Immunoserodiagnosis of acute Streptococcus pneumoniae and Chlamydia pneumoniae infections in the period of epidemic rise of non-hospital pneumonia in children in St. Petersburg, 1998-2001

The dynamics of the antibody formation to S. pneumoniae and C. pneumoniae in children during the epidemic outbreak of non-hospital pneumonia in St. Petersburg in 1998-2001 was studied. For the first time the inhibiting influence of acute C. pneumoniae infection on the synthesis of antibodies to S. pneumoniae in acute mixed infection was established. The prolonged (up to days 29-39 of the disease) circulation of IgM and IgG antibodies in acute chlamydial infection, as well as the prevalence of the primary infectious process, were detected.     

Pneumococcal and chlamydial infections in a closed community

An epidemic outbreak of acute respiratory infection (295 patients) in an organized group of young people was observed in December-May 1997-1998. Pneumococcal etiology was established by means of indirect immunofluorescence reaction in cases of outpatient pneumonia (81.9%), acute bronchitis (80%) and acute respiratory diseases (92.5%). Respiratory chlamydiosis caused by Chlamydia pneumoniae was detected in enzyme immunoassay with the use of immunoComb Chlamydia Bivalent IgG in patients with pneumonia (66.7%), acute bronchitis (60%) and acute respiratory diseases (50%). Synergic relationship between pneumococcal and chlamydial infections was noted.     

Current features of HIV-infection in St. Petersburg

Dynamics of HIV-infection epidemic in St. Petersburg was analyzed. New features of epidemic process, which were not observed in St. Petersburg earlier, whereas noted in other territories of Russia, were revealed and described.     

Etiology of acute bronchitis in young children

In the microbiological examination of 132 children aged 0-3 years with acute bronchitis, Streptococcus pneumoniae and Haemophilus influenzae at a concentration of greater than or equal to 10(4) cells/ml, as well as different species of opportunistic bacteria, were isolated from tracheobronchial washings obtained from 100 of these children. S. pneumoniae and H. influenzae were found to play the leading role in the etiology of the acute bacterial inflammatory process in acute bronchitis in children.     

Etiology of influenza according to the data of serological diagnostics in hospital patients in St. Petersburg at the period of 1968 - 2000

The specific features of the etiology of influenza in children and adults at the period of the simultaneous circulation of two subtypes of influenza virus A, according to the results in the hemagglutination-inhibition reaction in 261,490 influenza and ARD patients hospitalized in St. Petersburg in the course of 32 years, were analyzed. The results of serological diagnostics was shown to correspond to the data of the identification of influenza viruses in Russia and all over the world. At the period of epidemics diseases caused by the main infective agents of the epidemics were detected in 11.0% - 51.0% of cases and by concomitant infective agents, in 0.6% - 12.4% of cases. After the reappearance of influenza virus A(H1N1) in circulation higher frequency of mixed forms of infection and the presence of competition between the subtypes of influenza virus A was noted. In young children a decrease in differences in the proportion of influenza cases, caused by the main and concomitant infective agents, as well as between the detection of influenza in epidemic and in summer periods, was registered.     

Data on the study of the epidemiology of rotavirus infection in Leningrad

The results obtained in the study of rotavirus infection in Leningrad in 1984-1987 are presented. Enzyme immunoassay techniques were used for the examination of 4,715 children aged 0-14 years and 1,162 adults with diagnosed acute enteral infection of unknown etiology, as well as the control group of 556 of healthy children aged 0-6 years and 77 healthy adults. The rotavirus antigen was detected in 1.210 sick children (25.7%) and 133 sick adults (11.4%), as well as in 6 healthy children (1.1%), but not detected in healthy adults. The following epidemiological regularities of rotavirus infection were established: the highest sick rate among children aged 0-2 years and a low level of rotavirus carriership among healthy persons; the seasonal character of rotavirus infection, its outbreaks occurring in winter and the epidemic periods varying in their character and duration in different years; the prevailing role of rotaviruses in the development of winter rises of acute enteral infection of unknown etiology in the city among children aged 0-2 years. The problem of the respiratory syndrome in rotavirus diarrhea is discussed. The rotavirus antigen was detected in 39 out of 144 children (27%) with diagnosed acute respiratory virus diseases and in 4 out of 99 nasopharyngeal washings (4%) from diarrhea patients. Adenoviruses were shown to play an insignificant role in the etiology of diarrhea (10% of cases).     

