Infection Control & Environmental Cleaning Lecture 7 PDF

49 ‫المحارضة‬ ‫المحارضة‬ ‫حضور‬ ‫حضور‬ ‫عن عن‬ ‫يغين‬...

49 ‫المحارضة‬ ‫المحارضة‬ ‫حضور‬ ‫حضور‬ ‫عن عن‬ ‫يغين‬ ‫يغين‬ ‫العمل ال‬ ‫العمل ال‬ ‫هذاهذا‬ Infection Control ‫هذا العمل ال يغين عن حضور المحارضة‬ 07 Environmental Cleaning ‫ جـ‬### :‫سعر الوجــــه‬ ‫ جـ‬### :‫سعر الوجهني‬ Environmental Cleaning & Disinfectant 3 factors (chemicals, equipment, ‫ وكانوا‬disinfection ‫ و‬cleaning ‫ عرفنا المحاضررررر اللي فاتت العوامل اللي بتأثر على‬ techniques) ) equipment, techniques( factors ‫ هنكمل النهارد باقي الر‬chemicals ‫ وهو‬factor ‫ وخدنا اول‬ 2. Cleaning equipment  In general, all cleaning equipment used in healthcare facilities should be fit for purpose, cleaned and stored dry between use, well maintained and used appropriately.  Equipment which generates and disperses dust such as feather dusters should NOT be used within the healthcare facility.  The use of spray bottles or equipment that might generate aerosols during usage should be avoided??  Chemicals in aerosols may cause irritation to eyes and mucous membranes.  Containers that dispense liquid such as ‘squeeze bottles’ can be used to apply detergent/disinfectants directly to surfaces or to cleaning cloths with minimal aerosol generation. ‫ و هي القما شه اللي بنضف‬cloths ‫ او جردل الم سح او‬mop ‫ الحاجات اللي ب ستخدمها زي الررررر‬cleaning equipment ‫عندي‬  ‫ او عايز‬mop ‫بيها وطبعا وانا بختار األدا الزم تكون منا سبه للحاجه اللي عايز ان ضفها زي مثال هم سح االرض فه ستخدم الرررررر‬ cloths ‫ فهستخدم‬tray ‫امسح‬ ‫جردل المسح بعد ما بخلص تنضيف واغسله واشيله ممكن يتجمع فيه تراب من الجو فالحل اني احطه مقلوب عشان امنع د‬  ‫ بس بتخليه‬surface ‫الريشرره بتاعت تنضرريف التراب مينفعد ابدا اسررتخدمها في المسررتشررفيات النها بتشرريل التراب من الرررررر‬  ‫ ف الجو‬suspended ‫ فبتخليها برضررررو‬chemicals ‫ مينفعد اسررررتخدمها النها بتحتوي على حاجات‬aerosols ‫ او اي حاجه تعمل‬spray bottles ‫اي‬  ‫ للمر ضى الموجودين في الم ست شفى‬irritation to eyes and mucous membranes ‫ في الجو ود ممكن يعمل‬suspended ‫طب استخدم ايه؟‬, ‫ دي بتطلع الحاجه اللي انا عايز احطها على طول على السطح من غير ما يطلع ف الجو‬squeeze bottles ‫استخدم‬  Cleaning cloths  are the main materials that are used for cleaning of surfaces in healthcare facilities.  Care needs to be taken to ensure that cleaning cloths are suitable for purpose, that there is sufficient quantity for staff to undertake their duties effectively and that they are used appropriately to prevent cross contamination of surfaces.  If a healthcare facility is choosing to use reusable cleaning cloths, a system should be developed that ensures that a clean cloth(s) is used for each patient area (single room, shared room).  Failure to do so could compromise the effectiveness of the cleaning process.  The cloths should be laundered after each day’s use and in accordance with the Standard Laundry practice. However, facilities may also consider using disposable cloths instead, especially for wet areas where the contamination may be higher. ‫ اكتر من العياد‬cloths ‫ هتحتاج‬icu ‫ يعني مثال المستشفى و‬cloths ‫ الزم اهتم بالكميه بتاعت الر‬ ‫ يعني استخدام مر واحد وتترمي‬disposable ‫ لو فيه انفكشن بستخدم‬ ‫وع شان ب ستخدمها اكتر من‬, ‫ وامنع االنفك شن‬sterilization ‫ يعني ممكن ا ستخدمها اكتر من مر لو ينفع اعملها‬reusable ‫ او‬ ‫مينفعد‬, standard laundry practice ‫ معينه بسررميها‬precautions ‫ تحت‬laundry ‫مر الزم يكون فيه مغسررله وبنقلها للرررررر‬.‫دي مع الماليات وغطيان المخدات في نفس الوقت كل حاجه بيبقى ليها وقت منفصل‬cloths ‫لغسل الر‬  Detergent and/or disinfectant-impregnated wipes are useful for ‫ بيكون فيها‬wipes ‫ بستخدم‬ decontaminating small items of patient care equipment or high touch Detergent and/or disinfectant surfaces, particularly in clinical outpatient areas, e.g. radiology. radiology ‫مع الحاجات الصغير زي‬  They should NOT be used for cleaning large surface areas since they ‫لكن مد بستخدمها مع الحاجات‬ do not generally contain enough product to cover large areas, and ‫الكبير النها هتحتاج كميات كبير‬ many wipes would be required for effective decontamination..