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This presentation is prepared as part of the Course assignment of “Epidemiology of Diseases and Health Problems” for the Master's Degree of Public Health (MPH), Pokhara University and can be used as reference materials. The content and facts included in the presentation are as of information available till December 2022 and no conflict of interest is associated with the presentation. The presentation is prepared by Sagar Parajuli.

This presentation is prepared as part of the Course assignment of “Epidemiology of Diseases and Health Problems” for the Master's Degree of Public Health (MPH), Pokhara University and can be used as reference materials. The content and facts included in the presentation are as of information available till December 2022 and no conflict of interest is associated with the presentation. The presentation is prepared by Sagar Parajuli.


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Epidemiology of Malaria & Dengue_Sagar Parajuli.pptx

  1. 1. Epidemiological Perspective of Malaria and Dengue & Review of National programs and activities Sagar Parajuli MPH Second Semester 2022 School of Health & Allied Sciences Pokhara University
  2. 2. 2/7/2023 2 Presentation Outlines • Introduction (Malaria & Dengue) • Epidemiological Determinants (Agent, Host and Environment) • Distribution (Global, Regional, National) • Prevention, Control and Treatment Activities • Response towards Malaria and Dengue (WHO & Government of Nepal); National policies and programs review Presentation followed by discussion
  3. 3. 2/7/2023 3 Introduction to Malaria (ICD 11, 1F40-1F4Z) • Etymologically, the term malaria derived as Italian word as mala-bad, aria- air is a protozoan infection, dominantly in tropics and sub-tropics • Acute febrile illness, caused by Plasmodium parasites spread by bite of an infected female Anopheles mosquito • Plasmodium 5 species- P. falciparum, P. ovale, P. vivax, P. malariae, P. knowlesi-zoonotic malaria • P. falciparum known as deadliest malaria parasite (malignant tertian) and P. vivax as dominant malaria parasite poses the greatest threat of malaria (benign tertian)
  4. 4. 2/7/2023 4 Epidemiological Determinants • Agent: Plasmodium parasites, 5 species • Vector: Female Anopheles Mosquito ‘invertebrate definite host’ • Host Factors: Human as ‘intermediate host’ and ‘reservoir’ as well 1. Genetic Factors: Biological advantage for people having sickle cell trait, thalassemia, G6PD deficiency to P. falciparum, people with duffy blood type to P. vivax 2. Immunological Factors: Newborn of mother infected with malaria developing acquired immunity for first few months of birth 3. Behavioral factors Risk population: living in endemic and slum areas, pregnant women, traveler, children
  5. 5. 2/7/2023 5 Epidemiological Determinants • Environmental Factors: vital for vector and parasite growth and development, as well as for creating contact environment between agent, host and vector 1. Climate-based factors: rainfall 2. Temperature- 16-34 Degree Celsius with optimal transmission at 25 3. Precipitation; frequency, duration and intensity 4. Waste water management, breeding places like damp and waterlogged Peak season and months: May-July, September-December following end of dry and wet season, dominant during rainy season due to waterlogged and damp places suitable for mosquito breeding
  6. 6. 2/7/2023 6 Transmission Dynamics • Mode of transmission: ‘Bite, Blood, Birth’ Through bite of an infected female Anopheles mosquito (during dusk, early night hours, early morning hours), Blood Transfusion & share of needles, vertical transmission to lesser extent ‘congenital malaria’ • Incubation Period: 7-14 days for P. falciparum, 8-14 days for P. vivax and P. ovale, 7-30 days for P. malariae • Period of Communicability: as long as infective gametocytes present in blood; not more than a year for P. falciparum, 1-2 years for P. vivax and P. ovale, 7 months-3 years for P. malariae (EWARS Guideline)
  7. 7. 2/7/2023 7 Natural History of Malaria
  8. 8. • Mosquito stage (Sporogonic cycle) • Human Liver stage (Exo-erythrocytic cycle) • Human Blood stage (Erythrocytic cycle) 2/7/2023 8 Plasmodium Life Cycle
