Monkey pox virus - Microbiological aspects - Comment
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Monkey pox virus - Microbiological aspects 1. MONKEY POX - the next pandemic ? DR. NILAKSHI GUPTA SENIOR RESIDENT LOK NAYAK HOSPITAL, NEW DELHI 2. HISTORY Monkeypox- Initial discovery in monkeys in a Danish laboratory in 1958. First human case- 9-year-old boy in the democratic republic of the Congo in 1970 3. Clade West african clade Congo basin clade Severity Less severe More severe Case fatality rate 3.6% 10.6% Transmissibility Less More CLADES OF MONKEYPOX VIRUS 4. VIROLOGY Enveloped double-stranded DNA virus Family: poxviridae Genus: orthopoxvirus . 5. EPIDEMIOLOGY Viral zoonosis Since 1970, human cases of monkeypox have been reported in 11 african countries The true burden of monkeypox is not known. 6. Monkeypox cases in non-endemic countries reported to WHO between 13 to 21 may 2022 7. MODE OF TRANSMISSION Virus enters body through broken skin, respiratory tract, or mucous membranes [eye, nose, mouth]. Direct contact close contact with lesions, body fluids, respiratory droplets Indirect contact contaminated materials such as bedding. Human to human Animal to human Bites Scratches Bush meat preparation 8. CLINICAL FEATURES Invasion period Lasts between 0–5 days Characterized by fever, intense headache, lymphadenopathy (swelling of the lymph nodes), back pain, myalgia (muscle aches) and intense asthenia (lack of energy). Lymphadenopathy is a distinctive feature of monkeypox compared to other diseases that may initially appear similar (chickenpox, measles, smallpox) Incubation period: 6 to 13 days but can range from 5 to 21 days. 9. Period of rash- within 1–3 days of appearance of fever. More on the face and extremities rather than on the trunk. It affects face (95%), and palms of the hands and soles of the feet (75%). Also affected are oral mucous membranes (70%), genitalia (30%), and conjunctivae & cornea (20%) The rash evolves sequentially from macules to papules vesicles pustules and crusts which dry up and fall off. The number of lesions varies from a few to several thousand. 10. Macules (lesions with a flat base) papules (slightly raised firm lesions) Vesicles (lesions filled with clear fluid) Pustules (lesions filled with yellowish fluid) scabs At the SAME STAGE of development over all affected areas of the body. Usually self-limiting Symptoms may last from 2-4 weeks. May be severe in some individuals, such as children, pregnant women or persons with immune suppression due to other health conditions. 11. LABORATORY DIAGNOSIS Optimal diagnostic samples: skin lesions – the roof or fluid from vesicles and pustules, and dry crusts. Where feasible, biopsy is an option. Lesion is swabbed vigorously, to ensure adequate viral DNA is collected. Both dry swabs and swabs placed in viral transport media (VTM) can be used. Two lesions of the same type should be collected in one single tube, preferably from different locations on the body and which differ in appearance. 12. All specimens being transported should have triple packaging, labelling and documentation. Specimens should be refrigerated or frozen within an hour of collection and transported to the laboratory as soon as possible. If transport exceeds 7 days, specimens should be stored at -20°c or lower. Longer term specimen storage (>60 days from collection) is at -70°C. 13. DIAGNOSIS Confirmatory test: Polymerase chain reaction (PCR) is the preferred laboratory test Nucleic acid amplification testing (NAAT), using real-time or conventional polymerase chain reaction (PCR), for detection of unique sequences of viral DNA. PCR can be used alone, or in combination with sequencing. PCR protocols for the detection of OPXV and more specifically MPXV-With distinction of Congo basin and west African clades. 14. Some protocols involve two steps, in which the first PCR reaction detects OPXV, but does not identify which species. This can then be followed by a second step, which can be PCR-based or utilize sequencing, to specifically detect MPXV. Disposal of waste: All waste that may contain MPXV should be decontaminated before disposal by autoclaving or chemical disinfection. 15. OTHER METHODS Electron microscopy: Electron microscopy can be used this method is not routinely used for the diagnosis of poxviruses. Viral culture: Virus isolation is not recommended as a routine diagnostic procedure. 