‫ود هيكلف كتير‬ 1  Infection Control Environmental Cleaning 07 Cleaning equipment  (including containers, mop heads etc.) should be inspected regularly and mop heads ‫ و‬containers ‫ الر‬ changed when required. ‫بغسلهم بعد االستخدام وزي‬  The following basic principles should be followed: ‫ماقلنا الجردل بنحطه مقلوب‬ ‫عشان ميجمعد تراب واتابعه‬  equipment such as containers should be washed with detergent and ‫باستمرار لو فيه خدوش‬ disinfectant AFTER each use and stored upside down and allowed to dry ‫مينفعد استخدمه النها‬ between use. They should be also inspected for cracks and replaced dust ‫ او‬m.o ‫بتحجز فيها‬ accordingly. ‫بيبقى صعب تنضيفها‬  Mop heads and cleaning cloths should be changed and laundered daily or after use (if used less frequently than daily).  equipment such as cloths and mop heads which are used to clean blood or body fluid spills or used in isolation rooms should either be disposable and discarded after use, or if re-usable, changed immediately after use and placed in a plastic bag for transport to the laundry. 3. Cleaning techniques  Incorrect or inappropriate cleaning techniques may spread micro-organisms around rather than removing them from the surface.  The following points should form the basis of all standard operating procedures regarding cleaning in healthcare facilities:  The flow of cleaning should be from areas which are considered relatively clean to dirty.  This means that areas/elements which are low touch or lightly soiled should be cleaned before areas/elements which are considered high touch or heavily soiled.  For example: when cleaning a bathroom, the toilet should be cleaned last as it is likely to be the most contaminated element in that area dirty ‫ اللي‬clean ‫ بيكون من المكان‬cleaning ‫ اتجا الر‬  The flow of cleaning should generally be from high to low reach ‫ بيكون من‬cleaning ‫ كمان اتجا الررر‬ surfaces. low ‫ اللي‬highly reach ‫االماكن الررر‬  For example: ‫ يعني بنضررررف من فوح لتحت‬reach  when dusting horizontal surfaces in a patient room, high areas ‫(يعني مثال لو قدامي حاجه بنضرررفها‬ such as those above shoulder height should be done first followed ‫ون ضفت الجزء اللي تحت االول ممكن‬ by all other elements. ‫ من الجزء الي فوح اللي لسررره‬dust  Dusting technique should not disperse the dust (i.e. use damp )‫متنضفد تقع عليه‬ cloths).  When using cloths and bucket/solution system to clean: avoid ‫ وحطيتها في‬cloths ‫ لو جبت الر‬ ‘double-dipping’ used cloths into the bucket containing clean, unused ‫ بتاعي وكله تما‬container ‫الر‬ cloths. ‫وهبدا انضف مينفعد اعمل‬  Doing this can contaminate the remaining clean cloths which are in ‫اني‬ ‫ بمعنى‬dipping double container ‫ من الر‬cloth ‫خدت‬ the solution and result in spreading micro-organisms to surfaces that ‫بتاعي ونضفت مينفعد ارجعها‬ are wiped thereafter. ‫تاني عشان هتلوث باقي‬  More cloths may be required to clean "high-touch surfaces" compared cloths ‫الر‬ to the same surface area of "low-touch surfaces".  Upon completion, the whole area should be visually checked to ensure check ‫ بعد ما اخلص الزم اعمل‬ the area is thoroughly cleaned and that elements have not been missed. ‫عشان اتاكد اني نضفت كل‬ ‫االماكن‬ 2  Infection Control Environmental Cleaning 07 Cleaning schedule  As micro-organisms are invisible to the naked eye, a surface can appear surfaces ‫ الزم انضررررف كل‬ visibly clean while covered with many micro-organisms that can spread to ‫بررانتمررام الن ممكن اكون‬ other patients and potentially cause infection. ‫شررايفه المكان نضرريف بس‬  All surfaces should therefore be cleaned regularly even if the element appears ‫ مد