Eurosurveillance - Volume 15, Issue 17, 29 April 2010

On 23 April 2010, the World Health Organisation announced the confirmation of wild poliovirus serotype 1 (WPV1) in seven samples from children with Acute Flaccid Paralysis in Tajikistan, in the context of a multi-district cluster starting in December 2009. As of 28 April, 32 of 171 reported cases were laboratory-confirmed and most closely related to virus from Uttar Pradesh, India. This outbreak demonstrates the high risk that still exists for importation of wild poliovirus into polio-free regions.

The reappearance of circulating wild poliovirus type 1 (WPV 1) in Tajikistan is the first outbreak from imported wild poliovirus since the World Health Organization (WHO) European Region was declared polio-free in 2002. The risk of poliomyelitis importation to the European Union and European Economic Area countries has probably not increased, but the current outbreak is a reminder that high vaccination coverage, monitoring of protective immunity and maintaining surveillance are important to sustain the present polio-free situation.

Since December 2009, mumps incidence has increased in the Netherlands. As of 20 April 2010, 172 cases have been notified on the basis of laboratory confirmation or linkage to a laboratory-confirmed case. Of these, 112 were students, the majority of whom had been vaccinated (81%). Although outbreaks in vaccinated populations have been described before, risk factors for exposure and susceptibility, and dose-dependent vaccine effectiveness in a student population of this nature are relatively unknown.

We describe a local indigenous outbreak of measles in a susceptible Roma community, which occurred in Pulawy, a town of 50,000 citizens in the Lubelskie province (eastern Poland) during summer 2009. From 22 June to 30 August 2009, 32 measles cases were reported, and additionally nine possible cases were actively identified. A mass immunisation campaign was organised to stop measles transmission in the Roma community. Active surveillance of rash-febrile illnesses allowed documentation of the impact of mass immunisation in preventing further measles spread in the Roma community, and the surrounding population of Pulawy.

The objective of this study was to describe transmission chains of measles observed in Poland during 2008-2009. A decade ago, the incidence of measles in Poland declined and approached one case per million inhabitants one of the World Health Organization's criteria for measles elimination. Following a period of very few reported measles cases (2003 to 2005), an increase in incidence was observed in 2006. Since then, the incidence has constantly exceeded one case per million inhabitants. Of 214 measles cases reported in 2008 and 2009 in Poland, 164 (77%) were linked to 19 distinct outbreaks, with 79% of cases belonging to the Roma ethnic group. Outbreaks in the non-Roma Polish population had different dynamics compared to those in the Roma population. On average, measles outbreaks in Roma communities involved 10 individuals, seven of whom were unvaccinated, while outbreaks in the non-Roma Polish population involved five individuals, half of whom were incompletely vaccinated. The majority of outbreaks in Roma communities were related to importation of virus from the United Kingdom. In six outbreaks, the epidemiologic investigation was confirmed by identification of genotype D4 closely related to measles viruses detected in the United Kingdom and Germany. Our data indicate that Poland is approaching measles elimination, but measles virus circulation is still sustained in a vulnerable population. More efforts are needed to integrate the Roma ethnic group into the Polish healthcare system and innovative measures to reach vulnerable groups should be explored.

During a mass immunisation campaign following an outbreak of measles in a Roma community settled in the town of Pulawy, Poland, we performed an estimation of the size of this Roma population and an assessment of its vaccination uptake. We obtained a list of Roma residing in Pulawy from the local municipality and estimated using a simple capture-recapture formula that Pulawy had 377 Roma residents (43% under 20 years old), which was 27% more than the 295 registered at the municipality. During the vaccination campaign, demographic information was recorded that could be linked to information from the municipality list as well as to prior immunisation status. Among the people whose data were recorded during the vaccination campaign, 14% were not registered at the primary healthcare centres, and were therefore deprived of access to healthcare. Among 102 screened subjects under the age of 20 years, 51% were vaccinated according to schedule. Vaccine uptake for the first dose of measles-containing vaccine was 56% (54/96) and for the second dose 37% (18/49). The present study indicates the need to get a better demographic overview of Roma communities living in Poland and to understand the barriers limiting their access to healthcare and social services. Organisation of catch-up immunisations of this vulnerable population is necessary.

To ascertain measles-mumps-rubella (MMR) immunisation coverage among school leavers in an inner city London borough following a local MMR catch-up initiative, a questionnaire was sent to parents and guardians of adolescents who attended the 12 secondary schools in Haringey and were due for the school leavers' vaccination. The questionnaire enquired about previous history of MMR vaccination and a history of adverse events or contraindications to the vaccine. The electronic immunisation records of 400 children (30-35 students from each school) included in the catch up initiative were randomly selected. The childrens' school health records were manually compared with the electronic records. The mean age of the children was 14.7 years, and 224 (56%) were male. Of the 373 records examined prior to the local MMR catch-up initiative, 98 children (26%) had never received MMR, 173 (46.5%) had only had one dose, 100 (27%) had two doses, and two children had three doses of the vaccine. During the school leavers' MMR immunisation, 171 (43%) received a dose of MMR and the number of children immunised with two doses increased to 206 (55.3% versus 27% P<0.001), doubling the coverage. Offering MMR vaccination as part of the school leavers' immunisation is logistically convenient and it may limit the extent of outbreaks. .