Ecologic and epidemiologic features of the circulation of streptococcus group B at a maternity clinic

In a maternity clinic the circulation of group B streptococci among the newborns, their mothers and the personnel was established during the period of 1982-1985. Group B streptococci were detected at different biotypes of newborns (the pharynx, the imbilical stump, external suditory meatus, nasal and oral mucosa, eyes and feces), their mothers (the vagina, the perianal area, breast milk, the pharynx, urine, the umbilical cord, amniotic fluid) and in the pharynx of the personnel. In this maternity clinic 15 combinations of type antigens were detected, two combinations (1a/c and 1 b/c) prevailing among them. These results confirmed earlier data concerning two possible ways of transferring infection to newborn infants: vertical, i.e. from the mother to the child during parturition, and nosocomial, i.e. from contaminated newborns or members of the personnel.     

The sensitivity to 12 antibiotics of 125 strains of Streptococcus group B isolated in a maternity home

Sensitivity of 125 strains of group B streptococci isolated from newborns, their mothers and personnel in a maternity home was studied with respect to 12 antibiotics: benzylpenicillin, ampicillin, methicillin, cephalotin, erythromycin, lincomycin, levomycetin (chloramphenicol), oxacillin, tetracycline, streptomycin, gentamicin and ristomycin. The method of serial dilutions in a solid medium was applied. All the strains were sensitive to ristomycin and erythromycin. The predominating number of the strains were sensitive to lincomycin, levomycetin and the beta-lactam antibiotics. Strains resistant or moderately resistant to benzylpenicillin, ampicillin, oxacillin, methicillin and cephalotin were detected. The majority of the strains were resistant to streptomycin, tetracycline and gentamicin. Multiple antibiotic resistance with 2-7 determinants was revealed in 11.2 per cent of the strains. The antibiotic sensitivity of the strains isolated from the newborns, their mothers and the personnel in the maternity home was on the whole similar or insignificantly differed.     

Streptococcus group B in a maternity home with a decentralized system of newborn infant care (of the mother-child type)

In a maternity hospital with the decentralized system of infant care the presence of the group B streptococcal colonization of puerperants (13.0 +/- 4.5%), newborn infants (25.0 +/- 4.4%) and medical staff (16.9 +/- 3.2%) was established. The strains isolated in this hospital belonged to 13 different serotypes and antigenic combinations with type 1 a/c dominating among them (28.7 +/- 4.8%). Group B streptococci were found to be transmitted by the vertical way in one out of two colonized mother-child pairs, in all other cases the nosocomial spread of streptococci occurred.     

Staphylococcus aureus at a maternity ward. II. Characterization of isolates by enterotoxigenicity and toxic shock syndrome toxin (TSST-1) production

Tests for enterotoxins A, B, C, D, E and TSST-1 production were carried out on 775 S. aureus strains isolated from various sources (50 mothers and neonates studied periodically, mothers and infants treated for various acute inflammatory conditions, members of hospital staff, environmental swabs) during the period 1981-1983 at a maternity ward chosen for a 3-year systematic study and on additional 97 isolates obtained in 1985 from another maternity ward. This had contributed to a better classification of strains within certain phage type groups. It was found that the distribution of S. aureus types in the particular sub-sets varied, depending on the source of isolates. At the maternity ward followed for 3 years there was a clear-cut trend towards the spread of phage-untypable isolates producing enterotoxin C whereas at ward examined for comparative purposes B enterotoxin producers of phage type 95 were predominant. The tests for enterotoxigenicity has also proved to be useful as the epidemiological marker characterizing the predominantly circulating S. aureus strain. It has been confirmed that the majority role in the spread of maternity-ward-staphylococci is played by the neonates and the factors of hospital environment.     

