Malaria PDF

Malaria: Malaria remains a significant threat in tropical and subtropical regions. Caused by Plasmodium parasites, it's transmitted by female Anopheles mosquitoes. Despite progress, resistance and complications pose ongoing challenges. by Muayad Baheer Malaria-Causing Parasites 1 P. falcip...

Malaria: Malaria remains a significant threat in tropical and subtropical regions. Caused by Plasmodium parasites, it's transmitted by female Anopheles mosquitoes. Despite progress, resistance and complications pose ongoing challenges. by Muayad Baheer Malaria-Causing Parasites 1 P. falciparum 2 P. vivax Most dangerous species, Can cause relapses due to causing severe dormant liver stages. complications. 3 P. ovale 4 P. malariae Similar to P. vivax, with Can persist for years with potential for relapses. occasional recrudescence. Global Malaria Burden 2018 1 228 million clinical malaria cases worldwide, 93% in Africa. 2 2010-2018 Decline in global malaria incidence due to WHO prevention and treatment campaigns. 3 Present Emergence of artemisinin resistance, particularly in Southeast Asia. Malaria Life Cycle: Mosquito Stage Gametocyte Ingestion 1 Mosquito feeds on infected human blood containing gametocytes. Mosquito Development 2 Parasites develop in mosquito for 7-20 days. Sporozoite Formation 3 Sporozoites accumulate in mosquito salivary glands. Malaria Life Cycle: Human Stage Liver Invasion 1 Sporozoites enter liver cells within 30 minutes of inoculation. 2 Merozoite Release Liver stage parasites release merozoites into bloodstream. 3 Red Blood Cell Invasion Merozoites invade red blood cells, beginning asexual multiplication. Hypnozoites and Relapse P. vivax P. ovale Forms dormant liver stages Also capable of producing called hypnozoites. hypnozoites. Relapse Risk Hypnozoites can activate months or years later, causing clinical malaria. Pathology of Malaria Haemolysis Cytoadherence Organ Damage Infected red blood cells rupture, causing P. falciparum-infected cells stick to Vessel congestion and toxin release lead anemia. blood vessel walls. to organ dysfunction. Evolutionary Impact of Malaria 1 Sickle Cell Trait 2 Thalassemia Provides protection against severe P. falciparum malaria. Another genetic adaptation offering some malaria resistance. 3 G6PD Deficiency 4 Duffy Antigen Confers partial protection against malaria infection. Absence protects against P. vivax infection in some populations. Clinical Features of Malaria Fever Headache Often the first symptom, may have Common symptom in early stages of specific patterns. infection. Vomiting Fatigue Gastrointestinal symptoms are General malaise and weakness are frequent. typical. P. falciparum Malaria Complications Cerebral Malaria Severe Anemia Can cause coma and Rapid destruction of red blood neurological deficits. cells. Acute Kidney Injury Pulmonary Edema Renal dysfunction due to Fluid accumulation in lungs parasite effects. causing breathing difficulties. Malaria in Pregnancy Increased Risk 1 Pregnant women are more susceptible to severe malaria. Placental Binding 2 Parasites preferentially bind to placental protein chondroitin sulphate A. Fetal Complications 3 Can lead to abortion, intrauterine growth retardation, and stillbirth. Malaria Diagnosis: Microscopy Thick Film Thin Film Giemsa Stain Used for detecting low-level Confirms species and quantifies parasite Standard staining method for malaria parasitemia. load. parasites. Rapid Diagnostic Tests (RDTs) 1 OptiMAL 2 Parasight-F Detects Plasmodium LDH for Identifies P. falciparum P. falciparum and P. vivax. histidine-rich protein 2. 3 Advantages 4 Limitations Quick results, useful in Less sensitive for low remote areas. parasitemia, may remain positive after treatment. Molecular Diagnosis PCR Research Use Recrudescence vs Highly sensitive method for detecting Primarily used in research settings. Reinfection malaria parasites. Helps distinguish between parasite recurrence types. Treatment: Artemisinin-based Combination Therapy (ACT) First-line Treatment WHO recommends ACT for uncomplicated P. falciparum Artesunate-amodiaquine malaria. Another common ACT combination. 