Early rise of West Nile fever in Israel, June 2024.

This report describes an unusual surge of West Nile fever in Israel in June 2024, during which 125 cases were diagnosed, compared with 4 cases on average during June in previous years (2014-23). Of the cases, 64 (62.1%) had neuroinvasive disease and 12 (9.6%) died; the 2024 case fatality rate was not significantly elevated vs the average rate in 2014-23. The early rise could be related to a temperature increase in spring and early summer of 2024.

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.

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.

A retrospective cohort analysis of treatment outcomes of patients with tuberculosis who used substances in Tel Aviv, Israel.

AIMS: To outline the demographic, clinical, laboratory characteristics, and treatment outcomes of tuberculosis (TB) patients who used substances. METHODS: This retrospective cohort study compared 50 TB patients who used substances with a matched random sample of 100 TB patients who did not use substances between 2007 and 2017. Treatment failure was defined as a sputum smear or culture that tested positive after 5 months of treatment, loss to follow-up, unevaluated patients, or death. RESULTS: TB patients who used substances were typically younger, experienced homelessness, smokers, and had fewer chronic diseases than those who did not use substances. They also were hospitalized for longer periods, their treatment durations were longer, had higher rates of multidrug resistant strains, increased rates of treatment failure, and higher mortality. Individuals whose treatment failed predominantly originated from the former Soviet Union, experienced homelessness, and had chronic diseases compared with those whose treatment was successful. In the multivariate analysis, homelessness [odds ratios (OR) = 6.7], chronic diseases (OR = 12.4), and substance use (OR = 4.0) were predictors of treatment failures. CONCLUSIONS: TB patients who used substances were more likely to have treatment failure. Targeted interventions, including early diagnosis and enhanced support during treatment, are essential to achieve treatment success in this vulnerable population, in addition to TB-alcohol/drug collaborative activities.

Hepatitis C Virus Elimination Program among Prison Inmates, Israel.

The Israeli Prison Services implemented a hepatitis C virus (HCV) elimination program in 2020. Inmates considered high risk for HCV were offered serology; HCV-seropositive participants were offered HCV RNA testing. Among participants, 7.0% had detectable HCV RNA and were offered antiviral drug therapy. This program reduced HCV burden among incarcerated persons.

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.

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.

Morbidity among Israeli backpack travelers to tropical areas.

BACKGROUND: Travelers to tropical areas may be susceptible to illness or injuries. This study aims to assess morbidity among travelers during their travel and compare those who became ill or were injured with those who did not. METHODS: This prospective study included 400 travelers who were counselled by a physician in pre-travel clinics in central Israel between 2017 and 2018. Participants were interviewed within a month after their return regarding morbidity during travel, including health problems that started one week following their return. RESULTS: Most travelers (N = 320, 80%) reported at least one illness or injury. Illnesses/injuries were more common among females than males (84.9% vs. 75.1%, p = 0.01), travel periods longer than 30 days (87.7% vs. 77.2%, p = 0.03), and travelers accompanied by their friends or solo travelers compared with those who traveled with their family/partner (83.8% and 70.0%, respectively, p = 0.002). The most common complaint was diarrhea (N = 159, 49.6%), followed by high-altitude sickness (N = 118, 36.9%) and fever (N = 100, 31.2%). Altitude sickness symptoms were more common in females than in males (58.9% vs. 41.0%, p = 0.006) and in those who ascended rapidly in comparison to those who ascended gradually (58.7% vs. 44.6%, p = 0.04). Animal injury was reported by 30 (7.5%) participants yet only eight (27.0%) received medical care, seven of whom (23.3%) were vaccinated against rabies. CONCLUSIONS: Being a female, traveling with friends or alone and longer travel periods were associated with illness/injury. Practitioners at pre-travel clinics should inform travelers of the possible risks including the potential severe consequences of rabies and altitude sickness.

Adherence to antimalarial chemoprophylaxis among Israeli travelers visiting malaria-endemic areas.