Prospective means of decreasing suppurative-septic diseases in puerperae and newborn infants

The comparative analysis of the occurrence of purulent septic diseases in mothers during the puerperal period and in newborns, observed in a maternity hospital before and after the introduction of the system of keeping newborns together with their mothers, showed a considerable decrease in the morbidity rate among newborn infants (6 times) and in occurrence of mastitis among puerperae (30 times). This is attributed to a decrease in the frequency of the colonization of newborns and mothers in the puerperal period by the hospital strains of staphylococci belonging to epidemic phagotypes. The gradual elimination of staphylococci of phagotype 80, which dominated for several years, from the hospital was observed. To decrease the morbidity rate, the introduction of the system of keeping newborn infants with their mothers in all maternity hospitals of the USSR is proposed.     

Circulation of methicillin-resistant staphylococci in hospitals with different profiles

Analysis of prevalence of methicillin-resistant staphylococci in hospitals with different specializations was performed. 2584 strains were isolated. Methicillin-resistant (MR) strains were present in different profile hospitals and their total prevalence between isolated strains was 12.3% while significantly varied in different hospitals (from 8% to 37%). Along with MRSA (methicillin-resistant Staphylococcus aureus), MRSE (methicillin-resistant Staphylococcus epidermidis) and MRSS (methicillin-resistant Staphylococcus saprophyticus) were presented in all studied hospitals. The prevalence of MR strains was highest among strains isolated from flame burn wounds (37%), while in samples from newborns in maternity hospital resistant strains represented 12% of isolates, and in general clinical hospital--not more than 9% of isolates. Relationship between rates of isolation of methicillin-resistant staphylococci and specialization of hospital unit was noted. For example, prevalence of MR staphylococci in isolates from newborns in ICU (47.5%) differed from the same one in maternity hospital (11.6%).     

Epidemiologic characteristics of suppurative-septic diseases in newborn infants at obstetrical hospitals keeping mother and child together and separated

The advantages of keeping mothers together with their infants at the postnatal period have been revealed; these advantages are manifested by the quick colonization of newborns by maternal microflora, thus preventing their further colonization by opportunistic hospital microbial strains. As compared with common maternity hospitals, those maternity hospitals where mothers are kept together with their infants have less intensive circulation of hospital microflora, and the morbidity rate in purulent and septic diseases among newborns is twice as low in such hospitals. All these findings may be regarded as the epidemiological substantiation of propositions in favor of further development of maternity hospitals where mothers and their infants are kept together.     

Streptococcus group B in meningitis and infection of newborn infants

Streptococci were isolated from the liquor or blood of 102 newborn infants and 16 infants in the first month of their life, suspected of having purulent meningitis, in 22 cases (18,5%). 5 isolated streptococcal strains were classified with group B on the basis of their cultural, biochemical and serological features. All of these strains were isolated from newborn infants during the first 3-4 days of their life. The occurrence of group B streptococci among all examined newborn infants was 4.8%; among the newborns with the positive results of bacteriological examination (73 infants) this figure was as high as 6.8%. The authors emphasize the necessity of producing, on an industrial scale, diagnostic preparations for the identification of group B streptococci playing a significant role in septic diseases and meningitides in newborns.     

The role of antibiotics in the prevention of cross infections in newborn infants and mothers during the puerperium]

Epidemiological efficiency of antibiotic prophylaxis of hospital infections (HIs) in maternity homes was analyzed by the materials on the clinical observation of 43995 newborns and their mothers within a period of 1986 to 1989 as well as by the data on the bacteriological examination of 6616 smears from the mucosa of the nose, pharynx, rectum and umbilical wounds of 1890 newborns carried out within the same period. It was shown that the prophylactic use of the antibiotics in the maternity homes led to changes in the microflora colonizing the newborns. The more massive was the use of the antibiotics in the departments of newborns and the postnatal departments, the more intensive was replacement of gram-positive microflora in the newborns by gram-negative organisms among which Klebsiella strains with high antibiotic resistance predominated. This involved an increase in the incidence of pneumonia and sepsis in the newborns and a higher death rate among the newborns due to HIs. In parallel there was observed an increase in the incidence of metro-endometritis in the puerperae++ and a simultaneous decrease in the number of the cases with lactational mastitis as a result of lower numbers of Staphylococcus aureus cultures isolated from various loci of the newborns. It was concluded that antibiotics were not the drugs to be used as prophylactic agents in control of HIs in maternity homes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Risk factors of development of nosocomial pyogenic and septic infections in maternity hospitals

