Stefania Iannazzo

Epidemiology of pertussis in italy: Disease trends over the last century

We reviewed the epidemiology of pertussis in Italy over the last 125 years to identify disease trends and factors that could have influenced these trends. We described mortality rates (1888-2012), case fatality rates (1925-2012), cumulative incidence rates (1925-2013) and age-specific incidence rates (1974-2013). We compared data from routine surveillance with data from a paediatric sentinel surveillance system to estimate under-notification. Pertussis mortality decreased from 42.5 per 100,000 population in 1890 to no reported pertussis-related death after 2002. Incidence decreased from 86.3 per 100,000 in 1927 to 1 per 100,000 after 2008. Vaccine coverage increased from 32.8% in 1993 to about 96% after 2006. As for under-notification, mean sentinel/routine surveillance incidence ratio increased with age (from 1.8 in <1 year-olds to 12.9 in 10-14 year-olds). Pertussis mortality decreased before the introduction of immunisation. Incidence has decreased only after the introduction of pertussis vaccine and in particular after the achievement of a high immunisation coverage with acellular vaccines. Routine surveillance does not show an increase in cumulative incidence nor in ≥ 15 year-olds as reported by other countries. Underrecognition because of atypical presentation and the infrequent use of laboratory tests may be responsible for under-notification, and therefore affect incidence reports and management of immunisation programmes.

Increased incidence of invasive meningococcal disease of serogroup C / clonal complex 11, Tuscany, Italy, 2015 to 2016.

We report an increase of serogroup C Neisseria meningitidis invasive meningococcal disease in Tuscany. From January 2015 to end February 2016, 43 cases were reported, among which 10 were fatal, compared to two cases caused by serogroup C recorded in 2014 and three in 2013. No secondary cases occurred. Thirty-five strains belonged to C:P1.5-1,10-8:F3-6:ST-11(cc11). Control measures have been adopted and immunisation campaigns implemented. Studies on risk factors and carriage are ongoing.

A large prolonged outbreak of hepatitis A associated with consumption of frozen berries, Italy, 2013-14.

Purpose. In 2013/2014, Italy experienced one of the largest community‐wide prolonged outbreaks of hepatitis A virus (HAV) throughout the country. The article provides a comprehensive description of the outbreak and the investigation carried out by a multidisciplinary National Task Force, in collaboration with regional and local public health authorities. Control strategies of food‐borne HAV infection in both the human and food sectors are also described. Methodology. Enhanced human epidemiological and microbiological surveillance together with microbiological monitoring of HAV in food and trace‐back investigation were conducted. Results. A total of 1803 HAV cases were identified from 1 January 2013 to 31 August 2014, in Italy. Sequencing was possible for 368 cases (20.4%), mostly collected between 1 January 2013 and 28 February 2014, and 246 cases (66.8%) harboured an HAV outbreak strain. Imported frozen berries contaminated with HAV were identified as the vehicle of the outbreak which also involved many other European countries in 2013 and 2014. Epidemiological evidence obtained through a case‐control study was supported by the finding of a 100% nucleotide similarity of the VP1/2A sequences of HAVs detected in human and food samples. Trace‐back investigation revealed an extremely complex supplying network with no possibility for a point source potentially explaining the vast contamination of berries found in Italy. Conclusion. The investigation benefited from an excellent collaboration among different sectors who shared proactively the available information. Our findings highlight the importance of considering frozen berries among the highest risk factors for HAV.

Measles in Italy: Co‐circulation of B3 variants during 2014

In 2013, the majority of the WHO/EUR countries reported an annual incidence of >1 case per one million population indicating that the elimination target is far from being met. Thus, there is the urgent need to uncover and analyze chains of measles virus (MV) transmission with the objective to identify vulnerable groups and avoid possible routes of introduction of MV variants in the European population. The analysis of molecular epidemiology of MV B3 strains identified in 2014 has shown that four different variants co‐circulated in Italy, including the strain that caused a cruise‐line ship outbreak at the beginning of the year. J. Med. Virol. 88:1081–1085, 2016.

