Mpox (monkeypox)

Key messages

• Mpox (formerly monkeypox) is a disease caused by infection with the monkeypox virus and is an urgent notifiable condition in Victoria.
• Since May 2022, there has been a multi-country outbreak of mpox which has mostly impacted gay, bisexual and other men who have sex with men.
• In Victoria, the risk of local transmission and transmission linked to international travel remains.
• Mpox can be spread from person-to-person through skin-to-skin contact, contaminated surfaces, and respiratory droplets.
• Symptoms include rash, fever, chills, tiredness, headache, sore throat, muscle aches and swollen lymph nodes. Proctitis or urethritis can also occur.
• Clinicians should test for mpox in all patients presenting with compatible symptoms. Cases of mpox can occur in fully vaccinated or partially vaccinated individuals, and clinicians should be alert to the possibility of atypical or attenuated presentations.
• Vaccination can protect against infection and severe disease. Free mpox vaccine is widely available for eligible people through sexual health clinics, public hospitals, general practitioners, Aboriginal health services, pharmacies and some local councils.

Notification requirement for mpox

Mpox is an urgent notifiable condition.

Notify any suspected or confirmed case to the Department of Health by telephone as soon as practicable and within 24 hours by calling 1300 651 160 (24/7).

Medical practitioners do not require approval to test for mpox.

Infectious agent of mpox

Mpox is caused by the monkeypox virus, a poxvirus of the Orthopoxvirus genus in the Poxviridae family.

Identification of mpox

Clinical features

Symptoms of mpox can include a rash, swollen lymph nodes, fever, chills, headache, sore throat, muscle aches, joint pain and exhaustion. Non-rash symptoms may precede or accompany the rash. Some people with mpox experience proctitis (which may present with anal or rectal pain, bloody stools, diarrhoea) or urethritis.

Atypical or attenuated clinical presentations can occur particularly in fully or partially vaccinated people.

The rash mainly affects the genital or perianal areas, face, including inside the mouth, and extremities such as hands and arms or feet and legs, however other parts of the body can be affected. The rash may change and go through different stages and involve skin lesions such as vesicles, pustules, pimples, or ulcers which become scabs that fall off.

People with mpox are considered infectious from the first onset of symptoms until all skin lesions crust, scab and fall off with a layer of new skin forming underneath.

Symptoms may resemble sexually transmitted infections (STIs). In patients presenting with genital or anal lesions and symptoms, testing for other STIs including herpes simplex virus, syphilis, chlamydia and gonorrhoea is recommended.

Symptoms of mpox usually begin within 21 days after exposure. Symptoms typically last for 2-4 weeks. Mpox illness is typically mild, however, some people may develop severe illness and require hospitalisation. Children, pregnant women, and immunocompromised people are considered at higher risk of developing severe disease.

Diagnosis

Diagnosis is confirmed by polymerase chain reaction (PCR).

Suitable samples include a swab or other specimen of rash lesion material (fluid or base of lesion). Other samples can include anorectal swab for patients presenting with proctitis and pharyngeal swabs. For further information on sampling, contact the Local Public Health Unit or refer to the Public Health Laboratory Network resources.

Sampling procedures may vary depending on the location and phase of the rash or other presenting symptoms, and specific packaging and transport of samples are required.

Wear appropriate personal protective equipment (PPE) when collecting samples. This includes fluid repellent surgical mask, gloves, disposable fluid resistant gown, and eye protection – face shields or goggles.

Clinicians should consider the possibility of mpox as well as alternative diagnoses such as measles, varicella zoster, syphilis, herpes simplex, chancroid, molluscum contagiosum, and lymphogranuloma venereum. As symptoms may resemble other STIs, testing should be considered as part of investigation of differential diagnoses based on individual risk assessment.

Incubation period of mpox

The incubation period is typically 7 to 14 days with a range of 5 to 21 days.