During prospective epidemiological surveillance cases of pyogenic and septic infections (PSI) in mothers and newborns in two maternity hospitals were studied using standard case definition and leading risk factors of their development were revealed. These factors differed in two hospitals and were connected mainly with high level of patients colonization, contamination of the environment by nosocomial strains of microorganisms, and degree of participation of mother's relatives in delivery. It was shown that permission to relatives for presence on delivery did not influence on the rate of PSI. Specificity of risk factors of PSI in mothers and newborns dictates necessity to determine them in each maternity hospital.     

Nosocomial transmission of group B streptococci.

The acquisition of group B streptococci by babies in a special-care baby unit and two postnatal wards was investigated over a six-month period using serology and phage typing. Sixty-three culture-positive babies were identified in the postnatal wards, one-third of whom had been born to mothers who were not carrying the organism in the genital tract or anorectal area during labour. A non-maternal source was identified for 14 of these 21 infants: either colonised mothers and babies in the same ward or, on one occasion, a member of the hospital staff. In the special-care baby unit, however, only one instance of nosocomial acquisition of group B streptococci was recorded despite a high prevalence of colonisation in the staff on the unit and the presence of heavily colonised babies. The results of this survey suggest that although sepsis caused by group B streptococci may be the result of nosocomial transmission, this may be prevented by careful attention to hygiene.     

Colonisation of babies and their families by group B streptococci.

A high incidence of group B streptococcal disease of the newborn in West Berkshire led to a prospective study of the condition. Cultures taken from 1090 babies shortly after birth showed that 65 (6%) were colonised with the streptococcus. Thirty of these babies were assigned to group 1. Bacteriological samples were taken from babies and mothers at birth and at four, eight, and 12 weeks, and also from fathers and siblings. Fifty uncolonised babies and their families were similarly studied and served as controls (group 2). In group 1,28 of the 30 mothers and 14 of the 28 fathers examined were colonised by group B streptococci. In group 2 the streptococci were isolated from three babies, 12 mothers, and 11 out of 45 fathers during follow-up. These findings suggest that group B streptococci are carried predominantly in the lower gastrointestinal and genitourinary tracts. Most families are lightly colonised, but in others maternal colonisation is stable and heavy and the incidence of paternal colonisation high. Results of serotyping suggest that sexual transmission occurs, which may explain the difficulty in eradicating the organism during pregnancy.     

Feasibility of routine testing for hepatitis B surface antigen in hospital employees and restriction of carriers.

In 1972-73, 48 hospital staff members were tested selectively for hepatitis B surface antigen (HBsAg); 4 (8.3%) were found to be HBsAg-positive. In 1974-75, 1415 staff members were tested routinely before employment and at periodic health examination; 25 (1.8%) were found to be HBsAg-positive. Of the HBsAg-positive staff members 55.2% were Asians, this proportion being significantly (P less than 0.05) greater than that of any other ethnic group, and 31.0% were southern Europeans. Nurses and laboratory technologists were the largest professional groups among the HBsAg-positive staff, each accounting for 20.7%. Our results indicate that it is impractical to carry out routine testing of hospital staff for HBsAg. Selective testing and restriction from work in their units is proposed for staff of the renal and peritoneal dialysis units, the emergency department and the intravenous team and dietary staff who handle food directly.     

