Eurosurveillance

ECDC

Abstracts from the Regional Epidemiologists' meeting, Kristiansand 2010

 Rediger
  Published: 17.02.11 Updated: 17.02.2011 16:34:09

Results of the First Wave of the (H1N1) 2009 Infl uenza Pandemic in Murmansk Oblast

E.A. Matsievskaya

Directorate of the Federal Service for Surveillance on Consumer Rights Protection and Human Well-Being in Murmansk Oblast

Citation: Matsievskaya E.A. Results of the First Wave of the (H1N1)2009 Influenza Pandemic in Murmansk Oblast. EpiNorth 2010; 11: 94-6.

After WHO announced the emergence of a new pandemic influenza virus and reported the beginning of phase 5 of the pandemic, active response measures were taken in the Murmansk oblast. The preparatory measures were goal-oriented because WHO had already collected information concerning the clinical picture, epidemic-specifics of the disease and about control measures taken in countries that had been affected by the pandemic. During the first stage that lasted from April 30 to the middle of October, measures were taken to prevent the import and spread of highly pathogenic influenza in the territory of Russia.

The activities of all services were planned to prepare for the first wave of the pandemic. Before the epidemic growth started, 8 sessions of the committee on influenza spread prevention were held. The resolutions of the committee were taken in response to the current epidemic situation.

  • Antiviral medicines were secured in hospitals and in pharmacies available for the general public. Twelve mechanical ventilators were purchased to serve 0.44% of the estimated number of patients. A plan for optimizing the existing capacity of hospitals was designed and special training was organized for medical workers including epidemiologists and virologists.
  • 44,236,600 rubles were allocated for the implementation of preventive and counter-epidemic measures. The funds were taken from the Murmansk oblast budget, the federal budget, from the reserve funds for preventive activities of insurance organizations in healthcare (13,630,000 rubles).
  • Using funds (6.5 million rubles) from the Murmansk oblast budget, various medicines, disinfectants, protective clothing and utilities for medical workers were purchased by State Healthcare Institution “Murmansk Territorial Centre for Medicine of Catastrophes” in order to create a stockpile for treatment of severe cases of influenza.
  • The Directorate of Rospotrebnadzor purchased “non-contact” devices for measuring body temperature at the sanitary quarantine stations (SQS) and consumables for rapid PCR diagnostics. An additional training course at the Influenza Research Institute was held for a virologist.
  • Virological monitoring was organized at the virological laboratory at the Federal State Healthcare Institution “Centre of Hygiene and Epidemiology in Murmansk Oblast”.
  • In August and September, clinical samples from patients suspected of being infected with (H1N1) 2009 influenza were delivered to the reference center for monitoring infections of the higher and lower respiratory tract at the Federal State Science Institution “Central Research Institute of Epidemiology of Rospotrebnadzor”.
  • On November 12, 2009 diagnostic laboratory investigations (PCR) of specimens for pandemic influenza started in the regional clinical hospital. The specimens were obtained from patients suffering from severe or atypical influenza, or from patients belonging to risk groups.
  • During the epidemic period, 731 people were tested for influenza by PCR at the virological laboratory of the “Centre of Hygiene and Epidemiology in Murmansk Oblast”; 279 samples yielded positive results (38.5%). Samples from 513 people were subjected to the hemagglutination inhibition consumption test, 175 samples yielded positive results (34%). From November 12, 2009, 367 patients were examined by PCR at the regional clinical hospital, 79 had positive results (21.6%).
  • In Murmansk oblast there are 6 special checkpoints located on the state border of the Russian Federation. Three of the six checkpoints (the seaports of Murmansk and Kandalaksha and the airport in Murmansk) have SQS equipped with non-contact infrared thermometers. From May 1, 2009 to June 20, 2010, 293 international flights arrived at the Murmansk airport carrying a total of 8,224 passengers. 1,321 Russian ships and 594 foreign ships came to the Murmansk seaport with 27,146 and 11,949 crew aboard, respectively. In addition, 6 cruise ships (9,890 people aboard) came to Murmansk. Forty seven foreign ships with 552 people aboard arrived at the port of Kandalaksha. No passengers or crew were suspected of being infected with influenza.
  • Up to 600 people cross the Russian Federation border daily via car checkpoints (CCPs): Via CCP “Borisoglebsky” as many as 150 vehicles and 250-350 people pass the state border every day, including up to 50 crew members of fishing ships with bases located in Norway. Via CCP “Lotta” 20-30 cars and 60-100 people pass everyday and via CCP “Sala” 30-50 cars and 100-130 people.
  • In August 2009, near CCP “Borisoglebsky” in the Sør-Varanger county, Norway, an outbreak of (H1N1) 2009 pandemic influenza (38 cases) occurred in the military community in the city of Kirkenes. The outbreak was confi rmed by the Foreign Ministry Representative Office of the Russian Federation and the Norwegian Institute of Public Health. According to official data, 1 case of influenza was registered among the local population in the county.
  • In response to the outbreak in the Sør-Varanger county, preventive measures were designed and implemented at CCP “Borisoglebsky” on a temporary basis. For two weeks starting from August 17, all people coming to this border checkpoint were examined using the non-contact thermometer to detect persons with acute respiratory viral infections (ARVI). People were informed about the necessity of taking preventive measures and were given instruction leaflets.

