ABSTRACT
BACKGROUND: Understanding the immune response to the SARS-CoV-2 virus is critical for efficient monitoring and control strategies. The ProHEpic-19 cohort provides a fine-grained description of the kinetics of antibodies after SARS-CoV-2 infection with an exceptional resolution over 17 months. METHODS: We established a cohort of 769 healthcare workers including healthy and infected with SARS-CoV-2 in northern Barcelona to determine the kinetics of the IgM against the nucleocapsid (N) and the IgG against the N and spike (S) of SARS-CoV-2 in infected healthcare workers. The study period was from 5 May 2020 to 11 November 2021.We used non-linear mixed models to investigate the kinetics of IgG and IgM measured at nine time points over 17 months from the date of diagnosis. The model included factors of time, gender, and disease severity (asymptomatic, mild-moderate, severe-critical) to assess their effects and their interactions. FINDINGS: 474 of the 769 participants (61.6%) became infected with SARS-CoV-2. Significant effects of gender and disease severity were found for the levels of all three antibodies. Median IgM(N) levels were already below the positivity threshold in patients with asymptomatic and mild-moderate disease at day 270 after the diagnosis, while IgG(N and S) levels remained positive at least until days 450 and 270, respectively. Kinetic modelling showed a general rise in both IgM(N) and IgG(N) levels up to day 30, followed by a decay with a rate depending on disease severity. IgG(S) levels remained relatively constant from day 15 over time. INTERPRETATION: IgM(N) and IgG(N, S) SARS-CoV-2 antibodies showed a heterogeneous kinetics over the 17 months. Only the IgG(S) showed a stable increase, and the levels and the kinetics of antibodies varied according to disease severity. The kinetics of IgM and IgG observed over a year also varied by clinical spectrum can be very useful for public health policies around vaccination criteria in adult population. FUNDING: Regional Ministry of Health of the Generalitat de Catalunya (Call COVID19-PoC SLT16_04; NCT04885478).
Subject(s)
COVID-19 , Adult , Antibodies, Viral , COVID-19/epidemiology , Health Personnel , Humans , Immunity, Humoral , Immunoglobulin G , Immunoglobulin M , Pandemics , SARS-CoV-2 , Spain/epidemiologyABSTRACT
BACKGROUND: The epidemiological situation generated by COVID-19 has highlighted the importance of applying non-pharmacological measures in the management of the epidemic. Mass screening of the asymptomatic general population has been established as a priority strategy by carrying out diagnostic tests to detect possible cases, isolate contacts, cut transmission chains and thus limit the spread of the virus. OBJECTIVE: To evaluate the economic impact of mass COVID-19 screenings of an asymptomatic population during the first and second wave of the epidemic in Catalonia, Spain. METHODOLOGY: Cost-Benefit Analysis based on the estimated total costs of mass screening versus health gains and associated health costs avoided. RESULTS: Excluding the value of monetized health, the Benefit-Cost ratio was estimated at 0.45, a low value that would seem to advise against mass screening policies. However, if monetized health is included, the ratio is close to 1.20, reversing the interpretation. In other words, the monetization of health is the critical element that tips the scales in favour of the desirability of screening. Results show that the interventions with the highest return are those that maximize the percentage of positives detected. CONCLUSION: Efficient management of resources for the policy of mass screening in asymptomatic populations can generate high social returns. The positivity rate critically determines its desirability. Likewise, precocity in the detection of cases will cut more transmissions in the chain of contagion and increase the economic return of these interventions. Maximizing the value of resources depends on screening strategies being accompanied by contact-tracing and specific in their focus, targeting, for example, high-risk subpopulations with the highest rate of expected positives.
Subject(s)
COVID-19 , Contact Tracing , Cost-Benefit Analysis , Humans , SARS-CoV-2 , Spain/epidemiologyABSTRACT
Vaccine development is one of the fastest growing sectors in medicine now and in the future, as we are living with the emergency health care for the SARS-CoV-2 coronavirus. The semFYC PAPPS program biannually publishes the recommendations of the group and, in this edition, special emphasis is placed on the common vaccination proposed by the Ministry of Health, where, at last, it no longer discriminates between paediatrics and adults, and proposes a calendar throughout life. The main novelties in the field of vaccinology today are focused on the consolidation of the nonavalent vaccine against the human papilloma virus and in the change of the dose of monovalent meningitis vaccine C for the tetravalent one, ACWY, at age 12. The pandemic we are experiencing has led to the postponement of most preventive activities. On the return to «normality¼, the vaccination calendar must be examined, and completed if necessary.