Download WHO recommendations for influenza virus

Eurosurveillance Weekly, funded by Directorate General Health and Consumer Protection of the European
Commission, is also available on the world wide web at <http://www.eurosurveillance.org/>. If you have any
questions, please contact Fiona Reid <[email protected]>, +44 (0)20-8200 6868 extension 3615.
Neither the European Commission nor any person acting on its behalf is liable for any use made of the
information published here.
Eurosurveillance Weekly: Thursday 7 February 2002. Volume 6, Issue 6
Contents:
1.
2.
3.
4.
5.
6.
Identification of a new subtype of influenza virus A(H1N2)
WHO recommendations for influenza virus vaccine 2002/03
First case of vCJD reported in Italy
Measles outbreak in North Jutland, Denmark
European Food Safety Authority becomes a reality
EuroHIV publishes latest data on HIV/AIDS surveillance in Europe
Identification of a new subtype of influenza virus A(H1N2)
A meeting of influenza experts at the World Health Organization (WHO) in Geneva this week has considered
the recent isolation of a new subtype of the influenza A virus, A(H1N2) (1). The meeting was held to review
the global influenza situation and decide the composition for the influenza vaccine for the northern
hemisphere for winter 2002/03, and was based on information from the WHO global influenza surveillance
programme and Public Health Laboratory Services (PHLS) surveillance of influenza in England and Wales.
In recent years, two subtypes of influenza A have been circulating and causing illness in humans: the H1N1
subtype and the H3N2 subtype. A new subtype, H1N2, has emerged which contains a haemagglutinin (H)
component which is very similar to that contained in the recent H1N1 strains and a neuraminidase (N)
component which is very similar to that contained in the currently circulating H3N2 strains. The new subtype
appears to have arisen by reassortment of the two human viruses.
The new subtype of the influenza A virus has so far been isolated from humans in England, Israel, and Egypt
in the last few weeks. A similar event occurred in China during the 1988/89 influenza season when a number
of influenza A(H1N2) isolates were detected which were determined to have arisen as a result of
reassortment. Further spread of these reassortant viruses in humans did not occur at that time (2-3).
References:
1.
2.
3.
PHLS. WHO announces the isolation of a new strain of influenza virus – A (H1N2), and the vaccine composition for next
winter. Press release, 6 February 2002. (http://www.phls.co.uk/news/bulletins/2002/020206id.htm)
Guo Y, Xu X, Cox NJ. Human influenza A (H1N2) viruses isolated from China. J Gen Virol 1992; 73: 383-8.
(http://vir.sgmjournals.org/)
Li XS, Zhao CY, Gao HM, Zhang YQ, Ishida M, Kanegae Y et al. Origin and evolutionary characteristics of antigenic
reassortant influenza A (H1N2) viruses isolated from man in China. J Gen Virol 1992; 73: 1329-37. (http://vir.sgmjournals.org/)
Reported by John Watson ([email protected]), Communicable Disease Surveillance Centre, PHLS, and
Maria Zambon ([email protected]), Central Public Health Laboratory, PHLS, London, England.
WHO recommendations for influenza virus vaccine 2002/03
The new subtype of the influenza A virus, A(H1N2), is a combination of components present in the strains of
the two influenza A subtypes (H1N1 and H3N2) currently contained in the vaccine, and so people who have
received the vaccine should have a good level of immunity to the new subtype. People in the general
population who have not been vaccinated should also have some immunity due to the circulation of the H1N1
and H3N2 subtypes over the last two decades.
This information has been taken into account in the discussions at the WHO in Geneva about the influenza
vaccine for next winter and is reflected in the components recommended for inclusion in the vaccine so that it
provides protection against the new virus subtype (1).
The strains of influenza virus recommended by WHO to be included in the 2002/03 vaccine are:
A/New Caledonia/20/99 (H1N1)-like virus
A/Moscow/10/99 (H3N2)-like virus: (the widely used vaccine strain is A/Panama/2007/99)
B/Hong Kong/330/2001 – a B Victoria-like virus
The H1N1 and H3N2 components are unchanged from the current vaccine and are considered to provide
good protection against the new influenza A H1N2 subtype.
Reference:
1.
World Health Organization. WHO urges influenza vaccination for northern hemisphere. WHO press release WHO/08, 6
February 2002. (http://www.who.int/inf/en/pr-2002-08.html)
Reported by John Watson ([email protected]), Communicable Disease Surveillance Centre, PHLS, and
Maria Zambon ([email protected]), Central Public Health Laboratory, PHLS, London, England.
First case of vCJD reported in Italy
The first case of variant Creutzfeld-Jakob Disease (vCJD) has been reported in Italy (1). The case from Sicily
was diagnosed in Italy and Great Britain on the basis of clinical and instrumental tests and tonsillar biopsy.
The Istituto Superiore di Sanità (ISS) has classified the case as probable, but since the patient is still alive,
the ISS has not released any additional information. The surveillance and reporting of CJD has been
mandatory in Italy since the beginning of 2002.
A ban on feeding mammalian protein to ruminants was approved on 28 July 1984, and enforced from 15
September that year. The prevalence of indigenous cases of bovine spongiform encephalopathy per 10 000
tests was 1.03 for the year 2001 (2).
