Chapter 8. Malaria Epidemics detection and response.pptx

Handout for malaria treatment

1. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 1 Malaria Case Management Training for Health Professionals Chapter – 8 MALARIA EPIDEMICS DETECTION AND RESPONSE March 24 Addis Ababa

2. Chapter Introduction Chapter title- MALARIA EPIDEMICS DETECTION AND RESPONSE Duration : 120 minutes Chapter learning objectives : Define malaria outbreak and epidemic Describe the purpose of malaria epidemic forecasting and early warning Explain the basic principles of malaria epidemic detection and response. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 2

3. Chapter Introduction Contd. Chapter Outline/Sessions: Session 8.1. Overview of malaria Epidemic and factors precipitating malaria epidemic, epidemic forecasting, detection, and preparedness Session 8.2. Epidemic confirmation and response Session 8.3. Reporting malaria epidemic 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 3

4. Session 8.1. Overview of malaria Epidemic and factors precipitating malaria epidemic, epidemic forecasting, detection, and preparedness At the end of this session participants will be able to: Differentiate outbreak and epidemic Describe the major malaria epidemics and the current situation in Ethiopia Identify the factors that precipitated malaria epidemic. Recognize the tools used for malaria epidemic detection. Describe the resources needed to handle malaria epidemic when it occurs. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 4

5. Introductory Activity 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 5 Think & Share Please go over the following questions just to retrieve your prior knowledge/experience. What you know about the malaria epidemics in Ethiopia? Describe the current situation of malaria in your area?

6. Definitions Outbreak: increase in number of cases, lasts for only a short time, or occurs only in a limited area Epidemics: is also an excess number of cases , an epidemic is more general than an outbreak, the increase in the number of cases continues far longer, and the cases are distributed across a wider area. 6 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

7. Malaria epidemics Are the occurrence of numbers of cases above what is expected in a place in a particular time period Sometimes it is hard to distinguish malaria epidemics from usual seasonal upsurge of malaria Malaria epidemics can be one of the most serious public health emergencies 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 7

8. Malaria Epidemics Contd. An epidemic could be: An exaggerated seasonal increase An exaggerated "periodic" increase (true /explosive epidemics): An acceleration of a "secular" upward trend: because of neglect/breakdown of control i.e. In non-endemic areas, any transmission (even few confirmed cases) constitutes an epidemic 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 8

9. Cont’d. Rapid increases in the number of cases should be treated as a potentially dangerous epidemic even if the number is within the "expected" level for a specific area and time. Recently the trends of malaria epidemics are more frequent in large scale or small scale in different part of the country 9 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

10. Overview of Malaria Epidemics in Ethiopia A devastating malaria epidemic occurred in 1958, three million cases and 150,000 deaths, covering about 100,000 square miles (259,000 square kilometers) of highland area Since 1958, major epidemics of malaria have occurred at approximately 5-8 year intervals, In 1998, a widespread severe malaria epidemic occurred in most highland as well as lowland areas in the country Amhara and SNNP Regional States, leading to widespread epidemic malaria in highland and highland fringe areas (up to 2,500 meters) in 2003 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 10

11. Self Reflection Activity 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 11 - Objective : To assesse participants Knowledge on Malaria Epidemics. Instructions: Please go over the following questions just to retrieve your prior knowledge/experience. What is your experience in predicting malaria epidemic in your area, how you detect it and preparation you made to handle malaria epidemic

12. Epidemic Detection Malaria epidemics can occur as a result of variability or changes in the rate of infection and population immunity. Generally malaria epidemics occur in places where there is low and unstable transmission, where people have low or no immunity against malaria There could be epidemics in high transmission areas Deterioration of health system, interruption of anti-malarial measures or migration of non-immune individuals, such as population movement in search of labor to these areas. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 12

13. Detection Contd. Other triggering factors include: Unusual local weather phenomena and activities resulting in environmental modification that increase vector population; Increased vulnerability of population from famine and malnutrition; Interruptions of anti-malarial measures which have kept malaria under control; Resistance to anti-malarial medications and/or insecticide used for vector control. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 13

14. Practice Exercise Instructions: Be in group of 4-6, Read and analyze the given scenario and reflect on it . In a kebele the number of malaria cases markedly decreased compared to last year’s same period. However, the case remains to be higher than the threshold. The woreda malaria focal person thinks the problem is because of the threshold calculation. Question: Discuss justify the woreda focal person’s argument Time : 10 min 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 14

