1 Table of Contents: “...Introduction: The changing microbial environment, Darwinian medicine and the hygiene hypothesis...”

2 Table of Contents: “... with essential hygiene -- Chapter 3. Biodiversity, microbiomes, and human health -- Chapter 4. Regulation of host...”

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4 Table of Contents: “... in rats exposed by inhalation -- V — Implications in Industrial Hygiene and in Public Health --...”

5 “... in developing countries, with limited hygienic facilities, bad water supplies and sanitation. Infection is also...”