Extensive Nosocomial Transmission of Measles Originating in Cruise Ship Passenger, Sardinia, Italy, 2014

Temporal and spatial analysis of over 7,000 measles cases outbreak from 2018 to 2019 in the Brazilian Amazon

OBJECTIVE

This study aimed to present a temporal and spatial analysis of the 2018 measles outbreak in Brazil, particularly in the metropolitan city of Manaus in the Amazon region, and further introduce a new tool for spatial analysis.

METHODS

We analyzed the geographical data of the residences of over 7,000 individuals with measles in Manaus during 2018 and 2019. Spatial and temporal analyses were conducted to characterize various aspects of the outbreak, including the onset and prevalence of symptoms, demographics, and vaccination status. A visualization tool was also constructed to display the geographical and temporal distribution of the reported measles cases.

RESULTS

Approximately 95% of the included participants had not received vaccination within the past decade. Heterogeneity was observed across all facets of the outbreak, including variations in the incubation period and symptom presentation. Age distribution exhibited two peaks, occurring at one year and 18 years of age, and the potential implications of this distribution on predictive analysis were discussed. Additionally, spatial analysis revealed that areas with the highest case densities tended to have the lowest standard of living.

CONCLUSION

Understanding the spatial and temporal spread of measles outbreaks provides insights for decision-making regarding measures to mitigate future epidemics.

Vaccination Offer during the Occupational Health Surveillance Program for Healthcare Workers and Suitability to Work: An Italian Retrospective Cohort Study

The active immunization of health care workers (HCWs) is a crucial measure to avoid nosocomial infection; nevertheless, vaccine coverage (VC) among health personnel in Italy is unsatisfactory. To improve VC in the healthcare set, the Hygiene and Occupational Medicine departments of Bari Policlinico General University Hospital applied a specific program. The operative procedure demands that in the context of the occupational medical examination, all workers are evaluated for susceptibility to vaccine-preventable diseases (VDPs), with immunization prophylaxis offered to those determined to be susceptible. This study analyzed data from workers who attended the biological risk assessment protocol from December 2017 to October 2021 (n = 1477), who were evaluated for the immune status for measles, mumps, rubella, and varicella. Among the enrolled subjects, non-protective antibody titers were higher for measles and mumps (13%), followed by rubella (11%) and varicella (8%). Appropriate vaccinations were offered to all susceptible HCWs, and HCWs were re-tested one month after immunization. The seroconversion rate after the administration of one or more booster dose(s) was over 80%. Overall, 2.5% of the subjects refused the offered vaccine(s); the main determinant of immunization compliance was younger age (aOR = 0.86; 95%CI = 0.80–0.92). Especially during the COVID-19 pandemic, VPDs may still present a hazard in nosocomial environment. Our experience suggests that, despite hospital procedures and dedicated human assets, satisfactory VC cannot be reached without the provision of federal regulations. Nevertheless, public health policymakers have to improve the promotion of vaccine prophylaxis and education to reach higher VC.

Measles among healthcare workers in Italy: is it time to act?

Vaccination of healthcare workers (HCWs) against measles is strongly recommended in Europe. In this study, we examined the impact of measles on Italian HCWs by systematically and quantitatively analyzing measles cases involving HCWs over time and by identifying the epidemiological characteristics of the respective measles outbreaks. We retrieved data on measles cases from the Italian national integrated measles and rubella surveillance system from January 2013 to May 2019. Additionally, we performed a systematic review of the literature and an analysis of the measles and rubella aggregate outbreaks reporting forms from 2014 to 2018. Our review suggests that preventing measles infection among HCWs in disease outbreaks may be crucial for the elimination of measles in Italy. National policies aiming to increase HCW immunization rates are fundamental to the protection of HCWs and patients, will limit the economic impact of outbreaks on the institutions affected and will help achieve the elimination goal.

Compliance with immunization and a biological risk assessment of health care workers as part of an occupational health surveillance program: The experience of a university hospital in southern Italy

BACKGROUND

The active immunization of health care workers (HCWs) is a primary measure to prevent nosocomial infection; despite this, vaccine coverage among HCWs in most countries is low. To increase vaccine coverage in the health care setting, the hygiene and occupational medicine departments of Bari Policlinico General University-Hospital implemented a vaccination procedure. This operative procedure requires that during the occupational medical examination, all employees are evaluated for immunity/susceptibility to vaccine-preventable diseases, with vaccination offered to those determined to be susceptible.

