MALARIA

1. MALARIA

2. What is Malaria? • You know it. Well done. • And for those who think they know little about malaria, follow us for next 35 minutes and go through your book at home.

3. MALARIA THE PARASITE

4. Plasmodium falciparum • Plasmodium vivax • Plasmodium ovale • Tropical Africa • Plasmodium malariae • Karnataka

6. MALARIA THE VECTOR

7. Some species • An. culicifacies • An. fluviatilis • An. stephensi • An. minimus • An. philippinensis • An. sundaicus • An. maculatus

8. Factors which determine vectorial importance of mosquitoes • DENSITY • Critical density- below which effective transmission cannot be maintained in a community • An. culicifacies- high density • An. fluviatilis- low density • LIFE SPAN

9. CHOICE OF HOST • Anthrophilic species like An. fluviatilisare better vectors of malaria than zoophilic species • RESTING HABITS • Endophily • Exophily • BREEDING HABITS • TIME OF BITING • RESISTANCE TO INSECTICIDES

10. MALARIA THE DISEASE

11. Reservoir of infection • Human reservoir • Harbors the sexual forms (gametocytes) of the parasite • P. malariae • Chimpanzees in tropical Africa

12. A patient can be a carrier of several plasmodia species at the same time • Children are more likely to be gametocyte carriers than adults. The child is thus epidemiologically a better reservoir than the adult.

13. Conditions that must be met before a person can serve as a reservoir • Both male and female gametocytes are present in blood • Gametocytes are mature • Gametocytes are viable • Gametocytes are present in sufficient density to infect mosquitoes (at least 12/cumm of blood)

14. Period of communicability • As long as mature, viable gametocytes exist in circulating blood in sufficient density

15. Mode of transmission • Vector transmission • Direct transmission • Congenital malaria

16. Incubation period • Falciparum • 12 (9-14) • Vivax • 14 (8-17) • Ovale • 17 (16-18) • Malariae • 28 (18-40)

17. Clinical features • Signs and symptoms • Complications • Cerebral malaria • ARF • Liver damage • GI symptoms • Dehydration • Collapse • Anemia • Blackwater fever

18. Anemia • Splenomegaly • Enlargement of liver • Herpes • Renal complications

19. MALARIA GLOBAL SCENARIO

26. Every minute 2 people die of malaria. By the time we will finish this lecture malaria would have killed180 more people.

27. MALARIA SOUTH-EAST ASIA REGION

33. MALARIA PREVENTION & control

34. A. Malaria Vector Control • Integrated Vector Management (IVM) • Indoor Residual Spraying (IRS) • Insecticide Treated Nets (ITNs) • Other methods • Larviciding • Environmental management approaches to vector control • Personal protection measures (includes ITNs) • Fogging or area spraying Integrated vector management (IVM) is a rational decision-making processfor the optimal use of resourcesin the management of vector populations, so as to reduce or interrupt transmission of vector-borne diseases.

35. INSECTICIDES Organo-Chlorines DDT Organo-Phosphates Malathion,Abate, Fenthion, Chlorpyrifos Carbamates Propoxur, Carbaryl Synthetic pyrethroids Tetramethrin, Resmethrin, Allethrin

36. B. Diagnosis • Direct Microscopy • RDTs (Rapid diagnostic tests)

37. Histidine-rich protein-2 (HRP2) • Parasite-specific lactate dehydrogenase (pLDH)

40. C. Treatment Chloroquine25 mg/Kg over 3days PLUS Primaquine0.25 mg/kg BW daily for 14 days CQ Sensitive Vivax ACT PLUS Primaquine0.25 mg/kg BW daily for 14 days CQ Resistant ACT PLUS Primaquine0.75 mg/kg BW single dose Falciparum Severe Malaria ParenteralArtemesinin derivatives/Quinine Followed by full course of ACT

41. Plasmodium vivax cases • Day 0: T. Chl 10 mg/kg BW (600 mg adult dose) • Day 1: T. Chl 10 mg/kg BW (600 mg adult dose) • Day 2: T. Chl 5 mg/kg BW (300 mg adult dose) • PLUS • T. Primaquin 0.25 mg/kg BW daily for 14 days

42. ACT (Artesunate Combination Therapy) • T. Artesunate 4mg/kg BW daily X 3days • PLUS • T. Sulphadoxine 25 mg/kg BW and T. Pyrimethamin 1.25 mg/kg BW on the first day • Resistance to Chloroquine and ACT • Oral Quinine 10 mg/kg BW and T. Doxycycline 100 mg daily for 3 days THEREAFTER T. Primaquin 0.75 mg/kg BW single dose

43. Artesunate 2.4 mg/Kg BW IV or IM at 0, 12 & 24 hrs, then daily • Artemether 3.2 mg/Kg BW at 0, then 1.6 mg.Kg BW per day • Quinine 20 mg salt/Kg BW at 0 (IV infusion), then 10 mg/Kg BW every 8 hrs

44. D. Intermittent Preventive Treatment

47. E. Malaria vaccines

48. Pre-erythrocytic vaccines • Blood-stage vaccines • Transmission-blocking vaccines • Pfs25 • Cocktail vaccines • SPf66

49. F. Chemoprophylaxis • Travelers from non-endemic areas • Soldiers serving in highly endemic areas • Migrant labourers • Should be complemented by personal protection and environmental measures • Intermittent preventive treatment in pregnancy

50. For short-term prophylaxis (< 6 weeks) • Doxycycline 100 mg X OD in adults or 1.5 mg/kg BW for children >8 years old. • Started 2 days before travel and continued for 4 weeks after leaving the malarious area. • Contraindicated in pregnant females and children <8 years. • For long-term prophylaxis (>6 weeks) • Mefloquine 5 mg/kg BW (upto 250 mg) weekly • Started 2 weeks before travel and continued till 4 weeks of leaving the malarious area. • Contraindicated in cases with H/O convulsions, neuropsychiatric problems and cardiac conditions.