Rapid molecular epidemiology investigations into two recent measles outbreaks in Israel detected from October 2023 to January 2024.

Between late 2023 and early 2024, two measles outbreaks occurred in Israel, each caused by importation of measles virus strains of respective B3 and D8 genotypes. In this study, we validate transmission pathways uncovered by epidemiological investigations using a rapid molecular approach, based on complete measles virus genomes. The presented findings support this rapid molecular approach in complementing conventional contact tracing and highlight its potential for informing public health interventions.

Demographic and clinical characteristics of children and adolescents hospitalised with laboratory-confirmed COVID-19 in the Tel-Aviv District, Israel, 2020-2022.

Our study population consisted of all children and adolescents, with laboratory-confirmed SARS-Co-V-2 infection, hospitalised from February 2020 through February 2022, among residents of the Tel Aviv (TA) District, Israel. There were 491 children and adolescents hospitalised with Sars-CoV-2 infection. Among them, 281 (57%) admitted with coronavirus disease 2019 (COVID-19) as the primary cause of admission (rate of 39 per 100 000). Among all children and adolescents in the TA District, the highest hospitalisation rates were observed among infants and children below the age of 4 years (rate of 311 per 100 000 population). Severe disease was observed mostly among children with multiple underlying medical conditions. Admission rates were also elevated among residents of the ultra-orthodox community (rate ratio (RR) compared to the rest of the district; 95% confidence interval (CI) 2.38-3.82). Admission rates with COVID-19 as primary cause of admission were higher during Omicron compared to Delta predominance period (RR 1.7; 95% CI 1.22-2.32). Targeted social and public health policies should be put in place when rates of disease start to increase, such as encouraging vaccine uptake for eligible children and social distancing when necessary, taking into account already existing social and learning gaps, in order to reduce the burden of disease.

A Measles Outbreak in the Tel Aviv District, Israel, 2018-2019.

During a national measles outbreak in 2018-2019, the Tel Aviv District suffered a major upsurge of cases, with 413 patients reported. Among them, 100 (24%) were <1 year, 92 (22%) patients were aged 12 months to 4 years, 47 (11%) were 5-18 years, 169 (41%) were 19-60 years, and 5 (1%) patients were older than 61 years (born before 1957). Among all cases, 230 (56%) were part of the Ultra-Orthodox Jewish community, 55 (13%) were among undocumented African immigrants. Despite high vaccination coverage, sustained measles transmission occurred, due in part to importations and numerous exposures in medical settings by a susceptible birth cohort. The Ultra-Orthodox Jewish community was particularly afflicted due to its condense population, high birth rates, and multiple exposures in crowded religious settings. This outbreak demonstrates the necessity of addressing immunity gaps as well optimal healthcare planning in order to prevent future outbreaks.

Measles outbreak associated with a preschool setting among partially vaccinated children in the Tel Aviv District, Israel, October 2023.

In October 2023, the Tel Aviv District was notified of ten cases of measles. The outbreak initiated in a preschool with high vaccination coverage with one dose of MMR vaccine. Serological testing was available for eight patients (six children and two adults). Among the six children vaccinated with one dose of MMR vaccine, primary vaccine failure was demonstrated. Among the adults, secondary vaccine failure was confirmed. The outbreak was successfully contained due to a combination of factors, notably its occurrence within a population characterized by high vaccination coverage in Tel Aviv, during a period of restricted public interactions due to the prevailing state of war in the country. Despite challenging wartime conditions, effective prophylactic measures were promptly executed, encompassing a 2-dose MMR vaccination schedule for close contacts and the broader community of children in the TA district, successfully curbing the outbreak and preventing widespread infections.

Monkeypox outbreak in the Tel Aviv District, Israel, 2022.

OBJECTIVES: From May-September 2022, 203 cases of monkeypox (MPX) were reported in the Tel Aviv (TA) District, Israel. We aim to report the first ongoing local transmission of MPX in Israel. METHODS: We analyzed the epidemiologic and clinical features of all cases of MPX notified to the TA District. Each case was contacted to verify the source of infection and locate potential contacts. RESULTS: All cases were men; 195 (96%) were among men having sex with men, and 171 (84%) resided in the city of TA. Median age was 35 years. One case occurred in a healthcare worker. All cases had a self-limiting disease. CONCLUSION: A combined public health campaign with vaccination against MPX of high-risk individuals leads to a decrease in disease rates. Enhanced surveillance and prevention among susceptible populations are warranted.

Pediatric measles cases by residence status in Tel Aviv, Israel.

