Epidemiological analysis of tuberculosis treatment outcome as a tool for changing TB control policy in Israel

BACKGROUND

Sensing an inadequacy of tuberculosis control due to an influx of TB associated with immigration, we analyzed TB treatment outcome in Israel by population groups.

OBJECTIVES

To provide an epidemiological basis necessary for any new national TB control policy, and to bring it to the attention of the medical profession in Israel and abroad since its results led to a change in Israel's TB control policy.

METHODS

We reviewed all TB cases notified during the period 1990 to September 1992. "New cases" (820 cases, 93.5%) and "re-treatment cases" (57 cases, 6.5%) were analyzed according to three mutually exclusive groups: "successful outcome," "death," and "potentially unsatisfactory outcome" (according to WHO/IUATLD definitions).

RESULTS

Of 820 "new cases," 26.6% had a "satisfactory outcome," 68.5% had a "potentially unsatisfactory outcome" and 4.9% died; compared to 47.4%, 45.6% and 7% among 57 "re-treatment cases," respectively. Using logistic regression analysis, outcome was associated with the district health office (P < 0.0001), the TB "experience" of the notifying clinic (P < 0.0001), and the form of TB (P = 0.02). No significant relationships were obtained for population groups, gender and age, interval between arrival in Israel and TB notification, and bacteriological results.

CONCLUSIONS

Non-supervised TB treatment resulted in poor outcomes regardless of population groups. Better outcomes occurred in the larger TB clinics. Therefore, in addition to measures such as adequate drug supplies, reorganization of TB laboratories and training of TB personnel, we recommend the "directly observed treatment short-course" for all cases as well as reducing the number of treatment centers thereby increasing their case load.

The changing epidemiology of viral hepatitis A in Israel

BACKGROUND

Between 1970 and 1979, there was an increase in the incidence of viral hepatitis in Israel with a shift of peak incidence to an older age in the Jewish population, followed by a declining trend during the early 1980s. In July 1999 universal immunization of infants against hepatitis A was introduced.

OBJECTIVE

To evaluate the chan-ges in the epidemiology of viral hepatitis A in Israel during the past decade.

METHODS

Viral hepatitis is a notifiable disease in Israel and cases are reported to the regional health offices, which in turn provide summary reports to the Ministry of Health's Department of Epidemiology. The data in this study were derived from the summary reports and from results of seroprevalence studies.

RESULTS

Following the increase in the incidence of reported viral hepatitis (mainly due to type A) between 1970 and 1979, the rates then stabilized and around 1984 began to decline until 1992. Since then there has been a slight increase. Whereas until 1987 the rates were consistently higher in the Jewish population, since then they are higher in the Arab population. The shift in the peak age-specific incidence from the 1-4 to the 5-9 year age group observed in the Jewish population around 1970 occurred 20 years later in the Arab population. The previously described seasonality is no longer evident. Recent seroprevalence studies indicate that by age 18 years only about 30-40% of the Jewish population have anti-hepatitis A antibodies.

CONCLUSIONS

The decline in the incidence of hepatitis probably reflects the changing socioeconomic condition occurring at different times in the two major population groups. Since hepatitis A accounts for almost all the acute viral hepatitis in Israel, the universal vaccination of infants introduced in 1999 should substantially lower the morbidity within the next few years.

Cost-benefit analysis of a nationwide infant immunization programme against hepatitis A in an area of intermediate endemicity

BACKGROUND/AIMS

The availability of safe and effective Hepatitis A vaccines prompts an evaluation of a nationwide infant vaccination campaign to supplement strategies aimed at high-risk groups such as travellers and military personnel.

METHODS

A spreadsheet model was used to estimate costs and benefits of a nationwide infant immunization programme against Hepatitis A for the period from 1997-2014 in Israel.

RESULTS

Immunizing all one year olds in Israel from 1997-2014 would for a cost of $32.0 million to the health services and $42.1 million to society (including $10.1 million lost work and transport costs), reduce the number of cases of Hepatitis A during the next 45 years from 181,000 to 47,000. This would save $57.5 million in health service resources alone, $32.0 million in averted work absences and transport costs in addition to a further $17.0 million in averted premature mortality costs. The health service, resource and societal benefit:cost ratios are 1.80:1, 2.13:1 and 2.54:1, respectively.

