Malaria Diagnosis, Treatment, Prevention

Welcome to Malaria World

Statistics million people infected worldwide million people infected worldwide 1-2 million deaths annually 1-2 million deaths annually Kills over 3,000 children DAILY Kills over 3,000 children DAILY 40% of the world’s population lives in malarious areas 40% of the world’s population lives in malarious areas Major military importance for deployed US forces Major military importance for deployed US forces 1993, Operation Restore Hope, Somalia, Marines fell ill due to non-compliance and bad med intel as to plasmodium species in the area 1993, Operation Restore Hope, Somalia, Marines fell ill due to non-compliance and bad med intel as to plasmodium species in the area 2003, Liberia, Marines and AF Ravens 2003, Liberia, Marines and AF Ravens

Infectious Parasitic Agent Plasmodium ssp. Plasmodium ssp. P. falciparum P. falciparum most lethal, infects all ages of RBC’s most lethal, infects all ages of RBC’s may cause hemolysis of 30% of RBC’s at a time may cause hemolysis of 30% of RBC’s at a time P. malariae P. malariae infects mature RBC’s infects mature RBC’s P. vivax and P. ovale P. vivax and P. ovale relapsing stage in liver relapsing stage in liver infect immature RBC’s infect immature RBC’s

Transmission:  Dusk to Dawn transmission  Transfer of sporozoites from mosquito saliva to human blood Migrate to liver, infect cells and mulitiply Migrate to liver, infect cells and mulitiply Liver cells rupture and release merozoites, which infect and cause rupture of RBC’s Liver cells rupture and release merozoites, which infect and cause rupture of RBC’s

Clinical Signs High fever, headache, chills High fever, headache, chills Anemia, splenomegaly, icterus Anemia, splenomegaly, icterus GI symptoms: nausea, vomiting, diarrhea GI symptoms: nausea, vomiting, diarrhea Periodicity of fever depends on species; almost continuous with P. falciparum Periodicity of fever depends on species; almost continuous with P. falciparum

Clinically severe signs with P. falciparum Cerebral malaria: headache progressing to seizures, impaired consciousness, death Cerebral malaria: headache progressing to seizures, impaired consciousness, death Renal tubular necrosis Renal tubular necrosis Pulmonary edema due to tissue necrosis factor release Pulmonary edema due to tissue necrosis factor release

Patient History Patient History Travel to endemic area: Check the CDC “yellow book” for quick reference Travel to endemic area: Check the CDC “yellow book” for quick reference “Airport malaria” is rare but possible; patient has not been to malarious area “Airport malaria” is rare but possible; patient has not been to malarious area Not on prophlyaxis or not compliant Not on prophlyaxis or not compliant Flu like symptoms may start in country, or weeks, months, or years after leaving area with relapsing forms ( P.vivax and ovale ) Flu like symptoms may start in country, or weeks, months, or years after leaving area with relapsing forms ( P.vivax and ovale )

Diagnosis Gold Standard: Examine multiple blood smears, thick and thin, taken when fever is rising Gold Standard: Examine multiple blood smears, thick and thin, taken when fever is rising Speciation is possible this way Speciation is possible this way “Dipstick” methods based on detecting P. falciparum proteins are used for field screening or confirmatory tests but do not replace the smears. “Dipstick” methods based on detecting P. falciparum proteins are used for field screening or confirmatory tests but do not replace the smears. Expensive; malarious countries can rarely afford Expensive; malarious countries can rarely afford

P. falciparum Delicate rings, multiples, marginalized, double chromatin

P. malariae “Broad band” gametocyte form present, RBC’s not enlarged

P. vivax Thick signet rings, enlarged RBC’s, developing forms

P. ovale “Comet” shaped cells, enlarged RBC’s

Prophylaxis Chloroquine (non-resistant strains) Chloroquine (non-resistant strains) 300 mg base once weekly, begun 2 weeks before travel and continued until 4 weeks after leaving malarious area 300 mg base once weekly, begun 2 weeks before travel and continued until 4 weeks after leaving malarious area Safe for pregnant women; however pregnant women are discouraged from travel to malarious areas! Mosquitoes prefer pregnant women due to skin temp and increased CO2 production. Safe for pregnant women; however pregnant women are discouraged from travel to malarious areas! Mosquitoes prefer pregnant women due to skin temp and increased CO2 production.

Prophylaxis Mefloquine (non-resistant strains) Mefloquine (non-resistant strains) 250 mg weekly, 2 weeks prior, during, and 4 weeks after leaving malarious area 250 mg weekly, 2 weeks prior, during, and 4 weeks after leaving malarious area Can be given on days 1,2,3, and 7, then weekly, if time does not permit patient to start regimen 2 weeks prior. Can be given on days 1,2,3, and 7, then weekly, if time does not permit patient to start regimen 2 weeks prior. Cannot be given to flyers Cannot be given to flyers Side effects: nausea, dizziness, sleep disturbances Side effects: nausea, dizziness, sleep disturbances

Prophylaxis Doxycycline Doxycycline 100 mg SID, 1-2 days prior continuing through 4 weeks after. 100 mg SID, 1-2 days prior continuing through 4 weeks after. OK for flyers with ground test OK for flyers with ground test GI upset and sun sensitivity; yeast infections in women GI upset and sun sensitivity; yeast infections in women

Terminal prophylaxis: Primaquine is only drug that kills the relapsing stage (hypnozoite) of P. vivax and P. ovale in the liver Primaquine is only drug that kills the relapsing stage (hypnozoite) of P. vivax and P. ovale in the liver 23 mg daily for 14 days, upon leaving malarious area. 23 mg daily for 14 days, upon leaving malarious area. Not necessary to take it exactly upon leaving area; if it is missed, make sure it is taken at some point after deployment Not necessary to take it exactly upon leaving area; if it is missed, make sure it is taken at some point after deployment

Prophylaxis Flyers need ground test of doxycycline Flyers need ground test of doxycycline All personnel should have known G6PD status before being given Primaquine. G6PD deficiency can lead to hemolysis. All personnel should have known G6PD status before being given Primaquine. G6PD deficiency can lead to hemolysis. If primaquine use is needed for treatment of malaria infection in G6PD deficiency, use once weekly, mg for 8 weeks If primaquine use is needed for treatment of malaria infection in G6PD deficiency, use once weekly, mg for 8 weeks

Malaria Treatment Drug regimen depends on species of Plasmodium and severity of infection Drug regimen depends on species of Plasmodium and severity of infection Quinine (sulfate or dihydrochloride) Quinine (sulfate or dihydrochloride) Malarone (atovaquone plus proguanil) Malarone (atovaquone plus proguanil) Mefloquine Mefloquine Artemisinins (Chinese traditional tx) Artemisinins (Chinese traditional tx) Primaquine for relapsing species Primaquine for relapsing species

PREVENTION DEET used on skin DEET used on skin Permethrin treated bednets and uniforms Permethrin treated bednets and uniforms Avoid activity dusk to dawn (showering, etc.) Avoid activity dusk to dawn (showering, etc.) Malaria control depends on direct discipline by those in command Malaria control depends on direct discipline by those in command

Good references: Centers for Disease Control and Prevention (CDC) Centers for Disease Control and Prevention (CDC) Control of Communicable Disease Manual Control of Communicable Disease Manual Located with Public Health Located with Public Health National Center for Medical Intelligence (NCMI) National Center for Medical Intelligence (NCMI) Air Force Reporting Instructions Tool (AFRIT) Air Force Reporting Instructions Tool (AFRIT)