BACKGROUND: Travelers are recommended to take antimalarial chemoprophylaxis (AMC) when traveling to endemic areas. METHODS: This prospective comparative cohort study included 400 Israeli travelers to malaria-endemic areas, recruited in pre-travel clinics. They were contacted within one month following their return and asked about their actual adherence and the reasons for non-adherence. RESULTS: Of 400 travelers with a mean age of 24.6 [SD = 4] years, 201 (50.2%) were men and 328 (82%) were singles. The majority (N = 185, 46.3%) traveled with friends, and the most common travel destination was southeast Asia (N = 267, 66.8%). Most travelers (N = 340, 85%) did not adhere to the AMC. In the multivariate analysis, non-adherence was found to be significantly associated with traveling solo or with friends, traveling to southeast Asia and longer travel duration. The most common reason for non-adherence among travelers was the perception that the risk of contracting malaria is low (N = 251, 73.8%). CONCLUSION: In this study, 85% of the Israeli travelers did not adhere to the AMC, especially those traveling solo or with friends, visiting southeast Asia and for a long period. Counselors at the pre-travel clinics should stress the importance of AMC in highly endemic countries and consider alternative treatment strategies, especially in low risk areas or long duration travel, such as short-term schedule or reserve AMC for field trips.

Reduction in self-reported influenza-like-illness in school children and household members following influenza vaccine administration - a cohort study, Israel, 2016-7.

BACKGROUND: Second-grade pupils in Israel have been vaccinated against influenza since the winter of 2016-2017. This study aims to appraise the rate reduction of seasonal influenza vaccine among vaccinated children and their household members, and that of the vaccinated cohort and their household members. METHODS: This retrospective cohort study was performed in winter 2016-2017 in Tel-Aviv District, Israel and compared second-grade pupils who were vaccinated at school, with third-grade pupils- who were not vaccinated at school. Parents in nine schools were asked to report prior vaccination against influenza and influenza-like illness (ILI) of their children and other household members. Rate reduction was defined as [(ILI among unvaccinated) - (ILI among vaccinated)] / (ILI among vaccinated) (%). RESULTS: Of 527 participants, 359 (68.1%) were unvaccinated and 168 (31.9%) vaccinated. Unvaccinated children reported more ILI compared with vaccinated children (19.5% vs. 7.7%), yielding a rate reduction of 60.5%. Unvaccinated children also had a greater number of physicians' visits and missed school days (35.7% vs. 14.9 and 42.9% vs. 25.6%, respectively). The rate of ILI among household members of unvaccinated children was 34.5%, compared with 25.0% among household members of vaccinated children. The vaccinated cohort (defined as all children in second grade) reported less ILI compared with the unvaccinated cohort (defined as all children in third grade), with a rate reduction of 44.6%. Pupils of the unvaccinated cohort were more likely to miss school days (42.1% vs. 32.0%, respectively), and a higher rate of ILI was reported among household members of the unvaccinated cohort (35.4% vs. 27.3%, respectively). CONCLUSION: Influenza vaccine administered in school setting reduced ILI among the vaccinated cohort and their household members by 60.5 and 27.5%, respectively, compared with the unvaccinated cohort. Expansion of the vaccination program in a school setting increased the public health benefit of influenza vaccines among both school children and their household members.

The role of children in the spread of COVID-19: Using household data from Bnei Brak, Israel, to estimate the relative susceptibility and infectivity of children.

One of the significant unanswered questions about COVID-19 epidemiology relates to the role of children in transmission. This study uses data on infections within households in order to estimate the susceptibility and infectivity of children compared to those of adults. The data were collected from households in the city of Bnei Brak, Israel, in which all household members were tested for COVID-19 using PCR (637 households, average household size of 5.3). In addition, serological tests were performed on a subset of the individuals in the study. Inspection of the PCR data shows that children are less likely to be tested positive compared to adults (25% of children positive over all households, 44% of adults positive over all households, excluding index cases), and the chance of being positive increases with age. Analysis of joint PCR/serological data shows that there is under-detection of infections in the PCR testing, which is more substantial in children. However, the differences in detection rates are not sufficient to account for the differences in PCR positive rates in the two age groups. To estimate relative transmission parameters, we employ a discrete stochastic model of the spread of infection within a household, allowing for susceptibility and infectivity parameters to differ among children and adults. The model is fitted to the household data using a simulated maximum likelihood approach. To adjust parameter estimates for under-detection of infections in the PCR results, we employ a multiple imputation procedure using estimates of under-detection in children and adults, based on the available serological data. We estimate that the susceptibility of children (under 20 years old) is 43% (95% CI: [31%, 55%]) of the susceptibility of adults. The infectivity of children was estimated to be 63% (95% CI: [37%, 88%]) relative to that of adults.

