Malaria Medical Microbiology K R.pptx

Malaria K R.pptx

1. Medical Microbiology Malaria K R MICRO NOTES 1

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3. DR Alphonse laveran Military doctor who discovered the malaria parasite in 1880 K R MICRO NOTES 3

4. INTRODUCTION Malaria is a Mosquito-Borne febrile Disease caused by Malaria Parasites The name malaria was derived from Italian word Mala which means ‘BAD’ and aria means ‘AIR’. It is also known as ‘Ague’ or ‘Marsh fever’. It is widespread in tropical and sub-tropical regions including parts of the Americas, Asia and Africa. The first record of “Periodic fevers” was from China in 2700 BC. It is a disease caused by member of the protozoan genus Plasmodium, a widespread group of sporozoans that Parasites affect the human liver and red blood cells. K R MICRO NOTES 4

5. INTRODUCTION Malaria is found in about 100 countries in the world Maximum Prevalence of Malaria is found in Warm and Humid Environment and mostly seen around July to November in India. Optimal Temperature and Humidity for the development if the Parasite is 20 to 30 F and about 60% Humidity. Humans are infected with Plasmodium protozoa when bitten by an infective Female Anopheles mosquito vector. Symptoms may appear within weeks to months or even years. K R MICRO NOTES 5

6. Female Anopheles mosquito K R MICRO NOTES 6

7. There are 4 species of Malaria Parasites: Plasmodium Falciparum. Plasmodium Vivax. Plasmodium Ovale . Plasmodium Malariae . K R MICRO NOTES 7

8. EPIDEMIOLOGY Precise statistics unknown- most cases are rural. 400 -900 million cases of fever per year. Affects about 515 million people per year. Kills between 1 to 3 million people per year. One death every 30 seconds. K R MICRO NOTES 8

9. EPIDEMIOLOGY Most death occur in children less then 5 years in Sub Sharan Africa (Pregnant women also vulnerable) Plasmodium Vivax is the most common infection (80% of the cases). Plasmodium Falciparum causes most deaths (15% of infections and 90% deaths). Other Plasmodium species also infects birds, reptiles, rodents, monkeys and apes. K R MICRO NOTES 9

10. MOSQUITO VECTORS Primary hosts and transmission vectors are the female Anopheles mosquito. Only the female feed on blood. Mosquito ingests parasite from infected human blood whilst feeding. Carry sporozoites in the salivary glands. K R MICRO NOTES 10

11. LIFE CYCLE Regular and cyclic alteration between asexual and sexual phrases. Asexual phrase - Human (intra corporeal phase). Sexual phase – Mosquito (extra corporeal phase). K R MICRO NOTES 11

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13. INTRA CORPOREAL PHASE Which involves repeating cycles of asexual multiplication (schizogony). Schizogony takes place in 2 stages Liver cells (Liver schizogony). Erythrocytes (Erythrocytic schizogony). Phase begins with inoculation of parasites to human body by mosquito. When an infected mosquito bites a man the parasite ingested to human body called sporozoites. Sporozoites are minute thread like curved forms with tapering ends and an elongated central nucleus. K R MICRO NOTES 13

14. EXTRA CORPOREAL PHASE In the midgut of mosquito ingested human RBC breaks down and release gametocyte. Development cycle of plasmodium in mosquito. It takes 7 to 10 days. Completed in 3 stages- Gamogony Syngamy Sporogony – gut wall K R MICRO NOTES 14

15. TRANSMISSION Natural malaria is induced by sporozoite – infection is transmitted by f.a. mosquito. Transfusion malaria – transfusion of infected donor blood. Malaria in drug addicts – shared syringes in which one of them is infected. Congenital malaria – rarely from mother of foetus. K R MICRO NOTES 15

16. INCUBATION PERIOD Pre- patent Period Time taken from infection to symptomps. Plasmodium falciparum 6-12 days. Plasmodium vivax 10-17 days. Plasmodium ovale 12-16 days. Plasmodium malariae 28-30 days. K R MICRO NOTES 16

17. LABORATORY DIAGNOSIS Laboratory diagnosis of malaria is confirmed by the demonstration of malaria parasites in the blood film under microscopic examination. PERIPHERAL BLOOD SMEAR – GOLD STANDARD Thin film- identifying specific sps. Thick film- to detect the presence of MP. K R MICRO NOTES 17

18. MALARIA BLOOD SMEAR Thin films: Dry Fix Stain Used to determine the species entire thin film should be examined about 20-40 minutes for an experience observer. Thick films: Dry Do not fix but dehemoglobinate Stain Staining methods: Giemsa stain Leishman’s stain Field’s stain K R MICRO NOTES 18

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20. FLUORESCENCE MICROSCOPY Kawamoto technique – fluorescent staining method of demonstrating MP Blood smear are prepared on slides and are stained with acridine orange and examined under F.Microscope – nuclear DNA is stained green. K R MICRO NOTES 20

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22. TREATMENT Treatment of malaria focuses on eradication of the blood parasites Several drugs can be Administrated, such as Chloroquine Quinine Doxycycline Malarone Lariam Fansidar Treatment is dependent on several factors including: Type of malaria Drug-resistance Nearly all strains of P.falciparum are now chloroquine resistant, in addition to developing resistance to nearly all other currently available antimalarial drugs. P.vivax has also developed resistance to chloroquine and primaquine, though they are not as widespread as P.falciparum. K R MICRO NOTES 22

23. MALARIAL VACCINE Vaccines developed are basically of three types: Pre-erythrocytic stage vaccine Blood stage vaccine Transmission blocking vaccine Spf-66 1 st malaria vaccine that was tried in clinical trails in 1990s. RTS,S (Mosquirix)- Most successful vaccine candidate. First effective treatment was the bark of the cinchona tree (contains quinine). Grows in the Peruvian Andes. K R MICRO NOTES 23

24. PROPHYLAXIS Chemoprophylaxis Recommended for travelers going to endemic areas. Drugs used are- Chloroquine/ mefloquine. Vector control strategies Residual spraying- insecticides ( DDT, malathion, fenitrothion) effective against adult mosquito. Individual protection- bed nets, repellents and protective clothing. K R MICRO NOTES 24

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26. Antiviral measures Larvicide- use of mineral oils/ paris green kills mosquito larvae and pupae. Source reduction- environment sanitation, water management and improvement of drainage system. Biological larvicide- Gambusia affinis, guppy and Bacillus thuringiensis. K R MICRO NOTES 26

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28. Refrence FUNDAMENTALS OF MICROBIOLOGY I Edward Alcamo MEDICAL MICROBIOLOGY SATISH GUPTE.MD A TEXT BOOK OF MICROBIOLOGY Dr RC Dubey Dr DK maheshwari https://www.google.com/search q= malaria+slideshare K R MICRO NOTES 28

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