  9. 9. • Intermittent Periodic fever; a characteristic paroxysmal malarial fever with ‘cold, hot, and wet’ phases, usually after 10-15 days of mosquito bite • Headache, Vomiting, Chills • Anemia, Splenomegaly • Dry (Nonproductive cough) Symptoms repeat 48-72 hrs in a cyclic manner. Based on symptoms and complications, malaria categorized as uncomplicated and complicated (severe) malaria. 2/7/2023 9 Clinical presentations
  10. 10. Diagnosis • Microscopy ‘Gold Standard’; Thick and Thin smear • RDT • Serological Test Complications • Anemia • Cerebral Malaria • Others; liver failure, jaundice, ARDS, kidney failure, shock, pulmonary oedema • Complications during pregnancy 2/7/2023 10 Diagnosis & Complications
  11. 11. 2/7/2023 11 Global Status- Malaria • Globally, estimated 247 million cases in 2021 from 84 malaria endemic countries, increased from 245 million cases in 2020 • Malaria case incidence globally- 59 cases per 1000 population at risk • 29 countries accounted for 95% malaria cases globally; Nigeria (27%), Democratic Republic of Congo (12%) • South East Asia accounted for 2% burden of malaria globally, with 76% case reduction and 82% reduction in case incidence, case incidence reported in 2021- 3 cases per 1000 population at risk Source: Global Malaria Report, WHO 2020
  12. 12. Malaria Microstratification 2021, Annual Report- DoHS 078/79 • 22 High Risk Wards • 69 Moderate Risk Wards • Malaria risk shift to upper hilly river valley • 82% high risk burden and 94% of moderate risk burden concentrated in Karnali and Sudurpaschim 2/7/2023 12 National Status- Malaria Source: DoHS Annual Report 077/78
  13. 13. 2/7/2023 13 National Status- Malaria Source: Malaria Surveillance Guideline 2019
  14. 14. 2/7/2023 14 National Status- Malaria Source: Malaria Surveillance Guideline 2019
  15. 15. 2/7/2023 15 National Status- Malaria 0 200 400 600 800 1000 1200 2075/76 2076/77 2077/78 1069 619 377 440 102 66 625 517 311 Indigenous and Imported Malaria Cases Total Positive cases Indigenous cases Imported cases • 90 % reduction in Indigenous Malaria Cases in FY 077/78 compared to FY 71/72 • Annual Blood Examination Rate (ABER) decreased to 1.32 % • Annual parasite incidence rate-0.03 per 1000 population, slide positivity rate- 0.24% • 86.47 % P. vivax cases • 13.52 % P. falciparum cases • High malaria cases reported in Kailali, Kanchanpur, Banke, Achham, Surket and Baitadi Source: DoHS Annual Report 077/78
  16. 16. 2/7/2023 16 Global Malaria Control Activities •Era • Period • Major achievement Era Period Major achievement Eradication 1955-1969 Malaria control by Insecticide Spray Resurgence 1969-mid 1980 Establishment of microscopic center and treated by sign and symptoms Control 1980 onwards Research activities, IRS, Medical Recording Roll back 1998 onwards Epidemic control, surveillance strengthening, Elimination strategy
  17. 17. 1950 • 2 Million cases (40% of total population) and 10-15 % Deaths 1954 • IBDCP; started malaria control activities, with support of USAID (USOM) 1958 • Malaria Eradication Program; first national public health program 1978 • Redefined and revised as ‘Malaria Control Program’ 1993 • Adopted WHO supported Global Malaria Eradication Strategy (GMCS) 1998 • Roll back malaria (RBM) launched, initially in 12 endemic districts 17 Chronological Activities: Malaria Eradication to Control, Nepal
  18. 18. • National Malaria Laboratory Technical Steering Committee & TWG- EDCD, NPHL, VBDRTC • Health Office as focal point at district level • Malaria Microscopy Center Testing service at HP, PHCCs, Primary Hospital • PACD, RACD & Community-based testing as per necessity 2/7/2023 18 Institutional Framework Source: National Malaria Laboratory Plan
  19. 19. • Case Notification, Surveillance and Information System: Reporting through DHIS 2, MDIS, EWARS (Immediate reporting of single case of severe and complicated malaria), within 24 hrs and 74 hrs action 1. Case-based surveillance 2. Integrated Entomological Surveillance 3. Vector survey • Case Identification and Detection: Case investigation, Foci investigation, PACD, RACD & Community-based testing as per necessity • Risk mapping: Micro-stratification • Prevention & Promotion activities: Distribution of LLIN, ITN, Development of IEC and SBCC materials, celebration of Malaria Day 2/7/2023 19 National programs and activities