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.

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.

Attitudes of Israeli medical students towards the medical treatment of uninsured migrants.

BACKGROUND: Undocumented migration to developed countries poses practical concerns, as migrants are not medically insured. This cross-sectional study aims to appraise the attitudes of Israeli medical students towards the uninsured migrant population. METHODS: Participants from five medical schools in Israel completed anonymous questionnaires in Hebrew, based on the "Medical Students' Attitudes Toward the Underserved" (MSATU), which assessed students' attitudes regarding the professional responsibility and societal expectations towards the migrants. It also evaluated students' views of the migrants as eligible for expensive medical procedures. RESULTS: A total of 891 students completed the survey with a median age of 28 years. The majority were Jews (N = 816, 91.6%) and singles (N = 681, 68.5%). Participants in the pre-clinical years were likely to be female and unmarried compared to those in clinical training. They also demonstrated higher scores on professional responsibilities and societal expectations than students in clinical training, but no significant differences were found in their views on expensive medical services. Students of minorities (non-Jews and migrants) scored higher on professional responsibilities and societal expectations. The scores for professional responsibilities and societal expectations decreased as students progressed in their medical training (Spearman coefficient p = 0.04 and p = 0.01, respectively). This trend was more apparent in males rather than females. CONCLUSION: MSATU scores declined as students progressed through medical school, with females maintaining more favorable attitudes than males. Medical schools should attempt to maintain the enthusiasm and idealism that students possess as they enter medical training and provide clinical experience with migrant populations that allows for cross-cultural communication.

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 human leptospirosis linked to contaminated water bodies in Northern Israel, June to August 2018.

We report preliminary findings of a large outbreak of human leptospirosis with 36 confirmed/probable and 583 suspected cases from June-August 2018, linked to contaminated water bodies in Northern Israel. There was a travel-associated case in Germany; additional cases are being investigated in other countries. The presumed chain of transmission, implicating wild boar and cattle, raises multiple challenges for risk assessment, risk management and risk communication currently being addressed by a public health response team.

Heterosexual men who purchase sex and attended an STI clinic in Israel: characteristics and sexual behavior.

BACKGROUND: Commercial sex shares a role in HIV and sexually transmitted infections (STI) transmission. Men who pay for sex (MPS) may transmit HIV/STI to other populations which are low-risk. This study aimed to test our hypothesis that MPS engage in high-risk sexual behaviors associated with HIV/STI transmission more so than non-MPS. METHODS: This cross-sectional study included heterosexual men who attended an STI clinic between 2003 and 2010. Demographic, clinical, behavioral and laboratory data were compared between MPS and non-MPS to identify factors associated with high-risk sexual behavior and STI-burden. RESULTS: Of the first visits of 6156 heterosexual men who attended the STI-clinic during the study period, 1649 (26.7%) were MPS. MPS were more commonly older, married and non-Israeli born compared with non-MPS. MPS were more likely to engage in risk-behaviors associated with HIV/STI-transmission, including a greater number of lifetime sexual partners, substance use and previous STI diagnoses. Determinants associated with STI-diagnoses at the current visit included being non-Israeli born, presenting with STI symptoms, reporting a greater number of lifetime sexual partners and having sexual encounters with non-Israeli individuals. CONCLUSIONS: Approximately 25% of all men who attended the clinic were MPS. They were more likely to engage in risk-behaviors associated with HIV/STI transmission compared to non-MPS. These findings highlight the need to establish interventions for MPS that both continue to encourage condom use and address the potential perils pertaining to risky sexual behaviors.