Giời leo (herpes zoster)

Bệnh lao là gì?

Herpes zoster (shingles) is caused by a reactivation of the varicella zoster virus (VZV), the same virus that causes thủy đậu (chickenpox) disease. After a person recovers from varicella, the virus stays dormant (inactive) within the dorsal root ganglia of the spinal nerves but can later be reactivated, presenting as zoster. Most people in Australia, especially those over 50 years of age, will have been exposed to varicella (chickenpox) virus in their childhood or adolescence. 

Triệu chứng cần nhận biết

Zoster is a painful, vesicular (blistering) rash. It usually presents on one side of the face or body, typically appearing in a dermatomal distribution (an area of skin supplied by a spinal nerve). Prior to the emergence of the rash, there is often pain, itching or tingling in the area where the rash will develop. This can happen anywhere from 1 to 5 days before the rash appears. Other symptoms of zoster can include fever, headache, chills and malaise (generally feeling unwell). The vesicles (blisters) typically scab over 7 to 10 days after onset and resolve completely within 2 to 4 weeks. 

Post-herpetic neuralgia (PHN) is the most common complication of zoster and is more likely to occur in older people (> 70 years) than younger people. PHN is a chronic neuropathic (nerve) pain which can affect 1 in 4 cases of zoster diagnosed in those aged > 80 years. It can persist for months or up to several years. Given that pain control for PHN can be difficult to manage, it can have a significant impact on quality of life. 

Other complications of zoster include skin pigmentation and scarring, secondary bacterial infections, and herpes zoster opthalmicus (eye involvement with differing degrees of symptoms including conjunctivitis, ocular-cranial nerve palsies, loss of vision and debilitating pain).

Bệnh lây truyền qua đường nào

Zoster cannot be passed from one person to another. It is the reactivation of an individual’s previous VZV infection (chickenpox). 

Exposure to the fluid-filled vesicles of a zoster rash can result in a VZV infection (as varicella disease) in a seronegative person (a person with no immunity to VZV). Zoster is less contagious than varicella. The risk of a person with zoster spreading the virus is low if the rash is covered. 

Dịch tễ học

Zoster can only develop in people who have previously been infected with VZV. It more commonly presents in adults aged > 50 years, those who are immunocompromised and those who were diagnosed with a varicella infection at < 12 months. Zoster episodes, including post herpetic neuralgia (PHN)requiring primary care presentation and /or nhập viện tend to impact Aboriginal and Torres Strait Islander people at an earlier age than other non-Indigenous Australians.

The lifetime risk of a reactivation of the VZV virus causing zoster is 20 to 30%. Zoster affects half of all people who live to 80 years. Zoster can present more than once. Repeated presentations occur in 6–8% of immunocompetent people whereas immunocompromised people experience higher rates of repeated presentations.

Phòng ngừa

The only way to reduce the risk of developing zoster is through vaccination, which helps suppress the VZV virus. There are currently 2 vaccines available in Australia:  

  • Shingrix – an adjuvanted recombinant varicella zoster virus glycoprotein E (gE) subunit (non-live) vaccine  
  • Zostavax – a live-attenuated vaccine.  

On 1 November 2023, Shingrix became funded on the National Immunisation Program (NIP) for the following groups: 

  • First Nations Australians aged ≥ 50 years 
  • all adults from ≥ 65 years 
  • immunocompromised adults from ≥ 18 years with certain medical conditions, including: 
    • history of haematopoietic stem cell transplant  
    • ghép tạng đặc  
    • blood cancer  
    • advanced or untreated HIV.  

In addition, immunocompetent, non-Indigenous adults aged 50 to 64 years who are household contacts of a person who is immunocompromised are recommended (but not funded) to be vaccinated. 

Immunocompetent, non-Indigenous adults aged 50 to 64 years who are not eligible to receive funded vaccines, and wish to be protected, can purchase a course of Shingrix.  

Primary course  

2 doses of Shingrix are required for adequate protection. 
Doses should be given 2 to 6 months apart for immunocompetent people or 1 to 2 months apart for those with immunocompromise. 
Shingrix can be co-administered with other vaccines including phế cầu khuẩn, cúm Và COVID-19 vắc-xin.  

tên lửa đẩy

There is no recommendation for boosters in people who have already completed a 2-dose course of Shingrix.  
People who have previously received Zostavax can receive Shingrix to increase their protection against zoster. There must be a minimum of 12 months between Zostavax and Shingrix. See commonly asked questions below for more detail.   

Phản ứng phụ 

Common side effects after Shingrix vaccination include phản ứng tại chỗ tiêm, fatigue, myalgia (muscle pain), headaches and fever which can last 1 to 3 days. These side effects are temporary and are much less severe than those following zoster diagnosis/zoster complications.  

An estimated additional 3 to 6 cases of Guillain–Barré syndrome (GBS) per million doses of Shingrix administered have been estimated to occur following Shingrix administration, with the risk–benefit profile supporting vaccination. 