 

Counter-Measures Against Pandemic Influenza in the Russian Federation

N.V. Frolova

Federal Service for Surveillance on Consumer Rights Protection and Human Well-Being, Russia

Citation: N.V. Frolova Counter-measures against Pandemic Influenza in the Russian Federation. EpiNorth 2010; 11:97-8.

Following the official announcement from the Ministries of Health in USA and Mexico about influenza cases caused by the new А(H1N1)pdm virus, planning and implementation of preventive and counter-epidemic measures were started in the Russian Federation. Targeted financial support was provided. The activities were controlled by the Committee of the Government of the Russian Federation for coordination of measures against import and spread of the diseases caused by the highly pathogenic influenza virus in the territory of the Russian Federation. All regions in the country received information regularly about the global situation regarding highly pathogenic influenza and about counter-epidemic and preventive activities conducted in Russia and abroad.

In the spring and summer of 2009, health screening of persons coming from affected countries was performed. All people with symptoms arriving from countries in which highly pathogenic influenza had been detected were hospitalized and laboratory analyses were conducted. In addition, all contacts were traced and subject to medical monitoring. Children coming from other countries before the beginning of the school year were monitored by healthcare workers and were not admitted to school during the monitoring period.

The first summer wave of pandemic influenza was observed in many European countries but was not registered in Russia. During this period, measures were taken to secure a stockpile of antiviral medicines and individual protective respiratory devices, and to supplement the existing mechanical ventilators. Plans for optimizing the existing capacity of healthcare institutions were designed and training courses for medical personnel were organized.

Measures were taken to perform laboratory diagnostics for the (H1N1) 2009 influenza in the regions of the country. New reagent kits for identifying the А(H1N1)pdm influenza virus were designed and production was started. In addition, work was organized to obtain virus isolates in specimens taken from diagnosed patients in order to develop vaccines against the pandemic influenza.

On September 1, 2009 weekly monitoring of the viruses circulating as well as registration of influenza and acute respiratory viral infections (ARVI) cases were introduced. The seasonal growth of ARVI morbidity started in September 2009. In the etiological structure of the diseases, non-influenza viruses prevailed. The proportion of (H1N1) 2009 influenza gradually increased. The peak of influenza and ARVI morbidity was recorded in November 2009. By that time, the proportion of А(H1N1)pdm virus among screened patients had reached 30.4%. Other respiratory viruses (1.8-2.8%) continued to circulate simultaneously.

In the first ten days of January 2010 (New Year holidays and winter vacations for school children in the country), the incidence of influenza and ARVI was quite low. The proportion of А(H1N1)pdm influenza in the structure of circulating respiratory viruses started to decrease. From February to April 2010 the proportion of influenza virus А(H1N1)pdm constituted approximately 1%, which corresponded to the proportion of other circulating influenza viruses (0.5%-2.0%).

On average, the epidemic season in the Russian Federation lasted from 7 to 9 weeks. In Russia, 13.26 million people were infected with influenza and ARVI during the epidemic in October-December 2009 which was 5.82 million more than during the same period in 2008.