15. Epidemic Detection Method 1 is the classic method, based on norm charts and thresholds. This is currently recommended and probably will continue to be used for some time in areas of higher transmission. Method 2 (cluster mapping) will be tested and gradually introduced,   Q:What do you think is the appropriate method to calculate threshold currently in Ethiopia? Discuss your choice 15 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

16. Method 1 To establish a threshold for ‘normal’ for any given week A health facility’s past data by week should be compiled and A threshold determined using the ‘third quartile’ Current data may then be compared with the threshold. If an increase above the weekly threshold is observed, it implies that there may be an epidemic. Under Method 1, an epidemic is defined as: “The occurrence in a health facility catchment area of cases of an illness, clearly in excess of normal expectancy”. 16 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

17. Method 1 Cont’d Definition involves: clear time, place, and person For this we need to know: Where? Which health facility catchment or other defined area When? What time period (“occurrence”) What is “normal expectancy” for that area and time period? What do we mean by “cases” (case definition)? How many of these and what proportion tested have malaria by RDT or microscopy? What is regarded as “excess”? Who has become ill? 17 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

18. Methods Health Post or kebele: - smallest Admin Unit PHCU can use data disaggregated by Kebele /HP Time period : weekly “Monday – Sunday (WHO Calendar versus EFY 28) Normal expectancy: two choices: “Normal”: third Quartile or double the previous year Case definition: “confirmed” or “Presumptive” malaria - use same indicatory 18 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

19. Norm Charts and Thresholds to Detect Epidemics cont. What is necessary to build the Epidemic Monitoring Chart Ready made Epidemic Monitoring Chart or self prepared chart 5 year data of The kebele or Health Center catchment area If there is no 5 years data Use last years data If there is no last years data use recent week’s collected data Woredas use the disaggregated data of Health post and HC data and draw their norm chart or threshold 19 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

20. Threshold Why do we need a threshold? It can be very difficult to distinguish an epidemic from a normal seasonal case increase. Once it is apparent that the seasonal case increase is much higher than normal, the epidemic is well underway. How to calculate the threshold? The following tables give examples of how to tabulate data for estimating a threshold by two methods. The data in the tables is illustrative and for this example only. 20 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

21. Threshold Empty Table Table 18: Chart for assessing usual number of weekly cases (confirmed or clinical) and threshold at health facility. 21 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE WHO Week No. Year 1 Year 2 Year 3 Year 4 Year 5 Third Quartile or second largest number or 2x last year’s cases This year’s cases 1               2               .               .               51               52               (53)              

22. Table… Ppm page#--- 22 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE WHO Week No. Year 1 Year 2 Year 3 Year 4 Year 5 Third Quartile or second largest number or 2x last year’s cases This year’s cases 1 8 42 6 36 14 36 20 2 12 42 27 38 17 38 22 3 10 42 43 49 21 43 35 4 20 17 34 59 32 34 26 5 34 17 46 20 30 34 25 6 18 10 34 22 23 23 20 7 12 19 33 24 25 25 21 8 37 10 27 61 23 37 25 9 32 18 37 29 26 32 16 10 31 24 28 17 13 28 5 11 22 19 22 12 23 22 15 12 17 39 31 22 43 39 25 13 5 19 19 16 21 19 16

23. Table… Ppm page#--- 23 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE WHO Week No. Year 1 Year 2 Year 3 Year 4 Year 5 Threshold (norm) = 2x last year’s cases This Year’s cases 1         14 28 20 2         17 34 22 3         21 42 35 4         32 64 26 5         30 60 25 6         23 46 20 7         25 50 21 8         23 46 25 9         26 52 16 10         13 26 5 11         23 46 15 12         43 86 25 13         21 42 16

24. Self Reflection Objective : To assesse participants Knowledge on Malaria Epidemics. Instructions: Please go over the following questions just to retrieve your prior knowledge/experience. What is one major difference you notice between Table 19 and 20? What do you think is the major reason for this difference? 24 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE

25. Epidemic Preparedness Preparedness includes: Availability of trained human resources, Diagnostics, Anti-malarial drugs, supplies and Insecticides. As a rule, an additional 25% of the annual drug, lab supplies and consumables requirement should be kept as contingency at woreda or health center level. This 25% stock should only be spent when a verified malaria epidemic occurs and needs to be replenished promptly. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 25