  20. 20. • Capacity building of HSPs and stakeholders: Palika level, district level, women group focused, FCHVs focused • Research: Operational research on malaria, vectors and parasites • Interventions: Vector control interventions • System strengthening: Supportive supervision • Specific activity for imported malaria: Testing at PoEs/GC (Point of Entry and Ground Crossing) 2/7/2023 20 National programs and activities
  21. 21. • Malaria Disease Information System (MDIS); developed by Ekbana for EDCD for Malaria Control Program • In operation, for case notification and analysis through two systems; mobile application and CMS system 2/7/2023 21 MDIS- A short brief
  22. 22. 1. Case Investigation Form; Mobile application 2. Case Notification 3. Data Analysis 2/7/2023 22 MDIS- A short brief
  23. 23. 2/7/2023 23 Surveillance Framework
  24. 24. Vision: Malaria Elimination in Nepal by 2025 Mission: Ensure universal access to quality assured malaria services for prevention, diagnosis, treatment and prompt response in outbreak. Goal: Reduce the indigenous malaria cases to zero by 2022 and sustain thereafter. Objectives: To ensure proportional and equitable access to quality assured diagnosis and treatment in health facilities as per federal structure and implement effective preventive measures to achieve malaria elimination 2/7/2023 24 National Malaria Strategic Plan (2014-2025) Surveillance & Information System Vector Control Intervention Early Diagnosis and treatment Leadership & Community engagement Strengthening technical and managerial capacities
  25. 25. 2/7/2023 25 WHO Response towards Malaria • WHO Committee: MPAG, VCAG, TAG-MEC • Development of ‘Global Technical Strategy for Malaria (2016-2030)’- technical framework for all malaria endemic districts Target: Reduce case incidence and malaria mortality by 90% in 2030 Eliminate malaria in at least 35 endemic countries by 2030 • Global Malaria Programme; providing technical support and assistance to country programs • SDG Target 3.3: “By 2030, end the epidemics of AIDS, tuberculosis, malaria and neglected tropical diseases and combat hepatitis, water-borne diseases and other communicable diseases.”
  26. 26. • ABCD strategy; Awareness, Bite prevention, Chemoprophylaxis, Diagnosis • Surveillance; Identification, detection and treatment • Preventive chemotherapies: PMC, SMC, IPTp, IPTsc, PDMC, MDA • Interventions: Vector-control, IVM, IRS • Health Promotion; Use of LLIN, ITNs • Health Education • Specific Protection: Vaccine (recommended from October 2021) RTS,S/AS01 malaria vaccine 2/7/2023 26 Prevention, Control and Management
  27. 27. Sagar Parajuli MPH Second Semester 2022 School of Health & Allied Sciences Pokhara University Epidemiological Perspective of Dengue & Review of National programs and activities
  28. 28. 2/7/2023 28 Introduction to Dengue (ICD 11, 1D20-1D2Z) • An acute mosquito-borne arboviral disease caused by dengue virus (DENV), dominantly found in tropical and sub-tropical regions • Transmitted through bite of an infected Aedes mosquito, mainly by Ae. aegypti and to lesser extent by Ae. albopictus • Dengue virus (DENV) are of 4 serotypes; DEN-1, DEN-2, DEN-3, DEN-4 • Infection with one serotype gives lifelong immunity to that serotype but only short-term immunity to other serotypes (cross-immunity is partial and temporary) • Subsequent infection increases risk of severe dengue fever. Severe Dengue first time reported in 1950 during epidemic in Philippines and Thailand
  29. 29. 2/7/2023 29 Epidemiological Determinants • Agent: Dengue Virus; DEN-1, DEN-2, DEN-3, DEN-4, RNA virus of Flaviviridae • Vector: Female Aedes aegypti Mosquito ‘invertebrate primary vector’ anthropophilic nervous feeder and Aedes albopictus as ‘secondary vector’ aggressive feeder • Host Factors: Human as ‘intermediate host’ and ‘reservoir’ as well, can occur at any age irrespective of sex, in endemic areas • Environmental Factors: Climatic factors (rainy, summer and spring), rainfall, temperature and humidity. 16 ͦ C - 30 ͦ C temperature and the relative humidity of 60- 80%. Risk population: living in endemic areas, pregnant women, traveler, children
  30. 30. 2/7/2023 30 Transmission Dynamics • Mode of transmission: ‘Bite, Blood, Birth’ 1. Through bite of an infected female Aedes mosquito (daytime feeder; early in the morning 2hrs after sunrise, evening before sunset), 2. Blood Transfusion & share of needles, 3. Vertical transmission to lesser extent (perinatal transmission and peripartum maternal infection) 4. Transovarial transmission reported among vectors as well • Incubation Period: ranges from 3-14 days, typically 5-7 days • Period of communicability: No person to person transmission, 3-5 days before end of febrile period and 8-12 days mosquito after viremic blood meal
