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Final Issue: Volume 16 Number 51

Published on: 21 December 2006

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News Archives 9 February 2006

Last updated: Volume 16, No. 6 (PDF file, 468 KB)

Archives | News Archives 2006: Page 1| News 9 February 2006

News Archives: | 2006 | 2005 | 2004 | 2003

 

New case of transfusion-associated variant-CJD

A new case of probable variant Creutzfeldt-Jakob Disease (vCJD) has recently been diagnosed in a patient who received a blood transfusion from a donor who later developed vCJD (1). This is the third case of probable transfusion transmission of vCJD infection in the UK .

The first case of vCJD disease associated with blood transfusion was identified in December 2003. This individual developed vCJD six and a half years after transfusion of red cells donated by an individual who developed symptoms of vCJD three and a half years after donation (2). A case of vCJD 'infection' was identified a few months later in a recipient of red cells from a donor who developed symptoms of vCJD 18 months after donation. This second case died from causes unrelated to vCJD five years after transfusion. Post-mortem investigations found abnormal prion protein in the spleen and a cervical lymph node, but not in the brain, and no pathological features of vCJD were found (3). The new case developed vCJD nearly eight years after receiving a transfusion of red blood cells from a donor who developed vCJD about 20 months after donating this blood (1). Each of the three infected recipients received blood from different donors.

To date, 160 cases of vCJD have been identified in the United Kingdom . A collaborative study between the National Blood Services, the National CJD Surveillance Unit, and the Office for National Statistics has been underway since 1997 to collect evidence about transmission of CJD or vCJD via the blood supply (4). Review of data at blood centres has found records for 23 of the 160 vCJD cases (prior to their vCJD diagnosis). For 18 of these 23 cases, blood components were issued to hospitals for transfusion, and 66 recipients of these vCJD-implicated blood components have been identified. Forty of these 66 recipients have died, including the two known to have evidence of vCJD infection (2,3). The small group of living recipients of vCJD-implicated blood transfusion have been informed of their potential exposure to vCJD by blood transfusion. Some were contacted in late 2003/early 2004, and some in 2005. They were asked to take certain precautions to reduce the risk of onward person-to-person transmission of vCJD during healthcare.

All three infected recipients identified to date received non-leucodepleted red blood cells. Since October 1999, leucocytes have been removed from all blood used for transfusion in the UK . The effect of leucodepletion on the reduction of the risk of transmission of vCJD from an infected donor is uncertain.

The risk of vCJD infectivity in blood has also resulted in other groups being identified as 'at risk of vCJD for public health purposes' increased risk of vCJD, and being informed and asked to take public health precautions. These include certain recipients of plasma-products (5), individuals who have donated blood to vCJD cases (6), and certain recipients of blood from donors to vCJD cases (7). To date, there have been no vCJD cases associated with receipt of plasma-products, or among these other groups that have been categorises as 'at risk'.

This third case of vCJD infection associated with blood transfusion provides further evidence that vCJD can be transmitted between humans by blood transfusion, although much remains unknown. This reinforces the importance of the existing precautions that have been introduced to reduce the risk of transmission of vCJD infection by blood and blood products (8).

Reference

  1. Health Protection Agency. New case of variant CJD associated with blood transfusion (press release). London : HPA, 9 February 2006. Available at <http://www.hpa.org.uk/hpa/news/articles/press_releases/2006/060209_cjd.htm>.
  2. Llewelyn CA, Hewitt PE, Knight RSG, Amar K, Cousens S, Mackenzie J, et al. Possible transmission of variant CJD disease by blood transfusion. 2004 Lancet 363 ;417-21.
  3. Peden AH, Head MW, Ritchie DL, Bell JE, Ironside JW. Preclinical vCJD after blood transfusion in a PRNP codon 129 heterozygous patient. 2004 Lancet 364 ;527-9.
  4. Transfusion medicine epidemiology review (TMER) [online] 2005 [cited 9 February 2006]. Available at < http://www.cjd.ed.ac.uk/TMER/TMER.htm >.
  5. DH announcement: Plasma product recipients; Patient Notification Exercise Begins Reference number: 2004/0329. London : Department of Health, 9 September 2004. Available at < http://www.dh.gov.uk/PublicationsAndStatistics/PressReleases/PressReleasesNotices/fs/en? CONTENT_ID=4088953&chk=4BSn4F >.
  6. DH announcement: Notification exercise begins to reduce risk of vCJD transmission Reference number: 2005/0256. London : Department of Health, 20 July 2004. Available at < http://www.dh.gov.uk/PublicationsAndStatistics/PressReleases/PressReleasesNotices/fs/en? CONTENT_ID=4116206&chk=4YsTe9 >.
  7. DH announcement: Next stage of notification exercise to reduce risk of variant CJD transmission begins. Reference number: 2005/0404. London : Department of Health, 17 November 2005. Available at < http://www.dh.gov.uk/PublicationsAndStatistics/PressReleases/PressReleasesNotices/fs/en? CONTENT_ID=4123496&chk=UnGWvb >.
  8. DH announcement: Further precautions to protect blood supply Reference number: 2004/0104. London : Department of Health, 16 March 2004. Available at <http://www.dh.gov.uk/PublicationsAndStatistics/PressReleases/PressReleasesNotices/fs/en? CONTENT_ID=4076608&chk=MTwE%>