26. Session Summary The key principles of epidemic detection and action (using any detection method) are - defining epidemics according to a particular period and area (usually health facility catchment area). The basic unit of time is a week; Epidemics in Method 1 are defined according to a weekly threshold, while Method 2 uses a time window of up to four weeks. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 26

27. Resource & References: WHO, malaria diagnosis and treatment Guidelines, 3rd edition. National Malaria Guidelines, 5th edition, Addis Ababa. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 27

28. Session 8.2 Malaria epidemic confirmation and response Session objective By the end of this session the participants will be able to Demonstrate understanding how to confirm the occurrence of malaria epidemic and Design response for epidemic 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 28

29. Introductory Activity 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 29 Think & Share Take 10 minutes and discuss with a participant sitting near you. When do you need to confirm the presence of malaria epidemic and what are the necessary information you need to collect to confirm it. Also discuss how to respond to a confirmed malaria epidemic.

30. Epidemic confirmation We can confirm epidemics in two ways; Epidemics detected through health facility registers using epidemic charts (Method 1) Assuming that they were based upon RDT, or microscopy confirmed cases. Do not need additional confirmation Epidemics detected by mapping of micro-clusters of cases (Method 2) Assume RDT or microscopy verification and should be handled immediately by HEWs. In both situations, large epidemics will require that microscopy slides be collected for analysis by regional laboratory experts 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 30

31. Response to Malaria Epidemics Whether an epidemic is detected by Method 1 or 2 Active surveillance and other control actions are triggered should continue for up to one month or until no further cases are detected for at least two weeks. If an epidemic is detected, the active surveillance should be as follows: Mass fever testing and treatment (MFTT): Mass presumptive fever treatment (MPFT): Other interventions to be taken simultaneously with MFTT and MPF Treat and refer severe malaria cases request more supplies to replace those consumed SBC for improving LLIN use consider IRS if evidence from epidemiological analysis 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 31

32. Session Summary Epidemics detected through health facility registers using epidemic charts (Method 1) Epidemics detected by mapping of micro-clusters of cases (Method 2) Active surveillance and other control actions are triggered and should continue for up to one month or until no further cases are detected for at least two weeks. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 32

33. Session 8.3 Reporting malaria epidemic Session objective By the end of this session, the participants will be able to: Explain the importance of malaria epidemic reporting. Report malaria epidemic using a systematic reporting format. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 33

34. Introductory Activity 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 34 INDIVIDUAL REFLECTION What do you think is the importance of reporting malaria epidemic?

35. Reporting form for active surveillance and treatment HH No. Total no. of HH members No. of sick (febrile) household members No. of blood samples (RDT or microscopically) examined No. and proportion of positives out of examined (if applicable) Treatment given RDT Microscopy RDT Microscopy   1 2 . . 20 Total Note: Indicate the type of diagnosis, i.e. RDT or microscopy. Then determine fever rate and test positivity rate from the sampled households. Health posts should also report status of malaria supplies inventory. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 35

36. Practice Exercise Instructions: Group Activity 1 Be in group of 4-6 Analyze tables XX Five years data on participant manual page__ contains five year’s weekly data on malaria cases and then answer the questions below it. Question Identify the threshold for each scenario? Draw the chart using the given data? Interpret the result? Time : 20 min 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 36

37. Practice Exercise Instructions: Group Activity 2 Be in group of 4-6 Analyze tables XX Weekly malaria cases 2003–2008 (EFY). on participant manual page__ six year’s weekly data on malaria cases and then answer the questions below it. Question Which year do you think the data shows an abnormally high number of malaria cases? What do you do with this year before you start identifying the second largest number? Identify the second largest number for the six years of data (2003 –2008) and fill in the column in the table. Use the blank epidemic monitoring chart and plot a reference line of the second largest numbers and the data for the year 2009 against it. Does the graph show weeks when an epidemic occurred? If yes, in which weeks? Time : 20 min 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 37

38. Session Summary Reporting is important to supervise the mitigation activities initiated by the health facility. Sample of persons tested and/or treated during the active surveillance must be reported using a random systematic sampling method. If managing the epidemic is beyond the capacity of the health facility, the next higher-level facility should be involved. Once an epidemic is evident at the woreda level, the situation is probably serious and the zone and RHB must be involved. Sever malaria detected at health posts need to be referred to health centers or hospitals immediately. 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE 38

39. Thank You 39 11/03/2024 MALARIA EPIDEMICS DETECTION AND RESPONSE