The following activities were conducted in the Russian Federation to reduce morbidity of ARVI and influenza (including pandemic influenza):

  • In 2009 the population was immunized against seasonal influenza. The immunization of 27 million people belonging to risk groups was financed by the federal budget and 7.3 million people were immunized using other sources of financing.
  • Teaching in educational institutions was suspended when epidemic growth of the disease incidence was observed.
  • Cultural and sports events were cancelled.
  • Anti-epidemic measures were taken in public locations, institutions for children, and medical and preventive treatment facilities.
  • In December 2009, immunization with the pandemic influenza vaccine was started among people belonging to risk groups. Over 25 million people were vaccinated.

 

 

Situation Update in the European Region: Overview of Influenza Surveillance Data Week 40/2009 to Week 07/2010

J. A. Mott

WHO Regional Office for Europe

Citation: Mott JA. Situation update in the European Region: overview of influenza surveillance data week 40/2009 to week 07/2010. EpiNorth 2010; 11:99-100.

Background

WHO/Europe publishes a weekly electronic bulletin on influenza activity in the Region and performs periodic analysis of EuroFlu surveillance data provided by the 53 WHO European Member States.

Methods

We analysed current and historical trends in outpatient and influenza surveillance data, performed a correlational analysis to assess the geographic progression of peak clinical activity during the pandemic winter wave, reviewed data on severe influenza cases reported into EuroFlu, and analysed antigenic and genetic characteristics of viruses collected from the national surveillance systems.

Results

A preliminary review of data submitted to EuroFlu between week 40/2009 and week 07/2010 was compared with available historical data. Results suggest that countries in the European Region experienced an early start to the influenza season, and that clinical activity during the winter season also peaked earlier than in several years. The winter pandemic (H1N1) 2009 wave was generally of similar length when compared with previous seasons. In 19 of 22 countries reporting five or more years of data, the peak clinical consultation rates that were observed during the 2009/2010 pandemic season did not exceed peak clinical consultation rates observed during the previous years. However, in several countries, clinical consultation rates for some younger age groups exceeded recent historical peaks. Within the western part of the Region, the geographic progression of the pandemic occurred in a west to east direction. The pattern of influenza spread became less well-defined in countries east of longitude 50E. A total of 4,572 laboratory-confirmed deaths associated with pandemic (H1N1) 2009 were reported to WHO/Europe during the pandemic. Although this figure provides an underestimate of the actual number of deaths associated with pandemic virus A(H1N1)pdm infections, crude estimates of mortality suggest similar rates to those observed in countries during the winter season in the southern hemisphere. Clusters of deaths and severe cases that were investigated suggest that delayed time to treatment was an important risk factor for death. The vast majority of influenza virus detections were pandemic influenza A (H1N1)pdm. All pandemic A (H1N1)pdm viruses analysed antigenically or genetically (N = 995) were similar to the vaccine strain and the majority were sensitive to both oseltamivir and zanamivir.

As of week 7/2010, 40 Member States in the European Region administered a total of approximately 58.2 million doses of vaccine. According to currently available data, uptake rates varied considerably between countries, ranging from approximately 4%-70%. Adverse event monitoring activities have shown no serious adverse events associated with any licensed vaccine. Public concerns on safety issues have focused mainly on adjuvant vaccines, but to date no scientific evidence exists to substantiate these concerns.

Conclusions

The extent to which circulating influenza A viruses remain antigenically similar to the A/California/7/2009 (H1N1) virus may influence the relative circulation of influenza A (H1N1) and influenza A (H3N2) during the next winter season and will also influence the anticipated burden of influenza in the European population. The future burden of the A(H1N1)pdm virus on populations over age 60 that are believed to have a degree of immunity to the currently circulating virus may be influenced by any antigenic drift that occurs. WHO/Europe is grateful for the enormous effort put forth by the Member States to maintain and strengthen influenza surveillance during this pandemic season.

 

 

Epidemiological Situation of Pandemic (H1N1) 2009 Influenza in Lithuania

G. Amasenkovaitė

Centre for Communicable Diseases and AIDS

Citation: Amasenkovaitė G. Epidemiological situation of pandemic (H1N1) 2009 influenza in Lithuania. EpiNorth 2010; 11: 101.

Response to the emergence of new influenza virus resulted in several changes in the influenza surveillance system in Lithuania. Enhanced influenza surveillance was established and infection control was strengthened.

