Effect of an enhanced public health contact tracing intervention on the secondary transmission of SARS-CoV-2 in educational settings : The four-way decomposition analysis
© 2024, Djuric et al..
Background: The aim of our study was to test the hypothesis that the community contact tracing strategy of testing contacts in households immediately instead of at the end of quarantine had an impact on the transmission of SARS-CoV-2 in schools in Reggio Emilia Province.
Methods: We analysed surveillance data on notification of COVID-19 cases in schools between 1 September 2020 and 4 April 2021. We have applied a mediation analysis that allows for interaction between the intervention (before/after period) and the mediator.
Results: Median tracing delay decreased from 7 to 3.1 days and the percentage of the known infection source increased from 34-54.8% (incident rate ratio-IRR 1.61 1.40-1.86). Implementation of prompt contact tracing was associated with a 10% decrease in the number of secondary cases (excess relative risk -0.1 95% CI -0.35-0.15). Knowing the source of infection of the index case led to a decrease in secondary transmission (IRR 0.75 95% CI 0.63-0.91) while the decrease in tracing delay was associated with decreased risk of secondary cases (1/IRR 0.97 95% CI 0.94-1.01 per one day of delay). The direct effect of the intervention accounted for the 29% decrease in the number of secondary cases (excess relative risk -0.29 95%-0.61 to 0.03).
Conclusions: Prompt contact testing in the community reduces the time of contact tracing and increases the ability to identify the source of infection in school outbreaks. Although there are strong reasons for thinking it is a causal link, observed differences can be also due to differences in the force of infection and to other control measures put in place.
Funding: This project was carried out with the technical and financial support of the Italian Ministry of Health - CCM 2020 and Ricerca Corrente Annual Program 2023.
| Medienart: |
E-Artikel |
|---|
| Erscheinungsjahr: |
2024 |
|---|---|
| Erschienen: |
2024 |
| Enthalten in: |
Zur Gesamtaufnahme - volume:13 |
|---|---|
| Enthalten in: |
eLife - 13(2024) vom: 28. Feb. |
| Sprache: |
Englisch |
|---|
| Beteiligte Personen: |
Djuric, Olivera [VerfasserIn] |
|---|
| Links: |
|---|
| Themen: |
Attack rate |
|---|
| Anmerkungen: |
Date Completed 29.02.2024 Date Revised 01.03.2024 published: Electronic Citation Status MEDLINE |
|---|
| doi: |
10.7554/eLife.85802 |
|---|
| funding: |
|
|---|---|
| Förderinstitution / Projekttitel: |
|
| PPN (Katalog-ID): |
NLM369060504 |
|---|
| LEADER | 01000caa a22002652 4500 | ||
|---|---|---|---|
| 001 | NLM369060504 | ||
| 003 | DE-627 | ||
| 005 | 20240301232744.0 | ||
| 007 | cr uuu---uuuuu | ||
| 008 | 240229s2024 xx |||||o 00| ||eng c | ||
| 024 | 7 | |a 10.7554/eLife.85802 |2 doi | |
| 028 | 5 | 2 | |a pubmed24n1313.xml |
| 035 | |a (DE-627)NLM369060504 | ||
| 035 | |a (NLM)38416129 | ||
| 035 | |a (PII)e85802 | ||
| 040 | |a DE-627 |b ger |c DE-627 |e rakwb | ||
| 041 | |a eng | ||
| 100 | 1 | |a Djuric, Olivera |e verfasserin |4 aut | |
| 245 | 1 | 0 | |a Effect of an enhanced public health contact tracing intervention on the secondary transmission of SARS-CoV-2 in educational settings |b The four-way decomposition analysis |
| 264 | 1 | |c 2024 | |
| 336 | |a Text |b txt |2 rdacontent | ||
| 337 | |a ƒaComputermedien |b c |2 rdamedia | ||
| 338 | |a ƒa Online-Ressource |b cr |2 rdacarrier | ||