CONCLUSIONS

The recent adoption of a nationwide infant HAV immunisation policy in Israel is both medically and economically justifiable.

Measles control in Israel: a decade of the two-dose policy

BACKGROUND AND METHODS

The introduction of routine measles immunization in Israel in 1967 was followed by a 95% reduction in reported measles incidence. In 1990, a second measles immunization dose was instituted, and up until the end of 1999, 16 birth cohorts were offered the second dose. We present here changes in reported measles incidence in Israel following institution of the two-dose policy.

RESULTS

First-dose coverage is 94%, and coverage for the second school-based dose exceeds 95%. A further 90% reduction in measles incidence has been observed and, following a modest national outbreak in 1994, measles incidence for 1995-99 stands at less than 3/100,000/year.

CONCLUSIONS

Since measles is highly contagious, very high immunization coverage rates will be required to preserve these accomplishments, and measles elimination is still years away, but there is tentative evidence that measles containment is at hand. Even greater measles control can be anticipated as vaccine immunogenicity improves and successive cohorts of children come under the 2-dose regimen.

[Introduction of routine hepatitis A immunization in Israel--the first in the world]

Notification of hepatitis A, which is endemic in Israel, has been compulsory since the establishment of the State. From 1992-98 an average of 2,600 cases were reported annually. Many infections are asymptomatic and mild, especially in children. In general, severity increases with age; in Western countries the case fatality rate is 1.5/1,000 among children less than 5 years old and 27/1,000 among those over 50. Until 1987 incidence in Israel was higher in Jews than in non-Jews, but since 1988 incidence has been about 50% higher in non-Jews. Among Jews highest age specific rates shifted from children 1-4 years old to children 5-9 years old in 1970, and in non-Jews in 1989. Improved sanitary conditions and personal hygiene have reduced very early childhood exposure and hence increased the proportion of susceptible older children and adults, in whom symptomatic disease is more prevalent. Israel is the first country in the world to include hepatitis A vaccine in its routine immunization schedule. The vaccine is given in 2 doses: at 18 months and 24-30 months of age, and there will be epidemiologic and serologic follow-up. A significant decrease in hepatitis A morbidity is expected in small children within 5 years. The percentage of reported cases in older children and in adults is expected to increase, although the absolute incidence among these groups will decrease.

The control of mumps in Israel

BACKGROUND

Measles-mumps-rubella (MMR) vaccine replaced monovalent measles vaccine in the routine childhood vaccination schedule in Israel in December 1988, primarily to achieve the elimination of the congenital rubella syndrome. In this observational study, we report on changes in reported mumps incidence in Israel from the time of the introduction of MMR vaccine until the end of 1998.

METHODS

The report is based upon passive national surveillance of mumps incidence, which has been notifiable in Israel since 1977.

RESULTS

Reported mumps incidence in Israel is now less than 2% the pre-vaccine incidence.

CONCLUSIONS

In the decade since the introduction of routine mumps vaccination in 1-year-olds in Israel, mumps control has been achieved. Although small outbreaks occur and may continue to occur in future years, because of under-vaccination of children, primary vaccine failure and waning immunity, it can tentatively be said that mumps is no longer a public health problem in Israel.

Clinical manifestations of Bordetella pertussis infection in immunized children and young adults

STUDY OBJECTIVES

The incidence and prevalence of pertussis in adults have increased in recent years. It has been shown that previously immunized adults and adolescents are the main sources of transmission of Bordetella pertussis. The aim of this study was to describe the clinical presentation and the clinical course of pertussis in children and young adults who were immunized previously against B pertussis.

DESIGN

Retrospective study.

SUBJECTS

Children and young adults who were reported by local physicians to the Department of Epidemiology in the Israeli Ministry of Health with serologically confirmed pertussis and who were immunized previously were included. Information sought included personal data, epidemiologic data, signs and symptoms, laboratory results, initial diagnosis, and treatment.

