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).     

Indirect immunofluorescence reaction of systemic and local humoral immunity in patients with inflammatory lung diseases. III. Secretory IgA antibodies to S. pneumoniae and H. influenzae autostrains

In acute pneumococcal infection with the clinical picture of acute bronchitis or the exacerbation of chronic bronchitis 88-93% of patients showed the formation of secretory IgA to S. pneumoniae autostrains, i.e. a high correlation between the occurrence of these bacteria in the sputum and the local immune response of the body. The characteristic feature of antipneumococcal secretory IgA is their earlier, more intensive and less prolonged formation in comparison with that of serum antibodies. During the exacerbation of chronic bronchitis only in 28% of the patients secretory IgA to H. influenzae autostrains and low correlation between the formation of secretory and serum antibodies were detected.     

Development of antibodies against the putative proteinase maturation protein A in relation to pneumococcal carriage and otitis media

The putative pneumococcal proteinase maturation protein A is a potential pneumococcal vaccine candidate. We examined serum antipneumococcal proteinase maturation protein A antibodies at 6, 12, 18 and 24 months of age, and showed that the age-related development of antipneumococcal proteinase maturation protein A antibodies is associated with pneumococcal contacts. A higher antipneumococcal proteinase maturation protein A antibody concentration at 18 months of age tends to predict for a lower risk of pneumococcal acute otitis media in the following 6 months (relative risk: 0.84, 95% confidence interval: 0.62-1.13).     

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.     

HBe antigen and its antibodies in HBsAg carriers in various regions of the USSR

A total of 300 blood serum samples, containing HBsAg and obtained from donors in three regions of the USSR (the RSFSR, the Uzbek SSR and the Moldavian SSR) differing in the level of HBsAg carriership, were studied for the presence of HBeAg and antibodies to this antigen in the passive hemagglutination (PHA) test and in the enzyme immunoassay (EIA). The occurrence of HBeAg was found to depend on the level of HBsAg carriership in the region. Thus, according to the EIA results, in Gorky, Kishinev and Tashkent HBeAg was detected, respectively, in 5.5%, 12.3% and 13.3% of serum samples, the level of HBsAg carriership in these cities being, according to the results of the PHA test, 1.4%, 5.0% and 9.0%. As shown by the results of EIA, the occurrence of HBeAg increased with the rise of the titer of HBsAg, while regarding the occurrence of antibodies to HBeAg the reverse relationship was observed.     

The indices of antipneumococcal immunity in children with chronic pneumonia

In 76 children with chronic pneumonia the levels of serum antibodies to pneumococcal capsular polysaccharide antigens (serotypes 1, 3, 6B, 8, 9N, 15F, 23F), O-polysaccharide and pneumococcal protein somatic antigens were determined by ELISA techniques. The study showed that in sick children the content of antipneumococcal antibodies in the blood increased with age. No correlation between the content of total immunoglobulins and that of antipneumococcal antibodies in the blood of the patients was established, but a sharp decrease in the concentration of antibodies was registered in a child with hypoglobulinemia. No increase in the level of antibodies to pneumococcal antigens was observed in cases of the exacerbation of Pneumococcus-induced inflammatory process in the lungs.     

Impaired antipneumococcal antibody production in patients without spleens.

Fifteen splenectomised and 15 normal subjects were studied, in absence of any intentional immunisation, for pokeweed mitogen induced synthesis of antipneumococcal capsular polysaccharide antibodies in vitro by peripheral blood mononuclear cells. Results showed that removal of the spleen had caused a persistent immune deficiency of circulating B cells capable of synthesising IgM antipneumococcal capsular polysaccharide. In vitro synthesis of polyclonal IgM and IgG by peripheral blood mononuclear cells of subjects without spleens was also depressed. These defects were due to an abnormality of the B cell compartment. These data are evidence of the major role of the spleen in the control and production of a consistent part of pokeweed mitogen responsive circulating B cells and add another facet to the complex immune dysfunction of splenectomised subjects. The findings, moreover, may help in understanding the susceptibility of splenectomised people to pneumococcal sepsis and the delayed and impaired antibody response to pneumococcal vaccine.     

The epidemic process of an acute streptococcal respiratory infection in large organized collectives of children

The study of the specific features of the development of the epidemic process of scarlet fever, tonsillitis, and acute respiratory diseases (ARD) in two large organized groups of children revealed the presence of some differences which depended on the character of prophylactic measures taken in these groups. Thus, in the absence of prophylaxis with bicillin a pronounced increase in the level of carriership, accompanied by an increase in the infective capacity of carriers, was noted. This resulted in a high level and unfavorable dynamics of morbidity in scarlet fever, tonsillitis, and ARD. On the contrary, the use of prophylaxis with bicillin ensured the stability of the level of carriership, while the infective capacity of carriers was not pronounced. At the same time a rise in ARD morbidity was insignificant, and morbidity in scarlet fever and tonsillitis was reduced to nil.     

