No 48 - 2010

Mycoplasma pneumoniae epidemic

In EPI-NEWS 40/10 and EPI-NEWS 41/10, an increase in the number of tests positive for Mycoplasma pneumoniae (MP) by PCR was described.

Over the past weeks, a further increase was observed across the country both in absolute numbers and in the percentage of positive specimens. This confirms that we are witnessing a national epidemic.

Figure 1 shows the overall number of positive specimens and the percentage of positive tests detected at the clinical microbiology departments that perform PCR for MP, i.e. Esbjerg, Herlev, Hillerød, Hvidovre, Odense, Copenhagen University Hospital (Rigshospitalet), Skejby, Vejle, Viborg, Aalborg and the SSI from weeks 34-47.

Throughout the period, the number of positive specimens found during a 2-week-period has increased more than 10-fold (45 to 517) and the percentage of positives has doubled (from 9.6 to 19.0).
(S.A. Uldum, DBMP, J.N. Rasmussen, Department of Epidemiology)

World Aids Day

As previous years, 1 December marks the World AIDS day. This year's theme is "Act Aware". The theme encourages awareness of the fact that you may protect yourself and the people you care for against HIV through safe sex.

The theme is also an encouragement to become aware that you may help limit stigmatisation and erroneous conceptions of HIV. Many misconceptions of the ways in which HIV is transferred from one person to the next still exist and the belief that HIV is always fatal is widespread.

It should therefore be underlined that:

• HIV does not spread via normal contact between persons.
• HIV does not spread via saliva or tears
• HIV only spreads via blood and sex
• The risk of sexual infection is close to zero if the HIV-positive person is taking HIV medication as prescribed and does not suffer from other sexually transferred diseases.

HIV medication can keep HIV positives free of HIV disease for many years. Accordingly, in Denmark it is extremely rare that a HIV positive person who takes his/her medication as prescribed develops AIDS, EPI-NEWS 45/10.

Today, HIV positives have approximately the same life expectancy as non-HIV positives.
Nevertheless, many have no knowledge of such pharmaceutical improvements and therefore fear of the HIV-infectees remains widespread. This unjustified fear causes infectees to feel isolated and impedes openness about HIV. Correspondingly, others who fear that they may have HIV may refrain from being tested due to fear of the social consequences in case they test positive.

In this manner, stigma, ignorance and fear are instrumental in underpinning the HIV epidemic, simply because HIV-infected persons who have not yet been diagnosed do not receive treatment. Furthermore, persons who do not receive treatment risk infecting their partners through sexual contact.
(S. Cowan, Dept. of Epidemiology)

Whooping cough vaccination prior to high school stays in the USA

Adolescents who are planning a stay at a high school in the USA may need to undergo vaccination which is more comprehensive than the Danish Childhood Vaccination Programme.

In recent years, a number of states have introduced a whooping cough vaccination requirement, and several general practitioners have experienced that a statement explaining the lack of revaccination against whooping cough as detailed in EPI-NEWS 20-21/05 (pdf), is not accepted by the American authorities or by individual high schools.
Whooping cough revaccination of adolescents is not available in Denmark. The only option of providing a whooping cough booster is to administer the DTaP-IPV Booster ("5-year vaccination"). This vaccine is not registered for use in newborns, adolescents or adults.

But in this specific situation and owing to the very limited risk of side effects, the vaccine may be given to adolescents provided this is an indispensable requirement.
General practitioners should pay attention to any whooping cough revaccination requirement before revaccination, so that the DTaP-IPV booster may be given in stead of the DT booster.

Revaccinations containing diphtheria or tetanus should not be administered at close intervals, and the absolute minimum interval is two years.
(G. St.-Martin, P.H. Andersen, Dept. of Epidemiology)

Increase in the Number of Mumps Cases

In 2010 the January-November period saw 30 mumps notifications. This is an increase compared with the 17 cases reported in 2009 and the 24 cases seen in 2008.

Among the 30 cases, six were children aged 6-17 years, fourteen were aged 18-30 years and ten were 31-62 years.

Two cases were infected abroad: one in France and one in Thailand.

The remaining 28 were infected in Denmark, including 18 from the Central Jutland Region, while the remaining cases were evenly distributed across the country.

Seven were infected by siblings or other known persons; in 21 cases the source of infection was unknown and in two cases the source was not stated.

A total of four had received one MMR vaccine, two had received two vaccines, 18 were unvaccinated and in six cases vaccination status was not stated.

Commentary

In Denmark and abroad, an increased occurrence of mumps has been observed among adults, who are at risk of more serious illness than children. Furthermore, it is well-known that the mumps component of the MMR vaccine is less effective than the remaining components and that vaccine faliure may occur.

The Danish National Board of Health recommends that unvaccinated adults born after 1974 who have not had measles, mumps or rubella receive MMR vaccination.

The MMR vaccination is free of charge for persons under 18 years. There is, in principle, no upper age limit for MMR vaccination.

The Medical Officer of Health of the Central Jutland Region has actively informed about these recommendations and the past two months have only seen a single notified case.

Prior to the 1987 introduction of the MMR vaccination in Denmark, mumps caused 200 children to be hospitalised with serous meningitis annually and a limited number of children suffered the sequelae of hearing loss.

Approx. a third of of the mumps cases in adolescent boys and adult males caused orchitis which in rare cases lead to sterility.

(L.K. Knudsen, P.H. Andersen, Dept. of Epidemiology)  

Individually notifiable diseases and selected laboratory diagnosed infections (pdf) 

1 December 2010