1 2 3 Co-artemether Combination of artemether and lumefantrine. Severe Malaria Treatment Intravenous Artesunate Quinine First-line treatment for severe malaria. Alternative when artesunate is unavailable. Supportive Care Monitoring Management of complications is crucial. Close observation for treatment response and side effects. Non-falciparum Malaria Treatment Species First-line Treatment Additional Treatment P. vivax Chloroquine Primaquine (radical cure) P. ovale Chloroquine Primaquine (radical cure) P. malariae Chloroquine None Malaria Prophylaxis Chloroquine Atovaquone-proguanil Used in areas without chloroquine Effective in many regions, including resistance. chloroquine-resistant areas. Doxycycline Mefloquine Alternative for chloroquine-resistant Used in areas with multiple drug regions. resistance. Vector Control Strategies Insecticide-Treated Nets Indoor Residual Spraying Larval Source Management (ITNs) Application of insecticides to interior Targeting mosquito breeding sites to Provide physical and chemical barrier walls of homes. reduce vector population. against mosquitoes. Intermittent Preventive Treatment (IPT) Pregnant Women 1 Regular doses of antimalarials during pregnancy. Infants 2 Prophylactic treatment during routine vaccinations. Children 3 Seasonal malaria chemoprevention in high-transmission areas. Malaria Vaccine Development RTS,S/AS01 1 First malaria vaccine recommended by WHO for pilot implementation. R21/Matrix-M 2 Promising candidate showing high efficacy in early trials. Future Prospects 3 Ongoing research for more effective and long-lasting vaccines. Drug Resistance Challenges Chloroquine Resistance Artemisinin Resistance Widespread in many malaria- Emerging threat, particularly in endemic regions. Southeast Asia. Multidrug Resistance Surveillance Complicates treatment and Ongoing monitoring of drug prevention strategies. efficacy is crucial. Malaria in Travelers 1 Risk Assessment 2 Prophylaxis Consider destination, Appropriate medication duration, and activities. based on travel plans. 3 Bite Prevention 4 Post-Travel Vigilance Use of repellents, protective Seek medical attention for clothing, and bed nets. fever within 3 months of return. Special Populations: Children High Risk Diagnosis Challenges Treatment Considerations Children under 5 are particularly Symptoms can be non-specific in young Dosing and drug choice may differ from vulnerable to severe malaria. children. adults. Malaria in Pregnancy Increased Susceptibility 1 Pregnant women are at higher risk of severe malaria. Fetal Risks 2 Malaria can cause low birth weight and stillbirth. Prevention Strategies 3 IPT and ITNs are crucial for protecting pregnant women. Economic Impact of Malaria Healthcare Costs Productivity Loss Significant burden on health Absenteeism and reduced work systems in endemic countries. capacity due to illness. Educational Impact Economic Growth School absenteeism affects Malaria slows economic growth in children's learning and highly endemic countries. development. Global Malaria Elimination Efforts 1 WHO Global Technical Strategy Aims to reduce malaria cases and deaths by 90% by 2030. Country-specific Programs 2 Tailored approaches based on local epidemiology and resources. Cross-border Initiatives 3 Collaboration between countries to prevent malaria spread. Future Directions in Malaria Control Gene Drive Technology New Drug Development Potential to modify mosquito Research into novel populations to reduce antimalarials to combat transmission. resistance. Improved Diagnostics Integrated Approaches Development of more sensitive Combining multiple strategies and specific tests. for more effective control. Community Engagement in Malaria Control Health Education Community Health Workers Raising awareness about malaria Training local individuals to provide prevention and treatment. basic malaria services. Participatory Approaches Feedback Mechanisms Involving communities in designing Ensuring community input is and implementing control strategies. incorporated into program improvements. Malaria Surveillance and Monitoring Case Detection Data Management Response Planning Active and passive surveillance to Use of digital systems to collect and Using surveillance data to guide identify malaria cases. analyze malaria data. targeted interventions.