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1.
Future Microbiol ; 17: 803-812, 2022 07.
Article in English | MEDLINE | ID: covidwho-1879383

ABSTRACT

Many underlying medical conditions have been linked to worse COVID-19 prognosis. Based on reports on SARS-CoV-1 and Middle East respiratory syndrome infections, pregnancy has been considered a predisposing factor to severe COVID-19, with pregnant women being a high-risk group for several physiological reasons. Specifically, pregnant women undergo physiological adaptations that predispose them to severe respiratory viral diseases, including SARS-CoV-2. However, a significant amount of evidence suggests that the clinical outcome of COVID-19 among pregnant women is not different from the general population. In view of this, this report discusses the physiological conditions in pregnant women that adversely affect their immunity, cardiovascular homeostasis, and their endothelial and coagulopathic functions, thereby making them more prone to severe viral infections. We also discuss how these physiological adaptations appear to paradoxically offer protection against severe COVID-19 among pregnant women.


Subject(s)
COVID-19 , Pregnancy Complications, Infectious , Female , Humans , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Pregnant Women , Prognosis , SARS-CoV-2
2.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-319535

ABSTRACT

Background: We set out to estimate the community-level exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Ghana. Methods: Phased seroprevalence studies of 2729 participants at selected locations across Ghana were conducted. Phase I (August 2020) sampled 1305 individuals at major markets/lorry stations, shopping malls, hospitals and research institutions involved in coronavirus disease 2019 (COVID-19) work. The study utilized a lateral flow rapid diagnostic test (RDT) which detected IgM and IgG antibodies against SARS-CoV-2 nucleocapsid protein. Results: : During Phase I, 252/1305 (19%) tested positive for IgM or IgG or both. Exposure was significantly higher at markets/lorry stations (26.9%) compared to malls (9.4%), with 41–60-year group demonstrating highest seropositivity (27.2%). Exposure was higher in participants with no formal education (26.2%) than those with tertiary education (13.1%);and higher in informally employed workers (24.0%) than those in the formal sector (15.0%). Results from phases II and III, in October and December 2020 respectively, implied either reduced transmissions or loss of antibody expression in some participants. The Upper East region showed the lowest seropositivity (2%). Phase IV, in February 2021, showed doubled seropositivity in the upper income bracket (26.2%) since August 2020, reflective of Ghana’s second wave of symptomatic COVID-19 cases. This suggested that high transmission rates had overcome the initial socioeconomic stratification of exposure risk. Reflective of second wave hospitalisation trends, the 21-40 age group demonstrated modal seropositivity (24.9) in Phase IV whilst 40-60 years and 60+ previously demonstrated highest prevalence. Conclusions: : Overall, the data indicates higher COVID-19 seroprevalence than officially acknowledged, likely implying a considerably lower-case fatality rate than the current national figure of 0.84%. The data also suggests that COVID-19 is predominantly asymptomatic COVID-19 in Ghana. The observed trends mimic clinical trends of infection and imply that the methodology used was appropriate.

3.
Biomark Med ; 16(1): 41-50, 2022 01.
Article in English | MEDLINE | ID: covidwho-1523645

ABSTRACT

Viral diseases remain a significant global health threat, and therefore prioritization of limited healthcare resources is required to effectively manage dangerous viral disease outbreaks. In a pandemic of a newly emerged virus that is yet to be well understood, a noninvasive host-derived prognostic biomarker is invaluable for risk prediction. Red blood cell distribution width (RDW), an index of red blood cell size disorder (anisocytosis), is a potential predictive biomarker for severity of many diseases. In view of the need to prioritize resources during response to outbreaks, this review highlights the prospects and challenges of RDW as a prognostic biomarker for viral infections, with a focus on hepatitis and COVID-19, and provides an outlook to improve the prognostic performance of RDW for risk prediction in viral diseases.


Subject(s)
Erythrocyte Indices , Virus Diseases/diagnosis , Animals , Biomarkers/analysis , Biomarkers/blood , COVID-19/blood , COVID-19/diagnosis , Erythrocytes/cytology , Hepatitis/blood , Hepatitis/diagnosis , Humans , Prognosis , Virus Diseases/blood
4.
J Infect ; 84(1): 48-55, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1446863

