This new third edition provides updated information about microbes that are spread from person to person and the diseases they cause, including influenza, lice infestation, pneumonias, staphylococcal and streptococcal infections, tuberculosis, and others. The types of diagnostic tests and treatments available from medical professionals are explained, and self-care practices for familiar symptoms are described. Other topics addressed include antibiotic resistance, the role of handwashing in preventing the spread of disease, and recommendations and controversies surrounding vaccination programs. The book concludes with a glossary of related terms and a directory of additional resources.