References:
1.
2.
Ministero della Salute. Segnalato caso variante malattia Creutzfeldt-Jakob. Press release 05/02/2002 N° 40, 5 February 2002.
(http://www.sanita.interbusiness.it/comunicati_stampa/documenti/040-02.rtf)
Centro per lo Studio e le Ricerche sulle Encefalopatie Animali e Neuropatologie Comparate. Focolai BSE in Italia: 2001/2002.
(www.to.izs.it)
Reported by Stefania Salmaso ([email protected]), Istituto Superiore di Sanità, Italy
Measles outbreak in North Jutland, Denmark
Since the introduction of the measles, mumps, and rubella (MMR) vaccine, measles has occurred in
Denmark only rarely, and the most recent outbreak occurred in 1998 (1). At the end of December 2001,
however, an outbreak began in the county of North Jutland, where the index case, a 9 year old Danish child,
was admitted to hospital. The child had become infected on holiday in the Philippines. Up to 5 February 2002,
18 further cases of measles have been reported. Ten cases are younger than 2 years, one is in the 2-5 age
group, and eight are aged 6-10. The patients are distributed geographically across most of North Jutland,
although three live in Copenhagen. The diagnosis has been confirmed by finding measles specific IgM in 15
of a total of 19 patients; the remaining four patients had clinical symptoms of measles and are
epidemiologically linked to a serologically confirmed infection.
Vaccination status
Fifteen of the patients were unvaccinated, ten of these were younger than 2 years. Vaccination status is
uncertain or unknown for two of the patients. Two patients had received only one dose of MMR.
Transmission
Five of the patients had direct contact with the index case, and four had direct contact with one secondary
case. The means of transmission for the remaining patients is uncertain or unknown. It is known, however,
that four of these patients were simultaneously admitted or seen as outpatients in the children's department
of the hospital to which the index case had been admitted.
Comments
This outbreak emphasises the fact that the measles virus is highly infectious. As the most recent case was
diagnosed only in the past week, further cases cannot be excluded.
Vaccination coverage of MMR in Denmark has been reported to be very good, with 100% of children aged 110 years reported to have received one dose by 2000 (2). Vaccination coverage for the second dose was
reported to be lower at 91% overall. Most counties in Denmark have levels of 95% or more for the first dose;
coverage of the first dose in North Jutland was 99% and the second dose 92% in 2000. Age at vaccination is
not currently available routinely in Denmark. In 1997, however, coverage of one dose by 15 months of age
was 84% overall, ranging from 78-91% and below the 95% target recommended by the World Health
Organization (3). This is critical information for evaluating the causes of an outbreak. MMR must be given to
children when they are young enough for the programme to be effective at interrupting transmission; delayed
vaccination is equivalent to a fall in vaccination coverage.
Prophylaxis
The MMR vaccine is recommended as prophylaxis for children who have been exposed to infection, but it
should be given within 72 hours of exposure for antibodies to develop within the incubation period (4). In the
event of an outbreak of measles, vaccination of children >12 months is recommended. The vaccine can be
used even if the child has previously had mumps or rubella or both. Human normal immunoglobulin can be
used as prophylaxis or to attenuate the disease in patients aged >4 months who are susceptible to infection
and have been exposed within six days. Vaccination should not be carried out until at least three months after
immunoglobulin was administered.
References:
1.
2.
3.
4.
Glismann S, Christiansen AH. Measles 1990-2000. EPI-NEWS 2001; (9). (http://www.serum.dk/en/epi-nyt.uk/2001/week9.htm)
Christiansen AH, Rønne T. MMR vaccination 2000. EPI-NEWS 2001; (34). (http://www.serum.dk/en/epi-nyt.uk/2001/34.htm)
Christiansen M. MMR vaccination 1997. EPI-NEWS 1998; (23). (http://www.serum.dk/en/epi-nyt.uk/1998/week23.htm)
CDC. Measles, Mumps, and Rubella - Vaccine Use and Strategies for Elimination of Measles, Rubella, and Congenital Rubella
Syndrome and Control of Mumps: Recommendations of the Advisory Committee on Immunization Practices (ACIP). Morb
Mortal Wkly Rep MMWR 1998; 47: RR-08. (http://www.cdc.gov/mmwr/preview/mmwrhtml/00053391.htm)
Reported by Henrik Hamburger, Medical Office of Health, Aalborg, North Jutland; Annette Hartvig
Christiansen and Steffen Glismann ([email protected]), Department of Epidemiology, Statens Serum Institut,
Copenhagen, Denmark.
European Food Safety Authority becomes a reality
In December 2001, Eurosurveillance Weekly reported on the approval by the European Parliament of the
creation of an independent European Food Safety Authority (EFSA) (1). On 21 January 2002, the EFSA
became a reality when the Council of Ministers adopted the key legislation that provides the legal basis for
establishing the EFSA and general principles and requirements for European Union (EU) food law (2).