METHODS

The study sample comprised HCWs who attended the biological risk assessment program from December 2017 to January 2019 (n = 449).

RESULTS

Susceptibility was higher for hepatitis B virus (23%), followed by rubella (11%), varicella (9%), mumps (8%), and measles (7%). The seroconversion rate after the administration of booster dose(s) was >80% for all vaccines. Overall, 15% of the HCWs refused the offered vaccine(s), and the main determinants of vaccination compliance were younger age (P < .0001) and being a physician (P < .05).

DISCUSSION

Despite the several recommendations and campaigns to promote vaccinations, achieving high immunization rates among HCWs is still a challenge.

CONCLUSIONS

In this scenario, public health institutions have to choose between the enforcement of the promotion or the adoption of a mandatory policy.

Measles recognition during measles outbreak at a paediatric university hospital, Austria, January to February 2017

Recognition of measles is crucial to prevent transmissions in the hospital settings. Little is known about the level of recognition of measles and possible causes of not recognising the disease by physicians in the post-vaccine era. We report on a measles outbreak in a paediatric hospital in Austria in January to February 2017 with strikingly high numbers of not recognised cases. The extent and course of the outbreak were assessed via retrospective case finding. Thirteen confirmed measles cases were identified, two with atypical clinical picture. Of eight cases with no known epidemiological link, only one was diagnosed immediately; four were recognised with delay and three only retrospectively. Eleven typical measles cases had four ‘unrecognised visits’ to the outpatient clinic and 28 on the ward. Two atypical cases had two ‘unrecognised visits’ to the outpatient clinic and 19 on the ward.

Thirteen clinicians did not recognise typical measles (atypical cases not included). Twelve of 23 physicians involved had never encountered a patient with measles before. The direct and indirect costs related to the outbreak were calculated to be over EUR 80,000. Our findings suggest the need to establish regular training programmes about measles, including diagnostic pitfalls in paediatric hospitals.

Towards elimination of measles and rubella in Italy: Progress and challenges

INTRODUCTION

In the WHO European Region, endemic transmission of measles and rubella had been interrupted by 37 and 42 of the 53 member states (MSs), respectively, by 2018. Sixteen MSs are still endemic for measles, 11 for rubella and nine for both diseases, the latter including Italy. Elimination is documented by each country's National Verification Committee (NVC) through an annual status update (ASU).

OBJECTIVE

By analysing data used to produce the ASUs, we aimed to describe the advances made by Italy towards elimination of measles and rubella. Moreover, we propose a set of major interventions that could facilitate the elimination process.

METHODS

A total of 28 indicators were identified within the six core sections of the ASU form and these were evaluated for the period 2013-2018. These indicators relate to the incidence of measles/rubella; epidemiological investigation of cases; investigation of outbreaks; performance of the surveillance system; population immunity levels; and implementation of supplemental immunization activities (SIAs).

RESULTS

From 2013 to 2018, epidemiological and laboratory analyses of measles cases in Italy improved substantially, allowing timely investigation in 2017 and 2018 of most outbreak and sporadic cases and identification of the majority of genotypic variants. Moreover, since 2017, vaccination coverage has increased significantly. Despite these improvements, several areas of concern emerged, prompting the following recommendations: i) improve outbreak monitoring; ii) strengthen the MoRoNet network; iii) increase the number of SIAs; iv) reinforce vaccination services; v) maintain regional monitoring; vi) design effective communication strategies; vii) foster the role of general practitioners and family paediatricians.

CONCLUSIONS

The review of national ASUs is a crucial step to provide the NVC with useful insights into the elimination process and to guide the development of targeted interventions. Against this background, the seven recommendations proposed by the NVC have been shared with the Italian Ministry of Health and the Technical Advisory Group on measles and rubella elimination and have been incorporated into the new Italian Elimination Plan 2019-2023 as a technical aid to facilitate the achievement of disease elimination goals.

Analysis of a 3-months measles outbreak in western Liguria, Italy: Are hospital safe and healthcare workers reliable?

