VARICELLA ZOSTER (VZ) VIRUS, CHICKENPOX & SHINGLES GUIDANCE

Transcription

1 VARICELLA ZOSTER (VZ) VIRUS, CHICKENPOX & SHINGLES GUIDANCE Summary This guidance provides background information on varicella zoster (VZ), chickenpox and shingles and sets out the infection control measures needed to manage patients with either suspected or known infection. + Key Points The essential elements of this guideline are: Clinical features Routes of transmission Infection control measures Management of infected patients Guidance for staff if affected Date Ratified: 13 th December 2013 Page 1 of 8

2 Contents 1. Introduction Clinical Features Transmission Infectious Period Testing Infection Control Measures Standard Infection Control Precautions Isolation Hand Hygiene Personal Protective Equipment Relatives/Visitors Staff Contacts Immunocompromised Contacts Pregnant Contacts Maternity Unit/Neonatal Unit Notification References Publication Details... 6 Appendix 1. Management of paediatric patients following significant exposure to varicella zoster (chickenpox) or herpes zoster (shingles) Date Ratified: 13 th December 2013 Page 2 of 8

3 1. INTRODUCTION 1.1 Chickenpox (varicella) is a highly infectious disease caused by the varicella zoster (VZ) virus. The incubation period is between days. Chickenpox usually confers lifelong immunity, although the virus persists in a latent form in the sensory nerves. Reactivation of the latent varicella virus in later life results in shingles (Herpes zoster). It is not known what causes the virus to reactivate; reactivation can be spontaneous or follow a period of physical illness or stress. 1.2 Immunization against varicella is available. It is Trust policy to offer varicella vaccine to all non immune employees working in clinical areas (refer to the Screening and Immunisation Policy). 2. CLINICAL FEATURES 2.1 Chickenpox Characterised by a blister-like itchy rash, appears initially on the face, scalp and trunk, but can spread over the entire body. Other symptoms which may precede the rash by 48 hours include general malaise, fever and headache. 2.2 Shingles The virus causes severe pain and itching followed by the development of blister-like lesions, occurring at the site of the affected sensory nerve, typically causing a strip-like pattern on one side of the body. 3. TRANSMISSION 3.1 Chickenpox Chickenpox is transmitted through direct person to person contact, via airborne spread of respiratory droplet nucleii, and vesicle fluid or through contact with infected articles such as clothing and bedding. 3.2 Shingles Shingles is much less infectious than chickenpox although spread may occur from patients who have extensive lesions and susceptible contacts can develop chickenpox. Transmission can occur through direct contact with exudate from wet lesions or airborne via vesicle fluid in disseminated shingles. 4. INFECTIOUS PERIOD 4.1 Chickenpox The most infectious period is from one to two days before onset of the rash and continues for one week after onset or until all lesions are dry and have crusted. NB immunosuppressed patients may be infective for longer. Date Ratified: 13 th December 2013 Page 3 of 8

4 4.2 Shingles For one week following onset of eruption or until lesions are dry. NB period of infectivity may be slightly reduced by aciclovir. 5. TESTING 5.1 Adults suspected of having chickenpox require a viral swab taken from a wet vesicle. 5.2 In children, any lesions that look secondarily infected should also be swabbed for MC&S and necrotising fasciitis considered. Discuss antibiotic treatment with a microbiologist. 6. INFECTION CONTROL MEASURES 6.1 Patients with chickenpox or shingles must only be attended by staff known to be immune (refer to screening and immunisation policy). 7. STANDARD INFECTION CONTROL PRECAUTIONS 7.1 Standard infection control procedures must be used for all patients regardless of perceived or known infection risk factors (refer to standard infection control precautions policy). 8. ISOLATION 8.1 Admission of patients with chickenpox should be avoided where possible. In acute settings, patients with suspected or confirmed chickenpox must be isolated immediately in a single room. If symptoms develop during an inpatient stay, transfer to a single room should occur promptly. Isolation rooms used require en-suite facilities, preferably negative pressure, and doors must be kept closed. If capacity available, admission / transfer of adult patients to Torridge ward (refer to operational policy for infection control and Torridge ward). 8.2 Patients with shingles should be nursed in a single room during their infectious period. A single room with negative pressure ventilation is not required. 8.3 If isolation is inappropriate for the patient s mental health seek advice from the Infection Control Nurses. 9. HAND HYGIENE 9.1 In addition to routine hand hygiene at the point of care, hands should be washed with soap and water after removing personal protective equipment prior to leaving the isolation room. Once outside the isolation room repeat hand hygiene. 10. PERSONAL PROTECTIVE EQUIPMENT 10.1 In addition to Standard Infection Control Precautions, the use of gloves and aprons are also required for direct patient contact or cleaning. Date Ratified: 13 th December 2013 Page 4 of 8