Use of antiviral drugs (Oseltamivir) for influenza

On 9 February 2006 the UK Department of Health issued a letter to all general practitioners in England to inform them that the use of antiviral drugs for the treatment or prophylaxis of influenza was now recommended, in line with the NICE guidance (http://www.nice.org.uk). The most recent influenza surveillance data for England shows that the overall rate for influenza has exceeded the threshold at which the use of antivirals is triggered. The overall GP consultation rate for influenza-like illness in England and Wales , based on RCGP data, has increased from 17.9 per 100,000 in week 04/2006 to 38.2 per 100,000 in week 05/2006. The rise in the consultation rate is most evident in children aged 5 to 14 years, where influenza B has been confirmed as the cause of many outbreaks among this age group.

 

Regional and national analyses of the Department of Health’s mandatory Staphylococcus aureus surveillance scheme in England: April 2001 to September 2005

Results of the Department of Health's mandatory methicillin resistant Staphylococcus aureus (MRSA) surveillance system in acute Trusts in England have been published for the period April to September 2005. Results for the first four years of the mandatory surveillance system (April 2001 to March 2005) are also included.

 

Figure 1 Number of MSSA and MRSA bacteraemia reports in England between April 2001 and September 2005

 

Further graphs and tables can be found on the S. aureus page of the HPA website at http://www.hpa.org.uk/infections/topics_az/staphylo/data.htm.

Introduction of pneumococcal vaccine into the childhood immunisation schedule, and changes to the meningitis C and Hib schedules

The Department of Health has announced changes to the childhood immunisation schedule (ref). Pneumococcal vaccine is being added to the schedule at 2, 4, and 13 months. There are around 5000 cases of invasive pneumococcal disease in England and Wales each year, around 530 of these in children under two years. Since the introduction of a similar programme in the United States, cases in young children caused by the strains in the vaccine have fallen by 94%, and cases in the over 65s have dropped by two thirds.

Two other changes will maximise protection against meningitis C and Hib disease. Firstly, MenC vaccine will be given at three and four months and a booster will be given at 12 months, instead of the current schedule of 2, 3 and 4 months of age. The latest evidence shows that the protection offered wanes one year after vaccination, and the change will maximise the protection in the first two years of life when the risk of infection is high. Secondly, a booster dose of Hib vaccine will be given at 12 months. Hib vaccine was introduced in 1992 and is currently given to children at 2, 3, and 4 months of age. Since 1999, there has been a small but gradual increase in the number of cases in older children being reported. Again, this is due to the protection offered by the vaccine waning over time. In 2003, there was a Hib booster campaign when a booster dose was given to older children to boost their immunity and reverse the increase. A booster dose of Hib vaccine is now being added to the childhood immunisation programme at 12 months to extend protection against Hib disease.

The new routine vaccination schedule will therefore be:

2 months DTaP/IPV/Hib + pneumococcal vaccine

3 months DTaP/IPVHib + MenC vaccine

4 months DTaP/IPV/Hib + MenC + pneumococcal vaccine

12 months Hib/Men C

13 months MMR + pneumococcal vaccine

Information about the changes to the routine programme can be found on the immunisation website at http://www.immunisation.nhs.uk.