بشرررروفها‬m.o ‫عليها‬ to be visibly clean. However, there are several factors that need to be taken ‫حتى لو المكرران فرراضرررري‬ into consideration in determining the cleaning schedule (i.e. cleaning ‫مفيد مرضررى الزم انضررف‬ frequency and method) and they include the risk classification of functional ‫برضو‬ areas and the risk associated with the individual element. Functional areas  A functional area refers to an area within the facility in which ‫ هو اي مكان جوا‬functional area ‫ ال ر‬ cleaning occurs, for example, intensive care unit (ICU), operating ‫ محتاج تنضرررريف‬healthcare facility rooms, general ward, cafeteria etc. ‫مد بس غرف العمليررات او العنررايرره‬ ‫المركز والع نابر وال كافيتيريا ال ع ندي‬  Where bathrooms, corridors, storerooms, meeting rooms, offices, ‫ك مان زي (الم كا تب والممرات وغرف‬ and lounge rooms etc. provide direct open access into the functional ‫ وباقي‬manager room ‫االسررتراحه و‬ area, these areas must receive the same level of cleaning as the )‫االمثله فوح‬ functional area itself. #‫الدكتوره اكدت على الجزء ده‬# How was the risk classification of functional areas determined?  Each functional area is given a score based on:  The probability of contamination  Vulnerability of the patients to  Potential for exposure infection  A total score for the functional area is determined and the risk classification could be "high", "moderate" or "low" risk.  In general, the higher the risk classification of a functional area, the more frequent cleaning needs to occur.  For example, an ICU (high risk) will be cleaned more frequently than a general ward (moderate risk) or office area (low risk). ‫ ودا بتعتمد على مدى احتماليت االصابه بالعدوى فى‬low, high, moderate risk ‫ اللى‬functional area ‫ بتاع ال‬risk ‫ بقسم الررر‬ ‫األماكن دى يعنى مثال‬ contamination ‫ النها بتكون معرضه للر‬risk ‫ األماكن او االشياء إللى بيروح إليها المريض أكتر بيكون األكثر‬ ‫ ودا معنا اختالف الحاله الصحيه للر‬vulnerability of the patient to contamination ‫ هو ال‬risk ‫ تانى عامل بتحدد الررر‬ general wards ‫ بيكون و معرضين إلصابت أكتر من المرضى فى‬ICU ‫ يعنى مثال المرضى اللى فى‬patients.‫ مقابض األبواب‬، ‫ تالت عامل بيأثر األماكن التى ييتعامل معها المريض زى مفاتيح اإلضاءة‬ Risk classification of the functional area within the health care facility: Very High Risk  Outbreak situation  Outbreak situation  Intensive care unit  High dependency unit  Operating rooms  recovery, burns unit  Renal & haemodialysis units High Risk  Emergency  Transplant,  Invasive procedure rooms department haematology  oncology units (including neutropenic patients)  Labour & birthing unit  Autopsy/morgue  Equipment reprocessing & sterilisation area  General wards Moderate Risk  Treatment/procedure rooms: e.g. podiatry,  Pharmacy-admixture room & optical, general dental general purpose area  High use public areas e.g. outpatients  Laundry (soiled)  Laundry (clean linen)  Long term care areas  Non-invasive procedure rooms  Plant room, engineering, records Storage Low Risk  Low use public areas (e.g.  Sterile supply areas administration, meeting rooms ( 3  Infection Control Environmental Cleaning 07 high risk, low risk, ‫ اللى‬functional areas ‫ ويقسررم الررررررر‬،‫ أكتر‬frequency of cleaning ‫ أعلى هحتاج‬risk ‫ كلما كان الررررررر‬.) ‫ زى ما واضح فى الجدول ( األمثلة مهمة‬moderate risk ‫ بدخل منه‬inlet ‫ بيكون له‬cleaning ‫ إللى بي ستخدم فى الرررررر‬cloth ‫ أو المكان إللى بتتغ سل فيه الرررررر‬laundry ‫ ناخد بالنا ان‬ low ‫ فبيكون‬cleaned cloth ‫ ودا بيكون فيه الررر‬outlet ‫ وبيكون له‬، moderate risk functional area ‫ ودا بيمثل‬dirty cloth ‫الررر‬ risk functional area  Note: in the event that there is an outbreak within any functional area, the risk classification is temporarily upgraded to “very high risk” irrespective of the usual score of the functional area.  