Public health significance and occurrence of mpox

Mpox is endemic in central and west Africa, often in proximity to tropical rainforests, and has been increasingly appearing in urban areas.

In recent years, the number of cases and geographic spread of mpox has increased and is thought to be related to increasing urbanisation and decreasing population immunity following the cessation of smallpox vaccination programs. Smallpox vaccines are proven to be protective against other orthopoxviruses including monkeypox virus.

Since May 2022, a multi-country outbreak of mpox has been reported involving regions that are not endemic for mpox, including Australia. The outbreak has primarily impacted gay, bisexual and other men who have sex with men, particularly those who are travelling to outbreak areas, have multiple sexual partners or attend large parties or sex on premises venues.

Transmission of mpox

Person-to-person transmission occurs with prolonged physical or intimate contact with infected people (such as skin-to skin contact during sexual contact) and can also spread through respiratory droplets and contact with contaminated surfaces and objects (such as contaminated clothing, towels, or bedding). Vertical transmission from infected pregnant persons and transmission from infected animals (when hunting, skinning, or cooking them) has previously been documented in endemic regions.

Period of communicability of mpox

People are infectious from the time that they develop their first symptoms (which may be a fever or a rash) and until all skin lesions crust, scab and fall off with a layer of new skin forming underneath.

Susceptibility and resistance to mpox

Most people are not at risk of mpox.

In recent outbreaks, those most at risk have been gay, bisexual and other men who have sex with men, particularly those travelling to outbreak areas, have multiple sexual partners or attend large parties or sex on premises venues. These include newly sexually active people, and those who have experienced a shift in their sexual behaviour.

People who have previously been vaccinated against smallpox may have some immunity against mpox, however, may benefit from receiving mpox vaccine.

Control measures for mpox

Preventive measures

In addition to vaccination, mpox can be prevented through various measures, including:

• Avoiding close contact with people with suspected or confirmed mpox. This includes any potentially contaminated materials, such as bedding and towels, that have been in contact with an infected person.
• Maintaining good hygiene practices like washing hands with soap and water or cleaning hands with alcohol-based sanitiser.
• During local outbreaks it is recommended to consider limiting your number of sexual partners and ensuring that you have their contact details.
• It is also recommended to consider limiting sexual partners for three weeks after returning from overseas countries that have active outbreaks.

People who have had mpox should use condoms when having sex for 12 weeks after clearance.

Healthcare workers should implement both standard contact and droplet precautions. See ICEG interim guidance on Monkeypox for health workers.

For more information for men who have sex with men, visit Thorne Harbour Health website.

Vaccination

In Victoria, the mpox vaccine (JYNNEOS® vaccine) is available free-of-charge for eligible people.

Eligibility criteria

Post-exposure preventative vaccination (PEPV) preferably in 4 days, in accordance with clinical guidance from the Australian Technical Advisory Group on Immunisation for:

• High-risk contacts of mpox cases
• Attendees of SOPVs and public or private events (particularly where sexual or intimate contact may occur) in areas where local transmission of mpox is occurring.

Eligible people for primary preventative vaccination (PPV) include:

• Sexually active gay, bisexual or other men who have sex with men.
• Sexually active transgender and gender diverse people, if at risk of mpox exposure.
• Sex workers, particularly those whose clients are at risk of mpox exposure.
• Sexual partners (including anonymous or intimate contacts) of the above groups.
• Sex-on-premises venue staff and attendees.
• People living with HIV, if at risk of mpox exposure, and their partners.
• Laboratory personnel working with orthopoxviruses.
• Vaccination may also be considered for healthcare workers at risk of exposure to patients with mpox, based on local risk assessments. This may include primary care, sexual health clinics, hospital staff and others. The risk of transmission should also be minimised by using infection control measures.

Two doses are required for optimal protection and are provided subcutaneously 28 days apart. The mpox vaccine takes approximately 14 days before it is effective.

For more information on vaccination, see the Victorian mpox (monkeypox) vaccination program guidelines and the Australian Immunisation Handbook - Mpox.

