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T A Swartz

Publications and source records attributed to T A Swartz.

36 records · Page 2Linked to original sources
PubMed1978

Rubella in Jerusalem. 1. Seroepidemiologic findings in children born after the 1972 rubella epidemic.

Nine hundred and sixty-nine babies born after a severe rubella epidemic were tested at the age of eight months for the presence of hemagglutination inhibition antibodies to the disease. There were 208 (21.9%) seropositive babies with titers of greater than or equal to 1:16. Seven cases of congenital rubella were diagnosed at birth, 14 were confirmed by eight months and two babies, who were considered normal at the age of eight months, developed late signs of the disease. Less than 3% of the mothers of the seropositive babies had had clinically recognized rubella in pregnancy. If positive hemagglutination inhibition antibody to rubella accurately reflects congenitally acquired rubella infection, between 8.1 and 21.9% of the 969 babies had serologic evidence of the disease. For cases of congenital rubella diagnosed by the age of three years, the limits are between 8.9 and 23.7 per 1,000 live births for the risk of the disease at the height of the epidemic. Rubella vaccine was not available in Israel until after the 1972 epidemic, the effects of which justify the continued search for and immunization of seronegative women of childbearing age, in addition to routine immunization of young girls.

Adult↗
PubMed1978

Toxoplasmosis in Israel, 1970--73: evaluation of laboratory data.

Sera from 7,506 patients were examined for toxoplasma antibodies by the Sabin-Feldman dye test and the results were analyzed according to antibody level, by reason for referral, age and sex. Low antibody levels (less than 1:256) were found in 24.7% and significant titers (greater than or equal to 1:256), in 9.96%. The highest prevalence of significant antibody titers was in patients with lymphadenopathy (15.4%). The prevalence of significant titers was high in the age range of 5 to 19 years, whereas the prevalence of low titers rose with age. Toxoplasma antibodies were found in 29% of a control group of 554 apparently healthy adult women, but only in 2.7% was the titer significant.

Adolescent↗
PubMed1976

An extensive rubella epidemic in Israel, 1972: selected epidemiologic characteristics.

An extensive rubella epidemic which occurred in Israel in the spring of 1972 provided an opportunity for several observations: 1) This epidemic had been preceded by another extensive outbreak in 1962. The interepidemic period was characterized by persistence of some rubella activity and occurrence of limited outbreaks at irregular intervals. 2) The crude annual attack rate based on the number of recorded cases among a 2,160,000 Sick Fund insured population was 315 per 10,000; this was about 5.4 times higher than the attack rate calculated from the number of cases reported to the Public Health Offices. In selected areas, where the medical personnel had been canvassed, the attack rate was 1,101 in a population of 19,131. 3) Highest specific attack rates were observed in the age groups 5-9 and 1-4, followed by the age group 10-14. 4) A slight predominance was observed in male cases aged 1-4 and female cases aged 20-24. 5) The peak occurred 1-3 months after the epidemic started, and stopped very quickly at the beginning of the summer, one month after the kindergartens and schools commenced the summer holidays.

Adolescent↗
PubMed1972

Routine administration of oral polio vaccine in a subtropical area. Factors possibly influencing sero-conversion rates.

Poliomyelitis is an important problem of public health in warm-climate countries. Studies of serological responses to vaccination in these countries have given conflicting results but in many investigations the rates have been considerably less than in countries with temperate climates. In this study three possible factors influencing sero-conversion were investigated - the season of the year when vaccine was given, the social status of the mother (as indicated by the number of years of schooling) and the presence of non-poliomyelitis viruses (NPV) in the gut when vaccine was given.Over 200 children about 2 months of age were included in the study. Each was given three doses of trivalent vaccine at 6-week intervals.The sero-conversion rates of the groups fed in winter were excellent but were slightly less good in summer. The differences were greatest in children in the lower socio-economic groups and in children excreting other enteroviruses.The conclusions are that, provided a potent vaccine is used, the factors which diminish the effectiveness of immunization in warm-climate countries can be overcome: (1) by giving three doses of trivalent vaccine; (2) by beginning vaccination at the earliest possible age (when enteroviruses are fewest); (3) by concentrating special attention on the lower socio-economic groups and if necessary by giving a reinforcing dose several months after the third dose has been given - preferably in the colder months.