Immunological research and criteria for determining the etiology of acute bronchitis in young children

In the determination of the etiology of acute bronchitis in children, a complex of microbiological and immunological methods should be used. The isolation of Streptococcus pneumoniae and Haemophilus influenzae at a concentration of greater than or equal to 10(4) cels/ml from tracheobronchial washings is the early and most significant method for the determination of the etiology and therapy of acute bronchitis. On the basis of microbiological and immunobiological criteria, the etiological role of S. pneumoniae has been determined in 78% of patients and that of H. influenzae, in 48% of patients, mainly in association with pneumococci.     

Mycoplasma pneumoniae infections in a rural setting in Canada.

Mycoplasma pneumoniae infection was monitored in patients with symptoms of acute respiratory tract infection in a village in southeastern Ontario from April 1983 to April 1984. M. pneumoniae was isolated from 51 (48%) of the 106 patients. The incidence began to increase in May 1983, reached a peak in July and declined to normal by mid-August. During the epidemic period M. pneumoniae was detected in 36 of the 43 symptomatic patients. The most prominent features of the outbreak were the considerable intrafamilial attack rate and the high frequency of pneumonia among infected patients. Treatment with tetracyclines and erythromycin reduced the duration of the illness and accelerated the resolution of symptoms.     

HIV infection in Saint Petersburg: the changing face of the epidemic

The specific features of the epidemiological situation in St. Petersburg at the first stage (1987-1995) and the second stage (1986-1999) of the development of HIV infection are described. During this period morbidity in HIV infection, starting from the insignificant rate of growth, sharply increased. For the first time injecting drug users were noted to come out to the foreground in the structure of the contingent of persons affected by HIV infection (57.5% and 72.6% in 1998 and 1999 respectively). Such change on the epidemic situation requires corrections in the strategy and tactics of preventive measures and medical assistance. To control HIV infection among drug users, only the combination of medical assistance given by narcologists with the realization of all elements of the program "Harm Reduction" can be effective.     

The etiological structure of acute bacterial meningitis in different regions]

In 1985-1989 the etiological structure of acute bacterial meningitides (ABM) in children was studied in 4 largest industrial cities in different regions of the European part of the former USSR, as well as in 2 industrial cities of western Siberia. Due to the common methodological approach used in all investigations, comparable data were obtained in all cities. These investigations revealed that meningococci caused 53.0-86.7% of all cases of ABM in children, which corresponded to moderately increased morbidity rate in meningococcal infection (3.9-11.0 cases per 100,000 of the population, mostly 5.0-7.0 cases) in these cities with its progressive decrease during 3-4 years of observation. The gradual change of meningococci from group A, prevailing in the '70s and early '80s, to group B and in some cases the appearance of group C meningococci, accompanied by a decrease in morbidity rate, were noted. In St. Petersburg the indices of ABM morbidity in children aged up to 5 years for 1987 and 1988, caused by Haemophilus influenzae (0.74 and 4.13) and pneumococci (3.23 and 4.86), could be calculated. A great number of ABM cases of unclear etiology (15.9-33.3%) suggests that the number of ABM cases caused by these two infective agents was underestimated.     

实验室内树鼩爆发间质性肺炎的报告

在动物室内饲养的树鼩于2003年4月至8月爆发了一次间质性肺炎。疫情特征为患病动物呼吸窘迫,发病急,死亡率高,主要累及新生或幼年动物,红霉素类抗生素有显著的防治效果。病理检查见光镜下肺组织呈间质性肺炎改变,肺泡腔内无渗出。推测此次疫情的病原为肺炎支原体。     

Clinico-roentgenologic manifestations of intestinal lesions in pseudotuberculosis

The authors presented the results of clinical and x-ray investigation of 102 patients with epidemic pseudotuberculosis (EP). The diagnosis was established on the basis of epidemiological evidence and the results of clinical and serological investigation. The affection of the digestive organs was observed not only in the abdominal type of EP but also in its other types. X-ray examination of the digestive organs revealed terminal ileitis in 56.8% of the patients alongside with functional disorders. X-ray examination plays a certain role in the differential diagnosis of EP from other diseases of the ileocecal region, in particular from acute appendicitis.     

The verification of the results of screening antibodies to hepatitis C virus in blood donors

6,744 persons were examined for the presence of antibodies to hepatitis C virus (HCV) before blood donation (4,219 persons in Moscow and 2,525 persons in St. Petersburg). The serum samples found to contain antibodies to HCV were additionally studied by the immunoblot techniques. The positive results of antibody screening were registered in 78 persons: 26 persons in Moscow (0.62%) and 52 in St. Petersburg (2.05%). In both cities the positive results of screening were confirmed in 62% of cases. Different occurrence of the profile with the presence of antibodies to all fragments of the virus: 52% in Moscow, 12% in St. Petersburg (chi2 = 12.11; p < 0.001). Considerable differences were also registered in the spread of individual antibodies.     