RESULTS

In the 95 previously immunized patients with serologically confirmed pertussis (mean age [+/- SD], 8.9 +/- 4.4 years old; range, 5 to 30 years old), the mean duration from onset of symptoms until the final diagnosis of pertussis was 23 +/- 15 days. The disease was usually atypical and generally mild. All the described patients had cough, usually prolonged, lasting 4 +/- 3.6 weeks. Only 6% had the classic whoop. The mean WBC count was 8.7 +/- 2.6 cells/mm6, and the lymphocyte count was 40 +/- 12%. Two patients were admitted to the hospital for severe pneumonia. Among the reported cases, the proportion of patients between the ages of 10 and 45 years increased from 6.5% during the period from 1971 to 1980, to 26% during the period from 1980 to 1990, and to 38% during a 1989 outbreak.

CONCLUSIONS

Pertussis in previously immunized individuals is usually characterized by an atypical and relatively mild clinical course. Patients suffer mainly from a prolonged and persistent cough. Early diagnosis may lead to prompt administration of therapy. Prophylaxis of exposed persons might be effective in decreasing both severity and transmission of the disease.

Screening for thyroid abnormalities among immigrants to Israel from the former USSR

The exposure of some former Soviet citizens to radiation following the 1986 Chernobyl disaster has raised the question of the need to enroll these individuals in screening programs for thyroid abnormalities upon their immigration to Israel. Since screening programs have many drawbacks, and screening for thyroid disease has never been shown to decrease mortality or to improve survival, we are of the opinion that the establishment of thyroid screening programs will do more harm than good. The timely diagnosis of the very small excess in benign and malignant thyroid disease to be anticipated among the immigrants can be achieved in the community by the primary care physician armed with specific knowledge of the risks and the initial diagnostic approaches to suspected thyroid disease as well as information on the availability of specialist backup.

International epidemiological and microbiological study of outbreak of Salmonella agona infection from a ready to eat savoury snack--II: Israel

OBJECTIVES

To explain an increase in the incidence of salmonellosis caused by Salmonella agona in Israel between October 1994 and January 1995 in the light of an outbreak of S agona phage type 15 infection in England and Wales caused by consumption of a ready to eat savoury snack produced in Israel.

DESIGN

Epidemiology of S agona in 1994-5 was analysed and two consecutive, case-control studies of 32 and 26 case-control pairs were performed. Phage typing and molecular methods were used to characterise strains of S agona isolated from cases and samples of the snack in Israel and England and Wales.

RESULTS

The increase in the incidence of S agona between October 1994 and January 1995 was countrywide. Cases of infection with group B salmonella increased from 60% to 80% in children under 5 years old. In both case-control studies, cases consumed more of the snack than did controls (4.25 v 2.94 packets per week in the first study (P = 0.086) and 4.04 v 2.37 packets per week in the second study (P = 0.034)). When the two studies were combined there was a significant dose-response relation for the number of packets consumed weekly. Compared with consumption of less than two packets, the odds ratio was 1.43 for between two and six packets and 3.37 for seven or more packets (chi 2 for trend = 5.27, P = 0.02) S agona phage type 15 was isolated from a packet of the snack sold in Israel, and the strain was identical with those isolated from packets and cases in Israel and England and Wales.

CONCLUSIONS

This outbreak of S agona was caused by the contamination of a snack produced in Israel. Even under modern operating conditions, large, widespread international outbreaks of foodborne disease can occur. The success of this investigation resulted from excellent international collaboration between public health authorities.

Malaria Imported by Travelers: The Israeli Experience

Indigenous malaria has been successfully eradicated in North America, Europe, and a few other previously endemic locations. Extensive antimalarial programs, improvement of health care services, and advances in socioeconomic development have all contributed to one of the most significant achievements in public health of the 20th century.1 Nevertheless, a new malaria transmission pattern is increasingly seen in these areas nowadays. The constantly mounting movement of travelers from developed countries to the tropics and the affluent immigration to the industrialized world from countries where malaria has remained endemic are responsible for the emergence of imported malaria.2 Most physicians who studied medicine in developed countries, although familiar with the classic presentation of the disease, have rarely seen a single case of malaria during training and believe that it is an exotic illness existing elsewhere. It is important therefore to characterize the demographic and clinical features of imported malaria, which is practically the only malaria now seen in the industrialized world, and to make it more familiar to health care providers. This need is further emphasized by the emerging problem of drug-resistant malaria, which may be atypical in patients who had received inappropriate prophylaxis. In Israel malaria is almost exclusively an imported disease. It occurs in Israelis who visit or work in endemic areas and in immigrants, invariably from Ethiopia. The majority of Ethiopian immigrants arrived in two waves in 1985 and 1991 and do not represent an ongoing malaria problem.3 The features of the disease in this population were extensively reported elsewhere.3,4 In the present report we examine the characteristics of malaria imported to Israel by travelers.