  31. 31. 2/7/2023 31 Incubation period Dengue
  32. 32. 2/7/2023 32 Infection Cycle
  33. 33. • Dengue cases ranges from asymptomatic to mild to severe. An estimated 1 in 4 dengue virus infections are symptomatic.(CDC) • Undifferentiated dengue fever • Classic dengue fever ‘breakbone fever’ (Fever, headache, muscle and join pain, nausea, vomiting, rash after 4-5 days of fever, hemorrhagic manifestations) • Dengue Hemorrhagic Fever (DHF); bruises, epistaxis, gum and GI bleeding • Dengue Shock Syndrome; Hypotension Approximately 1 in 20 patients with dengue virus disease progress to develop severe dengue. (CDC) 2/7/2023 33 Clinical presentations
  34. 34. 2/7/2023 34 Dengue Categorization Dengue Virus Infection Symptomatic Undifferentiated Dengue (Without Hemorrhage) Dengue Fever (With Hemorrhage) Dengue Hemorrhagic Fever (with plasma leakage) DHF with Shock DHF without Shock Expanded Dengue Syndrome Asymptomatic
  35. 35. 2/7/2023 35 Dengue Categorization National Guideline on Prevention, Management and Control of Dengue in Nepal
  36. 36. 2/7/2023 36 Clinical presentations; phases Febrile phase (2-7 days, can be biphagic): Sudden onset of fever accompanied by headache, retro-orbital pain, generalized myalgia and arthralgia, flushing of the face, anorexia, abdominal pain and nausea, Rash on the trunk, on the medial aspect of the arms and thighs, and on plantar and palmar surfaces Critical phase (24-48 hrs): Begins with defervescence, Persistent vomiting and severe abdominal pain , Increasingly lethargic, weakness, dizziness or postural hypotension occur during the shock state, spontaneous mucosal bleeding Increasing liver size and a tender liver is frequently observed, rapid and progressive decrease in platelet count, plasma leakage Convalescent phase: Plasma leakage subsides and begins to reabsorb extravasated intravenous fluids, hemodynamic status stabilizes
  37. 37. Diagnosis • Virological test • Serological test RDT, RT-PCR Complications • DHF • DSS • Liver, Kidney damage • Multi-organ damage • Bleeding & respiratory distress 2/7/2023 37 Diagnosis & Complications
  38. 38. 2/7/2023 38 Global Status- Dengue • Globally estimated 100-400 million infections occurs per year • 80% mild and asymptomatic • Dengue cases increased by 8 fold in last two decades • Dengue Epidemic in more than 100 countries (before 1970 only in 9) • Highest cases in 2019 Source: WHO Factsheet 2022
  39. 39. 2/7/2023 39 Global Status- Dengue • In 2020/21, Dengue reported from Asia, Africa, America, Caribbean, and Pacific region. • Five countries with highest cases 1. Brazil 2. Paraguay 3. Mexico 4. Vietnam 5. Malaysia Source: WHO Factsheet 2022
  40. 40. 2/7/2023 40 South East Asia Status- Dengue Categories A Bangladesh, India, Indonesia, Maldives, Myanmar, Sri Lanka, Thailand, Timor-Laste 1. Major Public Health Problem 2. Leading cause of hospitalization and death among children 3. Hyperendemicity with all 4 Serotypes circulating in urban areas 4. Spreading to rural areas Categories B Bhutan, Nepal 1. Endemicity Uncertain 2. First reported case in Bhutan and Nepal Categories C DPR Korea 1. No evidence of endemicity • South East Asia accounts for more than half burden of dengue in the world. • From 2015 to 2019, dengue cases in SEA region increased by 46% whereas deaths decreased by 2% (WHO)
  41. 41. Trend of Dengue cases in Nepal (2004-2022) • Dengue first reported in 2004 in Nepal • DENV1 and DENV2 contributing to Dengue Outbreak in Nepal (EDCD 2019) • Outbreak reported mostly during September • January-September 2022, CFR 0.13% 2/7/2023 41 National Status- Dengue Trend Source: Dengue situation Report 2022, EDCD
  42. 42. 2/7/2023 42 National Status- Dengue 2022 #Situation Report Dengue, EDCD 2022 • Total National cases: 54232 • Highest no of cases reported from Bagmati, Lumbini and Province 1 • Bagmati cases -78.2% and 68.4 % deaths (WHO 2022) Source: Dengue situation Report 2022, EDCD
  43. 43. 2/7/2023 National Status- Dengue 2022 43 Source: Dengue situation Report 2022, EDCD
  44. 44. 2/7/2023 44 National Status- Dengue 2022 Number of Dengue cases reported from districts of Nepal from 1 January- 28 September 2022.