Significance of Legionella pneumophila in human respiratory pathology

The etiological structure of acute pneumonia and acute respiratory diseases was studied with a view to establishing the proportion of L. pneumophila among other causative agents of such diseases. A total of 299 patients were examined over time. The etiological diagnosis based on the data of serological examination was made in 70.6% of the patients with acute pneumonia and in 65% of the patients with acute respiratory viral infections and influenza. In the etiology of pneumonia, the leading role was found to belong to influenza A (H3N2) and B viruses, as well as to adenovirus, while in the etiology of acute respiratory viral infections and influenza, to influenza B virus, adenovirus and Mycoplasma pneumoniae. The importance of L. pneumophila in the etiology of acute pneumonia and acute respiratory diseases was shown. The proportion of L. pneumophila proved to be, on the average, 9.9% in acute pneumonia and 9.8% in acute respiratory diseases. L. pneumophila occurred most frequently in mixed infections in combination with adenovirus and influenza B virus. Diseases of Legionella etiology were found to have a seasonal character, occurring mostly in winter and spring.     

Etiology of pneumonia in children in the absence of pneumococcal and antihaemophilus vaccines

Childhood pneumonia represents an important pathology, a cause of morbidity and mortality worldwide. Our study aims to determine etiology of pneumonia in hospitalized children using several laboratory methods. We performed a prospective study that enrolled 560 children age 1 up to 18 years old all diagnosed with pneumonia by clinical and radiological features. We applied various laboratory methods (serologic, bacteriologic: bronchial aspirate, sputum, pleural effusion and blood culture) in order to identify a pathogen agent that caused pneumonia. Statistics used Statistical Package for Social Science. An etiology was established in 68.92% of all cases included in the study, as follows: in 33.93% viral etiology, in 25.13% we identified Streptococcus pneumoniae, in 20.2% Mycoplasma pneumoniae, Klebsiella pneumoniae in 8.29%, Staphylococcus aureus in 7.51%, Haemophilus influenzae in 4.92%. Mixed bacterial and viral infection was identified in 4.40% of all cases. A potential causative agent of childhood pneumonia was determined in most cases, S. pneumoniae being the main agent involved in community acquired childhood pneumonia in our country.     

Parameters of cerebral blood flow of 7- to 11-year-old children living in northern European Russia

Doppler sonography and rheoencephalography were used to study cerebral hemodynamics of young schoolchildren in the village of Klimovskoe (Konosha raion, Arkhangel’sk oblast, Russia). Mean linear blood flow velocities (LBVs) in the major cerebral vessels did not differ significantly from the velocities measured in age-matched children living in St. Petersburg. The index of resistivity was lower in the residents of the North than in their counterparts in St. Petersburg, which suggests a decreased tone of resistive vessels of the children living in the North. Asymmetry of the LBVs through the homonymous cerebral arteries of the left and right hemispheres was found in 67% of children examined. Asymmetry of the LBVs in the anterior, middle, and posterior cerebral and vertebral arteries (VAs) was correlated with a malformed posture (such as scoliosis or a slouch). In most children examined, sideward head rotation was accompanied by compression of VAs at the level of the C ₁ and C ₂ cervical vertebrae; in 71% of them, this condition could be regarded as a hemodynamically significant stenosis. In all children, a decreased LBV observed in one of the VAs was completely compensated by an increased LBV in its contralateral counterpart. Doppler sonographic signs of dystonic VAs and/or asymmetrical LBVs in the VAs were found in 79% of children examined. These children can be supposed to have latent disorders of blood flow in the VA basins caused by vertebral influences (related to irritation of the periarterial nervous plexus or cervical autonomic plexuses). The schoolchildren living in the North exhibited a lower reactivity of their cerebral vessels to hypo-and hypercapnia than their counterparts living in the central parts of the Russian Federation or in St. Petersburg. Regional differences were found in the sensitivity of cerebral vessels to hypocapnia. The volume of blood in the basins of the internal carotid arteries determined in a hypocapnic test was decreased; it was increased in the basins of VAs. This fact can be interpreted as a regional redistribution of the cerebral circulation caused by extreme environmental factors stimulating vital regulatory sites of the brainstem.     

