[Optimal fluoride level in drinking water and public health].

Water fluoridation is a safe, efficient, and well-proven way of preventing dental decay in the community. In countries such as Israel, where dental care is not covered by the national insurance law, this has an important role in reducing social inequalities in health care. For toddlers and children, water fluoridation is the only way of promoting dental health without a need for regular visits to dental clinics, and without regard to parent awareness and motivation. The other methods of fluoride supplementation do not succeed in reaching the level of safety and cost-efficiency of water fluoridation, and their use is successful only among upper socio-economic classes. Water fluoridation has been defined by the US CDC as one of the main achievements in health care during the 20th century. In spite of the legal difficulties raised by various activist groups, the use of water fluoridation is growing steadily among developed as well as third world countries. The Israeli bylaw of national water fluoridation that is in effect will enable the safe improvement of the overall dental health status of the population at an extremely low cost.

[Exposure to radon gas at schools, Cohen's paradox and public health policy].

Finding Radon levels above the legal threshold in schools and private homes has become an highly publicized problem in Israel, due to the rising awareness of the public to environmental matters and its influence on human health. However in the last decade a growing number of research reports have put serious doubts upon the validity of the scientific model used for assessing the health risk due to exposure to low intensity ionising radiation. The present paper surveys the development of the critics of the Linear No-Threshold Hypothesis (LNTH) that was used up to now as a scientific basis for public health policy in this field. The implications for the Israeli population and Health authorities are discussed. In the authors' opinion, controlling radon levels is an aim by itself, irrespectively of its causal relationship to lung cancer, and is part of a wider policy of maintaining the background exposure to ionizing radiation of the Israeli population to the lowest possible level. However its role in prevention of lung cancer morbidity and mortality is neglectable, and efforts must concentrate upon prevention and cessation of smoking. Smoking remains the most important preventable cause of lung cancer, and potentialize the effects of all other possible carcinogens.

[West Nile fever in Israel--past and present].

The present outbreak of West Nile Fever in Israel, which started in July 2000, caused some amount of panic among the Israeli public and interest among the medical, environmental and veterinary professions. The authors review the relevant literature and demonstrate that this disease has been recorded in the last 50 years in Israel and is highly endemic in this country. The last outbreak in the late summer and autumn of the year 2000 was unique in its size: 429 serological proved cases and 29 deaths. However, the current sudden rise in the number of cases, unknown in preceding years, is due to a combination of a few factors: high incidence of the disease among migrating wild and domestic birds, presence of mosquitoes near susceptible human populations, awareness among the medical profession and recent introduction of a specific serological diagnosis test in only one central laboratory and its present availability to Israeli physicians. The authors review the past and present history of West Nile Fever in Israel. They discuss the implications of this outbreak on public health policy and its prevention, stressing the need for cooperation between health, environmental and veterinary services and local authorities in order to prevent the next outbreak.

Altered sensitivity to retinoid-induced apoptosis associated with changes in the subcellular distribution of Bcl-2.

In the acute promyelocytic leukemia cell line NB4, Bcl-2 downregulation occurred as a late event of retinoid-induced differentiation. In the maturation-resistant NB4-R1 subclone, retinoids failed to downregulate Bcl-2 even in the situation of apoptosis massively induced by pan-agonists and RXR-selective agonists. We observed that NB4 and NB4-R1 cells differed with respect to the intracellular localization of Bcl-2 which showed a perinuclear localization in NB4-R1 cells, while Bax was broadly expressed in the cytoplasm and to only a minor extent in the perinuclear area. Therefore, the distinct intracellular localization of Bcl-2 and Bax was in general nonoverlapping. Bcl-2 remained massively expressed until cell disruption. Bax was not significantly upregulated in cells committed to death. However, Bax localization changed from a diffuse pattern to concentrate in few specific cytoplasmic area at a stage preceding the formation of apoptotic bodies. A human Bcl-2 transgene was transiently overexpressed in NB4-R1 cells which showed increased resistance to apoptosis induced by retinoids. Stably transfected clones of NB4-R1 cells showed an increased expression of Bcl-2 and a marked resistance to apoptosis. Interestingly, the overexpression of Bcl-2 restored a pattern of uniform Bcl-2 labeling in the cytoplasm and, remarkably, the colocalization of Bcl-2 with Bax. This work demonstrates that the ability of retinoid-induced cells to undergo apoptosis depends on the level of expression and the functional interaction between Bcl-2 and Bax.

