No 39 - 2013

Influenza vaccination 2013/2014

1 October marks the beginning of the 2013/14 influenza season and therefore also the introduction of the free influenza vaccination offer to select population groups.

Last year's influenza season was characterised by a remarkably prolonged period with increased influenza activity due to influenza A as well as influenza B. In some periods, this constituted a considerable burden on Danish healthcare and caused excess mortality among the elderly.

This underlines the importance of increasing the influenza vaccination coverage, particularly among risk groups and persons aged 65 years and older. The WHO's objective is a 75% coverage in the latter age group in 2012/2013; however, coverage in Denmark only constituted 46%.

Free influenza vaccination

In accordance with Executive Order of 04 September 2013 on free influenza vaccination to select population groups, the following persons residing in Denmark are entitled to free influenza vaccination: 

• Persons who at the time of the vaccination have reached the age of 65 years
• Early retirement pensioners
• Chronically ill persons who suffer from the following conditions, upon medical assessment: 
  - chronic pulmonary conditions
  - cardiovascular diseases (barring high blood pressure with no concurrent conditions)
  - diabetes 1 or 2
  - congenital or acquired immunodeficiency
  - patients whose respiration is affected due to muscular weakness
  - chronic liver or kidney failure
  - other chronic diseases which, according to the physician’s assessment, pose a serious health risk in conjunction with influenza
• Severely obese persons (recommended BMI > 40) upon medical assessment
• Persons with other serious diseases which, according to the doctor’s assessment, pose a serious health risk in conjunction with influenza.
• Pregnant women in their 2nd or 3rd trimester
• Household contacts to severely immunosuppressed patients (congenital or acquired immune deficiency) upon medical assessment

The Danish Health and Medicines Authority has prepared a guideline for physicians on free influenza vaccination. The guideline is available (in Danish language) at www.retsinformation.dk.

The offer of free vaccination runs from 1 October until the end of 2013. For pregnant women in their second or third trimester, the offer remains in place until the end of March 2014.

Information

As in previous years, the Danish Health and Medicines Authority will run a campaign to inform risk groups of influenza vaccination. In August, posters and other material were sent to GPs, municipalities, pharmacies and midwife centres.

Extra posters and visiting cards on influenza vaccination may be ordered at Schultz Distribution on phone: 70 26 26 36. Furthermore, information letters targeting patients at risk and the remaining materials are avaliable for download (in Danish language) at the following website: www.beskytdigmodinfluenza.dk, under the portal targeting municipalities and health professionals.

Furthermore, the campaign consists of TV ads on national Danish TV and in pharmacies in weeks 39, 40 and 41, ads in weekly magazines and on relevant websites and a broad press campaign targeting national as well as local media.

Delivery

This year a total of three vaccine products were ordered (Fluarix, Inflexal og Vaxigrip) from three manufacturers. All three vaccines contain components of inactivated influenza virus and they are considered equal with respect to protection against influenza.

None of the vaccines contain thiomersal or adjuvant. For children aged from six months to five years, Fluarix and Vaxigrip are recommended for first-line treatment, see below. For more detailed information on the individual products and "Questions & Answers", please see www.ssi.dk.

Influenza vaccines in the 2013/2014 season

The vaccines' composition was based on the WHO's recommendations and contains antigens from three seasonal influenza viruses which are in circulation globally:

This year, the composition was adjusted to the following:

• A/California/7/2009 (H1N1)pdm09-like virus
• A/Victoria/361/2011 (H3N2)-like virus with changed antigen characteristics corresponding to the cell-cultured prototype virus
• B/ Massachusetts/2/2012-like virus (the Yamagata line)

Children

Children above the age of six months with a risk of a serious influenza course should be vaccinated. In the majority of cases, such children are monitored by a paediatric clinic, but they may also receive free vaccination at a specialist or at a vaccination clinic.

A guideline from the Danish Paediatric Society is available for download (in Danish) at www.paediatri.dk.

Children aged from six months to eight years who have not previously been vaccinated against influenza should receive two vaccinations at a minimum interval of four week. Children aged 6-35 months are vaccinated using only half the vaccine dose.

Inflexal is associated with an increased risk of fever in children aged from six months to five years. Fluarix and Vaxigrip are therefore recommended as first-line treatment for this age group. From five years of age, all three inactivated vaccines are considered equal.

It may be relevant to vaccinate household contacts and other persons who come into close contact with children belonging to the risk groups.

Pregnancy and breast-feeding

Pregnant women are at increased tisk of suffering serious complications from influenza infection compared with non-pregnant women, and this has been particularly evident for influenza A(H1N1)pdm09, which has been in circulation since 2009.