Measures to prevent outbreaks of hospital infections

On the basis of the analysis of 69 outbreaks of hospital infections registered in the USSR in 1986-1989, as well as additional observations made by the authors, a number of factors which determined the present state of the problems concerning this kind of morbidity in the USSR were established: an insufficient level (in cases of enteric infections) or a low level (in cases of purulent septic infections) of etiological diagnosis; poor efficiency of the epidemiological investigation of outbreaks; defects in the work on the prophylactic detection of potential sources of infection among medical staff, parturient women or mothers taking care of their infants. Some possible solutions on these aspects were proposed. Cases of outbreaks of hospital infections among newborns were used as an example demonstrating that such outbreaks were caused mainly by breaches of antiepidemic and sanitary rules in respective hospitals; thus, in one-third of the cases of outbreaks such breaches were observed in maternity clinics with insufficient material and technical equipment. The prevention of these breaches is considered to be the main road to the solution of the whole problem of the prevention of epidemic outbreaks in hospitals.     

医院工作人员鼻腔葡萄球菌带菌状况年度推移的调查报告

本文报道1989年从202名医院工作人员鼻腔分离葡萄球菌的带菌状况和药敏性检测结果。并将此结果同作者等于1985年对200名同类人员检测的结果相比较,作了年度推移的调查分析发现1989年度的总带菌率(76.6％)比1985年度(84.5％)略有下降,但其中的金黄色葡萄球菌带菌率却从1985年的7.5％上升为10.4％。从1989年和1985两个年度的调查中,均发现临床科室人员金葡菌带菌率高于其它辅助科室人员,说明医务人员带菌率与接触病人成正相关关系。分离菌株对12种抗菌药物的耐药性检测结果显示,1989年分离菌株对其中9种的敏感性下降,并且从耐药谱显示出对5种抗菌药物耐药的多重耐药菌株明显增多。另从金葡菌的耐药情况,也看出1989年的耐药率高于1985年菌株。还在1989年分离的金葡菌中出现25％的耐甲氧西林菌株。     

Collagen of umbilical cord vein and its alterations in pre-eclampsia

The state of the vascular system of the mother and of placenta is known to exert a great influence on intrauterinal development of the fetus. Pre-eclampsia is the most common pathological syndrome connected with pregnancy. Since collagen is one of the main constituents of the vessel wall a comparison was made with collagen content and its molecular polymorphism in umbilical cord veins of newborns from healthy and pre-eclamptic mothers. It was found that umbilical cord veins of newborns from mothers with pre-eclampsia contained 18% less collagen than those of the newborns from normal pregnancies. This decrease was accompanied by a slight decrease of collagen solubility, but all its types (I, II, IV, V and VI) were present. However, the umbilical vein wall of newborns from mothers with pre-eclampsia contained relatively less of type I and more of type III collagen than the normal umbilical cord. These differences may be connected with a disturbance of blood flow in fetus of a woman with pre-eclampsia.     

Delineation of suppressor and helper activity within the OKT4-defined T lymphocyte subset in human newborns

Lymphocytes taken from the cord blood of newborns have active suppressor activity. Using in vitro PWM-stimulated cocultures, unfractionated T cells from newborns potently suppressed the expected immunoglobulin G (IgG) synthesis of their mothers' peripheral blood lymphocytes (PBL). Using positive and negative selection techniques, we characterized the active suppressor cell as expressing the OKT4+T8- phenotype. This cord blood lymphocyte subset suppressed maternal IgG synthesis after depletion of maternal suppressor cells, implicating the ability of newborn T cells to suppress directly rather than by inducing adult suppressor activity. Sublethal amounts (1500 rad) of gamma-irradiation fully abrogated the suppressor activity of cord blood T lymphocytes. Radioresistant cord T cells provided T cell help. Irradiation of cord OKT4+ and OKT8+ populations and their subsequent culture with maternal B cells determined that helper activity was a radioresistant subpopulation of the OKT4+ subset. These results indicate significant differences in the functional properties of T cell subsets from adults and newborns. Population studies determined that cord blood lymphocytes had a greater proportion of OKT4+ cells and lower proportion of OKT8+ cells than PBL from unrelated adults. The mothers tested had similar proportions of OKT4+ cells as their babies, and these levels are significantly higher than those of unrelated adults.     