How to access the vaccine

Free mpox vaccine is widely available for eligible people through Sexual Health Clinics, GPs, Aboriginal Health Services, public hospitals, community pharmacies and some local councils. People eligible for mpox vaccine can contact their Local Public Health Unit (LPHU) (using the map below) to find their local mpox vaccination provider.

Metro LPHUs

Regional LPHUs

Other locations

Please note while the vaccine is free, the consultation may not be. Speak to the immunisation provider to verify consultation-related fees and vaccine availability.

Immunisation providers can order mpox vaccine through Onelink online.

To register as a provider of government funded mpox vaccine refer to Ordering Vaccines.

For all other enquiries regarding the mpox vaccine, email immunisation@health.vic.gov.au.

Mpox eLearning module

Online training has been developed to educate immunisers about mpox immunisation before they can administer the vaccine in Victoria.

Please refer to the Secretary Approvals for pharmacist immunisers and intern pharmacist immunisers, nurse immunisers, and Aboriginal and Torres Strait Islander health practitioner immunisers for information about the scope and requirements of the authorisation.

Access the mpox eLearning module

When to get mpox vaccine

The best time for people to get the vaccine is before they are exposed to mpox. The vaccine takes approximately 14 days before it is effective. Individuals who have been vaccinated should follow public health advice to minimise their risk of contracting mpox during this time.

If a person is exposed to mpox, receiving a vaccination within 4 days after the first exposure will provide the highest chance of avoiding disease.

Anyone at-risk who is planning to travel to a country with a significant outbreak should be vaccinated 4-6 weeks before they depart to allow for maximum protection.

Control of case

Mpox typically results in a mild illness and most cases recover within a few weeks. Most cases will not require specific treatment other than supportive management or treatment of complications (e.g. antibiotics for secondary cellulitis).

Antivirals may be indicated for severe infections. Tecovirimat (TPOXX) is the preferred treatment for severe mpox virus infection.

Advice on clinical management, including antiviral treatment, should be sought from an infectious disease physician. Approval is required from the Deputy Chief Health Officer to access TPOXX from the National Medical Stockpile. Clinicians should contact the Department of Health on 1300 651 160 to request authorisation.

Restricting contact with others and following precautions are effective measures to reduce the spread of disease. Confirmed cases should restrict their interactions with others, especially those at high risk of severe disease from mpox, until all skin lesions have crusted, scabs have fallen off and a layer of new skin has formed underneath. People who have recovered from mpox should use condoms when engaging in sexual activity for 12 weeks after recovery.

Any person suspected to have mpox and undergoing testing should restrict their interactions with others while awaiting the result.

LPHUs will provide specific advice to cases regarding requirements to restrict interactions and follow precautions.

Control of contacts

Depending on the level of exposure, LPHUs may follow up contacts to advise them of their exposure, to monitor for symptoms, and follow precautions for 21 days following exposure. High-risk contacts may be recommended to receive post-exposure prophylaxis to reduce their risk of infection.

Post-exposure prophylaxis

Vaccination with an mpox vaccine or other post-exposure prophylaxis (including vaccinia immunoglobulin) may be recommended for certain contacts after a risk assessment, if there are no contraindications.

Post-exposure vaccination should be given preferably within 4 days of exposure to mpox, but can be given up to 14 days after last exposure based on a risk assessment. Contacts eligible for PEP will be referred by their LPHU to a health service for vaccination.

Control of environment

In healthcare settings, standard cleaning and disinfection procedures should be performed using a hospital-grade disinfectant with activity against viruses.

Activities such as dry dusting, sweeping, or vacuuming should be avoided to prevent dispersal of infectious particles.

Standard and transmission-based precautions, including the use of PPE, should be used when cleaning and disinfecting rooms of patients with suspected, probable, or confirmed mpox.

Resources for health professionals

The Australian Immunisation Handbook - Mpox

Community resources