 pandemic, we aimed to assess the asymptomatic prevalence of respiratory pathogen carriage in a group of individuals living in a rural area of Senegalese.

METHODS

Longitudinal follow up was performed through monthly nasopharyngeal swabbing during the dry season and weekly swabbing during the rainy season. We enrolled 15 individuals from the village of Ndiop. A total of 368 nasopharyngeal swabs were collected over a one-year period. We investigated the prevalence of 18 respiratory viruses and eight respiratory bacteria in different age groups using singleplex and multiplex PCR.

RESULTS

In total, 19.56% of the samples (72/368) were positive for respiratory viruses and 13.60% of the samples (50/368) were positive for respiratory bacteria. Coronaviruses (19/72, 26.39%), adenoviruses (17/72, 23.61%), rhinoviruses (14/72, 19.44%), Streptococcus pneumoniae (17/50, 34%), and Moraxella catarrhalis (15/50, 30%) were the most frequently detected viruses. Interestingly, the carriage of respiratory pathogens was shown to be more frequent during the rainy season, as pluviometry was shown to be positively associated with the occurrence of respiratory viruses such as influenza (P = .0078, r2 =.523) and RSV (P = .0055, r2 =.554).

CONCLUSIONS

Our results show a non-negligible circulation of respiratory pathogens in a rural area in Senegal (West Africa) with an underestimated proportion of asymptomatic individuals. This study highlights the fact that the circulation of viruses and bacteria in the community has been overlooked.

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-1) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infections in pregnancy - An overview

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-1) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infections, like most other viruses that affect the respiratory tract can cause severe maternal illness and adverse pregnancy outcomes. They are not only highly transmissible (acquired through droplets), but Host reservoirs such as dromedary camels for MERS-CoV and masked palm civet for SARS-CoV-1 are critical links in the onset of outbreaks. Clinically they present with flu-like symptoms and therefore a high index of suspicion is required to ensure timely diagnosis and tailored management. Although there are not many reported series on these infections in pregnancy they seem to be associated with an increased risk of preterm delivery and maternal mortality. Diagnosis is made by PCR from nasopharyngeal swabs. There are currently no effective anti-viral agents for these viruses but following infections various agents have been administered to patients. The most important aspect of management should be early identification of deterioration and intensive support and prevention of transmission. Our understanding of the evidence of the impact of both infections on pregnancies suggests the potential for future repeat outbreaks, hence the importance of maintaining vigilance across healthcare systems.

Managing a Department of Obstetrics and Gynecology in Times of COVID-19 Outbreak: The Foch Hospital Experience

Departments of Gynecology and Obstetrics, as other departments, were faced with a major challenge at the outbreak of the COVID-19 pandemic. Fast restructuring was necessary in order to provide the means for COVID-related care. In this article we share our 1-year experience in reshaping our activities, managing healthcare workers and securing a pathway for pregnant patients, including potential, and confirmed COVID-19 cases. Priorities were set on ensuring patients' and healthcare workers' safety. Key containment measures included facemasks, systematic screening, dedicated spaces for COVID-19 cases with reinforced measures and vaccination campaign.

Clinical outcomes of patients hospitalized for COVID-19 versus SARS: a meta-analysis

Estimating the case-fatality rate and clinical outcomes for patients with coronavirus disease 2019 (COVID-19) is crucial because health care systems must adequately prepare for outbreaks and design appropriate policies. A systematic search of PubMed, Embase, and Medline+Journal (via OVID) were conducted for relevant journal publications from database inception to May 4, 2020. Articles that reported the fatality rates and clinical outcomes of patients hospitalized for COVID-19 or severe acute respiratory syndrome (SARS) infection were included. Nine clinical reports (four SARS reports and five COVID-19 reports) with a total of 851 patients (367 and 484 patients with SARS and COVID-19, respectively) were analyzed. A greater proportion of hospitalized patients with COVID-19 had bilateral pneumonia (90.0% [76.3%-96.2%] vs. 35.9% [21.4%-53.6%], p < 0.001) and required ventilators (23.8% [18.8%-29.6%] vs. 15.3% [11.9%-19.4%], p = 0.010) compared with hospitalized patients with SARS. The case-fatality rate was 9.5% (6.5%-13.7%) and 6.1% (3.5%-10.3%) among patients with COVID-19 and SARS, respectively (p = 0.186). The case-fatality rate among hospitalized patients with COVID-19 was comparable to that during the 2003 SARS outbreak. A higher incidence of bilateral pneumonia and increased ventilator usage were noted among patients with COVID-19 compared with patients with SARS.

