**4. Discussion**

With support from the LMPHU vaccination outreach team, many farms across the region were prepared for this pandemic and ensured that cases did not have severe outcomes. The outer regional and remote areas of Australia had virtually no COVID-19 in 2020 and the first half of 2021 due to government-imposed lockdowns. The rapid response teams involving the local pathology service, cultural and language support services, and farm management enabled adequate risk assessment and allowed for farm work to continue in the face of the outbreak. Even though the initiative to allow asymptomatic workers to continue working was not the norm for all outbreaks, it has also been reported elsewhere with favourable outcomes [16].

Although the viral genomics were not performed to identify the VoC in this outbreak, confirmation with PCR was important to understand the severity of the outbreak and negate the low sensitivity for the RAT as per DH guidelines [3]. Once established, followup tests for contacts were performed by RAT, and all who tested positive were considered probable cases. Although the outbreak coincided with the peaking of the Omicron VoC in the country, in this rural town, it is difficult to ascertain whether the causative agent was Delta or Omicron as infections have historically shown a delay compared with the more populated metropolitan regions. The high infectivity and low symptom severity may point towards a possible Omicron VoC as the causative agent [17–19].

In this case report, the farmworkers were managed by contractors and initially worked across different farms. Yet, they lived together in the farm's accommodation camps where they shared facilities. This added another layer of complexity in contact-tracing and efficient communication between the farm management and contractors in identifying close contacts between different farms. However, after multiple site contact-tracing and testing, all contacts that lived elsewhere were able to quarantine in their homes, further reducing the risk of spread. No new cases or exposures were generated from these contacts. Other risks in this outbreak were mainly due to the timing coinciding with the peak of the Omicron COVID-19 VoC and the collapse of the pathology PCR testing capacity across the country. The RATs were introduced; however, the reporting system was not yet live online until the outbreak was well underway. Another challenge in managing this outbreak was that it occurred in a CALD group with low levels of written and spoken English. This proved a barrier to reading the provided instructions for responding to the outbreak, such as testing; reporting of RAT results; and compliance with isolation, quarantine, and appropriate facemask requirements. Furthermore, migrant populations

have significantly higher proportions of undiagnosed co-morbidities and do not have access to many government support initiatives, such as Medicare, that promote equitable access to healthcare [20,21], which was reinforced during the COVID-19 pandemic [22].

Colignan is an outer regional town on the banks of the Murray River located at least 40 min from the rural city of Mildura where the main public hospital, testing, and vaccination clinics are located. Its remote location provides excessive challenges with access to healthcare. This cohort experienced barriers including the limited provision of appropriate local health options, limited transport, and fear of accessing services in many instances. The migrant farmworkers did not have Medicare cards, and whilst they did have private insurance, there were concerns expressed about the out-of-pocket costs they would incur should they need to access healthcare. Further communication barriers made it difficult to ensure that public health orders were complied with and testing requirements with RATs were correctly performed. As the case numbers were increasing during the outbreak, organising food and accommodation for effective isolation and quarantine became challenging.

Engagement with the farm management and cultural support for overcoming communication barriers was important for gaining trust between the LMPHU and workers who were living through a COVID-19 outbreak. The introduction and delivery of RAT kits further helped alleviate the challenges with PCR testing, which, at this point, had turnaround times not ideal to make useful public health actions. Although RATs are generally considered to have lower sensitivity to detect infections [23,24], they are regarded as a vital public health tool for the management of outbreaks [3]. The LMPHU has now engaged the services of an outer regional coordinator who will work hand-in-hand with key stakeholders such as community health services to specifically target more farms in the Mildura region for coordinated vaccination programs.