  45. 45. Goal: To reduce the morbidity and mortality due to dengue fever, dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) Objectives • To develop an integrated vector management (IVM) approach for prevention and control • To develop capacity on diagnosis and case management of dengue fever, DHF and DSS • To intensify health education and IEC activities • To strengthen the surveillance system for prediction, early detection, preparedness and early response to dengue outbreaks 2/7/2023 45 National Dengue Control Program
  46. 46. • Case Notification, Surveillance and Information System: Reporting through DHIS 2, EWARS (Immediate reporting of single case of clinical dengue), within 24 hrs 1. Case-based surveillance 2. Entomological Surveillance (A. aegypti identified in 5 peri-urban areas of terai; Kalilali, Chitwan, Parsa, Dang and Jhapa) • Case Identification and Detection: Dengue testing at Health Facilities & Community-based testing as per necessity, Mobilization of RRT • Risk mapping and identification of population at risk • Prevention & Promotion activities: Development of IEC and SBCC materials, Distribution of LLIN and IBN 2/7/2023 46 National programs and activities
  47. 47. • Capacity building of HSPs and stakeholders: Palika level, district level, women group focused, FCHVs focused • Research: Operational research on dengue, vectors and parasites • Interventions: Vector control interventions (search and destroy) • System strengthening: Supportive supervision 2/7/2023 47 National programs and activities
  48. 48. • Case Definition; Dengue without warning signs, with warning signs, severe dengue (WHO classification) • Case Definition; suspected, probable, confirmed • Surveillance categories 1. Passive Disease surveillance 2. Enhanced Disease surveillance 3. Syndromic surveillance 4. Sentinel surveillance and active case finding 5. Vector surveillance 2/7/2023 48 Surveillance for Dengue
  49. 49. 2/7/2023 49 Govt. Response to Dengue Control in 2022
  50. 50. 2/7/2023 50 WHO Response towards Dengue • supports countries in the confirmation of outbreaks • provides technical support and guidance to countries for the effective management of dengue outbreaks • provides training on clinical management, diagnosis and vector control • formulates evidence-based strategies and policies • support countries in the development of dengue prevention and control strategies and adopting the Global Vector Control Response (2017-2030) • publishes guidelines and handbooks for surveillance, case management, diagnosis, dengue prevention and control for Member States.
  51. 51. Level of actions recommended as per National Guideline on Prevention, Management and Control of Dengue in Nepal • Household level; Use of personal protection measures, mosquito repellants and tight fitting mesh/screens on windows and doors, elimination of mosquito breeding in and around the house • Community level; Community awareness program, basic sanitation measures, eliminating outdoor breeding sites, promoting use of insecticide treated nets to • Institutional level; Early case detection and treatment, source elimination activities, notification of fever case (suspected/confirmed), entomological surveillance 2/7/2023 51 Prevention, Control and Management
  52. 52. • Chemical Control • Biological control • Environmental management; modification, manipulation, change in human habitation or behavior 2/7/2023 52 Prevention, Control and Management A vaccine to prevent dengue (CYD-TDV, Dengvaxia®) is licensed and available in 20 countries for people ages 9–45 years old. The World Health Organization recommends that the vaccine only be given to persons with confirmed prior dengue virus infection. (CDC)
  53. 53. 2/7/2023 53 Prevention, Control and Management
  54. 54. • National Malaria Strategic Plan (2014-2025) • Malaria Laboratory Manual 2021 • Microstratification of Malaria in Nepal • National Malaria Laboratory plan (2020-2025) • National Malaria Surveillance Guideline 2019 • National Malaria Treatment Protocol 2019 • Interim guidance for continuing malaria services during COVID19 pandemic in response to 40% mean reduction in malaria testing (Source: Interim guidance for Malaria services in COVID19) • National Guideline on Prevention, Management and Control of Dengue in Nepal, 2019 • Global strategy for Dengue prevention and control 2021- 2030 2/7/2023 54 Guiding Documents