Antibody Formation↗
PubMedDate not supplied

The Arjenyattah epidemic. A mass phenomenon: spread and triggering factors.

A massive epidemic of psychogenic aetiology occurred in three districts of the West Bank over two weeks in March-April, 1983. It affected 949 individuals, 727 (77%) of them adolescent females. The symptoms were not accompanied by positive physical signs or by laboratory findings. The epidemiological pattern was pathognomonic of that of a psychogenic disorder. The initial trigger was probably the odour of H2S escaping from a faulty latrine in the schoolyard of the first affected school. Subsequent spread of the disease was due to psychological and extra-medical factors, including publicity by the mass media. Spread was stopped immediately after closure of schools.

Abdomen↗
PubMedDate not supplied

Comparison of inactivated poliovirus vaccine and oral poliovirus vaccine programs in Israel.

In spite of high vaccination coverage, paralytic poliomyelitis still occurs in Israel, either in sporadic form in the urban area or in small outbreaks in the rural, non-Jewish segment. At high risk are mainly very young infants, not yet protected by poliovirus vaccine and children who have failed to seroconvert after a full course of oral poliovirus vaccine ( OPV ). In these circumstances, a new program for vaccination of young infants early in life with a quadruple vaccine containing inactivated poliovirus vaccine (IPV) and diphtheria, tetanus, and pertussis vaccines (DTP) has been tested. Administration of two doses of IPV up to the age of three and one-half months followed by a booster at the age of 10 months has produced a very satisfactory antibody response (100% seroconversion and high geometric mean titers of antibody to the three antigens), which has occurred early in life and persisted up to two years after booster. This response was similar to that observed after four doses of trivalent OPV ( TOPV ) reinforced with one dose of monovalent type 1 OPV . Two doses of the quadruple vaccine have also induced an antibody response to pertussis antigen in greater than 90% of the infants. After booster, a greater than 99% conversion rate has been recorded, which has remained unchanged at one year of follow-up. The above data have led to the modification of the poliovirus vaccination schedule in the areas at risk.

Antibodies, Viral↗
PubMedDate not supplied

Epidemiology of rubella and congenital rubella infection in Israel, a country with a selective immunization program.

A rubella immunization program directed at girls aged 12 years started in Israel in 1973, and its extension in 1980 to women of childbearing age had produced by 1983 several changes in the epidemiologic pattern of rubella infection in women of childbearing age and in the risk of congenital rubella: a 55%-77% decline in the incidence of the disease in the 15-44-year age group; a progressive reduction in the rate of seronegativity among women from greater than 20% to less than 10%; a risk of infection during pregnancy and a percentage of abortions associated with rubella infection in the 1983 outbreak that were one-twelfth and one-tenth, respectively, the values associated with the 1978 and 1979 epidemics; and an evident decrease in the frequency of cases of congenital rubella, as detected by either passive or active surveillance. It is predicted that of the women who will be pregnant in 1985, 98.2% and 94.3% of those in the 18-23 year and 24-44 year age groups, respectively, will be immune by the end of 1984.

Adolescent↗
PubMedDate not supplied

Monitoring of influenza in Israel 1976/77.

The main objectives of the monitoring were: (1) to define the prevalent virus involved in influenza activity: (2) to determine the time of its occurrence; and (3) to evaluate its extent and impact. A sudden rise in the frequency of visits associated with acute respiratory conditions in the age group 0-14 to the emergency rooms of 14 hospitals throughout the country, correlated well with the start of influenza B/Hong Kong activity; this was simultaneously attested by two different laboratories. The later and sporadic occurrence of influenza A/Victoria activity did not affect the usual trend observed in the frequency of visits to emergency rooms. An age group stratified serologic follow-up pointed to a progressively increasing rate of influenza B infection up to the age group 15-24. A crude morbidity rate of 13-18% was recorded during influenza B outbreaks in several agricultural settlements. The percentage distribution of cases was about 15,21, 26 and 37 in the age groups 0-4, 5-9, 10-14 and 15+, respectively. The mortality associated with influenza B and influenza A activity did not exceed the expected rate.

