The binding legal principles established are: (1) In business interruption insurance policies covering notifiable diseases, a government response (whether local or national) to such a disease forms part of the insured peril itself, not merely a consequence separate from the peril. This is because notifiable diseases by their nature pose public health risks requiring governmental action. (2) A geographic radius requirement (such as 50 km) in a notifiable disease clause operates as a qualifying threshold for coverage and a limit against liability for remote occurrences, but does not restrict coverage only to responses by local authorities or responses limited to that geographic area. Where a notifiable disease occurs within the specified radius and contributes to a wider governmental response (including national measures), coverage is triggered. (3) For causation in such policies: (a) factual causation is established where the local occurrence of the disease and the government's response (properly understood as forming the composite insured peril) would not have resulted in business interruption but for that occurrence and response; (b) where there are concurrent causes (local and national outbreak), the proximate cause is determined by reference to reality, predominance and efficiency, applying business common sense; (c) legal causation (remoteness) is assessed primarily by reference to the policy provisions rather than general policy considerations applicable in delict. (4) Insurance contracts must be interpreted objectively by reference to language, context and purpose to ascertain what parties must be taken to have intended, not what they subjectively thought. The fact that parties did not specifically contemplate a pandemic does not exclude coverage if the policy language, properly construed, encompasses such events. (5) The "trends clause" or "other circumstances" clause used for quantifying loss does not operate to negate liability where the circumstance relied upon (government regulations) forms part of the insured peril itself.