This risk status is maintained until the outbreaknhas been resolved and downgraded. ‫ زى ايام الكورونا كد بتزيد كمان‬outbreaks ‫لكن فى الرررررر‬، ‫ زى ما و ضحنا فوح‬functional areas ‫ فى الو ضع الطبيعى بق سم‬.‫ ودى بتكون اماكن العزل واحتمال اإلصابت فيها بيكون كبير وخطير‬very high risk functional area‫الر‬ Elements:  An element refers to an item such as a surface, article, furniture to be cleaned.  For example: patient beds, lockers, blood pressure cuffs, walls, toilets, beds.  Cleaning frequency for each element is based upon the notion that all surfaces can be divided into two groups:  Those with minimal hand-contact (e.g. floors, walls, ceilings)  Those with frequent hand-contact ("high-touch surfaces") such as light switches.  The high touch surfaces should be cleaned more frequently than surfaces with minimal hand contact.  During an outbreak situation, the cleaning frequency will need to be increased. frequency of hand ‫ وبقسمه على حسب الر‬cleaning ‫ دا يعبر عن اى حاجه فى المستشفي محتاج أعملها‬element ‫مصطلح الر‬ : ‫ الي‬contact floor, walls, ceilings ‫ زى الر‬contamination ‫ ودى األماكن األقل عرضه للر‬minimal hand-contact.1 ‫ مقابض األبواب‬، ‫ متكرر زى مفاتيح اإلضرراءة‬hand contact ‫ ودى األماكن إللى دايما بيكون فيها‬frequent hand-contact.2.‫ لالماكن دى هيزيد‬frequent of cleaning ‫وبالتالى الر‬  Cleaning method for each element is based on the notion that some elements may be more contaminated than others (both in number and type of micro-organisms).  For example, all elements within wet areas (i.e. toilets, showers) must always be cleaned with detergent and disinfectant whereas elements such as patient bed rails and lockers need only be cleaned routinely with detergent. frequent cleaning ‫ فيها بسرعه وبالتالى بيحتاج‬M.Os ‫ بيكون نمو الر‬toilets & showers ‫ زى الر‬wetted ‫ األماكن الر‬ The different types of cleaning schedules:  that healthcare facilities are required to undertake include: :‫ أنواع‬٤ ‫ ينقسم إلى‬cleaning schedule ‫ الر‬ a. Standard Clean: Is The Minimum  Scheduled cleaning that is required to be conducted on an ongoing ‫ بسررميه‬standard cleaning ‫ الرررررر‬ basis irrespective of the perceived cleanliness of the element (for minimal schedule cleaning example, even if the floor in a ward appears visibly clean, it still is ‫ودا أسرراسرري الزم يتم فى كل الر‬ required to be cleaned daily in high and moderate risk functional ‫ حتى لو كررانررت‬functional areas areas)..‫فاضيه مفيهاش مرضى‬ b. Transmission-based clean: There are two  Different types of cleaning that are required to be conducted when there are patients on transmission- based precautions.  For example, a confirmed or suspected case of infection or colonisation with a multidrug-resistant organism, infectious respiratory pathogen, infectious gastroenteritis or Clostridioides difficile. respiratory ‫ زى مثال لو فيه‬، infection ‫ ودا بيختلف على حسب نوع الر‬transmission-based ‫ هو الر‬cleaning ‫ تانى نوع من الر‬ ‫ مختلف فى‬transmission based cleaning ‫ هعمل‬Clostridiem difficile ‫ ب سبب الرررررر‬gastroenteritis ‫ او ح صل‬infection :‫كليهما عشان أقلل انتشار العدوى وبيتقسم لنوعين‬ 4  Infection Control Environmental Cleaning 07  This clean applies when there is a single or several un-related case(s) in the functional area.  In general, the cleaning frequency remains the same as a standard clean; however, the cleaning method is intensified to detergent anddisinfectant for Single case(s): most elements in the localised area the case occupies, i.e., isolation room. ) single case ( ‫ عشان عندى حالت واحد مصابه بالعدوى‬cleaning precautions ‫ يعنى بزود الررر‬ ‫وفى‬، ) unrelated multiple cases ( ‫ مختل فه‬infections ‫أو عدة حاالت بس كلهم ع ندهم‬ transmission-based ‫الحاله دى لو لزم األمر اعزل كل مريض فى غرفه لواحد وهيزود فيها الررر‬ precautions is when there is an occurrence of more cases of the same infection than expected in a given area. In