Decay of maternally derived measles antibody in a highly vaccinated population in southern Israel

The introduction of live attenuated measles vaccine in Israel during 1967 dramatically decreased the incidence of measles. However, cases still occur in periodic outbreaks and epidemics, with an increasing proportion of infants and children younger than 2 years of age. We examined the decay of maternally derived measles antibody during the first year of life in the Jewish population of Israel which represents a highly vaccinated population with immunization rates exceeding 90%. We used sera of healthy full term infants born in 1988 and 1989. Fifty specimens for each of the following age groups were used: 0 (cord blood), 2, 4, 6, 7 and 12 months. Three assays for each specimen were used: enzyme-linked immunosorbent assay (ELISA); hemagglutination-inhibition test (HI); and neutralization test (NT). Good correlation among all 3 tests was found. All cord blood specimens were positive by at least 2 assays. Seropositivity rates declined rapidly with age. Fifty percent of all 4-month-old infants and < 30% of all 6-month-old infants were positive by 1 test or more; at 12 months of age none of the tested specimens was positive by HI or NT and only 1 of 50 infants was positive by ELISA. In infants younger than 6 months of age, 5 (22%) of 23 specimens negative both by ELISA and by HI were positive by NT, but in 6-month-olds, only 2 (7%) of 28 negative by ELISA and HI were positive by NT, and in 12-month-olds none was positive. The results from southern Israel are similar to those obtained in North America and provide evidence that infants older than 6 months of age in a well-immunized population may be poorly protected against measles. On the basis of this information and epidemiologic data, the Israel Ministry of Health has recommended lowering the immunization age for measles, mumps and rubella from 15 months to 12 months.

Absence of an association between rubella vaccination and arthritis in underimmune postpartum women

In a double-blind historical cohort study, 485 underimmune women who received rubella vaccine post-partum during 1985-1990 and 493 controls matched for age, place of residence and date of delivery were queried by phone concerning joint complaints following the pregnancy in question. Those reporting joint symptoms were invited for a personal interview at which joint symptoms and dates of their occurrence were explored in detail. Nineteen women in the vaccinated group (3.9%) and 16 from the control group (3.2%) were judged to have had joint symptoms compatible with the study definition of arthritis. The difference was not statistically significant. Thus, we were unable to find evidence for an association between rubella vaccination of underimmune adult women vaccinated post-partum and the subsequent development of arthritis. Rubella vaccine should continue to be used to immunize susceptible adult women against rubella in order to further the goal of elimination of the congenital rubella syndrome.

Prevalence of HBsAg carriers in pregnant women in Jerusalem: risk for horizontal transmission to family members

A prospective study was undertaken in Jerusalem to quantitate the HBsAg prevalence rate in pregnant women, to assess the effect of ethnic origin on HBsAg prevalence rates, and to determine the impact of HBsAg carrier state on hepatitis B virus horizontal transmission in the family. Of the 6,572 women screened at the time of delivery, 42 (0.64%) were found to be HBsAg positive. Although the percentage of Moslem women was 3.4% of the total study population, they accounted for 23.8% of the HBsAg positive mothers. This resulted in a prevalence rate of 4.48% as compared to only 0.5% in the Jewish population (P < 0.01). Nine percent of siblings born to HBsAg positive mothers and 29% of the husbands were found to be horizontally infected.

A seroprevalence study of herpes virus type 2 infection in Israeli women: implications for routine screening

The aim of the study was to obtain data on the prevalence of herpes simplex virus type 2 (HSV-2) in selected populations of women and to identify groups that might benefit from routine prenatal screening. The prospective seroprevalence study was performed in 1,921 women in Israel during the period 1986-90. Four different population groups of women 17-60 years old were included. Groups 1 and 2 comprised 1,214 healthy female government employees and kibbutz and moshav residents, and Groups 3 and 4 comprised 707 Jewish and non-Jewish women with gynecological complaints. HSV-2 antibody in the sera were studied by the microneutralization method. In the healthy women (groups 1 and 2), the prevalence of antibodies to HSV-2 was 2-3%. Genital HSV-2 asymptomatic shedding was 1%. In the women with gynecological complaints (groups 3 and 4) the prevalence of antibodies to HSV-2 was 10% in Jewish and 16% in non-Jewish women. These data support the conclusion that there is no justification for routine prenatal HSV-2 screening in Israel in a healthy female population.