Adolescent↗
PubMedDate not supplied

Prevention of measles in Israel: implications of a long-term partial immunization program.

Following the introduction of routine measles immunization in Israel in 1967, rapid and persistent modifications in the pattern of the disease were observed, including much more limited and more widely spaced epidemics, a change in the age distribution of measles cases, and a progressively increasing herd immunity that was estimated, following the 1982 epidemic, at 91.6 percent for the first 26 generations. This pattern supports the expectation that measles can be eliminated in Israel provided a herd immunity greater than or equal to 94 percent can be achieved before the next epidemic, which is predicted for 1988-89. A logistic approach to the elimination of measles in Israel requires (a) maintenance of an immunization rate of at least 90 percent in each newborn generation; (b) identification and immunization of still susceptible children in the 1-5 year and 6-9 year age groups, to attain vaccination coverage for at least 97 percent of this population (which should result in immunity among at least 94 percent); (c) provision of similar coverage for older, susceptible individuals in selected groups of children, adolescents, and young adults at high risk; (d) disease surveillance based on an early identification of the main sources of infection and monitoring of the active foci of disease in the neighbouring territories, which are an important potential source of the introduction of infection.

Adolescent↗
PubMedDate not supplied

Basic conditions for the eradication of poliomyelitis--indications for a common prescription.

The efforts of the last decade to achieve the world eradication of poliomyelitis have resulted in several problems of methodology and field implementation of the polio control program: (1) The concept of eradication. Its present definition refers to the complete absence of activity of the wild poliovirus. It is the result of the decision to recommend the use of OPV for the world control of polio and leaves unanswered the problem of the paralytic disease associated with OPV. (2) Besides a successful vaccination policy the control of polio implies a satisfactory environment. Risk factors in the environment mean persistence of endemicity and reoccurrence of disease, even after several years of absence of polio activity. (3) Concerning the limitations of the two available vaccines, problems of immunogenicity, safety, and thermostability are associated with OPV. Use of EIPV requires a high coverage of all the ages at risk of infection, and gut immunity is lower than that induced by OPV. On the other hand, several observations point to the limitation of OPV to prevent the spread of the wild virus into the vaccinated community, as claimed for EIPV. Limitations of OPV are mainly vaccine associated paralytic disease in the developed countries, and wild virus associated disease in "vaccinated" individuals in the developing countries. Disease associated with EIPV programs is observed practically only in nonvaccinated individuals. EIPV, particularly if associated with OPV, offers a clear advantage over OPV alone, in terms of immunogenicity, safety, and protective efficacy. (4) Total elimination of paralytic poliomyelitis can hardly be conceived of without the use of the EIPV.

Forecasting↗
PubMedDate not supplied

Israel in the elimination phase of poliomyelitis--achievements and remaining problems.

Following the introduction of a combined EIPV and OPV schedule in 1990, no more cases of paralytic poliomyelitis were diagnosed and no wild poliovirus strain was isolated in the sewage. 100% seropositivity and high geometric mean titers (GMTs) to the three types of poliovirus vaccine strains and to the type 1 poliovirus 1988 epidemic strain were observed at the completion of the immunization schedule and one year later. The study of the immune profile of various age groups vaccinated with either EIPV or OPV had shown that the immunity to the epidemic poliovirus strain was less satisfactory, in terms of percent of seropositivity and GMTs, than to the poliovirus vaccine strains. In individuals previously immunized with either EIPV or OPV a high and quick immune response to both the 1988 epidemic and vaccine strains was observed after a booster dose of OPV. Follow-up to four years after the booster pointed to some decrease in the extent and intensity of the seropositivity to the 1988 epidemic strain as compared to the immune profile to the poliovirus vaccine strains. Maintaining Israel in the phase of polio elimination requires: > 95% national coverage, homogenously distributed; maintaining high immune profile to the three poliovirus types, including a satisfactory immune level to the 1988 epidemic strain in all the age groups at risk of polio; early detection of the introduction of wild poliovirus into the environment and of the occurrence of foci of indigenous activity; reducing the risk of exposure to massive infectious doses.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