general, the cleaning frequency and method are intensified for the whole functional area. Outbreak clean: ‫ فبجمعهم مع بعض فى‬infection ‫ ع ندهم نفس الررررررررر‬multible cases ‫ ودا بيكون لو ع ندى‬ ‫ ( مد الزم اعزلهم عن بعض ألنهم ع ندهم‬precautions ‫ وا حدة وازود لهم‬functional area ) infection ‫نفس الر‬ c. Discharge clean:  this requires cleaning of specified elements within the ‫ دا بيتم اول ما المريض ي سيب المكان إللى‬ immediate patient care area and is required to be conducted after death or ‫كان فيه مباشررر سررواء حصررل‬ a patient vacates (i.e., is discharged, transferred or deceased) ، ‫ أو حتى لو انتقل لمكان تانى‬recovery and before the next patient enters the area..‫الزم المكان إللى كان فيه يتنضف مباشرة‬ d. Spot and spill clean:  to be conducted whenever elements appear visibly soiled or body fluid ‫ ودا ب ي تم اول مررا اال حا اى‬ when there is a spillage of body fluid (blood, vomit, urine, vomiting, blood, urine, ‫ل ل مر يض زى‬ faeces etc.)..‫ الزم تتنمف علطول باستمرار‬faeces ، case ‫ وبيكون على حسب كل‬cases ‫ ) مد بيكونوا فى كل الررررر‬discharge & spot and spill out( cleaning ‫ أخر نوعين من‬.‫ ألنه بيكون على حسب نوع العدوى المنتشرة‬specific ‫ أكتر نوع‬transmission ‫ والر‬، ‫ اساسى الزم يتم‬standard ‫ولكن الر‬ Sterilization and disinfection:  It is the destruction of ALL micro-organisms including bacterial spores.  Sterilization can be achieved by either:  Physical (heat sterilization)  Chemical methods (ethylene oxide sterilization).  Sterilization is necessary for medical devices penetrating sterile body sites, as well as all parenteral fluids and medications.  Cleaning to remove visible soiling in reusable equipment should precede sterilization. inanimate objects ‫ بيتم للرر‬، spores ‫ ويقدر كمان يقتل‬killing of 100% of M.Os (zero M.O ) ‫ معنا‬sterilization ‫ التعقيم اوالرر‬ physical or chemical methods ‫ وبيتم باستخدام‬.‫مينفعد بتعمل للكائنات الحيه‬ Disinfection:  It is a process by which vegetative i.e. growing forms of pathogenic organisms are killed.  The most commonly used disinfectants are sodium hypochlorite and 70% alchol. ‫ سررررواء باسررررتخدام‬spores‫ ومد بقدر اتغلب على ال‬vegetative cells ‫ يقتل ال‬disinfection ‫ال‬ sodium hypochlorite ‫ الكحول أو‬%٧٠ 5  Infection Control Environmental Cleaning 07 Investigation of an outbreak ‫ ووالمرحلت اللى بعد‬outbreak ‫ (مسرررتوطن) وبعدين وصرررل للحالت اللى بعدها اللى هى الرررررررر‬endemic ‫الكوفيد فى االول كان‬  epidemic ‫ هى انه يبقا‬outbreak ‫الر‬ Pandemic ‫ولما مقدرناش نسيطر عليه بقا وباء يقا‬  ENDEMIC EPIDEMIC PANDEMIC  Constant presence of a disease  Sudden increase in the number  An epidemic that has spread within a particular region or of cases of a disease above what over several countries or community without importation is normally expected in that continents, usually affecting from outside population/area a large number of people  Eg: Malaria, Schistosomiass  Eg: SARS, MERS  Eg: Plague, COVID-19 Identification of an "outbreak"  The occurrence of two or more similar cases relating to place and time is identified as a cluster or an outbreak.  It needs investigation to discover the route of transmission of infection, and possible sources of infection in order to apply measures to prevent further spread.  If the cases occur in steadily increasing numbers and are separated by an interval approximating the incubation period, the spread of the disease is probably due to person to person spread.  On the other hand, if a large number of cases occur following a shared exposure e.g. an operation, it is termed a common source outbreak, implying a common source for the occurrence of the disease. 