Cytologic and molecular correlates of SARS-CoV-2 infection of the nasopharynx

Infection by SARS-CoV-2 commonly begins in the nasopharynx, and the cytologic and molecular correlates are not characterized. Fifty-eight cytologic preps (20 oral and 38 from the nasopharynx) were obtained from ten patients and analyzed in a blinded fashion for SARS-CoV-2 spike and envelope protein by immunohistochemistry and viral RNA by in situ hybridization. qRTPCR identified three positive cases and seven controls; the three cases reported mild symptoms that resolved in 2-3 days. Blinded analyses confirmed the presence of the SARS-CoV-2 spike and envelope proteins and viral RNA in the three cases and viral absence in the seven controls. A signal for the positive cases was evident in each nasopharyngeal and none of the oral samples. Viral RNA/proteins localized exclusively to glandular cells and was present in high copy number. Blinded analysis of the cytology documented that the glandular cells infected by SARS-CoV-2 showed marked degeneration with ciliocytophthoria; viral inclusions were not evident. Co-expression analysis showed viral infected cells had increased apoptosis, marked by strong expression of activated caspase 3. Weekly serial testing of two of the cases showed persistence of productive viral infection for up to 2 weeks after symptom onset. It is concluded that the target cell of SARS-CoV-2 in the head and neck region is the glandular cell of the nasal passages, that viral infection is lytic and associated with high copy number that facilitates viral spread. The method outlines a simple, rapid test for productive SARS-CoV-2 based on immunohistochemistry or in situ hybridization of the glandular cells from the nasopharynx.

Seasonal variation of respiratory pathogen colonization in asymptomatic health care professionals: A single-center, cross-sectional, 2-season observational study

BACKGROUND

The purpose of this study was to determine the seasonal variance of potentially pathogenic bacterial and viral organisms in nasopharyngeal specimens obtained from asymptomatic health care professionals (HCPs) during the 2014 winter and summer months.

METHODS

Nasopharyngeal specimens from 100 HCPs were collected from Huntsville Hospital (Huntsville, AL) during the winter and from 100 HCPs during the summer. All subjects were tested for 22 viruses and 19 bacteria using Target Enriched Multiplex Polymerase Chain Reaction. Both seasonal cohorts were composed of students, nurses, physicians, and residents.

RESULTS

Of the 100 HCPs tested during the winter, 34 subjects were colonized with at least 1 bacterium, and 11 tested positive for at least 1 virus. Methicillin-resistant Staphylococcus aureus (MRSA), Moraxella catarrhalis, and coronavirus were the most frequently detected potentially infectious agents. Of the 100 HCPs tested during the summer, 37 tested positive for at least 1 bacterium, and 4 tested positive for a viral agent. The most prevalent bacteria were MRSA and Klebsiella pneumonia.

CONCLUSION

Nasopharyngeal carriage among asymptomatic HCPs was common, but the frequency and presence of potential pathogens varied with each season. Understanding the colonization and infection potential of upper respiratory organisms is important, particularly for viruses. Although asymptomatic HCPs certainly harbor a number of different potentially infectious agents, future studies are needed to determine whether colonized pathogens are transmitted or initiate infection in at-risk patient populations.

An observational, laboratory-based study of outbreaks of middle East respiratory syndrome coronavirus in Jeddah and Riyadh, kingdom of Saudi Arabia, 2014

Background. In spring 2014, a sudden rise in the number of notified Middle East respiratory syndrome coronavirus (MERS-CoV) infections occurred across Saudi Arabia with a focus in Jeddah. Hypotheses to explain the outbreak pattern include increased surveillance, increased zoonotic transmission, nosocomial transmission, and changes in viral transmissibility, as well as diagnostic laboratory artifacts.

Methods. Diagnostic results from Jeddah Regional Laboratory were analyzed. Viruses from the Jeddah outbreak and viruses occurring during the same time in Riyadh, Al-Kharj, and Madinah were fully or partially sequenced. A set of 4 single-nucleotide polymorphisms distinctive to the Jeddah outbreak were determined from additional viruses. Viruses from Riyadh and Jeddah were isolated and studied in cell culture.

Results. Up to 481 samples were received per day for reverse transcription polymerase chain reaction (RT-PCR) testing. A laboratory proficiency assessment suggested positive and negative results to be reliable. Forty-nine percent of 168 positive-testing samples during the Jeddah outbreak stemmed from King Fahd Hospital. All viruses from Jeddah were monophyletic and similar, whereas viruses from Riyadh were paraphyletic and diverse. A hospital-associated transmission cluster, to which cases in Indiana (United States) and the Netherlands belonged, was discovered in Riyadh. One Jeddah-type virus was found in Riyadh, with matching travel history to Jeddah. Virus isolates representing outbreaks in Jeddah and Riyadh were not different from MERS-CoV EMC/2012 in replication, escape of interferon response, or serum neutralization.

Conclusions. Virus shedding and virus functions did not change significantly during the outbreak in Jeddah. These results suggest the outbreaks to have been caused by biologically unchanged viruses in connection with nosocomial transmission.