Immediately after the regulation 2002/178/EC (http://europa.eu.int/eurlex/en/dat/2002/l_031/l_03120020201en00010024.pdf) had been adopted, the Commission initiated some of
the practical measures that need to be taken. An interim team of Commission staff has started the process of
appointing the management board and an executive director. They will also ensure the continuation of
scientific advice until the EFSA scientific committee and the scientific panels of the authority are appointed.
Temporary quarters have been found to house the EFSA in Brussels.
The responsibilities of the EFSA will include the following (3).








Provision of independent scientific advice to support EU action on food safety, including all stages of
food production and supply.
Scientific evaluation of risks to the food chain, and any matter that may have a direct or indirect effect
on the safety of the food supply.
Collection, analysis, and exchange of scientific data through networks.
Safety evaluations of dossiers put forward by industry for EU level approval of substances or
processes.
Identification of emerging risks.
Scientific support to the Commission, particularly in the case of a food safety crisis.
Direct communication to the public on issues coming within its responsibility.
EFSA will be included in the rapid alert system, which will remain, as it is now, managed by the
Commission.
The authority could employ up to 250 people within three years to support EU food safety measures with
sound scientific advice. Working closely with – but independent of – the Commission, EFSA will assess risks
to the food chain and advise the Commission, which is responsible for managing those risks.
Further information can be found on the EFSA website at http://www.efsa.eu.int.
References:
1.
2.
3.
Little C. European Food Safety Authority approved. Eurosurveillance Weekly 2001; 5: 011220.
(http://www.eurosurv.org/update/011220.htm)
DG SANCO. European Food Safety Authority adopted - Council agrees key legislation putting a new European-wide food
safety system in place. DG SANCO press release IP/02/100, 21 January 2002.
http://europa.eu.int/rapid/start/cgi/guesten.ksh?p_action.gettxt=gt&doc=IP/02/100|0|RAPID&lg=EN&display=
Health and Consumer Protection DG. EFSA special. Consumer Voice 2002; 1: 2.
(http://europa.eu.int/comm/dgs/health_consumer/newsletter/200201/index_en.htm)
Reported by Fiona Reid ([email protected]), Eurosurveillance editorial office.
EuroHIV publishes latest data on HIV/AIDS surveillance in Europe
The European Centre for the Epidemiological Monitoring of AIDS (EuroHIV programme –
http://www.eurohiv.org/) has published its latest half-yearly surveillance report (1). The report contains
information on cases of AIDS and newly diagnosed HIV infections reported by 30 June 2001 in the 51
countries of the World Health Organization’s European Region, together with data on HIV prevalence among
injecting drug users (IDUs) in 20 countries for 1996-2000. For the purposes of this report, the 51 countries
have been grouped into three areas – the West, the Centre, and the East – and most data are presented and
discussed in this context.
Findings
Both the incidence of AIDS and the annual number of reported deaths from AIDS have been decreasing
since highly active antiretroviral treatment (HAART) was introduced in 1996. In homo- and bisexual men and
in IDUs the decrease in AIDS cases has continued, albeit at a slower rate. These trends seem to be
continuing in 2001. For the first time in 2000 and again in 2001, the number of cases diagnosed in
heterosexually infected people was the same as in IDUs.
In the Centre, the incidence of AIDS is below 6 cases per million population in any year, and newly diagnosed
HIV infections are also low, at 7-10 per million. The region accounts for the largest proportion of infection in
children, however, after an outbreak among young children in Romania around 1990.
In the East, the epidemic is continuing to spread to an ever increasing number of countries in the region.
Newly diagnosed HIV infections were reported at 242 per million population, and the ratio of male to female
cases is 3.2:1. Over 60% of cases are reported among IDUs and some 30% with an unknown mode of
transmission, but most of these would have occurred among IDUs. The annual reporting rate of newly
diagnosed HIV infections has greatly increased since 1995 in Ukraine, Russia, and Latvia, and, since 1999,
in Estonia. Azerbaijan, Kazakhstan, and Kyrgyzstan reported more cases in the first six months of 2001 than
for the whole of 2000. In contrast to the increase in HIV diagnosis, the reported incidence of AIDS has
remained low in the region, at less than 3 per million, but has increased in Ukraine (12.9 per million) and
Latvia (9.8 per million).
In the West, the situation is endemic; heterosexual transmission accounts for an increasing proportion of HIV
infections. IDUs and homo- and bisexual men, however, remain the populations most at risk.
Conclusions
The main challenges are to avoid relapses to high risk behaviours and to provide access to testing and care
to all HIV infected people, particularly migrants from countries with generalised epidemics. The challenge for
the Centre lies in sustaining the success in avoiding large scale epidemics. The East needs to control its
epidemic among IDUs, to monitor the extent to which HIV is currently spreading through heterosexual and
homosexual contact, and to prevent large scale sexual transmission.
Reference:
1.
European Centre for the Epidemiological Monitoring of AIDS. HIV/AIDS surveillance in Europe. Mid-year report 2001, no.65. St
Maurice: EuroHIV, 2002. (http://www.eurohiv.org/AidsSurv/rapport_65/rap_eurohiv65.pdf)
Reported by Birte Twisselmann ([email protected]), Eurosurveillance editorial office.