The epidemiology of adult AIDS and HIV infection in Israel

Between 1980 and 1992, 227 AIDS cases and 1,010 HIV seropositives were diagnosed in Israel, 222 AIDS cases and 965 seropositives occurring in persons aged 13 years and older. Among the AIDS cases, the predominant risk groups were male homo/bisexuals, intravenous drug abusers (IVDAs) and hemophiliacs. Among the seropositives, the predominant risk group comprised men and women originating in countries characterized by pattern II transmission; however, among nonimmigrants, male homo/bisexuals, IVDAs and hemophiliacs predominated. In recent years, there has been a gradual fall in the number of new seropositives among homosexuals and drug abusers, and the appearance of seropositive hemophiliacs has ceased. The spread of HIV infection in the indigenous heterosexual population has been negligible.

[Epidemiology of Hansen's disease in Israel]

There are currently 200 patients with Hansen's disease in Israel who are being followed by the Hansen's Disease Government Hospital and the Ministry of Health (prevalence 4.4/100,000). Most of them immigrated from countries where the disease is endemic. Dermatological findings dominated the initial clinical picture, although 5% of patients are asymptomatic contacts of known cases. Age at onset of disease was less than 20 years in 1/4 of the cases. The incidence in Israel is falling: 0.4/100,000 in 1985-89 compared to 3.6/100,000 in 1950-54. Neurologic and dermatologic findings in an immigrant of any age originating from countries where Hansen's disease is endemic, should prompt appropriate diagnostic evaluation, even years after immigration to Israel. Contacts of known cases of Hansen's disease should be aggressively screened, even if asymptomatic.

Forty years of meningococcal disease in Israel: 1951-1990

Meningococcal disease accounts for approximately 20% of cases of bacterial meningitis in Israel. During the period 1951-1990, the annual incidence of meningococcal disease rarely exceeded two cases per 100,000 persons and was generally higher among non-Jews (largely the Arab population) than among Jews; there were some notable peaks of disease activity during 1963-1967, 1975, and 1987-1988. The highest incidence was among infants and young children, with a slight male predominance. The main period of disease activity was from January to April, but an unusual secondary peak in July coincided with the onset of peak summer temperatures. Monthly disease frequencies were significantly correlated with relative humidity. Incidence rates varied between regions and were lower in cities than in smaller settlements. Overall case-fatality rates decreased to approximately 11% for the period 1981-1990. Outbreaks were infrequent and tended to be small. Meningococci of serogroup B have dominated since the mid-1970s. Group A meningococci were isolated significantly more commonly from Arabs (26.26%) than from Jews (1.03%; P < .000001). The frequency with which group A organisms occurred among clinical isolates appeared to follow a more or less cyclical pattern.

Imported malaria from Ethiopia--end of an era?

The immigration of Ethiopian Jews to Israel in the 1980s resulted in the importation of over 2,000 cases of malaria, a major challenge to clinicians and public health officials alike. In contrast, in the massive airlift from Ethiopia in May 1991 and in the sporadic immigration that followed it, malaria prevalence was extremely low, reflecting the routing of the more recent immigrants through nonendemic areas. The dramatic fall in the appearance of new imported malaria cases should not lead to complacency, however, as malaria may still appear in Ethiopians and other immigrants as well as in Israelis returning from regions of the world where the disease is still highly prevalent. A corollary of this caveat is that vigilance in finding and eliminating Anopheles breeding places in Israel must not be allowed to falter.

Multiphasic screening: an idea whose time has passed

The theory of screening for preclinical disease requires that early diagnosis and treatment will lead to an outcome which is more favorable than that resulting when treatment is initiated after symptoms appear. In practice, this requirement is met for a surprisingly small number of diseases. Early detection components of "health packages" must be developed, therefore, strictly on the basis of proven effectiveness. Existing programs should be revised in accordance with international guidelines, and adapted as needed to the local incidence and prevalence of disease and anticipated population compliance, so that the maximum benefit of early detection can be realized and the numerous hazards of screening avoided.

