A mixed-methods approach to elucidate SARS-CoV-2 transmission routes and clustering in outbreaks in native workers and labour migrants in the fruit and vegetable packaging industry in South Holland, the Netherlands, May to July 2020

Abstract

To obtain insight into SARS-CoV-2 clustering and transmission routes during outbreaks in the predominantly migrant workforce of the fruit and vegetable packaging industry of South Holland, the Netherlands, May to July 2020. Design: This mixed-methods study applied direct observation and interviews, epidemiologic investigation, source and contact data analysis and whole-genome sequencing. Results: We detected 46 SARS-CoV-2 cases and 4 outbreaks with a proportional representation of labour migrant and native workers in 6 unrelated facilities. Complete viral genome sequences revealed at least 3 clusters of native workers and labour migrants, 2 within and 1 between facilities. On-site inspections found adequate implementation of preventative measures to which both native workers and labour migrants showed suboptimal adherence. Being a labour migrant was associated with living in shared housing, but not with more contacts or different sources. Conclusions: The fruit and vegetable packaging industry gave the impression of sufficient preparedness and control. Suboptimal adherence to the facilities' preventative guidelines could have facilitated work floor transmission. Community and household transmission are likely to have contributed to outbreaks. We encourage further research into risk factors for transmission in labour migrants and application of these insights into targeted public health policy.

Health of International Migrant Workers During the COVID-19 Pandemic: A Scoping Review

“…Of the 26 included studies ( 24 – 49 ) almost half (12 of 26) were conducted in Asia ( 24 , 26 , 30 , 32 – 35 , 37 , 41 , 44 , 47 , 49 ) and 8 in Europe. Fourteen papers used a quantitative design ( 24 , 27 , 28 , 30 , 32 , 33 , 35 , 36 , 40 , 42 – 44 , 46 , 48 ), 5 applied mixed methods ( 29 , 31 , 34 , 38 , 45 ) and 23 used primary data sources ( 24 – 29 , 31 , 32 , 34 , 36 – 49 ) ( Table 2 ).…”

“…Other characteristics of the studied populations were often not described in the methodology of the papers: only 9 studies clearly described migrants' length of stay in the host country ( 24 , 27 , 31 , 32 , 37 , 39 , 41 , 43 , 48 ), most of which were long stays (five or more years) and migrants' legal status was not specified in 20 studies ( 26 – 30 , 32 – 34 , 36 , 37 , 39 , 40 , 42 – 49 ). Seven studies had a comparison group ( 29 , 30 , 33 , 35 , 36 , 40 , 45 ), most frequently the majority population (6 of 7 studies) ( 30 , 33 , 35 , 36 , 40 , 45 ). Regarding occupation sectors, most of the migrant population were considered essential workers in sectors related to healthcare (6 of 26) ( 24 , 27 , 31 , 33 , 36 , 39 ) and other essential sectors (11 of 26) ( 25 – 30 , 35 , 38 , 43 , 45 , 46 ) such as agriculture or construction.…”

“…Seven studies had a comparison group ( 29 , 30 , 33 , 35 , 36 , 40 , 45 ), most frequently the majority population (6 of 7 studies) ( 30 , 33 , 35 , 36 , 40 , 45 ). Regarding occupation sectors, most of the migrant population were considered essential workers in sectors related to healthcare (6 of 26) ( 24 , 27 , 31 , 33 , 36 , 39 ) and other essential sectors (11 of 26) ( 25 – 30 , 35 , 38 , 43 , 45 , 46 ) such as agriculture or construction.…”

“…As showed in Table 3 , most of the selected studies found negative outcomes of the COVID-19 pandemic on the health of migrant workers (24 of 26) ( 24 – 29 , 31 – 33 , 35 – 49 ). Fourteen studies described the impact of COVID-19 on migrants' physical health ( 25 , 27 , 28 , 33 , 35 , 36 , 39 – 42 , 44 – 46 , 49 ), 10 studies described COVID-19 outbreaks ( 25 , 27 , 28 , 33 , 35 , 36 , 40 , 42 , 45 , 46 ), and the remaining 4 studies mentioned other physical problems such as headaches, sleeping difficulty, respiratory problems, and chest pain ( 39 , 41 , 44 , 49 ). Fourteen studies assessed the effects of COVID-19 on mental health outcomes, including anxiety, depression, worry, fear, stress, and post-traumatic stress disorder ( 24 , 26 , 29 , 31 , 32 , 37 – 39 , 41 , 43 , 44 , 47 – 49 ).…”

Central and Eastern European migrant worker status, co-living situation and SARS-CoV-2 exposure and transmission risk

“…Temporary contracts with inadequate disability policies incentivise continuing to work while ill. 14 , 17–19 Agency dependency on housing and transportation results in crowded environments with an often changing composition of co-habitants, which has been associated with higher attack rates, higher infection doubling times and more severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections within the social network or household. 16 , 20–23 Observation tells us that companies that depend on migrant workers, from slaughterhouses to warehouses and orchards, have suffered from severe COVID-19 outbreaks throughout the pandemic. 10…”