Microbiology and Aging

Theworld’spopulationisestimatedtoreach8. 9billionby2050with370million peopleof80yearsofageorolder. Ageingisanincurablediseaseandde?nedasthe ’deregulationofbiochemicalprocessesimportantforlife’,butforthepurposeof this book, ageing is better de?ned as the biological process of growing older. Ageingispartofnaturalhumandevelopment. Asyouwillseethroughoutthisbook,themicrobiologicalburdenonthehostis enormousandclinicallysigni?cant,andwillundoubtedlyhavearoletoplayinthe ageing process. As humans are living longer, there is a greater propensity to infection. This risk is substantially heightened in elderly individuals who are predisposedtoinfection. Whiletheprocessofageinganditseffectsonthehost’s microbiology are poorly documented and researched, data obtained from gut studieshaveshownthatmicrobiologicalchangestakeplaceovertimesuggesting signi?cancetothehost. Dothemicrobiologicalchangesthatoccurwithinandupon thehostin?uencetheprocessofageingorisitthebiologicalchangesofthehost thataffectsthemicrobiology?Doesthisthereforeaffectourpropensitytodisease? Asthehost’smicrobiologychangeswithageing,isthissigni?cantlybene?cialor severelydetrimentaltothehost?Aretherewaysofenhancinglifeexpectancyby reducingcertainbacteriafromproliferatingorconverselybyenhancingthesurvival ofbene?cialbacteria? Thisbookconsidersthemicrobiologyofthehostindifferentregionsofthebody andhowthesevaryinthedifferentagegroups. Chapter1ofthebookfocuseson ageingtheorieswithChap. 2consideringthehumanindigenous?oraandhowthis isaffectedduringageing. Chapter3highlightsthemaininfectionsassociatedwith anelderlypopulation,whileChap. 4reviewstheprocessofskinageingandits associatedmicrobiology. Chapter5reviewstheageinglungandChap. 6reviews in?uenzaintheelderly. Chapter7highlightsthechangesthatoccurintheoral micro?ora and host defences with advanced age with Chap. 8 reviewing the in?uenceofthegutmicrobiotawithageing. Chapter8focusesonthegutandits associatedimmunity. Theremainingfourchaptersofthebookconsiderclostridium andtheageinggut,Helicobacterpyloriandthehygienehypothesisandthebene?ts of probiotics. The microbiology theory of autism in children is reviewed in vii viii Preface Chap. 13. The?nalchapterofthebookexamineshowthebene?cialmicrobiology ofthehostleadstohumandecomposition. Thisbookencompassesacollectionofreviewsthathighlightthesigni?canceof andthecrucialrolethatmicroorganismsplayinthehumanlifecycle. Flintshire,UK StevenL. Percival Contents 1 AgeingTheories,DiseasesandMicroorganisms. . . . . . . . . . . . . . . . . . . . . . . . . 1 StevenL. Percival 2 IndigenousMicrobiotaandAssociationwiththeHost. . . . . . . . . . . . . . . . . 15 JohnG. ThomasandStevenL. Percival 3 InfectionsintheElderly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 KnutOhlsen,SvitlanaKozytska,andUdoLorenz 4 SkinAgingandMicrobiology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 LeslieBaumann,EdmundWeisberg,andStevenL. Percival 5 LungInfectionsandAging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 SameerK. MathurandKeithC. Meyer 6 In?uenzaintheElderly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 CaterinaHatzifotiandAndrewWilliamHeath 7 ChangesinOralMicro?oraandHostDefences withAdvancedAge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 RimondiaS. Percival 8 In?uenceoftheGutMicrobiotawithAgeing. . . .