Mortality in Israel during the Persian Gulf war--initial observations

During the 6-week-long 1991 Persian Gulf war, in which the civilian population was subjected to 18 separate missile attacks and the constant threat of nonconventional warfare, crude mortality rates in Israel were no higher than in the previous decade. Although the results are preliminary and need to undergo more sophisticated epidemiologic analysis, it appears that our population was able to tolerate the subacute period of psychological stress without excess mortality.

The epidemiology of echinococcosis in Israel

Shifts in population and employment patterns in Israel since 1948 have been accompanied by profound changes in the distribution of echinococcal disease. Formerly, it was most commonly imported with the mass immigration of Jews after 1948 from the Arab countries of North Africa and Asia Minor, and appeared to be relatively uncommon in Israel-born Jews and Arabs. In 1980 the disease was made notifiable, and this paper presents a review of the years 1981-1989. The prevalence pattern that prevailed after the end of mass immigration has reversed so that cases are now twice as common in Arabs as in Jews. Among the Arabs the disease appears most commonly in the north of the country, especially among the Druze, less commonly among Christians and least in Muslims. We suggest that this prevalence pattern is related largely to home slaughter of sheep, to differing attitudes to dogs, and possibly also to the hunting of wild pig. Targetted education and better enforcement of existing regulations can lead to a reduction in disease.

Can decision analysis help in the management of giant hemangioma of the liver?

We explore the trade-off between the risk and expected benefits from resection of giant liver hemangioma (GLH), one larger than 4 cm in diameter. We searched the English-language literature for studies of the postoperative mortality after resection of GLH and of the outcome of expectantly treated patients. The results of the data synthesis showed an operative mortality of 1.5% (90% confidence intervals, 0.1-3.0%) and an early surgical morbidity of up to 13%. Mortality among the 37 reported cases with ruptured GLH was 78%. There were no cases of spontaneous or traumatic rupture of unresected GLH during a follow-up of a total of 282 patient years. The main source of ambiguity regarding the management of GLH is the uncertain risk of its rupture. Rough estimates of this risk based on published data suggest that surgical resection is not justified in asymptomatic GLH. Yet, although rare, rupture of GLH does occur with disastrous consequences. Future research may attempt to define patient subsets whose GLHs are at higher risk of rupture, and in whom preventive resection may improve survival.

Malaria in Israel: the Ethiopian connection

Over 2,000 cases of imported malaria were diagnosed in Israel in the last decade, the vast majority in immigrants from Ethiopia, making malaria a continuing public health problem of significance. In 1988, more than one- fifth of imported cases were caused by chloroquine-resistant Plasmodium falciparum. Since the Anopheles vector is still present in many areas of the country, it is necessary to detect and treat all cases quickly and effectively and to strengthen anti-malaria vector activities if local transmission is to be prevented. Despite massive and continuous importation of the disease, the Ministry of Health has had substantial success in the area of malaria control, through administration of presumptive treatment to Ethiopian immigrants, rapid diagnosis of imported cases and strict vector control.

Prevention strategy of hepatitis B virus infection among the Ethiopian community in Israel

Between 1980 and 1985, over 16,000 immigrants from Ethiopia, a population at high risk for hepatitis B virus (HBV) infection, arrived in Israel. The present study was designed to provide epidemiological information necessary for developing prevention strategies against HBV infection. Among the 144 subjects studied in an absorption center in Israel, only 32% had no detectable HBV markers and were therefore susceptible to infection. The prevalence rate of HBsAg was 19% compared with 42% for anti-HBs and 7.6% for anti-HBc alone. The percentage of subjects with no HBV marker decreased sharply with age, and there was similarly an age-linked increase in anti-HBs, indicating the importance of horizontal transmission in HBV infection. The distribution of HBV markers was similar in both sexes. Evidence of mild liver disease was found in only three subjects. All newborns and new arrivals less than 2 years of age in the Ethiopian community are vaccinated against HBV infection to prevent vertical and early horizontal transmission. The data obtained in our study suggest that this means of prevention of HBV infection is insufficient. We suggest that the vaccination of all children aged 2-7 without prevaccination screening, and the vaccination of children aged 8-18 found to be susceptible on anti-HBc screening, would substantially lower HBV transmission in this community.