The last influenza season (2009-2010) in Lithuania was unusual as it was throughout Europe. The season was characterized by a more intense influenza activity and an earlier epidemic peak with an incidence rate twice as high as during the two previous seasons. In 2007-2008 and 2008–2009 the influenza morbidity peak was observed in January–March while in 2009-2010 the peak was in November - December.

On 26 June 2009, Lithuania reported the first laboratory-confirmed case of pandemic influenza (H1N1) 2009. By March 2010, 810 laboratory-confirmed cases, including 23 fatal cases, had been reported. The highest proportion of cases was among the age group of 20-29 years and women were more affected than men. The clinical picture and severity of disease in Lithuania was similar to that reported by other countries.

 

 

Response in Norway to the 2009 Influenza Pandemic

P. Aavitsland

Norwegian Institute of Public Health

Citation: Aavitsland P. Response in Norway to the 2009 influenza pandemic. EpiNorth 2010; 11: 102 3.

Before the pandemic started, Norway had a national pandemic preparedness plan from 2006. A revised version was almost ready for publication, just waiting for the new WHO global plan. The revision was partly based on a 2008 review by the European Centre for Disease Prevention and Control (ECDC) of Norwegian pandemic preparedness. Preparedness included securing 1.4 million courses of oseltamivir and an advance purchase agreement for pandemic vaccines.

Two parallel strategies were followed in the response to the pandemic in Norway:

The ”delay and reduce” strategy targeted the entire population. The purpose was to use commensurate measures (measures relevant to the level of the threat) to delay the spread, but not at any cost. The purpose was not to contain the spread, which was deemed impossible from the outset. The strategy included hand hygiene, couch etiquette, home isolation of influenza patients for seven days and an offer for vaccination to everyone. Other measures were deemed inappropriate for this mild disease: social distancing measures such as school closures and cancelling of events, wearing masks in public, contact tracing and antiviral prophylaxis, and screening at the borders.

The ”protect” strategy targeted mainly individuals belonging to risk groups, i.e. the groups most likely to develop severe influenza. The purpose was to prevent complications and deaths. The strategy included information on who belonged to risk groups and their need for early treatment, the provision of oseltamivir to persons at risk early in infection, postexposure prophylaxis to persons at risk, prioritised vaccination of risk groups, and increased training and equipment in hospitals to treat severe cases.

The vaccination campaign started in week 42 (the third week in October). ”Pandemrix” from GlaxoSmithKline was administered. The order of vaccination was: pregnant women, medical risk groups, healthcare personnel, children, and the rest of the population. Each person received one dose. Approximately 45% of the population was vaccinated and around 90% of these were registered by personal identification number in the national vaccination registry.

Communication to the public was in collaboration between the Norwegian Institute of Public Health and the Directorate of Health (the Chief Medical Officer). One web site was devoted to the public, another to health professionals.

There were several press conferences that were led by the Chief Medical Officer and the Deputy State Epidemiologist. The latter was also available around the clock during the pandemic. There were several communication challenges, including explanations of risk assessment and strategy, questions about vaccine safety and conspiracy theories.

Among the Norwegian population of 4.8 million we estimate that there were approximately 900,000 people infected during the pandemic. We registered approximately 13,000 laboratory confirmed cases, around 1,300 hospital admissions and about 180 admissions to intensive care units. Interestingly, there are almost no confirmed cases among people older than 70 years of age. Twenty nine deaths from pandemic influenza were registered.

 

 

Epidemic Situation of Pandemic Influenza in Ukraine: Preventive and Counter-Epidemic Activities

L.M. Mukharska

Department for Organization of Sanitary and Epidemiological Surveillance of the Ministry of Health, Ukrain

Citation: Mukharska L.M. Epidemic Situation of Pandemic Infl uenza in Ukraine: Preventive and Counter-Epidemic Activities. EpiNorth 2010; 11:104-6.

Following announcements from the Health Ministries in the US and Mexico about the new А(H1N1)pdm influenza virus, the government of Ukraine adopted several decisions in accordance with WHO recommendations. The decisions regulated the organization and financing of the activities to prevent the spread of swine influenza in the territory of the country.

The epidemic situation was aggravated by simultaneous circulation of pandemic influenza and other influenza virus strains. The 2009-2010 influenza pandemic in Ukraine developed after several years of relative epidemiological well-being. Since 1993 the incidence of influenza and acute respiratory viral infections (ARVI) decreased gradually and the incidence rates were no more than 15-20 thousand cases per 100,000 population. Prior to 1992 incidence rates reached at least 25-30 thousand cases per 100,000 population.