Chống chỉ định và các biện pháp phòng ngừa

Zoster vaccines are không interchangeable with varicella vaccines as they are very different. Zoster vaccines are much more potent than varicella vaccines and are not recommended for use in children.  

Shingrix must không be administered for the treatment of varicella, acute shingles disease or PHN. 

Zostavax is a live-attenuated vaccine and is therefore contraindicated in immunocompromised individuals. 

Câu hỏi thường gặp

  • Should people with a clinical history of zoster be vaccinated?

    Yes. People can experience zoster more than once in a lifetime. Approximately 6 to 8% of immunocompetent people will have a repeat episode of zoster within 8 years of their first diagnosis. Further episodes are even more common for individuals with immune compromise. 

    Immunocompetent individuals should wait at least 12 months following a zoster diagnosis before being vaccinated. In the first 12 months after infection, the risk of a further episode is low. 

    Immunocompromised individuals are at an increased risk of further episode of zoster compared with immune competent people. It is recommended that they receive a 2-dose course of Shingrix a minimum of 3 months after acute illness. 

  • Should people who have previously received Zostavax receive Shingrix?

    There is some evidence that immunity can wane 5 years after a single Zostavax dose. In clinical studies, Shingrix in a 2-dose schedule offers longer protection (7 to 10+ years).  

    Anyone who previously received an NIP-funded Zostavax dose must wait 5 years to be eligible to receive an NIP-funded, 2-dose course of Shingrix. However, it can be safely administered as early as 12 months later if patients wish to purchase it privately. 

    People who previously received a self-funded dose of Zostavax, and who now meet the eligibility criteria for Shingrix, can receive an NIP-funded, 2-dose course of Shingrix 12 months after receiving Zostavax. 

  • Can people who have received 1 dose of privately funded Shingrix receive their second dose funded?

    If a NIP-eligible person previously purchased and received 1 dose of Shingrix privately they can complete the course with a funded dose of Shingrix.  

    Eligible groups are:  

    • First Nations Australians aged ≥ 50 years  
    • all adults from ≥ 65  years   
    • immunocompromised adults* from ≥ 18 years with certain medical conditions, including:  
      • history of haematopoietic stem cell transplant  
      • ghép tạng đặc  
      • blood cancer  
      • advanced or untreated HIV. 

  • How is Shingrix prepared and administered?

    Shingrix must be reconstituted prior to administering.   

    One dose of Shingrix (0.5mL) comes as 2 separate vials:   

    • Vial 1 is the adjuvant suspension  
    • Vial 2 is the antigen powder.   

    The contents of Vial 1 should be added to Vial 2 and the mixture gently swirled until the powder is dissolved.   

    The reconstituted vaccine has an opalescent, colourless to pale brown appearance.   

    Shingrix must be injected intramuscularly. 

  • How protective is Shingrix?

    Completing both doses of the 2-dose course is required for adequate protection. In those aged ≥ 50 years, Shingrix provides 97% protection against zoster in immunocompetent individuals and 91% protection in those aged > 70 years.  

    Clinical trials demonstrate high efficacy up to 4 years following vaccination. Immunogenicity data indicates that the level of efficacy is likely to persist beyond 10 years. 

  • If side effects were experienced following dose 1 of Shingrix what will the experience be following dose 2?

    The most common side effects following Shingrix vaccination include phản ứng tại chỗ tiêm, fatigue, myalgia (muscle pain), headaches and fever. These side effects are temporary and tend to last 1-3 days. Approximately 1 in 6 people find that these side effects are severe enough to limit regular strenuous activities during this time (e.g. swimming, gardening etc).  

    The experience of side effects following dose 1 of Shingrix does not mean that side effects are guaranteed to occur following dose 2 or be more significant following dose 2.  

    Completing both doses of the 2-dose course of vaccination is required for adequate protection against the development of zoster and its complications.  

  • Do zoster vaccines need to be reported to the Australian Immunisation Register (AIR)?

    It is mandatory to report all NIP vaccinations, including zoster vaccination, to the Australian Immunisation Register. 

    It is important that immunisation records are accurately maintained and reviewed prior to vaccine administration to avoid any dosing errors. Patient recall is not always reliable; it is therefore essential to review an individual’s immunisation records. 

Nguồn tài liệu

Các tác giả: Nigel Crawford (Director, SAEFVIC, Murdoch Children’s Research Institute) and Georgina Lewis (Clinical manager, SAEFVIC, Murdoch Children’s Research Institute)

Đượcxem xét bởi: Nigel Crawford (Director, SAEFVIC, Murdoch Children’s Research Institute), Rachael McGuire (MVEC Education Nurse Coordinator) and Katie Butler (MVEC Education Nurse Coordinator)

Ngày: November 2023

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You should not consider the information on this site to be specific, professional medical advice for your personal health or for your family’s personal health. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult a healthcare professional.

qua Rachel McGuire