Whatisglobalhealth?Well,Itisthehealthoftheglobe,Butofcoursewedon

HowGlobalisGlobalHealth?

ByTimWilliams

Whatisglobalhealth?Well,itisthehealthoftheglobe,butofcoursewedon’treallymeanthatbecausetheglobe,orourworld,cangetalongverywellwithouttheproblemscausedbyhumans.Infactifwelookattherealmeaningofglobalhealth,weunderstandthatwhatweshouldactuallybesayingisglobalill-health.Andthatiscausedbyus.

However,weusethephrase‘globalhealth’tomeanthehealthofallthepeopleintheworld,andhowtheirhealthandillnessesinteractwitheveryoneelse.Butthatbringsustotwoquestions;What,exactly,isglobalhealthandwhatareillnesses?

Wemaythinkofglobalhealthasthestudy,researchandpracticethatplacesapriorityonthosehealthissuesthatgobeyondnationalboundariesandgovernments,andisconcernedwithimprovinghealth,andachievingequallevelsofhealth,forallpeopleworldwide.

Theillnessesweshouldconsiderfallintotwomaingroups;infectiousdiseasesandnon-infectiousdiseases.Thecommunicablediseases,knownasCDs(or‘infectious’diseases)arethosethatcanbepassedfromonepersontoanotherperson,andthemostimportantintheworldatthemomentare;respiratoryinfections1,diarrhea2,HIV/AIDS,andmalaria.Thenon-communicablediseases,knownasNCDs(or‘non-infectious’diseases)arethosewhichdevelopinourbodiesbutcannotbepassedontoanyoneelse.Examplesare;ischemicheartdisease3,cerebrovasculardisease4,chronicobstructivepulmonarydisease5,cancer,diabetes,andmanyothers.

Globalhealthisnotlimitedtoloworhighincomecountriesorparticulargeographicalregionsoftheworld,andinmanyplacesintheworldtherearestillmillionsofpeoplelivinginextremepoverty,lackingeventhemostbasicfacilitiessuchascleanwaterandsanitation.Thus,poverty,malnutrition,infectiousdiseasesandreproductivehealtharestillmajorproblems.Somepeoplearefacedwithwarandconflict,othersliveinareaswithoutafunctioninghealthsystem,andhavenoaccesstoaffordablehealthy care.Atthesametime,theagingpopulation,urbanizationandchangingdietsareamongthedriversofanepidemicofnon-communicablediseases,suchascanceranddiabetes,thataffectbothrichandpoor.

Theconcernsofinternationalhealthhavebeenwithusforaverylongtime,infacttheyhavebeenwithuseversincehumansstartedlivinginlargeurbanareasandtravellingtootherlargeurbanareas.Theseurbanareas,smallorlarge,aregenerallydirtyplacesinwhichdiseasecanspreadveryquicklyasaconsequenceofmanypeoplelivingcloselytogether,andas a consequence of poorhygiene.Infact,asaconsequenceofnohygienewouldbeabetterwaytodescribethesituation.

Oneofthefirstglobalhealthproblemswasprobablyplague,alsoknownasthe‘BlackPlague’andthe‘BlackDeath’.PlagueisaverygeneraltermforaninfectiousdiseasethatiscausedbythebacteriumYersiniapestis.Plaguecanbespreadintheair,bydirectcontact,orveryrarelybycontaminatedundercookedfood.Thesymptomsofplaguedependonwhichpartofthebodyisattackedbythebacteria:ifthelymphnodessufferwehavebubonicplague,intheblooditbecomessepticemicplague,andinthelungsitbecomes,pneumonicplague.Theendresultalwaysusedtobethesame:death.Nowadayswehaveantibiotics,abetterunderstandingofhowplagueworks,andverygoodhealthcaresystems.Nevertheless,unlesswemaintainourvigilance,plaguecouldreturn.

Let’slookalittleatthehistoryofplaguesandsomeoftheeffects.Thefirstpandemic,theJustinianPlague,wasnamedafterthe6thcenturyByzantineemperorJustinian1standwasfollowedbyfrequentoutbreaksoverthenexttwohundredyears.Iteventuallykilledovertwenty-fivemillionintheMediterraneanregion.Thesecondpandemic,widelyknownasthe‘BlackDeath’orthe‘GreatPlague’,originatedinChinain1334andspreadalongthetraderoutestoConstantinople(present day Istanbul) andthentoEurope,whereitkilledanestimated60%oftheEuropeanpopulation,aroundtwenty-fivemillionpeople,inthreeyears.Entiretownswerewipedout,andsometimestherewerenotenoughsurvivorsremainingtoburythedead.

