Dataset Information

Impact of tiered measures on social contact and mixing patterns of in Italy during the second wave of COVID-19.

ABSTRACT:

Background

Most countries around the world enforced non-pharmaceutical interventions against COVID-19. Italy was one of the first countries to be affected by the pandemic, imposing a hard lockdown, in the first epidemic wave. During the second wave, the country implemented progressively restrictive tiers at the regional level according to weekly epidemiological risk assessments. This paper quantifies the impact of these restrictions on contacts and on the reproduction number.

Methods

Representative (with respect to age, sex, and region of residence) longitudinal surveys of the Italian population were undertaken during the second epidemic wave. Epidemiologically relevant contact patterns were measured and compared with pre-pandemic levels and according to the level of interventions experienced by the participants. Contact matrices were used to quantify the reduction in the number of contacts by age group and contact setting. The reproduction number was estimated to evaluate the impact of restrictions on the spread of COVID-19.

Results

The comparison with the pre-pandemic baseline shows a significant decrease in the number of contacts, independently from the age group or contact settings. This decrease in the number of contacts significantly depends on the strictness of the non-pharmaceutical interventions. For all levels of strictness considered, the reduction in social mixing results in a reproduction number smaller than one. In particular, the impact of the restriction on the number of contacts decreases with the severity of the interventions.

Conclusions

The progressive restriction tiers implemented in Italy reduced the reproduction number, with stricter interventions associated with higher reductions. Readily collected contact data can inform the implementation of mitigation measures at the national level in epidemic emergencies to come.

SUBMITTER: Tizzani M

PROVIDER: S-EPMC10195658 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Publications

Impact of tiered measures on social contact and mixing patterns of in Italy during the second wave of COVID-19.

Tizzani Michele M De Gaetano Alessandro A Jarvis Christopher I CI Gimma Amy A Wong Kerry K Edmunds W John WJ Beutels Philippe P Hens Niel N Coletti Pietro P Paolotti Daniela D

BMC public health 20230519 1

<h4>Background</h4>Most countries around the world enforced non-pharmaceutical interventions against COVID-19. Italy was one of the first countries to be affected by the pandemic, imposing a hard lockdown, in the first epidemic wave. During the second wave, the country implemented progressively restrictive tiers at the regional level according to weekly epidemiological risk assessments. This paper quantifies the impact of these restrictions on contacts and on the reproduction number.<h4>Methods< ...[more]

PMID: 37202734

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Project description:BackgroundClose contact between an infectious and susceptible person is an important factor in respiratory disease transmission. Information on social contacts and mixing patterns in a population is crucial to understanding transmission patterns and informing transmission models of respiratory infections. Although West Africa has one of the highest burdens of respiratory infections, there is a lack of data on interpersonal contact and mixing patterns in this region.MethodsBetween January and November 2022, we conducted a cross-sectional, social contact survey within the population of the Central and Upper River Regions of The Gambia. Selected participants completed a questionnaire about their travel history and social contacts, detailing the number, intensity, location, frequency, duration, and age of contacts. We calculated age-standardized contact matrices to determine contact patterns in the population.ResultsOverall, individuals made an average of 12.7 (95% CI: 12.4-13.0) contacts per day. Contact patterns were mostly age-assortative and 84.5% of all contacts were physical. School-aged children (5-14 years) had the highest mean number of physical contacts (11.3, 95% CI: 10.9-11.8) while the < 1-year age group had the fewest contacts (9.4, 95% CI: 9.1-9.8). A large proportion of contacts (78%) occurred at home. Daily number of contacts increased with household size. While we did not observe any effect of gender on contact patterns, there were seasonal variations in contact type. Non-physical contacts were higher during the dry season compared to the rainy season. In contrast, there were more physical contacts in the rainy season compared to the dry season.ConclusionsIn rural Gambia, social contact patterns were primarily driven by household mixing. Most contacts were physical and mostly age-assortative, particularly among school-aged children. Our data can improve infectious disease transmission models of respiratory pathogens in high-transmission settings, which are valuable for optimizing the delivery of different interventions.

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Dataset Information

Impact of tiered measures on social contact and mixing patterns of in Italy during the second wave of COVID-19.

Background

Methods

Results

Conclusions

Publications

Impact of tiered measures on social contact and mixing patterns of in Italy during the second wave of COVID-19.

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