Poliomyelitis control in Israel, the West Bank and Gaza Strip: changing strategies with the goal of eradication in an endemic area.

Israel has faced the challenge presented by epidemic poliomyelitis by using different immunization strategies. In the 1950s, inactivated poliovirus vaccine (IPV) helped to reduce the total burden of the disease, but cases continued to occur. Introduction of oral poliovirus vaccine (OPV) in mid-1961 had a dramatic effect in controlling an extensive epidemic of poliomyelitis; however, poliovirus activity and cases continued during the 1970s, and at a low level in the 1980s. A localized outbreak of 15 cases of poliomyelitis in 1988 occurred in an area using enhanced potency IPV (eIPV) only. This led to a revision of poliomyelitis immunization policy. The successful poliomyelitis control in the West Bank and the Gaza Strip using both OPV and IPV since 1978 shows the advantages of a combined approach. This programme was therefore adopted in modified form in the whole of Israel, the West Bank and Gaza. Since late 1988, no cases of poliomyelitis have occurred in any of these three areas, indicating the success of the combined poliomyelitis immunization programme. These experiences may be helpful to other countries, especially those where there is a danger of importation of wild poliovirus, and to prevent vaccine-associated disease. The combined approach provides an additional immunization model in the international effort to eradicate poliomyelitis.

Combined live and inactivated poliovirus vaccine to control poliomyelitis in a developing country--five years after.

The Gaza Strip is an area in transition which in the 1960's had a high prevalence of malnutrition and infectious diseases. The infant mortality was approximatively 140 per 1000 live births. Pediatric Services were almost non-existant. Trivalent oral poliovaccine (TOPV) has been used since 1967. Coverage however did not exceed 70%. From 1973 a network of comprehensive Child Health Centers was spread throughout the area, a set of laws was passed which made vaccination obligatory and the community became heavily involved in health education. These measures resulted in a vaccination coverage, from fixed centers, of over 90% of the susceptible infant population. Though infant mortality decreased rapidly, poliomyelitis was less affected and the mean annual incidence of the paralytic disease until 1977 continued to be 10 per 100,000 inhabitants. Two outbreaks caused by poliovirus Type 1 were registered in 1974 and 1976 with an incidence of 18 per 100,000 inhabitants. In these outbreaks 34% and 50% of the affected children, respectively, had received 3-4 doses of (TOPV). A new vaccination schedule was implemented in 1978 combining TOPV and inactivated polio vaccine in the form of an injectable quadruple vaccine. In the first three years following this change the annual incidence of the paralytic disease dropped from 10 to 2.2 per 100,000 inhabitants. In the following 5 years (1981-1985) only 4 cases of paralytic poliomyelitis were discovered, an annual incidence of 0.16 per 100,000 inhabitants. A serosurvey was done in 1980 on 117 immunized children age 6 months to three years.(ABSTRACT TRUNCATED AT 250 WORDS)

Citrobacter koseri isolated in Israel, 1972-83.

Cultures of Citrobacter koseri (syn. C. diversus), an opportunistic pathogen that was isolated in Israel during 1972-83, were studied by sero- and biotyping and for susceptibility to antibacterial agents. Of 1,172 cultures, 96% were isolated from adults, more than half from urinary tract infections. Other frequent sources were superficial wounds and discharges from the respiratory and genital tracts. Seventeen strains originated from blood cultures of patients with sepsis and four from the cerebrospinal fluid of newborns with meningitis. The isolates belonged to 17 O groups, 60 serotypes and 5 biotypes. The most frequent serotypes were 15:a:[2], first identified in Israel, and 1:a:[2]. The most frequent biotypes were c and a. No correlation was found between sero- or biotypes and source of isolation or type of disease. Of 720 cultures tested for sensitivity, all were resistant to ampicillin and carbenicillin, but only 9.3% were resistant to one or more of nine other antibacterial agents tested.