Epidemiological investigation of nosocomial outbreak of staphylococcal skin diseases in neonatal ward

During a 1-month period, eight neonates developed staphylococcal skin disease diagnosed as a bullous impetigo in the maternity unit of the Provincial Hospital in Gdansk. An epidemiological investigation based on phenotyping and genotyping methods was performed. All neonates involved in the outbreak, their mothers and 15 staff members were screened for carriage of Staphylococcus aureus by nasal swabs. Isolated strains were compared with strains cultured from affected skin and purulent conjunctiva of infected newborns. Isolates were analyzed for the presence of the etA and etB genes using polymerase chain reaction and genotyped by pulsed-field gel electrophoresis (PFGE) and coa gene polymorphism. The analyzed S. aureus strains were methicillin-sensitive and could be divided into two groups according to antibiotyping, phage typing, coa polymorphism and PFGE pattern. The first group consisted of etA and etB negative strains, and the second one involved only the etB positive ones. Our results have shown that there were two different clusters of infection caused by two populations of S. aureus strains. Among the 15 medical staff members screened we have found seven carriers. However, phage typing revealed that distinct strains unrelated to the outbreak isolates were carried. Although we have not been able to establish the source of bacteria involved in the outbreak, our results suggest that for both groups, mothers could be the source of the infecting strains. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

The spread of Klebsiella in obstetrical hospitals and the biological properties of the isolated strains]

Examination of 278 newborn infants, parturients, and medical personnel in two maternity hospitals revealed a high level of Klebsiella colonization of all examined biotopes of infants (the nasal cavity in up to 36.5% of cases) and the skin of the mammary glands of nursing mothers (in 36.2% of cases). In the intestine and the nasal cavity of parturient women and medical personnel Klebsiella could be detected 3-10 times more often than in the same biotopes of nonhospitalized pregnant women. From 254 objects of the hospital environment Klebsiella were isolated in 9.05% of cases. The possibility of the transmission of Klebsiella in hospitals by patients with inflammatory processes in their genitals were established. The diversity of the serological picture of strains of most K-serovars and a short period of their isolation were shown. In one hospital serovar K10 with some features of a "hospital" strain was isolated. The strains under study were sensitive to aminoglycosides, cephamesine, chlorhexidine, but resistant to semisynthetic penicillins and chloramine.     

Pseudomonas aeruginosa: study of antibiotic resistance and molecular typing in hospital infection cases in a neonatal intensive care unit from Rio de Janeiro City,Brazil

This study had the objective of to analyze the demographic and bacteriologic data of 32 hospitalized newborns in an neonatal intensive care unit of a public maternity hospital in Rio de Janeiro city, Brazil, seized by Pseudomonas aeruginosa sepsis during a period ranged from July 1997 to July 1999, and to determine the antimicrobial resistance percentage, serotypes and pulsed field gel electrophoresis (PFGE) patterns of 32 strains isolated during this period. The study group presented mean age of 12.5 days, with higher prevalence of hospital infection in males (59.4%) and vaginal delivery (81.2%), than females (40.6%) and cesarean delivery (18.8%), respectively. In this group, 20 (62.5%) patients received antimicrobials before positive blood cultures presentation. A total of 87.5% of the patients were premature, 62.5% presented very low birth weight and 40.6% had asphyxia. We detected high antimicrobial resistance percentage to b-lactams, chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline among the isolated strains. All isolated strains were classified as multi-drug resistant. Most strains presented serotype O11 while PFGE analysis revealed seven distinct clones with isolation predominance of a single clone (75%) isolated from July 1997 to June 1998.