Duringthe13thcenturyinSpaintheplaguekilledaroundonemillionpeopleandmanysurvivorsthoughttheJews,wholivedinSpainandEurope,wereresponsible(formanyhistoricalcomplexandfalsereasons).TheresultwasthatJewswereaccusedofpoisoningfood,wellsandstreams. They weretorturedintoconfessingandthen killed,oftenbybeingburnttodeath.TheKingofSpain,AlfonsoXIth,alsodiedfromtheplagueandthisledtoalmosttwentyyearsofcivilwar.Thustheplaguegreatlyaffectedthesocialandeconomicstructureofthecountry,anditsfuturedevelopment.

Thethirdpandemic,theModernPlague,beganinChinainthe1860sandappearedinHongKongby1894.Overthenexttwentyyears,itspreadtoportcitiesaroundtheworld,carriedbyratsontradingships.Thispandemiccausedapproximatelytenmilliondeaths.Duringthislastpandemic,scientistsidentifiedthecausativeagentasabacteriumanddiscoveredthatplaguewasspreadbyinfectiousbitesfromthefleasthatliveonrats.Rat-associatedplaguewassoonbroughtundercontrolinmosturbanareas,andnowadayscanbetreatedwithantibiotics,andcanbepreventedfromspreadingbypromptidentification and treatment.Wecanalsouseinsecticidestocontrolthefleasandthushelpincontrollingplague.

Nowlet’sturntoconsideringmodernaspectsofglobalhealth.Wethinkofhumanhealthinglobaltermsbecausethemanagementofnaturalresourcesandenvironmentalchanges,atbothalocallevelandatanationallevel,haveaneffectonthequalityoflife,onhumanhealthandonthebehaviorofbothCDsandNCDs.Itissometimesscarytoseehowfarmingstrategiesorcityplanningcanhavesignificantpositiveornegativeeffectsonpeoples'livesandhowpoliciescreatedinonecountrycanaffectpeoples'livesinothercountries.

Thesechangesmayinclude;economicchange,themovementofmanypeoplefromoneplacetoanother,thebuildingorextendingofcities,changesinthetypesoffoodthatbecomeavailabletoeat,climatechange,naturaldisasterssuchasearthquakesandtyphoons,war,improvementsinhealthcare,intensificationoffarming,andmanagementofnaturalresources.Forexample,therecentEuropeanDebtCrisis6,aresultofeconomicandpoliticalinfluences,hasseenariseinsuicidesandheartattacksatapopulationlevel,partlyasanoutcomeofausterity,whichwasthepoliticalresponsetoaneconomicproblem.Thusoursocialandeconomicconditionscancontrol;ourriskofillness,theactionswecantaketopreventourselvesbecomingill,andourabilitytotreatillnesswhenitoccurs.

Imagineamiddleagedwomanwhogoestoherdoctorforamedicalexamination,andtheresultisshehasheartdisease.Whatcouldbethecauses?Biologicallyitmaybetoomuchcholesterolinherdiet,orpossiblyobesitywhichledhertoherdisease.Butwhatfactorswhereinvolved?Whatisherlevelofhealthknowledge?Whatwerehercopingandhealthpractices?Whatbiologicalorgeneticpredispositionsdidshehave?Whataboutherchildhood,andtheenvironmentinwhichshegrewup?Herincomeandsocialstatus,education,andemploymentopportunities?Whatsocialsupportsdidshehavetoavoidthedisease?Alltheseconsiderationswillbeimportant,indifferingdegrees,toherhealthstatus.