Analysis of historical epidemiological data to guide intervention policy in the face of an infectious disease outbreak: poliomyelitis in Israel in 1988

During the 1988 outbreak of 15 cases of Type 1 poliomyelitis mainly among previously vaccinated young adults in Israel, there were conflicting views on the need for and timing of mass vaccination. Since there was a possibility that the initially localized outbreak may spread more widely, it was felt that an early decision on vaccination policy should be made. Public health officials were faced with varied interpretations of the existing data on the extent of the immune status of the population; some indicating that as many as 15% of young adults lacked immunity to the Type 1 virus. Two major questions posed were whether or not the outbreak was a purely localized event in a single subdistrict, and whether the seasonality of the disease would limit its spread. Based on historical data, probability analysis of three cases occurring outside the subdistrict at the time of the outbreak suggested more widespread dispersion of the virus. Further analysis indicated very limited seasonality of the disease in this region, suggesting that the onset of colder weather would have little impact on the spread of the virus. Careful analysis of the local epidemiology of the disease is an important tool for guiding urgent decisions on mass intervention policy in outbreak situations.

Four decades of shigellosis in Israel: epidemiology of a growing public health problem

Despite the improved standard of living in Israel, shigellosis remains a common disease. Examination of trends in the incidence of shigellosis in Israel between 1951 and 1987 showed a period of declining rates followed by an increase in the reported incidence beginning around 1969. This increase was mainly due to Shigella sonnei; rates of infection with Shigella flexneri remained relatively constant. Trends showed marked differences between age groups and between ethnic groups. In comparison, the rates in the United States--much lower than those in Israel--began to decline in the early 1950s and have remained low. The incidence in Israel is now about 20 times higher than that in the United States. Thus shigellosis remains a major and growing public health problem in Israel, a country that has enjoyed a dramatic improvement in basic sanitary services and infrastructure over the past few decades. This disturbing finding lends urgency to efforts to control the disease.

Measles in Israel, the West Bank, and Gaza: continuing incidence and the case for a new eradication strategy

Measles continues to occur in epidemic waves in Israel, Gaza, and the West Bank, causing morbidity and mortality. In Israel, immunization of infants against measles began in 1967, and 90% had been immunized by the mid-1980s. In Gaza and the West Bank, where immunization of infants against measles began in 1973 and 1976, respectively, the immunization rate reached 75% in the late 1970s and increased to greater than 90% in the 1980s. Measles epidemics, which previously had occurred in 5- to 7-year cycles, occurred every 2-4 years in the 1980s and affected individuals who were older than those affected in previous years. Israel's commitment to eradicating measles by 1992 will require a substantially expanded immunization program in comparison with the traditional program that requires immunization of infants alone. The benefits of several alternative immunization strategies considerably exceed their costs. A new, two-dose immunization will be needed as a minimal strategy, and a campaign for administering booster doses to school-aged children may be required as well to achieve control and eradication of measles. Measles is a serious but preventable public health problem; appropriate strategies must be devised by national and international public health officials to control the disease in developing and developed countries.

Prevalence of hereditary properdin, C7 and C8 deficiencies in patients with meningococcal infections

High incidence of hereditary complement (C) deficiencies was found among 101 patients who had a meningococcal disease. This study revealed 11 non-related patients with complete C deficiency: five deficient in C7, three in C8, two in properdin and one in C2. Additional C-deficient individuals, most of them with no history of severe bacterial infections, were detected in family studies. The C8-deficient patients were found to have a selective deficiency of the C8-beta subunit and a reduced expression of the alpha/gamma subunit. Only a few families with properdin deficiency have been described so far. However, it is likely that frequent analysis of the activity of the alternative C pathway in survivors of severe bacterial infections will disclose numerous properdin-deficient patients. All our C7-, C8- and properdin-deficient patients are Sephardic Jews whose families originated from Morocco, Yemen (C7 and C8 deficient) or Tunisia (properdin deficient). This and other findings indicate that the type of complement abnormality found in association with meningococcal infections varies with the ethnic origin of the patient.