  55. 55. 1. Castro, M. C. (2017). Malaria Transmission and Prospects for Malaria Eradication: The Role of the Environment. Cold Spring Harbor Perspectives in Medicine, 7(10), a025601. 2. CDC. (2021, September 13). Dengue Clinical Presentation | CDC. Centers for Disease Control and Prevention. 3. Huang, H.-W., Tseng, H.-C., Lee, C.-H., Chuang, H.-Y., & Lin, S.-H. (2016). Clinical significance of skin rash in dengue fever: A focus on discomfort, complications, and disease outcome. Asian Pacific Journal of Tropical Medicine, 9(7), 713–718. 4. Midekisa, A., Beyene, B., Mihretie, A., Bayabil, E., & Wimberly, M. C. (2015). Seasonal associations of climatic drivers and malaria in the highlands of Ethiopia. Parasites & Vectors, 8, 339. 5. Nguyen, N. M., Kien, D. T. H., Tuan, T. V., Quyen, N. T. H., Tran, C. N. B., Thi, L. V., Thi, D. L., Nguyen, H. L., Farrar, J. J., Holmes, E. C., Rabaa, M. A., Bryant, J. E., Nguyen, T. T., Nguyen, H. T. C., Nguyen, L. T. H., Pham, M. P., Nguyen, H. T., Luong, T. T. H., Wills, B., … Simmons, C. P. (2013). Host and viral features of human dengue cases shape the population of infected and infectious Aedes aegypti mosquitoes. Proceedings of the National Academy of Sciences of the United States of America, 110(22), 9072. • 2/7/2023 55 References
  56. 56. 6. Nishiura, H., & Halstead, S. B. (2007). Natural History of Dengue Virus (DENV)—1 and DENV—4 Infections: Reanalysis of Classic Studies. The Journal of Infectious Diseases, 195(7), 1007–1013. 7. Prevention, C.-C. for D. C. and. (2020, July 16). CDC - Malaria—About Malaria—Biology. 8. Rijal, K. R., Adhikari, B., Adhikari, N., Dumre, S. P., Banjara, M. S., Shrestha, U. T., Banjara, M. R., Singh, N., Ortegea, L., Lal, B. K., Thakur, G. D., & Ghimire, P. (2019). Micro-stratification of malaria risk in Nepal: Implications for malaria control and elimination. Tropical Medicine and Health, 47(1), 21. 2/7/2023 56 References
  57. 57. 2/7/2023 57 Thank you!

Editor's Notes

  • For more: Falciparum malaria is potentially life-threatening. Patients with severe falciparum malaria may develop liver and kidney failure, convulsions, and coma. Although occasionally severe, infections with P. vivax and P. ovale generally cause less serious illness, but the parasites can remain dormant in the liver for many months, causing a reappearance of symptoms months or even years later.
    A certain species of malaria called P. knowlesi has recently been recognized to be a cause of significant numbers of human infections. P. knowlesi is a species that naturally infects macaques living in Southeast Asia. Humans living in close proximity to populations of these macaques may be at risk of infection with this zoonotic parasite.
    P. vivax and P. ovale have stages (“hypnozoites”) that can remain dormant in the liver cells for extended periods of time (months to years) before reactivating and invading the blood. Such relapses can result in resumption of transmission after apparently successful control efforts, or can introduce malaria in an area that was malaria-free
  • Vector: Anopheles masculatus, An. Annularis, An. Minimus,
  • For more information: The parasites have a tougher time developing when mosquitoes are too warm. But if a mosquito picks up the parasites from blood at around dusk, those parasites have more hours of cooler nighttime temps to complete their development.
  • Source: Annual Report, Department of Health Services
  • For information: MPAG: Malaria Policy Advisory Group, VCAG: Vector Control Advisory Group
  • PMC- Perennial Malaria Chemoprevention, SMC- Seasonal Malaria Chemoprevention, Intermittent preventive treatment of malaria in pregnancy (IPTp) and school-aged children (IPTsc), post-discharge malaria chemoprevention (PDMC) and mass drug administration (MDA)
  • .
  • Source:,febrile%2C%20critical%2C%20and%20convalescent.