No 9 - 2024

Two new measles cases detected in the Central Denmark Region

This week, the Department of Clinical Microbiology at Aarhus University Hospital detected two new measles cases in an adult and a child residing in the Central Denmark Region. The two cases are not considered to be related. These are the fourth and fifth detected cases of measles this year. The five cases were detected in a total of three Danish regions.

The adult has no travel activity and no known contact to any measles case. Therefore, the SSI assesses that Denmark is currently experiencing a low level of unacknowledged measles transmission. The child has a sibling who experienced fever and a rash earlier in February. The sibling, however, did not undergo measles testing. The sibling is now being tested for signs of recent measles infection. In late January, both children travelled abroad. Therefore, if recent measles infection is established in the other sibling, the infection of both children may be travel-associated.

As previously, physicians are encouraged to remain extra attentive to the measles diagnosis in weeks to come, EPI-NEWS 7-8/2024. The SSI will receive samples from the two detected cases, and therefore the origin of the infection may possibly be established in more detail.

The Danish Patient Safety Authority has been informed and has initiated and ensured infection tracing measures in relation to the contacts of the infected persons, privately as well as any healthcare contacts who may have been exposed to infection before the infected persons were diagnosed.

It is important that any person who is suspected of having measles avoids being in waiting rooms with other patients as measles is extremely infectious.

Sampling

On suspicion of measles, the following samples should be taken:

1. Pharyngeal swab and urine for detection of measles virus (morbili virus) RNA by PCR. The greatest possibility for detecting measles virus is in the early phases of the disease course, but the virus is frequently detectable for several weeks after the acute disease occurs. A negative finding does not exclude measles.
   
   
2. A blood sample for measles virus IgM/IgG antibody determination. IgM antibodies may be confirmed by rash.

We recommend that all measles virus-positive samples be sent to the National WHO Reference Laboratory for Morbilli and Rubella, Laboratory for Virus Surveillance and Research, SSI, for characterisation, which is free of charge.

On suspicion of measles disease, it is important that the diagnostics and work-up are performed as rapidly as possible with a view to continued isolation of the patient and also tracking and, if relevant, treatment of any non-immune persons who may have become exposed to infection. Serological detection is insufficient for measles diagnostics, and virus detection by PCR is necessary.

Virus detection by PCR analysis is the quickest and safest method for laboratory diagnostics of measles. The analysis is currently only available at the SSI and at DCM Aarhus University Hospital.

The National WHO Reference Laboratory for Measles and Rubella at the SSI handles the characterisation (sequencing and typing) of all measles virus-RNA-positive samples in Denmark. As characterisation of the measles virus is important in relation to infection tracing and mapping, all suspected and confirmed measles virus-positive samples should be forwarded to the Reference Laboratory as quickly as is practically possible. We recommend contact by phone to the virologist in charge at the SSI (in the daytime pho.: 40336379, after 15.30 to the epidemiologist on call pho.: 41317404) to inform the laboratory that samples are underway and thereby avoid any unnecessary delay of the diagnosis.

For further details, please see the SSI's measles theme page.

Vaccination and prophylaxis following exposure

The primary form of prevention is MMR vaccination. In Denmark, MMR vaccination is offered to all children at 15 months and four years of age as part of the Danish childhood vaccination programme. Currently, no recommendation has been made to advance the time of vaccination. However, upon request, the initial MMR vaccine may be given as from 12 months of age and will then still count as part of the vaccination programme, also if given concurrently with the third Pentavac and the third Prevenar13.

Persons aged 18 years or more who have not previously had measles or received vaccination may be vaccinated free of charge. Vaccination is given as a single MMR vaccine, EPI-NEWS no. 7-8/2024.

Following certain exposure to infection, i.e. contact to a laboratory-confirmed or epidemiologically linked case, MMR vaccination may be given within three days of exposure to infection and normal human immunoglobulin within six days as post-exposure prophylaxis (PEP) to non-immune contacts. The local unit of Supervision and Guidance of the Danish Patient Safety Authority delimits and informs any vulnerable contacts who are at risk of becoming infected with measles. These contacts are informed of the possibility of receiving PEP. The clinical physicians assess, if needed in collaboration with the SSI, whether PEP is indicated in each case. Subsequently, expenses are reimbursed by the regional authorities.

For more details on post-exposure prophylaxis, please see here.

Notification

As from 1 November 2023, measles is notifiable by phone to the Danish Patient Safety Authority, Supervision and Guidance East/West in case of enhanced suspicion or confirmed measles disease, EPI-NEWS no. 44b/2023. Additionally, confirmed measles cases are notifiable in writing to the Danish Patient Safety Authority, Division for Supervision and Guidance East/West as well as to the SSI. Notification is made via the electronic notification system (SEI2). See link for further information and guidance.

(B.B. Jensen, K.T. Franck, L.D. Rasmussen, Virus Monitoring & Research, National Reference Laboratory for Measles and Rubella, L.K. Knudsen, J. Grau. P.H. Andersen, Department of Infectious Disease Epidemiology and Prevention, M. Kragh Thomsen, DCM Aarhus University Hospital, A. Hempel Jørgensen, Danish Patient Safety Authority, Supervision and Guidance West)

Gonococcal culture and susceptibility testing: Amended guideline in the Capital Region of Denmark and Region Zealand

Swabbing for gonococcal culture and susceptibility testing may, in the vast majority of cases, be limited to a single anatomical localisation as infection with several gonococcal strains with different susceptibility patterns occurs very rarely.

See the recently amended sampling and treatment guideline: Treatment of gonorrhoea (in Danish language)

(S. Hoffmann, Bacteria, Parasites & Fungi)