Reference

  1. Department of Health. Pneumococcal vaccine added to the childhood immunisation programme; more protection against meningitis and septicaemia (press release). London : Department of Health, 8 February 2006. Available at <http://www.dh.gov.uk/PublicationsAndStatistics/PressReleases/PressReleasesNotices/fs/en? CONTENT_ID=4128036&chk=PI8e57>

 

Chikungunya virus in the Indian Ocean

Since the beginning of 2005, large numbers of cases of Chikungunya virus have been seen throughout the islands of the Indian Ocean . The first outbreak was noted in the Comoros Islands in early 2005, where over 5000 cases were reported between January and March (1). In March 2005, outbreaks began in the islands of Réunion, Mayotte, and Mauritius and have been ongoing; since November 2005, cases have also been reported in the Seychelles

Réunion

Between 28 March 2005 and 8 January 2006, 7438 confirmed and suspected cases have been reported in Réunion. The outbreak appears to have spread to all areas of the island (excluding higher altitude areas where vector transmission is low) from the north to the south according to cluster analysis (1). The number of cases reported is thought to be underestimated and mathematical models have estimated the number of cases to be nearer 50,000. The rapid increase in cases in 2006 has coincided with the onset of the southern hemisphere summer, providing ideal conditions for the mosquito vector to proliferate. One death has occurred in a ten year-old boy, which has been attributed to chikungunya virus based on clinical examination, as a post mortem was not performed (2).

Mayotte

Since the beginning of 2006, tens of cases have been reported, three of which have been laboratory confirmed (3). Reports in the media suggest over 50 cases have been seen (4).

Mauritius

In January 2006, 15 cases of chikungunya infection were reported in Mauritius . The majority of these cases have been associated with travel to Reunion , although since 23 January some cases have been reported with no relevant travel history. This suggests that secondary transmission is now occurring (5).

Seychelles

Cases were first reported in November 2005, and up to the end of January 2006, over 2000 cases were reported (6).

Chikungunya virus is an alphavirus of the Togaviridae family; it is principally transmitted by the Aedes aegypti mosquito. The symptoms of the virus are similar to dengue fever, with rapid onset of fever, headache, rigors, photophobia, sore throat, and conjunctivitis. After initial symptoms severe pains occurs in the joints, especially at sites of previous injury (7). Illness may last between one week and several months but is usually self-limiting. Death associated with Chikungunya had never been documented until this current outbreak.

The Seychelles and Mauritius are popular holiday destinations with British travellers and during the northern hemisphere winter about 1,200 British tourists visit the Seychelles and 6,000 visit Mauritius every month [Federation of Tour Operators, personal communication, 7 February 2006]. Réunion and Mayotte are more popular with French travellers as they are French dependencies.

There is no vaccine for chikungunya virus, therefore prevention relies on mosquito bite avoidance (http://www.nathnac.org/pro/factsheets/iba.htm) particularly during daylight hours when Aedes aegypti mosquitoes are active (8).

 

References

  1. C Paquet, I Quatresous, J-L Solet, D Sissoko, P Renault, V Pierre et al. Chikungunya outbreak in Réunion: epidemiology and surveillance, 2005 to early January 2006. Eurosurveillance weekly release 2 February 2006: 11 (2). Available at <http://www.eurosurveillance.org/ew/2006/060202.asp#2>.
  2. ProMED-mail. Chikungunya - Mauritius and Reunion Island (08): Reunion , 5 February 2006; 20060205.0378 [online]. Available at < http://www.promedmail.org/pls/promed/f?p=2400:1001:71123875547331111::NO::F2400_
    P1001_ BACK_PAGE,F2400_P1001_PUB_MAI>.L_ID:1000,31895
  3. Institut de Veille Sanitaire. Epidémie de Chikungunya . Point de situation au 7 septembre 2005 [online] [cited 7 February 2006] . Available at < http://www.invs.sante.fr/display/?doc=presse/2005/le_point_sur/chikungunya_070905
    /index.html >.
  4. 56 cas de chikungunya recensés à Mayotte en 2006 . Page on voila.fr website [online] 31 January 2006 [cited 9 February 2006] Available at <http://actu.voila.fr/Depeche/ext--francais--ftmms--sante/060131201004.iz7vv26u.html>.
  5. ProMED-mail. Chikungunya - Mauritius and Reunion Island (07): Reunion , 4 February 2006; 20060204.0358 [online] . Available on line at <http://www.promedmail.org/pls/promed/f?p=2400:1001:7914237415148705279::NO::F2400_ P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1010,31875>.
  6. ProMED-mail. Chikungunya - Seychelles , 3 February 2006 [online] . Available at: <http://www.promedmail.org/pls/promed/f?p=2400:1202:4895229872098395377::NO::F2400_ P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,31868>.
  7. Berger SA, Calisher CH, Keystone JS. Chikungunya virus infection. In: Exotic viral diseases: a global guide. Hamilton , London : BC Decker; 2003.
  8. National Travel Health Network and Centre . Chikungunya virus - Reunion , Mauritius and Seychelles - 7 February 2006 [online] [cited 7 February 2006]. Available at <http://www.nathnac.org/pro/clinical_updates/chik_070206.htm>.