BACKGROUND

From January 2017 to June 2018 more than 7000 measles cases were reported in Italy, of which more than 400 among unvaccinated healthcare workers. We described a measles outbreak occurred in Western Liguria, Italy, characterized by a high involvement of healthcare workers and hospital visitors.

METHODS

Suspected measles cases and data regarding vaccination status and clinical management of the patients were collected by reviewing 3 different surveillance systems: the routine mandatory notification system, the National Integrated Surveillance System for Measles and Rubella and the regional reference laboratory for measles diagnosis.

RESULTS

Thirty-six cases were reported, with a median age of 31 years and >95% in unvaccinated subjects. One death occurred, 15 cases were hospitalized. Hospital transmission was confirmed or suspected in 12 cases; amongst this cases, 5 were healthcare workers (a gynaecologist, an obstetric nurse, a radiologist, a physiotherapist and a nurse working in an infectious disease ward), all certified unvaccinated. Phylogenetic analysis revealed the circulation of a single B3 genotype variant.

CONCLUSIONS

Our experience highlighted the key role of nosocomial transmission and the need for targeted strategies, in particular (i) to implement a measles catch-up immunization campaign in susceptible groups, especially in healthcare workers, (ii) to intensify the check of immunisation status of healthcare workers and to offer vaccination for those who need it, (iii) to improve timeliness and completeness of surveillance systems. Efforts are needed to guarantee the safety of the hospital and the reliability of the healthcare workers. Only high vaccination coverage among HCWs can prevent the diffusion of measles in the hospital setting.

A national measles outbreak in Ireland linked to a single imported case, April to September, 2016

Endemic measles transmission was interrupted for the first time in Ireland in 2015. In May 2016, a case of measles was confirmed in an adult who had travelled from Hungary to Ireland (index case). Cases subsequently arose in five of the eight public health regions around the country. There were 40 confirmed cases in Ireland between April and September 2016. All sequenced cases were genotype B3. Vaccination status was known for 34 cases, of whom 31 were unvaccinated. Median age was 8 years (range: 3 months to 40 years). Ten cases were nosocomial, and three cases were infected on separate international flights. One linked case occurred in a resident of Slovenia. Nineteen cases were hospitalised; median duration of hospitalisation was 5 days (range: 2–8 days). The primary case was a child who travelled from Romania to Ireland via Budapest, and infected the index adult case on the same flight. This was the first reported outbreak of measles genotype B3 in Ireland. This outbreak demonstrated that Ireland remains at risk of measles outbreaks due to persistent suboptimal vaccination rates.

A Systematic Review for Vaccine-Preventable Diseases on Ships: Evidence for Cross-Border Transmission and for Pre-Employment Immunization Need

A literature review was conducted to identify evidence of cases and outbreaks of vaccine-preventable diseases (VPDs) that have been reported from on board ships and the methods applied on board for prevention and control, worldwide, in 1990 to April 2019. Moreover, evidence from seroprevalence studies for the same diseases were also included. The literature review was conducted according to Preferred Reporting Items for Systematic reviews (PRISMA) guidelines. A total of 1795 cases (115 outbreaks, 7 case reports) were identified, the majority were among crew (1466/1795, 81.7%) and were varicella cases (1497, 83.4%). The origin of crew cases was from sub-tropical countries in many reports. Measles (40 cases, 69% among crew), rubella (47, 88.7%), herpes zoster (9, 69.2%) and varicella cases (1316, 87.9%) were more frequent among crew. Mumps cases were equal among passengers and crew (22/22). Hepatitis A (73/92, 70.3%), meningococcal meningitis (16/29, 44.8%), and pertussis (9/9) were more frequent among passengers. Two outbreaks resulted in 262 secondary measles cases on land. Review results were used to draft a new chapter for prevention and control of VPDs in the European Manual for Hygiene Standards and Communicable Disease Surveillance on Passenger Ships. Despite past and current evidence for cross-border VPD transmission and maritime occupational risks, documented pre-employment examination of immune status, vaccination of seafarers, and travel advice to passengers are not yet regulated.