Towards measles elimination in Italy: Virological surveillance and genotypes trend (2013-2015)

In accordance with the goal of the World Health Organization Regional Office for Europe, the Italian National Measles and Rubella Elimination Plan aimed to interrupt indigenous measles transmission in Italy by the end of 2015. However, from 2013 to 2015, Italy experienced high measles burden with 4902 measles cases (49.3% laboratory-confirmed) reported to the enhanced measles surveillance system (cumulative incidence in the triennium reference period: 2.4/100,000 population). The measles elimination goal was not reached. Laboratory surveillance of measles circulating genotypes is performed by the Measles and Rubella National Reference Laboratory (NRL) at the Italian National Institute of Health (Istituto Superiore di Sanità - ISS), in Rome. Samples received from 1 January 2013-31 December 2015 were analysed. Those positive for measles genome by molecular tests were sequenced and phylogenetically analysed. Phylogenetic analysis performed by NRL identified that genotypes D4 and D8 were endemic and co-circulated in 2011-2013: study results show that genotype D4 disappeared during 2013. Sporadic cases were associated to genotype B3 during 2011-2013, which became endemic in Italy during 2014 and co-circulated with D8 until 2015. Sporadic cases were found belonging to genotypes D9 and H1 all over the period in exam. Similar trend has been observed in European WHO Region.

Regional reports for the subnational monitoring of measles elimination in Italy and the identification of local barriers to the attainment of the elimination goal

Although most countries in the WHO European Region were verified in 2017 as having interrupted endemic measles transmission, nine countries were still endemic. Among these, Italy accounted for the second highest number of measles cases reported in Europe in 2017. The elimination of measles is verified at national level by each country’s National Verification Committee (NVC) through the production of an Annual Status Update (ASU). Since in Italy decentralization has led to an inhomogeneous implementation of immunization strategies among the 21 administrative Regions, the Italian NVC proposed that measles elimination should also be documented at the subnational level through regional ASUs and Synthetic Regional Reports (SRRs). The regional ASUs and the SRRs for 2014, 2015 and 2016 were produced and appraised by the NVC to evaluate the Regions’ performances in each individual year as well as over the whole period. A specific analysis of vaccination coverage, including official immunization data for 2017, was performed. Moreover, the measles epidemic of 2017 was examined. Firstly, in the period 2014–2016, low immunization rates were registered in most Regions. Sixty-three per cent of southern Regions reported rates below the national mean and an overall low-quality performance. The approval of Italy’s mandatory vaccination law in 2017 resulted in a marked increase in vaccination coverage; however, this increase was not homogeneous among Regions. Secondly, more than 50% of Regions did not report any supplemental immunization activity (SIA) for the period 2014–2016. Thirdly, from 2014 to 2016, fewer than one-third of Regions improved their reporting of outbreaks. Finally, over the study period, only two Regions reached the target required by the WHO for measles laboratory investigations. In countries with decentralized health policies, subnational monitoring can help identify local barriers to measles elimination. In Italy it has highlighted the need for further SIAs and a stronger surveillance system.

Introduction of new and reinforcement of existing compulsory vaccinations in Italy: first evaluation of the impact on vaccination coverage in 2017

In June 2017, a decree-law to increase the number of mandatory vaccinations from 4 to 10 for minors up to 16-years-old was issued in Italy. The vaccination coverage for 2017 showed a positive impact for all the vaccines, particularly for the measles, mumps and rubella vaccine at 91.6% for the year 2017, showing a 4.4% increase compared with 2016 (87.2%). Continued monitoring is needed to evaluate the medium to long-term effects of the law.

Measles in Italy, laboratory surveillance activity during 2010.

INTRODUCTION The European Regional Office of the World Health Organization (WHO/Europe) developed a strategic approach to stop the indigenous transmission of measles in its 53 Member States by 2015. This study describes the measles laboratory surveillance activity performed by the National Reference Laboratory for Measles and Rubella at the Italian National Institute of Health (Istituto Superiore di Sanità) during 2010. METHODS Urine, oral fluid and capillary blood samples from 211 suspected measles cases arrived to the NRL from different regions of Italy for confirmation of the clinical diagnosis. Serological and/or molecular assays were performed; after molecular detection, positive samples were sequenced and genotyped. RESULTS AND DISCUSSION 85% (180/211) of the specimens were confirmed as measles cases and 139 of these were analyzed phylogenetically. The phylogenetic analysis revealed a co-circulation of D4 and D8 genotypes for the reviewed period.