5 11. RELATIVES / VISITORS 11.1 Non immune visitors should be advised and excluded from visiting during the infective period. 12. STAFF CONTACTS 12.1 Please refer to the Occupational Health Varicella Zoster Virus Policy. 13. IMMUNOCOMPROMISED CONTACTS 13.1 Following known or possible exposure, immunocompromised patients with no known history of chickenpox should have their immune status checked by serology and a microbiologist should be contacted. Varicella Zoster immunoglobulin (VZIG) should be given to susceptible contacts and is available from Microbiology Special groups of patients, especially bone marrow transplant patients, may not be immune, even if they have had previous chickenpox. For advice contact Microbiology. 14. PREGNANT CONTACTS 14.1 Following known or possible exposure pregnant patients and staff should have their immune status checked. If susceptibility is confirmed by antibody testing the women should be offered Varicella-Zoster Immunoglobulin (VZIG). This must be given within 10 days of contact. Due to the potential risks to the unborn child, pregnant staff should not care for infectious patients unless their immunity has been confirmed by antibody testing. If unsure, staff should check their immune status with Occupational Health. 15. MATERNITY UNIT/NEONATAL UNIT 15.1 Women with chickenpox must not be admitted to the maternity unit unless there is an overriding obstetric need. The immune status of mothers who have been exposed to a suspected or confirmed case of either chickenpox or shingles should be assessed. Pregnant contacts with a positive history of chickenpox do not require VZIG. Those with a negative history must be tested for VZ antibody before VZIG is given. The outcome in pregnant women is not adversely affected if administration is delayed up to 10 days after initial contact while a VZ antibody test is undertaken In addition to the infection control measures above, if a mother has or develops chickenpox whilst on the Maternity Unit the following measures are also required; I. Isolate from other mothers, babies, neonates and those known to be susceptible II. If mother develops chickenpox less than 7 days before delivery or up to 7 days after, her baby must be given VZIG Microbiology hold the stocks Date Ratified: 13 th December 2013 Page 5 of 8

6 III. VZIG is also indicated for babies of exposed susceptible mothers 16. NOTIFICATION 16.1 Healthcare staff must report, at the earliest opportunity, patients suspected or infected with varicella zoster virus (chickenpox or shingles), to the Infection Control Team (refer to the infection control policy). 17. REFERENCES Department of Health (2006) Immunisation against infectious disease (Green Book) edited by Salisbury D, Ramsay M & Noakes K. (Internet) available from; licyandguidance/dh_ Health Protection Agency (2009) General Information on Chickenpox (Varicella). (Internet 05/02/09) available from; ?p= Health Protection Agency (2008) Management of neonates exposure to vesicular (varicella/herpes Zoster). (Internet) available from; ?p= Guidelines on the management of, and exposure to, rash illness in pregnancy (including relevant antibody screening programmes in pregnancy). PHLS (2002). Internet available from; f 18. PUBLICATION DETAILS Author of Guideline Directorate/Department responsible for Guideline Contact details Judy Potter, Lead Nurse/Director of Infection Prevention & Control 2355/judith.potter2@nhs.net Version number 7 Replaces version number 6 Date written 1997 Approving body and date approved Review date June 2016 Expiry date December 2016 Date document becomes live 27 th March 2014 Infection Control Operational Group, 13 th December 2013 Date Ratified: 13 th December 2013 Page 6 of 8

7 Appendix: 1 Management of paediatric patients following significant exposure to varicella zoster (chickenpox) or herpes zoster (shingles) 1. Period of communicability Varicella zoster As long as 5 but usually 1 2 days before onset of rash, and continuing until all lesions are crusted. Herpes zoster Individuals may be infectious for one week after the appearance of vesiculopustular lesions. 2. Definition of a significant exposure Varicella zoster contact is defined as any patient or staff member who is nonimmune to the varicella-zoster virus and who has had contact with a case of chickenpox at anytime from 48 hours before the onset of the rash until all the lesions are crusted. Herpes zoster contact can be defined as any patient or staff member who is nonimmune to the varicella-zoster virus and who has had contact with a case of disseminated, exposed shingles from the day of the rash until crusting of the exposed rash. Patients should be considered immune if there is a good history of chicken pox or episode of zoster in the past or antibody test confirms specific antibodies or varicella immunisation complete. When deciding what constitutes an exposure the following aspects are relevant. 2.1 Type of VZ infection in the index case: The likelihood of infection in the index case must be assessed by a doctor and infectious chickenpox or shingles must be the likely diagnosis. 2.2 Closeness and duration of contact: Contact in the same room or within 10 metres on an open ward for 15 minutes or more Direct face to face contact for three minutes Contact with clothing and bedding soiled by discharge from the blisters Maternal neonatal transmission Continuous household Significant contacts that are believed to be non-immune are at risk of developing chicken pox and should be advised of this possibility. 3. Methods of control Isolation is the preferred option Paediatric patients with a history of recent contact as defined above should be isolated in a single cubicle on Bramble. Date Ratified: 13 th December 2013 Page 7 of 8

8 Neonates at risk of chickenpox who require neonatal unit care may be isolated on the neonatal unit only if it is unsafe to nurse them elsewhere in a single room. Babies who are exposed to chickenpox after discharge to the neonatal unit who require hospital admission must be admitted to Bramble Ward and NOT the NNU. If Bramble Ward is unable to isolate the patient due to ward pressures a risk assessment of patient groups will determine whether non-immune asymptomatic contacts can be placed with other children in a bay. The patients considered suitable to expose to a child who may be incubating chickenpox include: Those considered to be immune Those most likely to be discharged home within a short period The patients who should not be exposed to a child who may be incubating chickenpox are: Those who are immunocompromised Those likely to remain in hospital during the full incubation period Those who attend regular day case and out patient appointments Date Ratified: 13 th December 2013 Page 8 of 8