| 500 | |a Date Completed 29.02.2024 | ||
| 500 | |a Date Revised 01.03.2024 | ||
| 500 | |a published: Electronic | ||
| 500 | |a Citation Status MEDLINE | ||
| 520 | |a © 2024, Djuric et al. | ||
| 520 | |a Background: The aim of our study was to test the hypothesis that the community contact tracing strategy of testing contacts in households immediately instead of at the end of quarantine had an impact on the transmission of SARS-CoV-2 in schools in Reggio Emilia Province | ||
| 520 | |a Methods: We analysed surveillance data on notification of COVID-19 cases in schools between 1 September 2020 and 4 April 2021. We have applied a mediation analysis that allows for interaction between the intervention (before/after period) and the mediator | ||
| 520 | |a Results: Median tracing delay decreased from 7 to 3.1 days and the percentage of the known infection source increased from 34-54.8% (incident rate ratio-IRR 1.61 1.40-1.86). Implementation of prompt contact tracing was associated with a 10% decrease in the number of secondary cases (excess relative risk -0.1 95% CI -0.35-0.15). Knowing the source of infection of the index case led to a decrease in secondary transmission (IRR 0.75 95% CI 0.63-0.91) while the decrease in tracing delay was associated with decreased risk of secondary cases (1/IRR 0.97 95% CI 0.94-1.01 per one day of delay). The direct effect of the intervention accounted for the 29% decrease in the number of secondary cases (excess relative risk -0.29 95%-0.61 to 0.03) | ||
| 520 | |a Conclusions: Prompt contact testing in the community reduces the time of contact tracing and increases the ability to identify the source of infection in school outbreaks. Although there are strong reasons for thinking it is a causal link, observed differences can be also due to differences in the force of infection and to other control measures put in place | ||
| 520 | |a Funding: This project was carried out with the technical and financial support of the Italian Ministry of Health - CCM 2020 and Ricerca Corrente Annual Program 2023 | ||
| 650 | 4 | |a Journal Article | |
| 650 | 4 | |a COVID-19 | |
| 650 | 4 | |a attack rate | |
| 650 | 4 | |a contact tracing | |
| 650 | 4 | |a epidemiology | |
| 650 | 4 | |a global health | |
| 650 | 4 | |a mediation analysis | |
| 650 | 4 | |a schools | |
| 650 | 4 | |a viruses | |
| 700 | 1 | |a Larosa, Elisabetta |e verfasserin |4 aut | |
| 700 | 1 | |a Cassinadri, Mariateresa |e verfasserin |4 aut | |
| 700 | 1 | |a Cilloni, Silvia |e verfasserin |4 aut | |
| 700 | 1 | |a Bisaccia, Eufemia |e verfasserin |4 aut | |
| 700 | 1 | |a Pepe, Davide |e verfasserin |4 aut | |
| 700 | 1 | |a Bonvicini, Laura |e verfasserin |4 aut | |
| 700 | 1 | |a Vicentini, Massimo |e verfasserin |4 aut | |
| 700 | 1 | |a Venturelli, Francesco |e verfasserin |4 aut | |
| 700 | 1 | |a Giorgi Rossi, Paolo |e verfasserin |4 aut | |
| 700 | 1 | |a Pezzotti, Patrizio |e verfasserin |4 aut | |
| 700 | 1 | |a Mateo Urdiales, Alberto |e verfasserin |4 aut | |
| 700 | 1 | |a Bedeschi, Emanuela |e verfasserin |4 aut | |
| 700 | 0 | |a Reggio Emilia Covid-19 Working Group |e verfasserin |4 aut | |
| 773 | 0 | 8 | |i Enthalten in |t eLife |d 2012 |g 13(2024) vom: 28. Feb. |w (DE-627)NLM221831460 |x 2050-084X |7 nnns |
| 773 | 1 | 8 | |g volume:13 |g year:2024 |g day:28 |g month:02 |
| 856 | 4 | 0 | |u http://dx.doi.org/10.7554/eLife.85802 |3 Volltext |
| 912 | |a GBV_USEFLAG_A | ||
| 912 | |a GBV_NLM | ||
| 951 | |a AR | ||
| 952 | |d 13 |j 2024 |b 28 |c 02 | ||