ABSTRACT
Testing is essential for detecting COVID-19 and differentiating it from other respiratory infections with similar symptoms. We investigated the sampling depth to optimize the COVID-19 diagnostics in a real world decentralized setting. Subjects: 160 randomly selected subjects were included, all visiting medical center either exposed to COVID-19 or as symptomatic. Mean age was 17 years (range 1-79), and 57 subjects were <= 6 years of age. Method(s): Nasopharyngeal (NP) and anterior nasal (NS) specimen were collected from all and a subgroup of PCRor mid-turbinate (>=18 years) samples were included. All COVID-19 positive findings (NP or NS) were assumed to be true positives based on the high specificity of the used automated mariPOC (ArcDia Ltd, Finland) SARS-CoV-2 antigen test (>99.8%). Symptoms, COVID-19 vaccinations and other background information were obtained. Result(s): Detection of 11 possible different respiratory pathogens resulted in 41 NP-positive (26%) and 33 NSpositive (21%) results, of which positive for COVID-19 were 26 NP and 21 NS samples, respectively The best detection rate for COVID-19 was among subjects <=6 years of age, 100% for NS compared with 88% for NP. The negative percent agreement was high among all subjects regardless of symptoms (91-99%), whereas detection rate diminished by the length of sick days of >= 4. Conclusion(s): Anterior nasal specimen from the nostrils shows high potential in detecting COVID-19 in small children with a rapid antigen test. Nasal sampling may decrease the need of COVID-19 testing resources compared to NP swab, thus enabling allocation of resources for more effective infection control.
ABSTRACT
Background: The COVID-19 pandemic caused by novel SARS-COV-2 has caused a sudden and substantial increase in hospitalisations. The incidence and severity are higher among elderly patients, and those with co-morbidities. Its severity has been linked with the viral load of infection. We aim to investigate the link of age and viral load with patients’ symptoms and their laboratory findings at the time of presentation to hospital. Methods: Cross-sectional, observational study of randomly selected COVID-19 RT PCR positive indoor patients. Results: Patients above 50 years of age were more in number than those less than 50 years of age. Shortness of breath, cough (dry/ sputum), body ache and fever were the main presenting complaints in both age groups. In patients below 50 years of age, those with a high viral load were reported to have a lower SpO2 (p = 0.07) than patients with a low viral load. In patients above 50 years, those with a high viral load were found to have a lower SpO2 (p = 0.009), higher HRCT scores (CT Severity Score) (p = 0.0002) and higher Neutrophil Lymphocyte Ratio (NLR) (p = 0.09), as compared to patients with a low viral load. In patients with a low viral load, the NLR was found to be higher (p = 0.007) in those above 50 years. Finally, in patients with a high viral load, higher HRCT scores (p = 0.08) were found in those above 50 years. Conclusion: Our results indicate that a higher age can adversely affect some biomarkers and disease outcome, irrespective of the viral load of the patients. At the same time, we found that a higher viral load can also adversely affect the severity of disease, irrespective of the age of patients.