Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis
Abstract Background The spatial spread of many mosquito-borne diseases occurs by focal spread at the scale of a few hundred meters and over longer distances due to human mobility. The relative contributions of different spatial scales for transmission of chikungunya virus require definition to impro...
| Main Authors: | , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2020-08-01
|
| Series: | BMC Medicine |
| Subjects: | |
| Online Access: | http://link.springer.com/article/10.1186/s12916-020-01674-y |
| _version_ | 1828489647042330624 |
|---|---|
| author | Giorgio Guzzetta Francesco Vairo Alessia Mammone Simone Lanini Piero Poletti Mattia Manica Roberto Rosa Beniamino Caputo Angelo Solimini Alessandra Della Torre Paola Scognamiglio Alimuddin Zumla Giuseppe Ippolito Stefano Merler |
| author_facet | Giorgio Guzzetta Francesco Vairo Alessia Mammone Simone Lanini Piero Poletti Mattia Manica Roberto Rosa Beniamino Caputo Angelo Solimini Alessandra Della Torre Paola Scognamiglio Alimuddin Zumla Giuseppe Ippolito Stefano Merler |
| author_sort | Giorgio Guzzetta |
| collection | DOAJ |
| description | Abstract Background The spatial spread of many mosquito-borne diseases occurs by focal spread at the scale of a few hundred meters and over longer distances due to human mobility. The relative contributions of different spatial scales for transmission of chikungunya virus require definition to improve outbreak vector control recommendations. Methods We analyzed data from a large chikungunya outbreak mediated by the mosquito Aedes albopictus in the Lazio region, Italy, consisting of 414 reported human cases between June and November 2017. Using dates of symptom onset, geographic coordinates of residence, and information from epidemiological questionnaires, we reconstructed transmission chains related to that outbreak. Results Focal spread (within 1 km) accounted for 54.9% of all cases, 15.8% were transmitted at a local scale (1–15 km) and the remaining 29.3% were exported from the main areas of chikungunya circulation in Lazio to longer distances such as Rome and other geographical areas. Seventy percent of focal infections (corresponding to 38% of the total 414 cases) were transmitted within a distance of 200 m (the buffer distance adopted by the national guidelines for insecticide spraying). Two main epidemic clusters were identified, with a radius expanding at a rate of 300–600 m per month. The majority of exported cases resulted in either sporadic or no further transmission in the region. Conclusions Evidence suggest that human mobility contributes to seeding a relevant number of secondary cases and new foci of transmission over several kilometers. Reactive vector control based on current guidelines might allow a significant number of secondary clusters in untreated areas, especially if the outbreak is not detected early. Existing policies and guidelines for control during outbreaks should recommend the prioritization of preventive measures in neighboring territories with known mobility flows to the main areas of transmission. |
| first_indexed | 2024-12-11T10:29:39Z |
| format | Article |
| id | doaj.art-ba733c24bcfd41e98e34f4af396379a1 |
| institution | Directory Open Access Journal |
| issn | 1741-7015 |
| language | English |
| last_indexed | 2024-12-11T10:29:39Z |
| publishDate | 2020-08-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Medicine |
| spelling | doaj.art-ba733c24bcfd41e98e34f4af396379a12022-12-22T01:11:00ZengBMCBMC Medicine1741-70152020-08-0118111010.1186/s12916-020-01674-ySpatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysisGiorgio Guzzetta0Francesco Vairo1Alessia Mammone2Simone Lanini3Piero Poletti4Mattia Manica5Roberto Rosa6Beniamino Caputo7Angelo Solimini8Alessandra Della Torre9Paola Scognamiglio10Alimuddin Zumla11Giuseppe Ippolito12Stefano Merler13Center for Information Technology, Fondazione Bruno KesslerNational Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCSNational Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCSNational Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCSCenter for Information Technology, Fondazione Bruno KesslerCentro Agricoltura Alimenti e Ambiente, Università di TrentoCentro Agricoltura Alimenti e Ambiente, Università di TrentoDipartimento di Sanitá Pubblica e Malattie Infettive, Sapienza University of RomeDipartimento di Sanitá Pubblica e Malattie Infettive, Sapienza University of RomeDipartimento di Sanitá Pubblica e Malattie Infettive, Sapienza University of RomeNational Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCSDivision of Infection and Immunity, Center for Clinical Microbiology, University College LondonNational Institute for Infectious Diseases “Lazzaro Spallanzani” IRCCSCenter for Information Technology, Fondazione Bruno KesslerAbstract Background The spatial spread of many mosquito-borne diseases occurs by focal spread at the scale of a few hundred meters and over longer distances due to human mobility. The relative contributions of different spatial scales for transmission of chikungunya virus require definition to improve outbreak vector control recommendations. Methods We analyzed data from a large chikungunya outbreak mediated by the mosquito Aedes albopictus in the Lazio region, Italy, consisting of 414 reported human cases between June and November 2017. Using dates of symptom onset, geographic coordinates of residence, and information from epidemiological questionnaires, we reconstructed transmission chains related to that outbreak. Results Focal spread (within 1 km) accounted for 54.9% of all cases, 15.8% were transmitted at a local scale (1–15 km) and the remaining 29.3% were exported from the main areas of chikungunya circulation in Lazio to longer distances such as Rome and other geographical areas. Seventy percent of focal infections (corresponding to 38% of the total 414 cases) were transmitted within a distance of 200 m (the buffer distance adopted by the national guidelines for insecticide spraying). Two main epidemic clusters were identified, with a radius expanding at a rate of 300–600 m per month. The majority of exported cases resulted in either sporadic or no further transmission in the region. Conclusions Evidence suggest that human mobility contributes to seeding a relevant number of secondary cases and new foci of transmission over several kilometers. Reactive vector control based on current guidelines might allow a significant number of secondary clusters in untreated areas, especially if the outbreak is not detected early. Existing policies and guidelines for control during outbreaks should recommend the prioritization of preventive measures in neighboring territories with known mobility flows to the main areas of transmission.http://link.springer.com/article/10.1186/s12916-020-01674-yChikungunyaTransmission chainSpatiotemporal spreadTransmission distance |
| spellingShingle | Giorgio Guzzetta Francesco Vairo Alessia Mammone Simone Lanini Piero Poletti Mattia Manica Roberto Rosa Beniamino Caputo Angelo Solimini Alessandra Della Torre Paola Scognamiglio Alimuddin Zumla Giuseppe Ippolito Stefano Merler Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis BMC Medicine Chikungunya Transmission chain Spatiotemporal spread Transmission distance |
| title | Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis |
| title_full | Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis |
| title_fullStr | Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis |
| title_full_unstemmed | Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis |
| title_short | Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis |
| title_sort | spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in italy a modeling analysis |
| topic | Chikungunya Transmission chain Spatiotemporal spread Transmission distance |
| url | http://link.springer.com/article/10.1186/s12916-020-01674-y |
| work_keys_str_mv | AT giorgioguzzetta spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT francescovairo spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT alessiamammone spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT simonelanini spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT pieropoletti spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT mattiamanica spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT robertorosa spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT beniaminocaputo spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT angelosolimini spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT alessandradellatorre spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT paolascognamiglio spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT alimuddinzumla spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT giuseppeippolito spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis AT stefanomerler spatialmodesfortransmissionofchikungunyavirusduringalargechikungunyaoutbreakinitalyamodelinganalysis |