Why is polio a concern in relation to sewage systems?

Polio is a concern in relation to sewage systems because the virus responsible for the disease can survive in untreated wastewater. This resilience in various environmental conditions allows the virus to persist in fecal matter, which can enter sewage systems. When sewage is improperly treated or when contaminated water is released untreated, there is a risk that the polio virus can spread to the community and environment, posing a public health threat. This is particularly critical in areas with poor sanitation and inadequate sewage treatment, as it can lead to outbreaks of polio, especially in populations that are not vaccinated against the virus.

The other options do not accurately address the relationship between polio and sewage systems. While the virus can spread through contact with contaminated surfaces or fecal matter, it is not primarily airborne nor found only in animal waste, nor is it only transmitted in a specific way that excludes waterborne pathways. Understanding that polio can persist in untreated wastewater emphasizes the importance of effective sewage management in preventing disease transmission.