6  Infection Control Environmental Cleaning 07 ‫ هو لما يكون عندي حالتين او اكتر عندهم نفس العدوى فى نفس المكان والزمن وبسمي الحاالت‬outbreak ‫ باختصار تعريف الررررر‬ cluster ‫دى‬ Steps to be taken to investigate an outbreak Step -1  Recognition of the outbreak  Is there an increase in the number of cases of a particular infection or a rise in the prevalence of an organism? Such findings indicate a possible outbreak.  Preliminary investigation  It must begin by developing a case definition, identifying the site, pathogen and effected population.  Determination of the magnitude of the problem and if immediate control measures are required.  If so, general control measures such as isolation of infected cases; strict hand washing should be immediately applied.  Verification of the diagnosis  Each case should be reviewed to verify the diagnosis.  Confirmation that an outbreak exists  by comparing the present rate of occurrence with the endemic rate should be made. ‫ زي زيادة اعداد الناس المصابت‬outbreak ‫الزم اتعرف على الحاجات اللىى ممكن تكون بدايت للر‬.1 ‫بحدد نوع العدوى ووالناس المصابت بيها‬.2 ‫ بتاع االنتشار‬rate ‫بشوف حجم المشكلت عشان االكشن اللي هاخد يكون مناسب مع الر‬.3 ‫لو االنتشار سريع ف هبدأ فى العزل عشان العدوى متتنقلد اكتر‬.4 ‫باخد عينات من المرضي واحللها عشان اقدر اوصل للسبب بشكل دقيق اكتر‬.5 Step -2  The appropriate departments and personnel and the hospital administration should be notified and involved. ‫ بعلن بقا فى المكان اللى انا فيه كل االقسام عشان نشوف هنعمل ايه وبنبلغ الحكومه طبعا‬ Step -3  Additional cases  must be searched for by examining the clinical and microbiological records.  Line listings  for every case, patient details, place and time of occurrence and infection details should be developed.  An epidemic curve  based on place and time of occurrence should be developed, the data analysed, the common features of the cases e.g. age, sex, exposure to various risk factors, underlying disease etc. should be identified.  A hypothesis  based on literature search and the features common to the cases; should be formulated to arrive at a hypothesis about suspected causes of the outbreak.  Microbiological investigations  depending upon the suspected epidemiology of the causative organism should be carried out. This will include (a) Microbial culture of cases, carriers and environment (b) Epidemiological typing of the isolates to identify clonal relatedness epidemic curve ‫ بشوف الريبورتات والتفاصيل بتاع المرضي عشان اعمل‬.1 ‫ وفقا للنتائج اللي طلعتلى هبدأ ادى اقتراحات للعالج وبرتوكوالت العالج اللي همشي عليها‬.2 M.O ‫ عشان اعرف الر‬microbial investigation ‫ بعمل‬.3 7  Infection Control Environmental Cleaning 07 Step - 4  Testing the hypothesis  by reviewing additional cases in a case control study, cohort study, microbiological study.  Specific control measures  should be implemented as soon as the cause of outbreak is identified.  Monitoring for further cases  A report  should be prepared for presentation to the ICC, departments involved in the outbreak, administration. ‫ بجرب بقا واطبق طرح العالج‬.1 m.o ‫ اللى هو باخد ادويت مخصصه للر‬specific control measure ‫ بعمل‬.2 epidemic ‫ متتحولد لر‬out break ‫ وبفضل اتابع بقا عشان الر‬.3 Immediate control measures  Control measures should be initiated during the process of investigation.  An intensive review of infection control measures should be made and general control measures initiated at once.  General measures include:  Strict hand washing;  Intensification of environmental cleaning and hygiene;  Strengthening of disinfection and sterilization. Epidemic curve  This is constructed to study the epidemic pattern of the disease.  An epidemic curve is a graph (histogram) in which the cases of disease that occurred during the outbreak are plotted according to time of onset of HAI of the cases.  The epidemic curve is constructed to help determine whether the source of infection is common & continuing, & identify the probable time of exposure of the cases to the source of infection & probable incubation period. 8