ABSTRACT

Background Controlling the spread of SARS-CoV-2 is problematic because of transmission driven by asymptomatic and pre-symptomatic individuals. Community screening can help identify these individuals but is often too expensive for countries with limited health care resources. Low-cost ELISA assays may address this problem, but their use has not yet been widely reported. Methods We developed a SARS-CoV-2 nucleocapsid ELISA and assessed its diagnostic performance on nose and throat swab samples from UK hospitalised patients and sputum samples from patients in Ghana. Results The ELISA had a limit of detection of 8.4 pg/ml antigen and 16 pfu/ml virus. When tested on UK samples (128 positive and 10 negative patients), sensitivity was 58.6% (49.6-67.2) rising to 78.3% (66.7-87.3) if real-time PCR Ct values > 30 were excluded, while specificity was 100% (69.2-100). In a second trial using the Ghanaian samples (121 positive, 96 negative), sensitivity was 52% (42.8-61.2) rising to 72.6% (61.8-81.2) when a > 30 Ct cut-off was applied, while specificity was 100% (96.2-100). Conclusions: Our data show that nucleocapsid ELISAs can test a variety of patient sample types while achieving levels of sensitivity and specificity required for effective community screening. Further investigations into the opportunities that this provides are warranted.


Subject(s)
COVID-19 , SARS-CoV-2 , Enzyme-Linked Immunosorbent Assay , Ghana , Humans , Nucleocapsid , Sensitivity and Specificity
7.
Nature ; 590(7845): 320-325, 2021 02.
Article in English | MEDLINE | ID: covidwho-953381

ABSTRACT

The expanding pandemic of coronavirus disease 2019 (COVID-19) requires the development of safe, efficacious and fast-acting vaccines. Several vaccine platforms are being leveraged for a rapid emergency response1. Here we describe the development of a candidate vaccine (YF-S0) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that uses live-attenuated yellow fever 17D (YF17D) vaccine as a vector to express a noncleavable prefusion form of the SARS-CoV-2 spike antigen. We assess vaccine safety, immunogenicity and efficacy in several animal models. YF-S0 has an excellent safety profile and induces high levels of SARS-CoV-2 neutralizing antibodies in hamsters (Mesocricetus auratus), mice (Mus musculus) and cynomolgus macaques (Macaca fascicularis), and-concomitantly-protective immunity against yellow fever virus. Humoral immunity is complemented by a cellular immune response with favourable T helper 1 polarization, as profiled in mice. In a hamster model2 and in macaques, YF-S0 prevents infection with SARS-CoV-2. Moreover, a single dose conferred protection from lung disease in most of the vaccinated hamsters within as little as 10 days. Taken together, the quality of the immune responses triggered and the rapid kinetics by which protective immunity can be attained after a single dose warrant further development of this potent SARS-CoV-2 vaccine candidate.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Genetic Vectors/genetics , SARS-CoV-2/immunology , Vaccines, Attenuated/immunology , Yellow Fever Vaccine/genetics , Animals , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/genetics , Cricetinae , Disease Models, Animal , Female , Glycosylation , Macaca fascicularis/genetics , Macaca fascicularis/immunology , Macaca fascicularis/virology , Male , Mesocricetus/genetics , Mesocricetus/immunology , Mesocricetus/virology , Mice , Safety , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/genetics
8.
Microb Biotechnol ; 14(1): 126-135, 2021 01.
Article in English | MEDLINE | ID: covidwho-947730

ABSTRACT

Viruses remain a significant public health concern worldwide. Recently, humanity has faced deadly viral infections, including Zika, Ebola and the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The threat is associated with the ability of the viruses to mutate frequently and adapt to different hosts. Thus, there is the need for robust detection and classification of emerging virus strains to ensure that humanity is prepared in terms of vaccine and drug developments. A point or stand-off biosensor that can detect and classify viruses from indoor and outdoor environments would be suited for viral surveillance. Light detection and ranging (LiDAR) is a facile and versatile tool that has been explored for stand-off detection in different environments including atmospheric, oceans and forest sensing. Notably, laser-induced fluorescence-light detection and ranging (LIF-LiDAR) has been used to identify MS2 bacteriophage on artificially contaminated surgical equipment or released amidst other primary biological aerosol particles in laboratory-like close chamber. It has also been shown to distinguish between different picornaviruses. Currently, the potentials of the LIF-LiDAR technology for real-time stand-off surveillance of pathogenic viruses in indoor and outdoor environments have not been assessed. Considering the increasing applications of LIF-LiDAR for potential microbial pathogens detection and classification, and the need for more robust tools for viral surveillance at safe distance, we critically evaluate the prospects and challenges of LIF-LiDAR technology for real-time stand-off detection and classification of potentially pathogenic viruses in various environments.


Subject(s)
Environmental Monitoring/methods , Viruses/isolation & purification , Algorithms , Containment of Biohazards , Fluorescence , Lasers , Machine Learning , Virion/isolation & purification , Viruses/classification
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