Inlow-incomecountriesweseehugedifferencesbetweenruralandurbancommunitiesinrelationtotheirdiseaseburdens.Thecommonchildhood-relatedinfectiousdiseasesaremalaria,pneumonia,diarrhea,HIVandothers,andaremajorcausesofchilddeath.In low-income countries onlyafewadultswillsufferfromNCDssuchasdiabetesandheartdiseases.Butsincemanychildrendieatanearlyage,theoveralllifeexpectancyinaruralcommunitymaybebelowfiftyyears.Incontrast,afewkilometersuptheroad,wemayfindatypicalurbansetting.Thechildmortalitymaybefairlylow,whereasdiabetes,highbloodpressureandheartdiseasesarecommonamongadults,andoveralllifeexpectancyis60, 65yearsoreven higher.Thisdoubleburdenofdiseasemayevenexistwithinthesamegeographicalarea,orevenwithinthesamefamilywherewecouldseeanoverweightmotherwithhighbloodpressureanddiabetes,whereasherlastbornchildisseverelyanaemicandunderweightandsuffersfromrepeatedattacksofmalaria.Soverydifferentdiseaseburdensmaycoexistinthesamegeographicalsetting.

In this photo from the Philippines, weseemiddle-classair-conditionedapartmentblockssurroundedbyverypoorhouseholds.Themiddleclassindividualsintheirapartmentswillnotsufferfromthesamehygiene-relatedinfectiousdiseasesastheirlessfortunateneighborsinthecityslums.Ontheotherhand,thefamilieswholiveintheapartmentswillprobablyhaveahigherintakeofcaloriesandlowerlevelsofphysicalactivity,andamuchhigherriskofbeingoverweightcomparedtotheirneighbors.Andallofthishappenswithinafewhundredmeters.Inmanylow-incomecountriesitisthewealthierpartofthepopulationthathasamuchhigherriskofNCDscomparedtosub-populationswithlowercalorieintakesandhigherlevelsofwork-relatedphysicalactivity.Onecouldsaythatthelessfortunatesub-populationscannotaffordthelifeconditionsthatincreasetheirriskofNCDs.SointhissettinginthePhilippinestheassociationbetweensocio-economicstatusandNCDsisprobablystraightforward.Thehighersocio-economicstatus,thehigherriskofNCDs.

However,inafewyearswewillprobablyseethatthewealthierandbettereducatedgroupsintheapartmentblocks,willbemoreawareoftheirlifeconditionsand,moreimportantly,havethepowerandopportunitytochangethis.SotheriskofNCDswilldeclineinthisgroup.WhereastheirpoorerandlesseducatedneighborsmayhaveimprovedtheirincomeandcannowaffordthevariousNCD-relatedriskfactors,suchastobacco,alcohol,highercalorieintakeandlesswork-relatedphysicalactivity.

Tosummarize;asaresultoflongerlifeexpectancies,causedbylowerdeathrates,whicharearesultofmodernization,urbanization,economicdevelopment,improvedwaterandsanitationandimprovedhealthsystems;andasaresultofchangesinlivingconditions,whichoftenwillresultinchangesindiet,lessphysicalactivityandhigherintakeofalcoholandtobacco;thediseaseburdensrelatedtoinfectiousdiseaseswilldecrease,whiletheproblemsofNCDswillincrease.

Urbanizationisnotbad,butitcomeswithriskstoourhealthwhichmustbemanaged.Solet'srecap.Thewaywelive,ouraccesstoeducation,employment,qualityhousing,andasafecleanlivingenvironment,plusotherfactors,haveastrongeffectonglobalhealth.Bothintermsoftherisksofdevelopingnon-communicablediseases,andinaccessingtreatmentsafterwebecomeill.

Notes

1 – respiratory infections: any of a number of infectious diseases involving any part of the breathing system, i.e. the nose, throat, trachea and lungs. Infections such as bronchitis, pneumonia, tuberculosis (TB), H5N1 can lead to death, and in the past influenza (flu) was also a killer.

2 – diarrhea (UK spelling diarrhoea): is the condition of having loose or liquid bowel movements (defecation). It often lasts for a few days and can result in dehydration due to fluid loss. If not treated, this can lead to death. The most common cause is an infection due to either a virus, bacteria, or parasite. These infections are often acquired from food or water that has been contaminated by feces, or directly from another person who is infected.

3 – ischemic heart disease: this occurs when a part of the heart does not receive enough blood, and leads to a ‘heart attack’ and often death.

4 – cerebrovascular disease: disease of the blood vessels that supply oxygen to the brain. This commonly leads to a stroke and paralysis or death. High blood pressure is the most important cause.

5 – chronic obstructive pulmonary disease: a disease of the lungs in which there is restricted air flow. The main symptoms include shortness of breath and coughing with sputum production, Eventually even walking up stairs or carrying things becomes difficult. Tobacco smoking and air pollution are common causes.

6 –

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