Ecological aspects of phebotomine (Diptera,Psychodidae) in an endemic area of tegumentary leishmaniasis in the northeastern Argentina, 1993-1998

The first epidemic tegumentary leishmaniasi? outbreak in the province of Misiones was recorded in 1998, in the locality of Puerto Esperanza. Phlebotominae collected in the region, previously or simultaneously to the outbreak (September 1993-December 1998) showed that the species Lutzomyia intermedia s. l. was prevalent (94%, n 6,150) at all the sites sampled with miniature light trap (10) and Shannon trap (3). L. pessoai, L. whitmani, L. migonei, L. shannoni, L. fischeri, L. misionensis, Brumptomyia avellari and B. guimaraesi were also captured. Sand fly distribution in time and space suggests that in the province of Misiones (1) the species already present before 1990 could give rise to the epidemic by the density/dispersion fluctuation of their local populations; (2) the abundance of L. intermedia s. l. was associated with environments with ecotones of primary-secondary vegetation, close to water bodies and with moderate human disturbance; (3) this species showed, towards the end of 1997, peaks of exceptional abundance, subsequent to rainfall peaks in 1996. This increase in abundance of potential vector sand fly populations close to houses with colonizable surroundings could have generated the 1998 epidemic outbreak.     

Etiological structure of pneumonias in children and adults

The bacteriological study of sputa, nasopharyngeal smears and bronchial washings taken from pneumonia patients has shown that the leading etiological agent was Streptococcus pneumoniae isolated in the diagnostic titre (10(7) bacteria per ml) in 78.1% of the cases. Staphylococcus aureus, Haemophilus influenzae, enterobacteria and yeast-like fungi have been found to play an insignificant role in the etiology of acute pneumonia (2.5 +/- +/- 0.9%). The results of the serological diagnosis by means of the complement fixation test have revealed that, alongside S. pneumoniae, the following infective agents are of etiological importance in cases of acute pneumonia: respiratory viruses (more than 50%), Mycoplasma pneumonia (10%), Chlamydia psittaci (6.4%) and Legionella pneumophila (3.8%). The study has first revealed that, under the conditions of Alma-Ata, serotypes 19, 23, 8 and 4 prevail among circulating pneumococci. This study has also shown that the use of M. pneumoniae antibody erythrocyte diagnosticum enhances the detection rate of mycoplasma infections in pneumonia patients.     

Cryptic species in Diacyclops bicuspidatus (Copepoda:Cyclopoida): evidence from crossbreeding studies

The problem of cryptic species in Diacyclops bicuspidatus was examined using interpopulation crosses of four populations collected from a: (1) permanent flood lake in Kiev, Ukraine, (2) temporary pool in Kiev, (3) permanent pond in St. Petersburg, Russia (1200 km to north from Kiev) and (4) lake in Crimea (1100 km south of Kiev). The only interpopulation crosses to exhibit fertility were those between the St. Petersburg population and each of the two Kiev populations. The crosses between the Kiev and Crimea populations, between the St. Petersburg and Crimea populations, and between the two Kiev populations were sterile, as evidenced by either nonviable eggs, empty egg membranes or incomplete copulations. The F₁ hybrids resulting from the St. Petersburg permanent pond X Kiev flood lake cross were fertile and produced mature F₂ offspring. Some data on development times of parental and hybrid lines are presented. The St. Petersburg parental line showed development times almost twice as long as those of the Kiev flood lake population when reared at 10 °C and 20 °C in the laboratory. The F₁ offspring of the cross between St. Petersburg females and Kiev floodlake males showed similar development times to females of the St. Petersburg parental lines at both temperatures. The F₂ hybrids also showed development times that approximated those of the St. Petersburg parental line. These crossbreeding studies suggest the presence of cryptic species in the D. bicuspidatus inhabiting ecologically different populations in many parts of its large holarctic range.     

Familial hypercholesterolemia in St. Petersburg: diversity of mutations argues against a strong founder effect

Examination of low-density lipoprotein (LDL) receptor, its promoter, and major exon-intron boundaries from a sample of patients with familial hypercholesterolemia (FH) from 74 probands of St. Petersburg revealed 34 mutations and 8 widely spread polymorphisms at this locus. Only four mutations were considered silent, while the other 30 are likely associated with familial hypercholesterolemia (FH). Mutations in the LDL receptor gene, inducing the disease, were identified in 41 (55%) out of 74 families with FH. Mutation R3500Q in apolipoprotein B (APOB) gene was not detected in all probands. Therefore in the families lacking mutations hypercholesterolemia was induced by mutations in the introns of the LDL receptor gene or by other genetic factors. Nineteen mutations causing disease progression were described in St. Petersburg for the first time, while 18 of them are specific for Russia. Among Ashkenazi Jews, major mutation G197del was detected in 30% (7 out of 22) of patients with FH. In the Slavic population of St. Petersburg, no major mutations were detected. Only five mutations were identified in two families, while 24 were found in isolated families. These data are indicative of the lack of a strong founder effect for FH in the St. Petersburg population.