Case-based surveillance of measles in Sicily during 2012-2017: The changing molecular epidemiology and implications for vaccine strategies

Sicilians' knowledge, perceptions, prevention and practices during the pandemic in relation to vaccination: A questionnaire-based survey

BACKGROUND

COVID-19 has influenced Sicily, Italy as any other part of the world, and people had various types of reactions to this global epidemic. This study aimed to assess the behavior, perception, and willingness of the Sicilian population to accept vaccination, as well as their attitudes toward conspiracy theories, which have been a concern for governments around the globe.

METHODS

Study design: cross sectional-descriptive study. The data were collected through a survey developed based on a protocol from the World Health Organization's regional office in Europe, which was distributed in two waves. The first wave took place in April and May 2020, and a modified survey was distributed during June and July.

RESULTS

Sicilians showed a very good knowledge of the virus, while their positive attitude has changed toward vaccination in the second wave. Furthermore, Sicilians showed an average trust in the governmental institutions, which allow the doubts of conspiracy to exist in the population.

CONCLUSIONS

Although the results indicate a good level of knowledge and positive attitude toward vaccination, we believe that further studies should be conducted in the Mediterranean to better understand how to face future epidemics with limited resources in the healthcare system, as compared with other countries.

Measles and Rubella Incidence and Molecular Epidemiology in Senegal: Temporal and Regional Trends during Twelve Years of National Surveillance, 2010-2021

We investigated the epidemiology of measles and rubella infections in Senegal based on data from twelve consecutive years of laboratory-based surveillance (2010−2021) and conducted phylogenetic analyses of circulating measles viruses. Sera from measles-suspected cases were collected and tested for measles and rubella-specific IgM antibodies using enzyme-linked immunosorbent assays (ELISA). Throat swabs were collected from patients with clinically diagnosed measles for confirmation by reverse-transcription polymerase chain reaction (RT-PCR) and viral genotyping. Among 8082 laboratory-tested specimens from measles-suspected cases, serological evidence of measles and rubella infection was confirmed in 1303/8082 (16.1%) and 465/6714 (6.9%), respectively. The incidence of rubella is now low—0.8 (95% CI 0.4−1.3) cases per million people in 2021—whereas progress towards measles pre-elimination targets (<1.0 case per million people per year) appears to have stalled; there were 10.8 (95% CI 9.3−12.5) cases per million people in 2021. Phylogenetic analyses revealed that all Senegalese measles strains belonged to genotype B3. The rubella virus sequence obtained in this study was consistent with genotype 1C. Our national surveillance data suggest that despite their low incidence both measles and rubella remain endemic in Senegal with a concerning stagnation in the decline of measles infections that represents a significant challenge to the goal of regional elimination.

Measles epidemic in pediatric population in Greece during 2017-2018: Epidemiological, clinical characteristics and outcomes

Background and aim

A measles outbreak occurred in Greece during 2017–2018 affecting mainly pediatric population. The aim of the study was to describe the epidemiological and clinical characteristics of the cases diagnosed in the major pediatric tertiary hospital of Athens, where 26.5% of national pediatric measles cases were diagnosed and treated.

Methods

This is a retrospective study of children 0–16 years old, who presented at the emergency department and/or were hospitalized with clinical presentation compatible with measles and diagnosis was confirmed with molecular detection of the measles RNA in pharyngeal swabs. Epidemiological, clinical and laboratory characteristics were retrieved from medical records and analyzed.

Results

A total of 578 children with measles were identified during the study period. 322 (55.7%) were male with median age 36 months (range:1–193), while the largest number of documented cases (251; 43.4%) were children aged 1–5 years. Most children (429/578; 74.2%) belonged to the Roma minority and only 64 (11.1%) had Greek origin. 497 (91.5%) children were unvaccinated and 37 (6.8%) were partially vaccinated with measles vaccine. Hospitalization was required for 342 (59.2%) children, whereas one or more complications were reported in 230 (67.2%) of them. Most frequent complications were elevated transaminases (139; 40.6%), acute otitis media (72; 21%), dehydration (67; 19.6%) and pneumonia (58; 16.9%). 11 children (3.2%) required intensive care admission for altered mental status/status epilepticus (3), sepsis (2) and ARDS (6). 119/342 (34.8%) children were treated with antibiotics because of possible or confirmed bacterial coinfection. One death was reported, concerning an 11-month-old unvaccinated infant, with underlying dystrophy, who died of sepsis.

