ABSTRACT
BACKGROUND: The performance characteristics of the Panbio™ COVID-19 Ag test was evaluated at an emergency room setting against RT-PCR, considered the gold-standard for the detection of SARS-CoV-2, in São Paulo, Brazil. The study aimed to determine the sensitivity, specificity, Positive Percent Agreement (PPA), and Negative Percent Agreement (NPA) as compared to RT-PCR. METHODS: Specimens from 127 suspected patients were tested by both the Panbio™ COVID-19 Ag test and by RT-PCR. RESULTS: In relation to RT-PCR using Ct values ≤ 40 as the upper limit for positivity, the Panbio™ COVID-19 Ag test showed an overall sensitivity of 84.3% (95% CI 75â93.8%) and 98.2% (95% CI 96â98.8%) overall specificity. For Ct values ≤ 25 (n = 37), the Panbio™ COVID-19 Ag test showed 97% sensitivity. DISCUSSION: The concordance between the Panbio™ COVID-19 Ag test and RT-PCR was 97% at Ct values below 25 but decreased at higher Ct values. For disease control, it is very important to identify infected individuals who present COVID-19 symptoms and also those who are suspected of infection due to contact with infected individuals. CONCLUSION: The Panbio™ COVID-19 Ag test is suitable for use as a diagnostic test for rapid screening of patients presenting COVID-19 symptoms, or those suspected of being infected, prior to being admitted to hospital.
Subject(s)
COVID-19 , Antigens, Viral , Brazil/epidemiology , COVID-19/diagnosis , Emergency Service, Hospital , Hospitals , Humans , SARS-CoV-2/genetics , Sensitivity and SpecificityABSTRACT
The first SARS-CoV-2 intrafamilial transmission was investigated in China. We evaluated the dynamics of SARS-CoV-2 transmission in 242 individuals from 60 family clusters, including 30 healthcare workers (HCW) and 30 patients, in São Paulo city. Sixty index cases with COVID-19 were selected, being 30 HCW index cases from Hospital São Paulo (HSP) and its 93 household contacts and 30 index case patients from Hospital Infantil Sabará (HIS) and its 89 household contacts. Asymptomatic and symptomatic individuals participating were tested for COVID-19. The secondary attack rates in the family clusters of HCW and HIS patients were 37.63% and 68.54%, respectively. Considering all households, the transmission from adults to children was 55.4%, while the transmission from children to children was 37.5%. Children were more infected if the index case was an adult, suggesting that children were less competent to transmit. The average time for a household to be COVID-19 positive was 4 and 3 days for HCW and HIS patients. Although HCW have a higher risk of infection and social vulnerability, the secondary attack rate was lower than that observed for HIS patients, possibly because HCW are more aware of transmission risks than the general community.
Subject(s)
COVID-19 , Adult , Brazil/epidemiology , COVID-19/epidemiology , Child , Health Personnel , Humans , Parents , SARS-CoV-2ABSTRACT
Background The performance characteristics of the Panbio™ COVID-19 Ag test was evaluated at an emergency room setting against RT-PCR, considered the gold-standard for the detection of SARS-CoV-2, in São Paulo, Brazil. The study aimed to determine the sensitivity, specificity, Positive Percent Agreement (PPA), and Negative Percent Agreement (NPA) as compared to RT-PCR. Methods Specimens from 127 suspected patients were tested by both the Panbio™ COVID-19 Ag test and by RT-PCR. Results In relation to RT-PCR using Ct values ≤ 40 as the upper limit for positivity, the Panbio™ COVID-19 Ag test showed an overall sensitivity of 84.3% (95% CI 75%‒93.8%) and 98.2% (95% CI 96%‒98.8%) overall specificity. For Ct values ≤ 25 (n = 37), the Panbio™ COVID-19 Ag test showed 97% sensitivity and a specificity of 73.3%. Discussion The concordance between the Panbio™ COVID-19 Ag test and RT-PCR was 97% at Ct values below 25 but decreased at higher Ct values. For disease control, it is very important to identify infected individuals who present COVID-19 symptoms and also those who are suspected of infection due to contact with infected individuals. Conclusion The Panbio™ COVID-19 Ag test is suitable for use as a diagnostic test for rapid screening of patients presenting COVID-19 symptoms, or those suspected of being infected, prior to being admitted to hospital.
ABSTRACT
In a single day, six of 150 (4%) asymptomatic visitors were diagnosed with COVID-19 at a hospital with a universal masking policy. Two inpatients (contacts) subsequently developed symptoms. More rigorous protective measures during visitation periods may need to be included in infection control practices to reduce nosocomial transmissions.