Decline in reported measles cases in Italy in the COVID-19 era, January 2020 - July 2022: The need to prevent a resurgence upon lifting non-pharmaceutical pandemic measures

Measles in Czech population with varying vaccination rates in 2018-2019: clinical and laboratory differences between vaccinated and unvaccinated individuals and their relevance to clinical practice

BACKGROUND AND OBJECTIVES

In a highly vaccinated population, an increasing number of previously vaccinated measles cases can be expected. The aim of this study was to assess the effect of vaccination on the clinical course and immune response in relation to the current measles case definition.

METHODS

The presence of fever, catarrhal symptoms, exanthema and complications, and specific IgM and IgG positivity were assessed in all 230 patients and compared in 193 patients with known vaccination status, divided into measles-containing vaccine (MCV) groups: MCV0 (85 patients), MCV1 (25 patients) and MCV2 (83 patients).

RESULTS

Statistically significant differences between groups were found for catarrhal symptoms. Conjunctivitis and rhinitis were significantly less frequent in the MCV2 group (47% and 54%) compared to MCV0 (80% and 80%), p < 0.001 and p = 0.002 respectively. Typical exanthema was present in 74 (87%) MCV0 and 56 (67%) MCV2 patients, p = 0.005. Complications were most common in the MCV0 group (29%). ECDC clinical case criteria were met in 81 (95%) MCV0, 18 (72%) MCV1 and 59 (71%) MCV2 patients, p < 0.001. IgM were positive in 64 (83%) MCV0, 14 (74%) MCV1 and 36 (67%) MCV2 patients, differences were not statistically significant. There were highly significant differences in IgG between MCV0 and both vaccinated groups (p < 0.001).

CONCLUSIONS

A redefinition of the clinical case classification is essential to better capture modified measles and to raise awareness among healthcare workers of the differences in measles in vaccinated patients.

Assessing the Impact of the COVID-19 Pandemic on Pregnant Women's Attitudes towards Childhood Vaccinations: A Cross-Sectional Study

The COVID-19 pandemic has globally disrupted immunisation practices, impacting vulnerable populations such as pregnant women (PW), who harbour concerns about future children's immunisations. This study aimed to assess the pandemic's impact on PW's attitudes towards childhood vaccinations. During three consecutive flu seasons from October 2019 to January 2022, a cross-sectional study was conducted in a large Italian teaching hospital using a questionnaire. The chi-square test was performed to compare each season. Across the 2019-2020 to 2021-2022 seasons, course attendance by PW surged from 105 to 340. Significant shifts in vaccination intentions were noted, including a 7.5% decrease in measles vaccination intent (p = 0.02) and a 10% decrease in that of pertussis (p = 0.004) from 2019-2020 to 2020-2021. While perceived contagion risk decreased, disease severity perceptions increased, with few significant differences. A statistically significant reduction was noted in the proportion of participants suspecting economic motives behind NHS workers' promotion of childhood vaccinations. Furthermore, the pandemic period saw an increase in the perceived utility of non-institutional websites and the advice of physicians outside the NHS. These findings will help develop evidence-based, tailored interventions and communication strategies to address vaccine hesitancy and ensure optimal vaccination coverage among children born during and after the pandemic.

Long-lasting effects of COVID-19 pandemic on hospitalizations and severity of bronchiolitis

Bronchiolitis is a common cause of hospitalization in infants. The long-lasting impact of hygiene and social behavior changes during the pandemic on this disease is debated. We investigated the prevalence of hospitalized cases, clinical severity, and underlying risk factors before and during pandemic. The study was conducted in 27 hospitals in Italy and included infants hospitalized for bronchiolitis during the following four periods: July 2018-March 2019, July 2020-March 2021, July 2021-March 2022, and July 2022-March 2023. Data on demographics, neonatal gestational age, breastfeeding history, underlying chronic diseases, presence of older siblings, etiologic agents, clinical course and outcome were collected. A total of 5330 patients were included in the study. Compared to 2018-19 (n = 1618), the number of hospitalizations decreased in 2020-21 (n = 121). A gradual increase was observed in 2021-22 (n = 1577) and 2022-23 (n = 2014). A higher disease severity (need and length of O2-supplementation, need for non-invasive ventilation, hospital stay) occurred in the 2021-22 and, especially, the 2022-23 periods compared to 2018-19. This tendency persisted after adjusting for risk factors associated with bronchiolitis severity.   Conclusions: Compared to adults, COVID-19 in infants is often asymptomatic or mildly symptomatic and rarely results in hospitalization. This study indicates that the pandemic has indirectly induced an increased burden of bronchiolitis among hospitalized infants. This shift, which is not explained by the recognized risk factors, suggests the existence of higher infant vulnerability during the last two seasons. What is known: • The pandemic led to a change in epidemiology of respiratory diseases • Large data on severity of bronchiolitis and underlying risk factors before and during COVID-19 pandemic are scarce What is new: • Compared to pre-pandemic period, hospitalizations for bronchiolitis decreased in 2020-21 and gradually increased in 2021-22 and 2022-23 • Compared to pre-pandemic period, higher disease burden occurred in 2021-22 and, especially, in 2022-23. This tendency persisted after adjusting for risk factors associated with bronchiolitis severity • The interplay among viruses, preventive measures, and the infant health deserves to be further investigated.

Differential diagnosis of fever and rash cases negative for measles and rubella to complement surveillance activities

In the quest to eliminate measles virus (MV) and rubella virus (Ruv), every suspected case must be properly identified and diagnosed. Since 2017, in Milan (Italy), a total of 978 measles and rubella suspected cases (fever and rash) were investigated and 310 were not laboratory confirmed (discarded cases). To improve surveillance activities, we investigated the presence in discarded cases of 8 other viral pathogens commonly associated with rash: human herpesvirus 6 (HHV-6) and 7 (HHV-7), parvovirus B19 (B19V), enterovirus (EV), Epstein-Barr virus (EBV), human adenovirus (HAdV), cytomegalovirus (HCMV), and SARS-CoV-2. Differential diagnosis was carried out on 289 discarded cases by multiplex real-time PCR assays. At least one pathogen was detected in 188 cases (65.1%) with HHV-7 being the most frequently detected virus. No difference in the number of detected infections overtime was observed and infections were identified in all age groups. As expected, most HHV-6, EV, HAdV, and HCMV-positive cases were found in children aged 0-4 years and HHV-7 was most frequent in the 15-39 age group. In light of the World Health Organization measles elimination goal, the introduction of laboratory methods for differential diagnosis is required for the final classification of clinically compatible cases. The used screening panel allowed us to increase the percentage of virus-positive cases to 87.5%, allowing us to clarify viral involvement and epidemiology, improve diagnosis, and strengthen surveillance activities. As all investigated pathogens were detected, this diagnostic panel was a suitable tool to complement MV and RuV surveillance activities.