Successful results of a program combining live and inactivated poliovirus vaccines to control poliomyelitis in Gaza.

Trivalent oral poliovirus vaccine ( TOPV ) has been used in Gaza since 1967. After an initial decrease of 33% in the incidence of the paralytic disease, no further decrease could be noted. The mean annual incidence until 1977 was 10 per 100,000 inhabitants. Two outbreaks caused by poliovirus type 1 were registered in 1974 and 1976 with an incidence of 18 per 100,000 inhabitants. In these outbreaks, 34% and 50% of the affected children, respectively, had received three to four doses of TOPV . A new vaccination schedule was introduced in 1978, combining live and inactivated poliovirus vaccines. In the years 1978-1980, the incidence decreased to 2.6 per 100,000 inhabitants; and during 1981-1982, only three cases were recorded. These results indicate that a schedule like the one used in Gaza could serve as a model to control poliomyelitis in developing countries where TOPV alone is not successful.

Results of a program successfully combining live and killed polio vaccines.

Oral polio vaccine (OPV) has been used in the Gaza Strip since 1968. Although vaccine coverage had reached 80 to 90% of the infant population, the epidemiological pattern of the paralytic disease had not changed significantly as of the beginning of this study. The mean annual incidence continued to be around 10/100,000. Two outbreaks occurred, in 1974 and 1976, involving 75 and 77 children, respectively, an incidence of 18/100,000. In these two outbreaks, 34 and 50% of the affected children, respectively, received 3 to 4 doses of OPV. A serological survey done after a vaccination campaign with monovalent Type 1 vaccine showed an unexpectedly low percentage of seropositives. A parallel was found between the prevalence of diarrheal disease and vaccine failure, and a causal effect was postulated. To overcome this problem, a program of immunization was started early in 1978 combining both live and killed polio vaccines. Although cases of polio continue to appear, the incidence has been reduced to 2.4/100,000 population. In 1981, only one case was reported, in an unvaccinated child. Thus, it would seem that the new vaccination schedule combining live and killed vaccines makes eradication of polio a possibility.

Susceptibility to rubella and borderline immunity.

Immunity to rubella in women of childbearing age has been determined by hemagglutination inhibition (HI) and/or hemolysis in gel (HIG) methods. Susceptibility was defined as absence of antibody at a dilution of 1:16 in HI and a hemolysis zone of less than 7 mm in HIG tests. In screening 30,330 women during the years 1980-81, 13.7% were found seronegative. Among 439 women immunized with RA-27/3 vaccine, 92% showed seroconversion, when tested by HI greater than or equal to 2 months following vaccination. Paired sera from 35 vaccines who remained seronegative were tested by two additional methods: sensitizing antibody (SA) and enzyme-linked immunosorbent assay (ELISA). Ten women were confirmed as vaccine failures by these two methods. The remaining women presented the following results: 19 had borderline and stable titers in their paired sera and 6 showed seroconversion, by SA and ELISA. These results indicate that both SA and ELISA are more sensitive than the HI and HIG tests for evaluation of rubella immunity and response to vaccination.

Extended scheme for serotyping Campylobacter jejuni: results obtained in Israel from 1980 to 1981.

The serotyping scheme for Campylobacter jejuni previously developed in the National Center for Campylobacter, Jerusalem, was extended by the use of 20 new sera and modified by the absorption of the sera, when necessary, with homologous boiled cultures or heterologous live cultures. The extended scheme is based on slide agglutination of live suspensions and is performed in two stages: pretesting with four pooled sera and final testing with monovalent sera. So far, 34 serotypes have been recognized. Among 442 isolates of C. jejuni, 86.4% could be typed with this scheme. Of the 382 cultures typed, 90% reacted with one single serum, and the remainder showed a complex antigenic structure. The frequent serotypes identified were: 11 (12.9%), 12 (8.2%), 18 (6.3%), and 3 (6.1%). When epidemiological data were available, the results of the serotyping corresponded with the epidemiological evidence.

