A Great Islamic scolar Ibnal Qayyaum R A

• A Great Islamic scolar , Ibn-al Qayyaum R. A said: the things that make the body sick are: Too much! talking, Too much sleeping, Too much Eating

laboratory diagnosis of infectious diseases • Bacteriologic • Immunologic(serologic) • Molecular (nucleic acid–based) tests

Koch, s postulates • Organism must be present in lesions in every case of disease • Possible to isolate org in pure culture • Inoculation of pure culture in lab animal should produce disease • Possible to reisolate the org

MICROBIOLOGICAL DIAGNOSIS • • • Multi-step process Clinician- patient meeting Specimens – quality of specimens is crucial Specimen from sterile sites- enrichment media Specmen from a site with a normal floraselective media to supress the growth of commensal organisms

MICROBIOLOGICAL DIAGNOSIS • • • Specimen choice Apropriate specimens Containers –labelled sterile containers Transport – Specimen quality control –result depend on quality of specimen • Identify unsatisfactory specimens

MICROBIOLOGICAL DIAGNOSISLAB EXAM • • Direct exam – Microscopy –rapid presumptive diagnosis Saline wet preparation of stool Gram, s stain, Ziehl-Neelsen stain, Leishman, s stain, • Culture –amplification in number of pathogens, • Selective media –discrimination between pathogens & non-pathogens

MICROBIOLOGICAL DIAGNOSISLAB EXAM • Culture on solid media –isolated colonies for identification & susceptibility testing • Media for bacterial culture • Serology & antigen detection –rapid diagnosis, organisms difficult to culture

HAZARDS IN PATH LABS • • unsafe premises Naked flames Chemical hazards Glassware hazards Equipment hazards Explosions Microbial hazards

BIOHAZARDS IN PATH LABS • Ingestion – • Contaminted fingers, mouth pipettting, eating food in lab, • Inoculation – • Needlestick injuries , injury from broken contaminated glassware, open uncovered skin wound

BIOHAZARDS IN PATH LABS • • Inhalation – Infected airborne droplets Infection of general public – Escape of microorganisms during transport, improper disposal of infectious waste

Classificaton of infective microorganisms • Risk group 1 – • Low risk to lab worker & members of community eg. Food spoilage bacteria, yeasts, common moulds

Classificaton of infective microorganisms • Risk group 2 – • moderate risk to lab worker & limited risk to members of community, • Can cause serious human disease • Staphylococci, streptococci, enterobacteria, clostridia, vibrio, adenovirus, poliovirus, hepatitis viruses, toxoplasma, leishmania

Classificaton of infective microorganisms • Risk group 3 – • High risk to lab worker & low risk to members of community, • Can cause serious human disease • Brucella spp, Mycobacterium tuberculosis, S. typhi, francisella, arboviruses, LCM virus, rickettsiae, chlamydia, coccidioides, histoplasma, HIV

Classificaton of infective microorganisms • Risk group 4 – • High risk to lab worker & to members of community, • Can cause serious human disease & readily transmitted from one person to another • Viruses of haemorrhagic fevers, Marburg, Lassa, Ebola

SAFE LAB PRACTICES • • Safe working environment – Display safety signs & notices Keep lab clean Separate & dispose waste Decontamination procedures Disinfectants & their use in lab Sterilization Regulations for safe packaging & transport of specimens • Reporting of faults

SAFE LAB PRACTICES • • SAFE WORKING PRACTICESPersonal hygiene Protective clothing Preventing lab acquired infections Handling of spillage of a specimen Working tidily, use of racks, Use of protective gloves, goggles, face shield, dust mask,

DUTIES OF LAB SAFETY OFFICER • Monitor safety reg in lab • Staff taught to handle fire, equipment fault, specimen or chemical spillage • Test methods are safe • No mouth pipetting • Use of protective clothing in lab • No smoking, eating, drinking, applying cosmetics

DUTIES OF LAB SAFETY OFFICER • maintenance of first aid box, eye wash bottles, fire extinguishers • Cleanliness of lab, benches free of books & personal property • Maintenance of equipment • Observe safety regarding pts & visitors to lab are followed • Check structural defects in lab • Review & discuss safety reg with staff

UNIVERSAL PRECAUTIONS • Blood & certain body fluids ( amniotic fluid, CSF, pleural fluid, peritoneal fluid, pericardial fluid, semen, vaginal secretions, any fluid visibly contaminated with blood ) of all patients are potentially infective.

UNIVERSAL PRECAUTIONS • Hand washing before & after all patient contact • Use of gloves if soiling of hands with blood is likely • Gowns should be worn if soiling of skin or clothing is likely • Mask • Protective eyewear • Private room for patient if hygienic practices are poor

UNIVERSAL PRECAUTIONS • Proper disposal of contaminated needles/sharps in puncture resistant containers • No resheathing/recapping of used needles • Spills of blood – cleaned with 1: 10 dil of bleach • Barrier precautions ( masks, protective eyewear, gowns ) indicated, when splashes are expected to be generated.

LAB INFECTIONS - TYPES OF ACCIDENTS • • Splashes & sprays Needlesticks, sharp objects, Mouth pipetting Animal bite or scratch

MICROBIOLOGY • Five basic techniques in microbiology –five I, s • Inoculation, incubation, isolation, inspection, identification