!!!!!1939!–!Paul!Hermann!Müller!discovered!insec7cidal!!proper7es!of !DDT!!!!!!!!!(Dichloro>diphenyl>trichloroethane)!!!!!!!!!!!!!!!Widely!available!2nd!half!of!WWII!Inspired!by!two!watershed! events:!Persistent,!cheap!and!safe!(?)!insec7cide!!1934!Discovery!of!Chloroquine!by!Bayer:!!• !found!to!be!effec7ve!an7>malarial!in!1946!by!Bri7sh!!!!!and!US!scien7sts!• !cheap,!effec7ve,!(rela7vely)!liRle!or!no!side!effects!!Global!Malaria!Eradica7on!Campaign!(1955>1969)!1#!• !Early!successes!in!malaria!eradica7on!in!US,!Europe ,!se emed!to!put!global!malaria!eradica7on!within! reach!Malaria#in#Europe#disappeared#because#of:###Improved#drainage#and#reclama9on#of#swamps####Increase#in#farm#animals,#but#people#lived##################no#longer#in#very#close#associa9on#with#them#–>#less##contact#with#the#vectors#that#feed#to#large#extent#on#animals####Changes#in#living#condi9ons#####Improvement#medical#care#####An9Dmalarial#drugs####Deliberate#mosquito#control#Global!Malaria!Eradica7on!Campaign!(1955>1969)!2#The!tools!!• !IRS:!Indoor!Residual!Spraying!with!DDT!!• !Distribu7on!of!Chloroquine!!!!(Most!of!sub>Saharan!Africa!was!provisionally!excluded)!>>!few!encouraging!results!in!early!African!malaria!control!efforts.!!Global!Malaria!Eradica7on!Campaign!(1955>1969)!3#The!Results:!Brazil:!!1950’s !5!million!cases!a!year!!!!!!!!!!!!!!1960’s! !50,000!cases!a!year!!India: !!1945 !75!million!cases,!800,000!deaths!!!1968!!! !!no!deaths!recorded!!• !Malaria!disappeared!from:!!US,!Japan,!Korea,!Taiwan,!Spain,!Italy,!the!Balkans,!Greece,!Northern!Africa!!• !Also,!major!reduc7ons!in!malaria!in!Asia!and!South!America!Global!Malaria!Eradica7on!Campaign!(1955>1969)!4#DDT!resistance!Resistance!to!DDT!became!widespread!in!mosquitoes!!• !Metabolic!resistance!• !Knockdown!resistance!(KDR)!!• !Behavioral!Resistance!Chloroquine!resistance!Chloroquine#resistance#emerged#in#P.#falciparum#in#the#late#1950’s#What#happened#next?#5#Malaria!was!not!eradicated!from!much!of!the!tropics!!!!!!!!!!!!Eventually,!campaign!abandoned:!!!!!!!!!!!Chloroquine!resistance!!!!!!DDT!resistance!!!! ! !!!!Donor!fa7gue!!!!!!War!and!Civil!unrest!!!!Global!resurgence!in!malaria:!!e.g.,!!India ! !1976 !6.45!million!cases!Brazil ! !1991 !700,000!cases!Campaign!was!considered!a!failure!by!many,!!but!saved!tens!of!millions!of !lives!!!Followed!by!period!of!low!!interest!in!malaria!control!(1970s!–!1990s)!Global!Malaria!Eradica7on!Campaign!(1955>1969)!6#Malaria!cases!vs.!DDT!spraying!Only#several#10’s#of#malaria#cases,#why#keep##spending#money#on#keeping#up#control?#Here#is#why!#7#The!last!15>20!years!has!seen!renewed!interest!in!malaria!control:!• !Roll!Back!Malaria!Ini7a7ve!(1998):Partnership!between!!!UNICEF,!UNDP,!WHO,!World!Bank.!“In!2015!malaria!!!should!no!longer!be!a!major!cause!of!mortality!or!!!barrier!to!social!and!economic! g rowth!anywhere!in!world”!!• Global!Fund!(2002):!Public/Private!partnership!with!!!funding!of!US$!11.4!billion!for!more!than!550!!!programs!in!136!countries!(AIDS,TBC,!Malaria)#• !The!President’s!Malaria!Ini7a7ve!(2005):!!US!Government!ini7a7ve!designed!to!cut!malaria!mor tality!in!half !!in!target!countries!($1.2!billion!ove r !5!years)!!