Survey of pneumococcal types in Israel, 1978-81.

The most common capsular types of Streptococcus pneumoniae that prevailed among 436 cultures isolated in Israel (1978 through 1981) were: 1, 14, 6B, 23F, 19A and 5. Among the 301 isolates from significant sources, 66.1% belonged to 14 capsular types that are included in available pneumococcal vaccines. Among those that were not included in these vaccines, the most frequent types were: 5, 19A and 6B. The addition of these three capsular polysaccharide types to the vaccine used in Israel would result in a vaccine coverage of approximately 85%.

Edwardsiella tarda isolated in Israel between 1961 and 1980.

Edwardsiella tarda was isolated from patients, water tortoises (Clemmys caspica), and samples of water from Lake Kinnereth, the river Jordan, well water, and sewage water. Of the 53 isolates, 35 belonged to completely identified serotypes, among them 7 new ones. Fourteen cultures had O antigens, and one had an H antigen, different from those previously described. Three serotypes isolated from patients were also found in other sources: water tortoises, lake water, or both.

Leptospirosis in man, Israel, 1970-1979.

In 1970-1979, the incidence of human leptospirosis in Israel was 0.7 per 100,000 population. The majority of the cases (62%) occurred in northeastern Israel (Upper Galilee). Prior to 1973 the main infecting serotypes were grippotyphosa (41%) and Hebdomadis szwajizak (31%). Following the first outbreak of Hebdomadis hardjo infection in 1973, a change occurred in the epidemiologic pattern of human leptospirosis, with hardjo becoming the most common serotype (59%). Hardjo infection outbreaks were sporadic and localized to dairy farms. The peak of incidence was during the summer months, June-September. All the patients with hardjo were dairy workers. The illness was relatively mild and mostly unicteric. Cattle seemed to be the principal source of hardjo infection for man.

Antigenic scheme of Citrobacter koseri.

An antigenic scheme, based on the determination of 17 somatic and 9 flagellar antigens, is proposed for Citrobacter koseri. Seven of the flagellar antigens constituted the specific phase (a through g), and the others (1 and 2) were nonspecific. Of the 238 theoretically possible serotypes, 48 were identified among 680 cultures examined.

Improved method for cholera diagnosis.

The use of the oxidase test is proposed to discover sparse colonies of cholera vibrios on a plate of Pril nutrient agar seeded directly with the suspected stool sample or after enrichment. This method also enables the detection of other oxidase-positive potential pathogens, such as non-agglutinating vibrios, Aeromonas hydrophila, Pseudomonas spp., and other nonfermentative organisms.

Antibiotic-resistant mutants of Mycoplasma pneumoniae.

Sensitivity tests of Mycoplasma pneumoniae to antibiotics were performed with 28 strains to determined the minimum inhibitory concentration (MIC) of the antibiotics, the MIC after 14 days' incubation at 37 C, and the minimum plasmacidal concentration. The antibiotics tested were erythromycin, tetracycline, oxytetracycline, chloramphenicol and streptomycin. The MIC of erythromycin was around 0.01 microgram/ml, whereas that of tetracycline was approximately 0.1 microgram/ml. Of the 28 strains tested, nine isolates gave rise to mutants resistant to high concentrations of erythromycin, chloramphenicol and streptomycin; none of the strains produced mutants resistant to tetracycline. Of the nine resistant mutants, three strains were isolated from erythromycin-treated patients. One strain, isolated from a patient treated with erythromycin for 18 days, was resistant to the antibiotic in a concentration greater than 100 microgram/ml.

New Salmonella serovar, Salmonella eingedi [61,62,7:f,g,t:1,(2),7].

A new Salmonella serovar, Salmonella eingedi, was isolated from the intestinal content of a snake, Coluber rhodorhachis, and later also from the diarrheal stools of two children.