RESUMO
Background: The Omicron variant of SARS-CoV-2 is now overtaking the Delta variant in many countries. Results showing that sera from double vaccinated individuals have minimal neutralizing activity against Omicron may indicate that the higher rate of transmission is due to evasion from vaccine-induced immunity. However, there is little information about activation of recall responses to Omicron in vaccinated individuals. Methods: We measured inflammatory mediators, antibodies to the SARS-CoV-2 spike and nucleocapsid proteins, and spike peptide-induced release of interferon gamma in whole blood in 51 vaccinated individuals infected with Omicron, in 14 infected with Delta, and in 18 healthy controls. The median time points for the first and second samples were 7 and 14 days after symptom onset, respectively. Findings: Infection with Omicron or Delta led to a rapid and similar increase in antibodies to the SARS-CoV-2 spike and nucleocapsid proteins and spike peptide-induced interferon gamma in whole blood. Both the Omicron and the Delta infected patients had a mild and transient increase in inflammatory parameters. Interpretation: The results suggest that vaccine-induced immunological memory yields similar coverage for the Omicron and Delta variants.
Assuntos
Hepatite D , Doenças do Sistema ImunitárioRESUMO
Background: For many people public transport is the only mode of travel, and it can be challenging to keep the necessary distances in such a restricted space. The exact role of public transportation and risk of SARS-CoV-2 transmission is not known. Methods: : Participants (n=121 374) were untested adult Norwegian residents recruited through social media who in the spring of 2020 completed a baseline questionnaire on demographics and use of public transport. Incident cases (n=1069) had a positive SARS-CoV-2 polymerase chain reaction test registered at the Norwegian Messaging System for Infectious Diseases by January 27, 2021. We investigated the association between use of public transport and SARS-CoV-2 using logistic regression. Odds ratios (ORs) with 95% confidence intervals (CIs) adjusted for age, calendar time, gender, municipality, smoking, income level, fitness and underlying medical conditions were estimated. Frequency of use of public transport was reported for 2 week-periods. Results: : Before lockdown, those who tested positive on SARS-CoV-2 were more likely to have used public transport 1-3 times (OR =1.28, CI 1.09-1.51), 4-10 times (OR=1.49, CI 1.26-1.77) and ≥11 times (OR=1.50, CI 1.27-1.78, p for trend<0.0001) than those who had not tested positive. Conclusion: Use of public transport was positively associated with contracting SARS-CoV-2 both before and after lockdown.
Assuntos
Doenças TransmissíveisRESUMO
Background The risk factors for SARS-CoV-2 transmission are not well characterised. We sought to identify potential risk factors for transmission and actionable information that can be used to prevent SARS-CoV-2. Methods Individuals tested for SARS-CoV-2 at four accredited laboratories were invited. In addition, participants were recruited through a media campaign. Self-reported SARS-CoV-2 test results were compared with laboratory results, demographic data and behavioural facts were collected using a digital platform. In a cross-sectional design positive cases were compared with negative and untested control groups. Findings Approximately 14 days after a countrywide lockdown in Norway, 116,678 participants were included. Median age was 46 years, 44% had children in preschool or in school; 18% were practicing health professionals. International flights, contact with infected individuals, and gatherings of more than 50 people, were associated with increased risk of testing positive. Health professionals who treated COVID-19 patients were at higher risk of testing positive than those who did not. Having undergone light infections, the last six months was strongly associated with lower odds ratio of SARS-CoV-2 positivity. Contact with children, use of hand sanitiser and use of protective gloves in private were also associated with lower odds ratio of testing positive for SARS-CoV-2. Interpretation Further research is needed to explore if being a parent or looking after children is associated with lower risk of SARS-CoV-2 positivity in the next phases of the pandemic. Immunological research should be done to determine the effects of prior trivial infections on SARS-CoV-2 infection. We confirm that large gatherings during the pandemic should be avoided and those who are infected, or under suspicion thereof, posed very high risks to others in this population. Registration: Trial registration: ClinicalTrials.gov: NTC 04320732, March 25, 2020.
Assuntos
COVID-19RESUMO
Background The risk factors for SARS-CoV-2 transmission are not well characterised in Western populations. We sought to identify potential risk factors for transmission and actionable information to prevent for SARS-CoV-2. Methods Individuals tested for SARS-CoV-2 at three major laboratories were invited. In addition, participants were sampled by convenience after a media campaign. Self-reported test results were compared with laboratory results, demographic data and behavioural facts were collected using a digital platform. In a cross-sectional design positive cases were compared with negative and untested control groups. Findings Approximately than 14 days after lockdown, 116,678 participants were included. Median age was 46 years, 44% had children in preschool or in school; 18% were practicing health professionals. International flights, contact with infected, and gatherings of more than 50 people, were associated with high risk. Health professionals who used public transport were at higher risk of testing positive than those who did not. Having undergone light infections, the last six months was strongly associated with lower odds ratio of SARS-CoV-2 positivity. Contact with children, use of hand sanitiser and use of protective gloves in private were also associated with lower odds ratio of testing positive for SARS-CoV-2. Interpretation Further research is needed to explore if being a parent or looking after children is associated with lower risk of SARS-CoV-2 positivity in the next phases of the pandemic. Immunological research should be done to determine the effects of prior trivial infections on SARS-CoV-2 infection. We confirm that large gatherings during the pandemic should be avoided and those who are infected, or under suspicion thereof, posed very high risks to others this population.