The epidemic growth of influenza in November-December 2009 was considerably different from previous years. The new pathogen spread rapidly all over the world and dominated over other influenza viruses. The epidemic growth of disease started earlier than usual, during week 42-44, while seasonal influenza typically started in weeks 4-8. In addition, the antigenic characteristics of the new pandemic pathogen differed greatly from the seasonal influenza viruses of the last few decades. Consequently, the disease affected a wider range of the young adult non-immune population. The maximum incidence was registered among people under the age of 50, though usually the seasonal influenza mostly affected children. The further spread of the pandemic infection will inevitably effect the entire population. The secondary attack rate of the new pandemic influenza is currently estimated at 22-33% while the secondary attack rate of seasonal influenza varies from 5 to 15%.

In November 2009 influenza cases were registered in all parts of Ukraine. The incidence peak was reached in weeks 45-51 when the threshold incidence was exceeded in almost every region of the country. During the epidemic period from October 29, 2009 to April 4, 2010, a total of 6,496,175 people (14.14% of the population) were infected with influenza and ARVI with complications (such as pneumonia, etc.). Hospitalization was necessary for 371,512 patients (5.72% of the infected population) and 1,128 deaths associated with influenza- and ARVI related complications were registered (0.02% of the infected population and 0.3% of all hospitalized patients). Laboratory analyses by PCR were performed on samples obtained from 0.2% of the infected population. A total of 65,514 medical workers (1% of the infected population) were infected with influenza or ARVI and complications such as pneumonia. Hospitalization was required for 5,194 medical workers and 38 medical workers died (7.9% and 0.06% of the infected population, respectively).

Based on current reports received from the regions in Ukraine it was possible to analyze the influenza transmission dynamics in the territory of the country. There was a five-week interval between the first incidence peak when the epidemic growth started (week 45) and the second peak (week 51) during which the disease spread from the western region to the central, eastern and southern parts of the country. The average duration of the epidemiological threat in the regions of Ukraine varied from 7 to 9 weeks.

The duration and intensity of the influenza epidemic in the country was influenced by the decisions of emergency counter-epidemic committees. Based on an initiative from the state sanitary and epidemiological service social restrictions were imposed on October 29, 2009. Teaching at schools and institutions of higher education was suspended, kindergartens were closed, the use of masks in public locations was recommended, etc.

By April 30, 2010 virological laboratories had received 22,917 samples from patients with influenza and ARVI; 15,565 (67.9%) of the samples were tested by PCR. Influenza A was detected in 38% of the samples and the share of the new (Н1N1) 2009 pandemic influenza was as high as 93%. Influenza В was detected in 0.4% of the samples. Among 1,414 samples collected from deceased patients, 884 (62.5%) were positive for the new pandemic А(Н1N1) pdm influenza virus. Consequently, the prevailing pathogen causing the influenza epidemic in Ukraine during the 2009-2010 season was the new pandemic А(Н1N1)pdm virus.

Having analyzed the number of hospitalizations among adults and children in ten control cities in Ukraine during the 2007-2008 and 2008-2009 seasons, it is possible to conclude that the number of hospitalizations remained stable and reached a maximum of 299-407 cases in different years. However, during the 2009-2010 season, a rapid increase of 79.4% in number of hospitalizations was registered from week 44 to 45 in 2009. This increase was 11.7 times higher than in week 45 of the previous season.

The peak of hospitalizations was observed in weeks 45 and 52. The growth rate of 93.7% was registered in week 52 and was 10 times higher than in week 52 of 2008. This growth rate was not typical of the 2007-2008 and 2008-2009, and could be caused by the increase in disease incidence as well as the greater concern among the population and medical workers.

During the first few weeks of the epidemic (until November 4, 2009) in Ukraine 4.6% of all patients with influenza-like diseases were hospitalized. During this period, each day up to 20% more influenza and ARVI cases were registered than the previous day. Of patients seeking medical attention 3-8% needed hospitalization, 3-9% of hospitalized patients underwent resuscitation and 0.5-1.2% of hospitalized  patients received mechanical ventilators. The case fatality rate was 0.01% among infected people. This epidemic included more cases of the severe form of disease with a higher probability of lethal outcome for patients with cardiovascular pathologies, insular diabetes, overweight (more than 20%) and for pregnant women.