Conclusion

Measles is not an innocent viral infection, as it is still characterized by high morbidity and complications rates. Unvaccinated or partially vaccinated populations could trigger new outbreaks, resulting in significant cost in public health. To avoid future measles outbreaks, high vaccination coverage should be achieved, as well as closing immunity gaps in the population and ensuring high-quality measles surveillance.

Molecular characterization of measles viruses in China: Circulation dynamics of the endemic H1 genotype from 2011 to 2017

Due to the Expanded Program on Immunization (EPI) and supplementary immunization activities (SIAs) in China, the incidence of measles in China has decreased extensively. The incidence reached its lowest levels in contemporary history in 2012 and 2017, with incidence rates of 4.6 and 4.3 per million population, respectively. However, more than 147,000 measles cases were reported from 2013 to 2016. Furthermore, the proportions of cases in infants < 8 months and adults have been increasing since 2013, representing a considerable challenge for measles elimination in China. A total of 14,868 measles viruses were isolated from confirmed measles cases from 2011 to 2017, of which 14,631 were identified as the predominant endemic genotype, H1; 87 were identified as genotype A viruses that were vaccine associated strains; and 150 were identified as non-H1 genotype viruses. The non-H1 genotype viruses included 62 D8 viruses, 70 D9 viruses, 3 D11 viruses, 14 B3 viruses, and 1 G3 virus, which were identified as imported or import-related viruses that caused sporadic cases or small outbreaks. Most of the transmission chains detected during the period 2011–2012 were interrupted and were followed by many new transmission chains of unknown origin that spread, causing a large measles resurgence in China during 2013–2016. After 4 years of measles resurgence and continuous implementation of the routine immunization program and SIAs, the population immunity reached a sufficiently high level to interrupt most of the transmission chains; only a few strains survived, which continued to be sporadically detected in China in 2017. In the present study, the results from the combined epidemiological and molecular virological data demonstrated the great progress towards measles elimination in China by the further analysis of circulation dynamics for the endemic H1 genotype measles virus from 2011 to 2017. And this study accumulated critical baseline data on circulating wild-type measles viruses in China and provides comprehensive information to the world. These comprehensive baseline data provide evidence to support measles elimination in the future, not only in China but also in other countries worldwide. In addition, the information will be very useful to other countries for tracing their sources of measles cases and for identifying transmission links, which can help prevent potential measles outbreaks.

Measles-Related Hospitalizations in Italy, 2004-2016: The Importance of High Vaccination Coverage

BACKGROUND

Measles is a highly contagious human infectious disease. It can lead to serious complications and often requires hospitalization. In Italy, as in other European countries, the goal of measles elimination in 2015 failed. To reach this target, identifying susceptible individuals, closing any immunity gaps and reaching adequate vaccination coverage is necessary.

OBJECTIVE

To contribute to these purposes, a retrospective observational study on measles-related hospitalization between 2004 and 2016 in Italy was conducted, using the national hospital discharge database as informational flow.

METHODS

Admission frequencies and hospitalization rates were compared between regions with low (<90%) and high (≥90%) vaccination coverage for measles at age 24 months. Categorical variables were analyzed using the χ2 test or the χ2 test for trend for ordinal variables; t test was performed to verify the significance when annual average hospitalization rates were compared. Trends of vaccination coverage and hospitalization rates were analyzed using the slope of the regression line.

FINDINGS

During the study period, 9,546 measles-related hospitalizations were collected in Italy, with an average annual number equal to 734. The overall measles hospitalization rates increased from 0.21 × 100,000 persons in 2004 to 0.82 × 100,000 in 2016 (β = 0.04; p = 0.689). A shift of mean age (from 1-17 years to 18-44 years) of measles-related hospitalizations was shown. A number of admissions for the low vaccination coverage group about twice as much as recorded for the other regional group was shown (6,344 vs 3,202). The involvement of 18-44 age class in the high vaccination coverage group was 14% higher compared with the low vaccination coverage group, in which, however, the 1-17 age class presented a 16% higher frequency.

CONCLUSIONS

These findings confirmed that large measles epidemics continue to occur in Italy, although with regional differences related to different rates of measles immunization. Vaccination coverage >90% led to a halving of measles hospitalizations, but it is insufficient for the elimination: ≥95% coverage continues to be the target to be reached.