BACKGROUND: Measles is a vaccine-preventable infectious disease whose outbreaks generally originate from exposure to populations with low vaccination coverage. METHODS: This study compared the rates and morbidity of measles cases in the district of Tel-Aviv during two outbreaks (2012 and 2018-2019) by citizenship and geographic location. RESULTS: There were 67 pediatric cases reported in 2012 and 222 in 2018-2019. Cases were more likely to have pneumonia in 2012 as compared to in 2018-2019 (58.2% versus 6.3%) and less likely to report a single vaccination dose (9.5% versus 22.8%, respectively). In 2012, the majority of cases were among children without legal residence (CWLR), while in 2018-2019, they were the minority of cases (N = 54, 80.6% versus N = 51, 23.0%, respectively). In both outbreaks, CWLR were more likely to be less than one year old (the recommended age for the first dose of measles vaccination), unvaccinated or with unknown vaccine status, to be treated in a tertiary care center, and to have pneumonia than children with Israeli citizenship (CC). In both outbreaks, CWLR lived in a concentrated neighborhood in Southern Tel Aviv. CONCLUSION: While the two measles outbreaks differed in overall morbidity, in both outbreaks CWLR presented with a more severe clinical presentation and were less likely to be vaccinated (in part due to their younger age) than CC. The geographically concentration of CWLR was distinct from that of the CC in both outbreaks. Healthcare professionals should promote vaccination uptake and increase parents' awareness to early signs of the disease.

Surveillance of invasive meningococcal disease in the Tel Aviv District, Israel, 2007-2017.

Invasive meningococcal disease (IMD) is one of the leading causes of bacterial meningitis and septicemia in Israel. The purpose of the study was to describe the IMD in the Tel Aviv District and to identify specific populations who could benefit from vaccine introduction. In the Tel Aviv District, the incidence rates ranged from 0.4 to 1.4 cases per 100,000 population per year during 2007-2017. During the study period, seventy-nine patients (65%) occurred among children younger than four years of age. Eight deaths occurred (7%), most of them among children under the age of 1 year (5 deaths; 15%). A serogroup was identified in 82 isolates. Most of the isolates (69 cases - 84%) belonged to serogroup B (NmB). IMD clustered geographically in the city of Bnei Brak, with a predominantly Ultra-Orthodox Jewish population. It is the youngest and most densely populated city in the district. The overall incidence rates of IMD among children in Bnei Brak were more than seven times higher in children up to nine years, compared to the rest of the district. Specifically for NmB, disease rates were 9.08 times higher in children up to the age of four, and 7.74 times higher in children from five to nine years old in Bnei Brak, compared to the rest of the district. Our findings describe the burden of a vaccine-preventable disease and reinforce the need for routine 4CmenB introduction, especially in groups where the disease clusters.

Outbreak of West Nile Virus disease in Israel (2015): A retrospective analysis of notified cases.

BACKGROUND: West Nile Virus (WNV) is mosquito-borne virus that is endemic in Israel. In 2015, national disease surveillance demonstrated a sharp increase in disease cases, with 149 cases diagnosed. METHODS: Clinical data was extracted from the patients' medical files and laboratory analysis on blood, cerebrospinal fluid or urine was carried out. Data on climate was extracted from the Israel Meteorological Service. RESULTS: Neuroinvasive disease was reported in 70% of cases and case-fatality rate was 16%. Simultaneously with the outbreak, an intense heat wave and an upsurge in summer temperatures occurred. CONCLUSIONS: Clinical data shows substantial morbidity and mortality of WNV disease in Israel. Climatic measures are consistent with previous reports and point to the importance of temperature monitoring and rapid implementation of preventive environmental measures during the summer to reduce potential mosquito breeding sites. WNV disease should be suspected as a cause of fever or neurologic disease in travelers returning from endemic countries.

Outbreak of adenovirus type 55 infection in Israel.

BACKGROUND: Different types of adenoviruses are associated with diverse diseases and with varied disease severity. Adenovirus 55 could be associated with severe respiratory infections. OBJECTIVES: Here, we report on an adenovirus 55 outbreak in two psychiatric institutions in Israel. The objective of this study was to investigate the adenovirus 55 outbreak. STUDY DESIGN: We studied the clinical parameters of the patients and sequencing analysis of certain parts of the virus gene was performed. RESULTS: We identified the first patient who developed symptoms (the index case) and we showed that while both patients and staff members of the institutions were infected, the disease in the psychiatric patients was more severe. We attributed these differences to their mental and underlying health conditions. CONCLUSIONS: It is important to monitor for adenovirus infection in the community, especially in mental health institutions to allow appropriate medical care.