Only 6.95% of the total number of people scheduled for vaccination (3,439,932 people) were vaccinated and registered in medical facilities. Such an insignificant proportion of vaccinated persons in the population will only provide personal immunity and does not create herd immunity that might help to control the circulation of the influenza pathogen in an epidemic season.

The following activities were conducted in Ukraine in response to the pandemic (H1N1) 2009 influenza:

  • the Ministry of Health of Ukraine established an emergency response centre to control the spread of influenza and ARVI in the country.
  • Emergency counter-epidemic committees were established in all regions of the country. The sessions of the committees were devoted to the analysis and approval of regional plans for measures to prevent the spread of the (H1N1) 2009 influenza among the population.
  • A three-level system of epidemiological surveillance was implemented in Ukraine to monitor the incidence of influenza and ARVI.
  • The virological laboratories of the State Sanitary Epidemiological Service were completely equipped with all necessary materials and tools. The Ukrainian centre of influenza and acute respiratory infections at the Ministry of Health was also supplied with the required equipment and test systems.
  • Approaches to the provision of healthcare and organization of response activities were modified to improve the quality of healthcare services in accordance with suggestions from WHO and specialists from the Ministry of Health. A healthcare algorithm for patients with pandemic influenza caused by the А (H1N1)pdm virus was introduced as well as a clinical protocol for diagnostics and treatment of children suffering from the pandemic influenza caused by the А (H1N1)pdm virus.
  • Counter-epidemic activities were intensified. A comprehensive range of disinfection measures were introduced in all administrative areas in public facilities (including airports, railway stations, bus stations, sea ports and river ports), pre-school institutions, cultural and educational institutions, at various enterprises, institutions, organizations and medical facilities regardless of forms of ownership.
  • Sanitary and counter-epidemic activities at checkpoints on the state border were established.
  • Sanitary education among the population was conducted. People were provided with instructions regarding individual protection and how to prevent infections of the pandemic influenza and ARVI.

 

Danish Experience With Infl uenza (H1N1) 2009 Pandemic

K.Mølbak1, K.Widgren1,2, K.Skovbo Jensen3, S.Ethelberg1, A.H. Christiansen1, H.-D.Emborg1, S.Gubbels1, K. Majlund Harder1, T.Grove Krause1, A. Mazick1, L.P.Nielsen4, J.Nielsen1, P. Valentiner-Branth1, S.Glismann1

1 Department of Epidemiology, Statens Serum Institut, Copenhagen, Denmark

2 European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC) Stockholm, Sweden

3 Department of Microbiological Surveillance and Research, Statens Serum Institut, Copenhagen, Denmark

4 Department of Virology, Statens Serum Institut, Copenhagen, Denmark

Citation: Mølbak K, Widgren K, Jensen KS et al. Danish experience with infl uenza (H1N1) 2009 pandemic. EpiNorth 2010; 11:107-8.

The disease burden due to the 2009 influenza (H1N1) 2009 pandemic remains poorly described. Danish surveillance data to estimate influenza associated morbidity and mortality in 2009 was analysed. To obtain population-based figures on the number of illnesses, we combined and modelled data from two different primary healthcare surveillance systems, national numbers of samples tested positive out of all samples received for influenza analysis, and data on healthcare- seeking behaviour during the pandemic. In addition, we obtained data on influenza-related hospital admissions. Mortality was estimated among laboratory-confirmed cases and also expressed as excess all-cause mortality over a modeled baseline of weekly number of expected deaths.

In total, 270,000 individuals (5%) of the population experienced clinical illness; this estimate varied by age and was highest among children 5-14 years (15%). Compared with the expected number of hospital admissions, there was a 72% increase in number of influenza-related hospital admissions. However, the number of patients admitted to intensive care did not exceed 5% of the national capacity. Estimates of the number of deaths ranged from 30 to 227 (0.5 to 4.1 per 100,000 population) depending on the methodology.

In conclusion, the pandemic was characterised by high morbidity affecting mainly children and young adults, and unprecedented high rates of admissions to hospitals for a range of influenza-related conditions coinciding with the peak of the pandemic. Nonetheless, the burden of illness was lower than predicted in planning scenarios, and suggests that the present pandemic may indicate a favourable genetic shift in influenza A virus.