Medical aspects of the Iraqi missile attacks on Israel.

During the period 18 January-28 February 1991, a total of 39 Iraqi modified Scud missiles landed in Israel, most of them in the densely populated Tel Aviv area. There were 23 missile attack alerts. These attacks caused 1,059 cases of injury; there were two deaths and 232 patients were admitted to emergency rooms for injuries directly related to the explosions, only one of which was severe. A survey among 91 of the injured showed that 46.6% of the wounds were caused by glass splinters, 31.1% were blunt contusions, and 22.2% were acute psychological reactions. No case of blast injury was reported. Inappropriate injection of atropine was reported in 230 cases. Acute anxiety was the reason for admission of 544 patients to emergency rooms. Another 40 patients sustained various traumas while rushing to the sealed room. The relatively low number of injured people is striking in view of the density of population in the areas hit. Various explanations are discussed.

Seasonality and long-term trends of pediculosis capitis and pubis in a young adult population.

Little is known about seasonality and long-term trends in the incidence of pediculoses. Such information would help both public health workers and clinicians in the prevention and management of the problem. In the Israel Defence Forces the pediculoses are individually notifiable, and this provides a unique database for the study of this subject. The incidence of head louse infestation increased from 5.2 per 1000 in 1977 to 18.1 per 1000 in 1979, and then declined to 3.6 per 1000 in 1987. The incidence was higher in the warmer months. Pubic louse infestation increased from 7 per 1000 in 1977 to 14.9 per 1000 in 1983, and then declined to 4.6 per 1000 in 1987. The incidence was higher in the cooler months. Possible causes of the seasonality and long-term trends are discussed.

Sociodemographic factors associated with Pediculosis capitis and pubis among young adults in the Israel Defense Forces.

While socioeconomic factors have been found to be important in the incidence of head lice (Pediculosis capitis) infestation, most reports pertain to children. Furthermore, it is not clear whether similar factors are correlated with infestation with pubic lice (Phthirus pubis). We examined the association of two measures of socioeconomic status with each condition in a random sample of 500 notifications of each condition in the Israel Defense Forces. Since head lice were predominantly reported in females, and pubic lice predominantly in males, the analyses for head lice were restricted to females (474 cases) and those for pubic lice to males (481 cases). A significant negative association was found between both the number of years of formal education and a measure of socioeconomic status with infestation with both head and pubic lice. These findings suggest that among adults, both types of infestation are more common in the lower socioeconomic groups, and this should be taken into account when designing public health campaigns to control these problems.

Recent decline in gonorrhea incidence in Israel: possible association with the AIDS pandemic.

The effect of the AIDS pandemic on the sexual behavior of the general population has not been clearly established. Since trends in the incidence of other sexually transmitted diseases may be a good marker of such behavioral changes, gonorrhea incidence in the civilian and military populations in Israel was examined during the period 1963-87. In the civilian population, the rates were relatively stable until 1967, when they increased to a peak in 1970 and then declined to the earlier levels. In 1982 a further decline began, which accelerated considerably in 1986 when the rates declined by 38%. During 1987 the decline was even more dramatic, with a drop of 60% compared with the rate of the previous year. A similar trend has been noted in the military population. The recent sharp decline in gonorrhea incidence may be related, at least partly, to a change in sexual behavior associated with the fear of AIDS. If so, its magnitude suggests that such changes have not been restricted to high-risk groups.

PIP: The effect of the AIDS pandemic on the sexual behavior of the general population has not been clearly established. Since trends in the incidence of other sexually transmitted diseases may be a good marker of such behavioral changes, gonorrhea incidence in the civilian and military populations in Israel was examined during the period 1963-87. Among the civilian population, the rates were relatively stable until 1967, when they increased to a peak in 1970 and then declined to earlier levels. In 1982, a further decline began, which accelerated considerably in 1986 when rates declined by 38%. During 1987, the decline was even more dramatic, with a drop of 60% compared with the rate from the previous year. A similar trend has been noted in the military population. The recent sharp decline in gonorrhea incidence may be related, at least in part to a change in sexual behavior associated with the fear of AIDS. If so, its magnitude suggests that such changes have not been restricted to high-risk groups.