Breast cancer screening in Tel Aviv

Optimal breast cancer screening includes both physical examination and mammography. In anticipation of the addition of routine mammographic screening to Israel's 25-year-old early breast cancer detection program, we examined the demographic characteristics of almost one thousand women attending a breast cancer screening examination in Tel Aviv for the first time. The specific objective of the survey was to see whether women attending screening were those who stood a good chance of benefiting from it. Only half the women were aged 40 or older, and there was a preponderance of women of Western origin. Almost half had a breast-related complaint at the time of the visit. Targeted public education and appropriate administrative measures are necessary to ensure that women who can benefit from screening attend screening clinics and that clinics are not filled to capacity by women needing diagnostic evaluation and followup rather than routine screening. Tel Aviv general practitioners appeared to be aware of the advantages of breast cancer screening.

Tetanus in Israel, Judea/Samaria and Gaza, 1968-89: progress and challenge

During the 1950s tetanus was a major public health concern in Israel, with incidence rates of up to 2/100,000 occurring predominantly among farmers and infants (tetanus neonatorum). These rates have declined considerably since then, with an average of 2 cases per year in recent years, and 5 cases in 1988. There has been a major decline in tetanus incidence in Judea/Samaria and Gaza, due to a successful vaccination program reaching over 90% of infants and schoolchildren and to educational programs. In Judea/Samaria and Gaza, prevention of tetanus neonatorum has improved as a result of the increasing number of hospital deliveries (now 62% in the West Bank and 80% in Gaza), and the widespread immunization of pregnant women and adolescent girls of childbearing age. Special efforts were given to the education of traditional birth attendants (dayas). Prevention of adult tetanus was achieved through immunization of high school students and laborers. Recent cases in all three areas are equally distributed between newborns and elderly persons. Because of the persistence of the incidence of tetanus, a review of Israel's immunization policy is indicated, focusing on high risk groups such as Bedouin women of childbearing age and the elderly.

Poliomyelitis outbreak in Israel in 1988: a report with two commentaries

An outbreak of 15 cases of paralytic poliomyelitis caused by type 1 poliovirus between July and October, 1988, prompted mass vaccination of the whole Israeli population under the age of 40 years. The focus of the outbreak (12 cases) was the Hadera subdistrict, one of two subdistricts where enhanced inactivated poliovaccine (eIPV) had been the only poliovaccine used for infants since 1982. 9 of the 15 victims were 15 years or older, and 9 had previously been immunised with at least three doses of oral poliovaccine (OPV). The authors are divided in their interpretation of the findings. One group considered that the likely causative factors were the greater susceptibility of young adults previously vaccinated with OPV as well as transmission of wild poliovirus to susceptible people by children with low gut immunity against poliovirus after vaccination with eIPV; they concluded that a vaccination programme combining eIPV with OPV is the best option for Israel in future. The other group believed the causative factors were exposure to contaminated sewage or close social contact within the epidemic foci, the presence of an epidemic strain differing from the wild Mahoney and Sabin type 1 vaccine strains, and the lower seropositivity rates and geometric mean titres of neutralising antibodies to the epidemic than to vaccine strains; they believe that eIPV is the means to achieve effective control of poliomyelitis in Israel.

Cost-benefit analysis of routine mumps and rubella vaccination for Israeli infants

Until January 1989, mumps vaccine was not routinely administered in Israel, and rubella immunization was restricted to adolescent girls. The theoretical effect of combined mumps-rubella vaccination was applied to a population consisting of a cohort of 1-year-old children followed for 13 years. Assuming 90% compliance and 95% vaccine efficacy, projected clinical cases of mumps, rubella, encephalitis and thrombocytopenia would be reduced by 4,144; 3,109; 13; and 1 respectively. We anticipate a benefit to cost ratio of between 1.17 and 1.77 for the program. Since only 10-20% of cases are reported, the true benefit to cost ratio is likely to be at least 5.85. The benefit to cost ratio based on health service benefits alone is between 0.34 and 0.52; however, after adjusting for under-reporting, benefits are expected to exceed costs. Expenditures for laboratory testing, a factor not previously considered in such an analysis, would be reduced by approximately $2,750 per year. These results justify the initiation in January 1989 of nationwide routine vaccination.