Transmission of MERS-coronavirus in household contacts

BACKGROUND

Strategies to contain the Middle East respiratory syndrome coronavirus (MERS-CoV) depend on knowledge of the rate of human-to-human transmission, including subclinical infections. A lack of serologic tools has hindered targeted studies of transmission.

METHODS

We studied 26 index patients with MERS-CoV infection and their 280 household contacts. The median time from the onset of symptoms in index patients to the latest blood sampling in contact patients was 17.5 days (range, 5 to 216; mean, 34.4). Probable cases of secondary transmission were identified on the basis of reactivity in two reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assays with independent RNA extraction from throat swabs or reactivity on enzyme-linked immunosorbent assay against MERS-CoV S1 antigen, supported by reactivity on recombinant S-protein immunofluorescence and demonstration of neutralization of more than 50% of the infectious virus seed dose on plaque-reduction neutralization testing.

RESULTS

Among the 280 household contacts of the 26 index patients, there were 12 probable cases of secondary transmission (4%; 95% confidence interval, 2 to 7). Of these cases, 7 were identified by means of RT-PCR, all in samples obtained within 14 days after the onset of symptoms in index patients, and 5 were identified by means of serologic analysis, all in samples obtained 13 days or more after symptom onset in index patients. Probable cases of secondary transmission occurred in 6 of 26 clusters (23%). Serologic results in contacts who were sampled 13 days or more after exposure were similar to overall study results for combined RT-PCR and serologic testing.

CONCLUSIONS

The rate of secondary transmission among household contacts of patients with MERS-CoV infection has been approximately 5%. Our data provide insight into the rate of subclinical transmission of MERS-CoV in the home.

Efficacy of cineole in patients suffering from acute bronchitis: a placebo-controlled double-blind trial

Objective

Cineole has mucolytic, bronchodilating and anti-inflammatory properties and reduces the exacerbation rate in patients suffering from COPD, as well as ameliorates symptoms in patients suffering from asthma and rhinosinusitis. Based on these effects, we therefore postulated the hypothesis that patients with acute bronchitis would also benefit from therapy with Cineole.

Methods

As part of a double-blind, placebo-controlled, multi-center-study, a total of 242 patients with confirmed acute bronchitis was randomly selected to participate. Over a period of 10 days, all patients were administered 3 x 200 mg of Cineole, or a respective placebo, per day. The primary outcome measure was a Bronchitis Sum Score, which summarises the relevant symptoms of acute bronchitis.

Results

After 4 days of treatment it was notable, that the patient group treated with Cineole, showed significantly more improvements of the bronchitis-sum-score than those of the placebo group (p = 0.0383). The statistical significant difference of the individual outcome measures was especially underlined by the frequency of cough fits by p = 0.0001 after 4 days.

Conclusions

The effects of Cineole in the treatment of acute bronchitis were clearly measurable and could be proven after a treatment period of merely 4 days. This study corroborates the fact that Cineole actively and significantly reduces cough frequency after four days. Therefore it has been shown to have a great socioeconomic impact.

Trial registration

ISRCTN: ISRCTN37784439

Severe acute respiratory syndrome (SARS)

This article reviews the virology, history, pathology, epidemiology, clinical presentations, complications, radiology, laboratory testing, diagnosis, treatment, and prevention of severe respiratory distress syndrome, with reference to documented outbreaks of the disease.

Pandemic planning in China: applying lessons from severe acute respiratory syndrome

There were three events of severe acute respiratory syndrome (SARS) in China from 2003 to 2004. Starting from 2002, we are also aware of the increasing alert of an avian flu pandemic. Epidemics of SARS and avian flu have posed huge threats to social stability, economic prosperity and human health in this country. What we have experienced during SARS outbreaks has great implications for the protection of people against a resurgence of SARS and potential attacks of high-pathogenic avian flu viruses. To that end, China has been preparing to contain future pandemics by applying lessons learnt from SARS.

Duration and distance of exposure are important predictors of transmission among community contacts of Ontario SARS cases

We report attack rates and contact-related predictors among community contacts of severe acute respiratory syndrome (SARS) cases from the 2003 Toronto-area outbreak. Community contact data was extracted from public health records for single, well-defined exposures to a SARS case. In total, 8662 community-acquired exposures resulted in 61 probable cases; a crude attack rate of 0.70% [95% confidence interval (CI) 0.54-0.90]. Persons aged 55-69 years were at higher risk of acquiring SARS (1.14%) than those either younger (0.60%) or older (0.70%). In multivariable analysis exposures for at least 30 min at a distance of <or=1 m increased the likelihood of becoming a SARS case 20.4-fold (95% CI 11.8-35.1). Risk related to duration of illness in the source case at time of exposure was greatest for illness duration of 7-10 days (rate ratio 3.4, 95% CI 1.9-6.1). Longer and closer proximity exposures incurred the highest rate of disease. Separate measures of time and distance from source cases should be added to minimum datasets for the assessment of interventions for SARS and other emerging diseases.