 

Surveillance and Control of Pandemic Influenza (H1N1) 2009 in Latvia During 2009/2010

J. Perevoscikovs, R. Nikiforova

Department of Epidemiological Surveillance of Infectious Diseases and Immunization, State Agency “Latvian Infectology Centre”

Citation: Perevoscikovs J, Nikiforova R. Surveillance and control of pandemic infl uenza (H1N1) 2009 in Latvia during 2009/2010. EpiNorth 2010; 11:109-10.

Surveillance, monitoring and control of influenza is performed during the period from the week 40 of the previous year until the week 20 of the current year and could be extended in case WHO has announced the pandemic phase 4 to 6. In the 2009/2010 season 60 primary healthcare physicians, 11 hospitals, 43 schools and 35 kindergartens provided influenza monitoring data. A population coverage of 4.8% was achieved. The healthcare practitioners involved in the monitoring of influenza provided data regarding the cases of influenza-like illness (ILI), acute respiratory infections (ARI) and pneumonia by completing and sending a special form to regional epidemiologists at the Latvian Infectology Centre (LIC) once a week. Healthcare practitioners collected and delivered clinical specimens to the reference laboratory at LIC in the following cases:

  • Professionally substantiated suspicions regarding a cluster of influenza-like illness in the period of time between epidemics;
  • ARI with complications in a patient admitted to hospital;
  • Influenza with complications in a person vaccinated against influenza with the vaccine recommended by WHO for a particular epidemiological season;
  • Death of a patient with ARI symptoms;
  • Person with ARI symptoms during a pandemic threat who has visited a country or territory affected by possible pandemic virus or has been in contact with a person possibly infected with a pandemic strain.

A rapid increase of epidemic activity was observed from week 46/2009 and reached a maximum in week 48/2009 (ILI rate 527, 2 per 100,000 population). All isolates (100%) during the epidemic were influenza A(H1N1)pdm pandemic strains. All viruses were A/California/7/2009(H1N1)v based on antigenic characterization. From week 11/2010 influenza B virus of the B/Yamagata lineage was detected.

Altogether 35 deaths associated with laboratory-confirmed pandemic (H1N1) 2009 were reported from week 46/2009 to week 05/2010. The majority (69%) were registered from week 48/2009 to week 51/2009. Twenty two (63%) of the deaths were among patients with underlying medical conditions and 2 (6%) were pregnant women.

The pandemic preparedness and response plan was in place. The state medical emergency committee had several meetings before and during the pandemic wave. The decision to monitor influenza death cases was taken for the first time.

Influenza surveillance data were published weekly and were available on the LIC website (http://www.lic.gov.lv/?p=7800&lang=258). All relevant information on influenza prevention for professionals and the public was also available on this website.

School closure was not a common practice during the epidemic. No pandemic vaccine was available in Latvia. The capacity of hospitals and ICU was sufficient. Communication with mass media was conducted on the regular basis.

 

Vaccination Against Pandemic Influenza in Norway During 2009

S. Sandbu

Department of Vaccines, Norwegian Institute of Public Health, Oslo

Citation: Sandbu S. Vaccination against pandemic influenza in Norway during 2009. EpiNorth 2010; 11: 111.

Preparation for pandemic influenza vaccination had been going on for several years prior to 2009. A delivery agreement with the vaccine producer Solvay was developed and seven regional conferences addressing the organization of pandemic vaccination were held. After a new tender invitation in 2008, a delivery agreement was prepared with the vaccine producer GlaxoSmithKline (GSK), securing 3.13% of their production capacity of pandemic influenza vaccine.

GSK was the first to produce an immunogenic and safe pandemic influenza vaccine. It was based on a well-documented model vaccine. Clinical trials in adults as well as other investigations were performed before the vaccine was approved by the Norwegian Medicines Agency at end of September 2009. The vaccine Pandemrix was prepared with a new adjuvant and contains thiomersal preservative.

Limited amounts of vaccine arrived each week and were distributed to all municipalities. During October – December 2009 approximately 2 million persons were vaccinated. Most of the vaccinations were entered into the national vaccination register. Vaccine adverse events were recorded in the existing notification system. 


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