• !Private!sector:!Gates!founda7on,!Marathon!Oil!Corpora7on!It# is# now# widely# realized# that# we# cannot# effec9vely# improve# the#economies#of#developing#countries#without##reducing#the#burden#of#infec9ous#disease.#8#Global#malaria#control#spending#in#1998:#$100#million/year####9#Required vs available funding 10#Currently!Artemesinin!Combina7on!Therapies!are!used!in!all!African!countries!(Chloroquine:!Approx.!cost!for!treatment!$0.10)!The!Main!Tools:!1)!Case!Detec7on!and!manageme nt!11#The!Main!Tools:!2)!Vector!Control!A) Indoor#Residual#Spraying#(IRS):#####needs#to#be#repeated#every#4D6#months######D>#large#logis9cal#undertaking####Insec9cides#used:###Pyrethroids,#Carbamates#####(resistance#against#both#is#already#present)###B)#Insec9cide#treated#nets#(ITN)############D>##retreat#every#6#months##########LongDLas9ng#Insec9cide#Treated#Nets######(LLITN)######D>#Last#3D5#years####12#Annual#child#(<5)#malaria#deaths#prevented#An#es9mated#750,000#children’s#lives#were#saved#in#the#last##decade#by#increased#control#efforts#The#Result#13#Effect!of!Development!Projects!on!Malaria!Economic#development#projects#that#increase#mosquito#popula9ons,#like#irriga9on#and#dams#can#both#increase#and#decrease#malaria#rates#in#local#popula9ons#2#Kou#Valley,#Burkina#Faso#######################(May) ####(October)##Irrigated#village: # #16% ###########58%#NonDirrigated#village: # #35% ###########82%#1#Tigray#region,#Ethiopia#7Dfold#higher#incidence#of#malaria#cases#near#microdams#Why#the#difference#between#1#and#2?##Infec9on#rate:#The#impact#on#malaria#transmission#of#a#development#that#increases#mosquito#popula9ons#depends#a#lot#on##what#happens#to#the#local#economy.#D>#if#economy#improves#people#can#protect#themselves#14#As the review of studies has shown and as depicted in Fig-ure 2, the impact of irrigation schemes or a large dam site onmalaria depends on several contextual determinants sincepersonal protective measures, access to effective treatment,and acquired immunity factors strongly counterbalance nega-tive effects. Although studies on large dam sites in sub-Saharan Africa are rare, we can conclude that irrigation pro-jects and dam sites in general might not present a risk toinhabitants of stable malaria areas, in particular when controlprograms have been launched simultaneously. It has recentlybeen estimated that approximately 10% of the African popu-lation lives in epidemic, unstable, malaria risk areas.26Wetherefore assume that currently approximately 0.9 millionpeople live near irrigation and large dam sites in unstablemalaria transmission areas. Without the implementation ofmalaria control programs, inhabitants, particularly youngchildren, in these settings are at high risk of disease-associated morbidity and mortality. Since the irrigated area insub-Saharan Africa is anticipated to increase strongly, in par-ticular in arid and semi-arid environments, this number islikely to increase significantly.Southeast Asia (WHO sub-regions 11 and 12). In contrastto WHO sub-regions 1 and 2, irrigated agriculture plays amuch greater role in southeast Asia: 10.6% of the total sur-face area is currently irrigated, mainly for rice production.The irrigated area is expected to further grow