Working with the laboratory

1. Working with the laboratory IDSP training module for state and district surveillance officers Module 6

2. Learning objectives (1/3) • List • L1 and L2 laboratories in the district • L3 laboratories in the state • L4 and L5 laboratories in the country • Understand the need of L1 and L2 laboratories to arrange for logistical support • Identify what action is to be taken be the technician for sample collection in response to the diagnosis made by the medical officer

3. Learning objectives (2/3) • List tests to be performed in L1 and L2 laboratories • Identify quality assurance processes within the laboratory network • Understand bio-safety issues • Identify transport modalities of samples to higher levels

4. Learning objectives (3/3) • Understand training needs of laboratory personnel • Keep track of the flow of samples • Draw a flow diagram for reporting of the laboratory investigations

5. Role of laboratories in disease surveillance • Early diagnosis of diseases under surveillance • Epidemiological investigation • Rapid laboratory confirmation of diagnosis • Implementation of effective control measures

6. Factors influencing laboratory confirmation in surveillance • Advance planning • Collection of appropriate and adequate specimens • Correct packaging • Rapid transport • Ability of laboratory to accurately perform tests • Bio-safety and decontamination procedure

7. Types of case definitions in use More specificity

8. Laboratory network for the Integrated Disease Surveillance Project

9. Risk groups, biosafety levels, practices and equipment

10. Method of laboratory surveillance • Routine passive surveillance • Selected diseases • Outbreak situations

11. Conditions under regular surveillance

12. Other conditions under surveillance

13. Diagnosis of malaria • Laboratory criteria for diagnosis • Detection and identification malaria parasite microscopically • Sample collection for microscopy • Thick and thin blood smear • Time of collection • During fever or 2-3 hours after peak of temperature • Before patient receives anti-malarial

14. Laboratory tasks at each level for the diagnosis of malaria

15. Diagnosis of cholera • Laboratory criteria for diagnosis • Isolation of Vibrio cholera O1 or O139 from stools in any patient with diarrhea • Sample collection • Transfer a portion of specimen to a cotton wool swab • Insert it in alkaline-buffered salt solution • If stool specimen could not be collected take a rectal swab and insert it in the above solution

16. Laboratory tasks at each level for the diagnosis of cholera

17. Diagnosis of typhoid • Laboratory criteria for diagnosis • Serology – Widal or Typhi-dot test positive • Isolation of S.typhi from blood, stool or other clinical specimen • Sample collection • Blood / stool

18. Laboratory tasks at each level for the diagnosis of typhoid

19. Tuberculosis • Laboratory criteria for diagnosis • Demonstration of alcohol-acid fast bacilli in at least two of the three sputum smears or culture positive for Mycobacterium tuberculosis • Sample collection for microscopy • Three specimens • One spot specimen • One early morning specimen (preferably the next day) • One spot specimen when the early morning specimen is being submitted for examination.

20. Laboratory tasks at each level for the diagnosis of tuberculosis

21. Measles • Laboratory criteria for diagnosis • Presence of measles virus specific IgM antibodies • At least four fold increase in antibody titre in paired samples • Isolation of measles virus • Sample collection • Serology • An acute phase serum specimen (3-5ml of whole blood) be soon after onset of clinical symptoms but not later than 7 days • Virus isolation • Urine collected within 5 days of rash onset (1-3days best). • Do not freeze

22. Laboratory tasks at each level for the diagnosis of measles

23. Polio • Laboratory criteria for diagnosis • Isolation of wild polio virus from stool

24. Laboratory tasks at each level for the diagnosis of polio

25. Laboratory criteria for dengue • Isolation of Dengue virus from serum, plasma, leucocytes or autopsy samples • Demonstration of Dengue virus specific IgM antibodies or four fold or more rise in reciprocal IgG antibody titre • Demonstration of dengue antigen in autopsy tissue by Immunochemistry or immunoflourescence or in serum samples by EIA • Detection of viral genomic sequences in autopsy tissue, serum or CSF by PCR One or more of the above

26. Sample collection for the laboratory diagnosis of Dengue

27. Laboratory tasks at each level for the diagnosis of Dengue

28. Laboratory criteria for the diagnosis of Japanese encephalitis • Demonstration of Japanese encephalitis virus specific IgM antibodies • Detection/isolation of antigen/virus • Demonstration of viral antigen in the autopsied brain tissue by the fluorescent antibody test

29. Sample collection for the laboratory diagnosis of Japanese encephalitis

30. Laboratory tasks at each level for the diagnosis of Japanese encephalitis

31. Laboratory criteria for the diagnosis of plague • Gram staining on smear taken from bubo, blood or lung aspirate • Detection of Y. pestis F1* antigen by direct fluorescent antibody testing or by other standardized antigen detection method • Isolation from a clinical specimen • A significant (equal or more than 4-fold) change in antibody titre to the F1 antigen in paired serum specimens * Fraction 1. Glycoprotein from the capsule. Elisa technique

32. Laboratory tasks at each level for the diagnosis of plague

33. Leptospirosis • Laboratory criteria for diagnosis • Isolation from blood or other clinical materials by culture • Positive serology, preferably Microscopic Agglutination Test (MAT) using a panel of Leptospira strains • Sample collection • Blood • During first week of illness collect, second sample to be collected after about a week • Urine • Urine should be collected after second week of illness and transported immediately in sterile container

34. Laboratory tasks at each level for the diagnosis of leptospirosis

35. Laboratory tests for water samples • Most Probable Number (MPN) method for coliform bacteria • H2S strip method for fecal contamination assessment

36. Laboratory tasks at each level for the assessment of water quality

37. Functions of L1 laboratory technicians • Collection of samples for investigations • Perform the laboratory tests assigned to L1 labs • Microscopy for malaria • Microscopy for tuberculosis • Typhi-dot test for typhoid fever • H2S test for water quality • Transport relevant sample to L2 laboratories for culture and serological investigations • Assist Rapid Response Teams in sample collection • Participate in External Quality Assurance conducted by L2 laboratories

38. Functions of L2 laboratory technicians • Perform all tests performed by L1 laboratories • External Quality Assurance for L1 laboratories • Perform the tests assigned to L2 laboratories • Culture and sensitivity for cholera • Serological test for typhoid, Dengue, Leptospirosis • MPN test for water quality • Transport relevant samples to L3 laboratories • Transport 5% of tested samples to L3 for testing and quality assurance • Reporting test results to L1 laboratories for samples received from L1 laboratories • Reporting tests result weekly to district

39. Quality assurance Quality assurance Internal quality control(Continuous, concurrent control of laboratory work) External quality assessment(Retrospective and periodic assessment) + =

40. Internal quality control • Test request and specimen collection • Test processing • Temperature • Reagent • Maintenance of equipment • Reporting and using test results

41. External quality assessment • Within the state IDSP system • L1 by L2 • L2 by L3 • Through external agency • External quality assurance scheme for selected tests

42. Action to be taken by the multi-purpose worker in the field

43. Laboratory investigations by the PHC/CHC medical officer /laboratory technician for Dengue

44. Laboratory investigations by the district and state laboratories for Dengue

45. Laboratory investigations by the PHC/CHC medical officer /laboratory technician for Japanese encephalitis /fever with altered consciousness

46. Laboratory investigations by the district and state laboratories for Japanese encephalitis

47. Laboratory investigations by the PHC/CHC medical officer /laboratory technician for malaria or fever

48. Laboratory investigations by the district and state laboratories for malaria

49. Laboratory investigations by the PHC/CHC medical officer /laboratory technician for cholera /loose watery diarrhea

50. Laboratory investigations by the district and state laboratories for cholera