Influenza vaccination is therefore recommended for all pregnant women in their second or third trimesters. Pregnant women in their first trimester of pregnancy are also vaccinated, provided they belong to a risk group.

Many years of global experience with vaccination of pregnant women have demonstrated that influenza vaccination during pregnancy is safe for the child and not associated with an increased risk of adverse reactions for the pregnant woman. Influenza vaccines may also be given during the period of breastfeeding.

Disseminated sclerosis and HIV

Patients with disseminated sclerosis may risk having new attacks if their disease is complicated by influenza. A risk of new attacks as a result of vaccination has not been observed. Guidance concerning vaccination of HIV-infected patients is available from the infectious diseases department where the patient attends follow-up.

Degree of protection

Immunity achieved through vaccination with inactivated influenza virus is generally effective 2-3 weeks after vaccination and the effect generally lasts 6-12 months. The degree of protection is, in particular, dependent on the correlation between the type of virus in circulation and the virus strains in the vaccine.

In young, healthy persons, vaccination prevents up to 70-90% of influenza cases. In elderly persons, protection against ordinary influenza illness is somewhat lower. Protection against serious complications, hospital admissions and death in the elderly is up to 60%.

Adverse reactions and contraindications

Fever, malaise, shivers and tiredness are common reactions which typically recede after 1-2 days. The inactivated influenza vaccines do not cause influenza illness.

Persons who are hypersensitive to chicken eggs/chicken protein or other vaccine ingredients who previously experienced an anaphylactic reaction should not be vaccinated. Allergy to formaldehyde will most frequently manifest itself as contact dermatitis in connection with which patch tests may be positive; however, this does not constitute a contraindication. To avoid such reaction, the vaccine may be administered intramuscularly.

Neuroaminidase inhibitors may be used prophylactically in persons who are unvaccinated due to contraindications and in unvaccinated contacts.

Influenza surveillance

The influenza surveillance performed by Statens Serum Institut will be in place as from Week 40. INFLUENZA-NEWS including weekly updates on national Danish as well as international influenza incidence will start being published once the initial signs of influenza activity have been observed.
(T.G. Krause, L.K. Knudsen, Department of Infectious Disease Epidemiology)

Pneumococcal vaccination of persons at increased risk of invasive pneumococcal disease

The Department of Infectious Disease Epidemiology has received a number of enquiries concerning recommendations on the use of 13 valent conjugate pneumococcal vaccine in some patient groups.

We therefore take this opportunity to clarify that the Danish Health and Medicines Authority provides a limited subsidy (Danish: klausuleret tilskud) for some patient groups covering both the 13 valent and the 23 valent conjugate pneumococcal vaccine, EPI-NEWS 51b/12.

Since 1997, a guideline from Statens Serum Institut has stated that persons above 65 years of age and patients with other medical risk factors who are not currently eligible for the subsidy may benefit from vaccination with the 23 valent conjugate pneumococcal vaccine, EPI-NEWS 51/96, 40/98, 44/99, 39/01 and 46/02.

As the 13 valent conjugate pneumococcal vaccine has also been approved for use in adults and in the elderly, a proposal has been prepared describing how these patient groups should receive vaccination, EPI-NEWS 51b/12.

As opposed to the provisions which are applicable to influenza vaccination, the Danish Health and Medicines Authority has not published a general recommendation on pneumococcal vaccination of persons above 65 years of age, and therefore the vaccination is not avaliable free of charge either to this group or to other groups with medical risk factors who are not comprised by the subsidy.
(Department of Infectious Disease Epidemiology)

Limitation of the right of issue for Lariam®

Mefloquine is indicated for malaria prophylaxis in connection with travels to areas with widespread chloroquine resistance, EPI-NEWS 26b/13. Earlier this year, the Danish Health and Medicines Authority limited the the right of issue for Lariam® (mefloquine) to specialists of infectious medicine or clinical microbiology.

Furthermore, Lariam® is now part of a risk minimization programme which - among others - comprises information to health staff, including a check-list detailing five contraindications:

• hypersensitivity to mefloquine or related compounds,
• previous or present neuropsychiatric conditions
• previous blackwater fever
• severe hepatic impairment
• current halofantrine treatment

The program also requires that a patient card be completed.

When prescribing Lariam®, it is therefore important to thoroughly describe to the patient the neuropsychiatric profile of mefloquine, to inform the patient that he or she should read the package leaflet and to hand out a patient card.
(Department of Infectious Disease Epidemiology)

Link to previous issues of EPI-NEWS

25 September 2013