Screening of more than 2000 Hungarian healthcare workers' anti-measles antibody level: results and possible population-level consequences

Due to the European measles epidemic and the increased number of imported cases, it can be theorised that the risk of exposure among Hungarian healthcare workers (HCWs) has increased. In 2017, the increased measles circulation in the region led to the emergence of smaller local and hospital epidemics. Therefore, our objective was to determine the herd immunity in the high-risk group of HCWs. A hospital-based study of detecting anti-measles IgG activity was performed in 2017 and included 2167 employees of the Military Medical Centre (Hungary). The screening of HCWs presented a good general seropositivity (90.6%). The highest seroprevalence value (99.1%) was found in the age group of 60 years or older. The lowest number of seropositive individuals was seen in the 41-45 years (86.2%) age group, indicating a significant herd immunity gap between groups. Regarding the Hungarian data, there might be gaps in the seroprevalence of the analysed HCWs, implying that susceptible HCWs may generate healthcare-associated infections. This study suggests that despite the extensive vaccination and high vaccine coverage, it is still important to monitor the level of protective antibodies in HCWs, or in a representative group of the whole population of Hungary, and possibly in other countries as well.

Ongoing outbreak with well over 4,000 measles cases in Italy from January to end August 2017 - what is making elimination so difficult?

We report an ongoing measles outbreak in Italy, with over 4,400 cases reported in 20 Regions from January to August 2017. Median age was 27 years, 88% of the cases were unvaccinated. The highest incidence was in infants below one year of age and 7% of cases occurred among healthcare workers. Three deaths occurred and two cases of encephalitis were reported. Wide immunity gaps and nosocomial transmission are major challenges to measles elimination in Italy.

A nosocomial measles outbreak in Italy, February-April 2017

We describe a nosocomial outbreak of measles that occurred in an Italian hospital during the first months of 2017, involving 35 persons and including healthcare workers, support personnel working in the hospital, visitors and community contacts. Late diagnosis of the first case, support personnel not being promptly recognised as hospital workers and diffusion of the infection in the emergency department had a major role in sustaining this outbreak.

Transmission of measles among healthcare Workers in Hospital W, Xinjiang Autonomous Region, China, 2016

Background

As China approaches the elimination of measles, outbreaks of measles continue to occur. Healthcare workers (HCWs) are known to be at high risk of infection and transmission of measles virus. A measles outbreak occurred in a hospital in Xinjiang Uighur Autonomous Region of the People’s Republic of China. We report an investigation of this outbreak and its implications for measles elimination and outbreak preparedness.

Methods

We conducted a retrospective search for measles cases using hospital records. Information on cases was collected by interview, and was used to determine epidemiological linkages. We surveyed HCWs to determine their demographic characteristics, disease history and vaccination status, and knowledge about measles.

Results

We identified 19 cases, ages 18 to 45 years, in Hospital W between December 2015 and January 2016; 14 were laboratory-confirmed, and 5 were epidemiologically linked. The primary case was a 25-year-old neurology department nurse who developed a rash on 22 December 2015 that was reported on 11 January 2016. She continued working and living with her workmates in a dormitory during her measles transmission period. Among the 19 infected HCWs, 2 had received a dose of measles-containing vaccine (MCV) before the outbreak, and 16 had unknown vaccination status. Outbreak response immunization activities were started on 8 January in a non-selective manner by offering vaccine regardless of vaccination history; 605(68%) of 890 HCWs were vaccinated. The HCW survey had a 73% response rate (646/890); 41% of HCWs reported that they had received MCV before outbreak, and 56% exhibited good knowledge of measles symptoms, transmission, complications, and vaccination.

Conclusions

Low MCV coverage, low measles knowledge among HCWs, delayed reporting of measles cases, and absence of proper case management were associated with this outbreak. Training and vaccinating HCWs against measles are essential activities to prevent measles virus transmission among HCWs.

Outbreak of a new measles B3 variant in the Roma/Sinti population with transmission in the nosocomial setting, Italy, November 2015 to April 2016

A measles outbreak occurred from November 2015 to April 2016 in two northern Italian regions, affecting the Roma/Sinti ethnic population and nosocomial setting. Overall, 67 cases were reported. Median age of 43 cases in three Roma/Sinti camps was four years, nosocomial cases were mainly adults. The outbreak was caused by a new measles virus B3.1 variant. Immunisation resources and strategies should be directed at groups with gaps in vaccine coverage, e.g. Roma/Sinti and healthcare workers.

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.