16. Antigen and antibody detection methods do not provide monkeypox- specific confirmation due to serological cross-reactivity Not recommended for diagnosis 17. INFECTION CONTROL Isolation of patient Use of personal protective equipment Proper hand hygiene and cleaning procedures Household disinfection 18. ISOLATION OF PATIENT Persons with extensive lesions should be isolated in a separate room. Household members should limit contact with the infected person. Infected people should also avoid contact with animals, including pets. 19. USE OF PERSONAL PROTECTIVE EQUIPMENT Persons with monkeypox should wear a surgical mask, Disposable gloves should be worn for direct contact with lesions and disposed of after use. Skin lesions should be covered to the best extent possible (Long sleeves, long pants) to minimize risk of contact with others. Contain and dispose of contaminated waste (such as dressings and bandages) should be done according to biomedical waste disposal. 20. PROPER HAND HYGIENE AND CLEANING PROCEDURES Hand hygiene- Hand washing with soap and water or use of an alcohol-based hand rub should be done. Hand hygiene is to be performed after touching lesion material, clothing, linens, or environmental surfaces. 21. HOUSEHOLD DISINFECTION Laundry: To be washed separately to avoid direct contact with contaminated material. Soiled dishes and utensils should be with warm water and soap. Contaminated surfaces should be cleaned and disinfected. Standard household cleaning/disinfectants may be used. 22. INFECTION CONTROL PRECAUTIONS By health workers- To implement standard, contact and droplet precautions Recommended personal protective equipment (PPE) includes gloves, gown, medical mask and eye protection – goggles or face shield Aerosol generating procedures should be done by taking proper precautions. Continue until all lesions have resolved and a fresh layer of skin has formed. 23. VACCINATION Data from Africa suggests that smallpox vaccine is at least 85% effective in preventing monkeypox. JynneosTm (also known as imvamune or imvanex), has been licensed in the united states to prevent monkeypox and smallpox. Acam2000, which contains a live vaccinia virus, is licensed for immunization in people who are at least 18 years old and at high risk for smallpox infection. It can be used in people exposed to monkeypox if used under an expanded access investigational new drug protocol. 24. TREATMENT An antiviral agent known as TECOVIRIMAT[ST-246] developed for smallpox was licensed by the European medical association (EMA) for monkeypox in 2022. Data is not available on the effectiveness of cidofovir and brincidofovir in treating human cases of monkeypox. However, both have proven activity against poxviruses in in vitro and animal studies. Currently, there is no proven, safe treatment for monkeypox virus infection. For purposes of controlling a monkeypox outbreak, smallpox vaccine, antivirals, and vaccinia immune globulin (vig) can be used 25. RECOMMENDED PUBLIC HEALTH ACTION- NCDC,MOHFW, MAY 2022 1. Health care facilities to keep heightened suspicion in people who; a. Present with otherwise unexplained rash and b. Who have travelled in the last 21 days to a country that has recently confirmed or suspected cases of monkeypox or c. Report contact with a person or people with confirmed or suspected monkeypox. 26. 2. All suspected cases to be isolated at designated healthcare facilities untill all lesions have resolved and a fresh layer of skin has formed OR until the treating physician decides to end isolation. 3. All such patients to be reported to the district surveillance officer of IDSP. 4. All infection control practices to be followed while treating such patients. 5. Laboratory samples consisting of fluid from vesicle ,blood, sputum etc to be sent to NIV pune for testing in case of suspicion 6. In case a positive case is detected, contact tracing has to be initiated immediately to identify the contacts of the patient in the last 21 days. 27. REFERENCES 1. Interim advisory for IDSP ssus in view of monkeypox cases reported from few countries. 2. https://www.who.int/news-room/fact-sheets/detail/monkeypox 3. www.cdc.gov/poxvirus/monkeypox. 28. WE THINK WE ARE DONE WITH THE PANDEMIC, BUT THE PANDEMIC IS NOT DONE WITH US. THANK YOU |
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| Posted by : peter88 | Post date : 2022-08-03 17:21 | ||
| Category : Health & Medicine | Views : 545 | ||
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