Effect of vaccination against pneumococcal infection in children with type 1 diabetes mellitus

Vaccination with polysaccharide pneumococcal vaccine "Pneumo 23" (Sanofi Pasteur, France) was performed in 31 children with type 1 diabetes mellitus (DM1) as well as in 19 children with respiratory tract diseases (asthma, chronic pneumonia), which formed comparison group. Fourty-three unvaccinated children with DM1 were included in the control group. Dynamics of IgG levels to mixture of pneumococcal polysaccharides (PS) included in the vaccine as well as to PS of serotypes 3, 6B, 9N, 23F, and to cell wall polysaccharides of Streptococcus pneumoniae were assessed. Using ELISA method, significant increase of IgG levels to mixture of PS and to PS of pneumococcal serotype 3 was detected. Although intensity of immune response to vaccination in children with respiratory diseases was significantly higher compared to children with DM1 (mean geometric titer of antibodies, proportion of patients with high antibody titers, and with 4-fold seroconversion). Development of methods to strengthen immune response in children with DM1 vaccinated against pneumococcal infection is required.     

Role of spleen in immune response to polyvalent pneumococcal vaccine.

The immune response of lymphocytes to subcutaneously administered pneumococcal vaccine was studied in five patients without spleens and in five healthy subjects. Seven days after immunisation circulating B cells synthesising IgG antipneumococcal capsular polysaccharides (anti-PCP) appeared in both groups. Twenty one days after vaccination this B cell population had disappeared and a B cell subset which secreted IgM and IgG anti-PCP in the presence of pokeweed mitogen was detected in the normal but not in the splenectomised subjects. In the splenectomised group polyclonal IgM synthesis induced by pokeweed mitogen was defective. It was concluded that the early events of the immune response to PCP may be mediated by lymph nodes but that, later, the spleen acquires a central role in producing lymphocyte subsets capable of synthesising specific antibodies and that this might explain the increased sensitivity of splenectomised subjects to pneumococcal infection.     

Monthly dynamics of the epidemic process in viral hepatitis B

Monthly fluctuations in the number of registered cases of acute viral hepatitis B and HBsAg carriership have been studied. The study has revealed that, similarly to other infectious diseases, viral hepatitis is characterized by monthly fluctuations in the intensity of the epidemic process. Such fluctuations are characteristic of all known clinical forms of this infection; they are determined by the specific pathogenetic features of the process and by the ways of the transfer of the virus. The vernal rise of the infection is explained by activation of the manifest and asymptomatic chronic variants of the infectious process and, as the consequence of a rise in the number of asymptomatic cases, by a higher incidence rate of post-transfusion hepatitis infection. The autumnal rise of the infection results from the action of natural factors contributing to the transfer of the virus. Both rises are interrelated and interdependent. The seasonal fluctuations of the epidemic process should be taken into consideration when planning and implementing prophylactic and epidemic-control measures.     

Antibodies to the infective agents of opportunistic infections in blood of patients with hemoblastosis complicated with pneumonia

The examination of 112 hematological patients with diagnosed acute and chronic leucosis, lymphoma, myeloma, anemia, melanoma and other diseases revealed not a single subject among these examinees in whom no markers of opportunistic infections were detected. Low titers of antibodies to Pneumocystis carinii, cytomegalovirus (CMV), Epstein-Barr virus (EBV) were noted in 42%, 46.4% and 40.2% of examinees, respectively. Markers of acute diseases, such as class IgM, IgG antibodies in high titers, as well as P.carinii, CMV, EBV antigens, were detected in 37.5%, 30.4% and 22.3% of patients of a hematological hospital. In the group of comparison (donors) these figures were, respectively, 15.3%, 2.4% and 6.9%. The signs of monoinfection were detected in 11.6% (pneumocystosis), in 10.7% (CMV infection) and in 14.3% (EBV infection), while the markers of two infections, EBV infection and pneumocystosis, were detected in 9.8%, EBV and CMV infections in 11.6%, pneumocystosis and CMV infection in 14.3%; mixed contamination with all three infective agents was detected in 12.5% of the patients.     

Antibodies to Streptococcus pneumoniae antigens in newborn infants

The levels of antibodies to capsular polysaccharide antigens of pneumococci (serotypes 1, 3, 6B, 8, 9N, 15F, 23F), C-polysaccharide and protein antigen of pneumococci in the blood sera of 38 newborn infants at the moment of their birth (umbilical blood) and on the 5th or 6th day of their life, in their mothers' blood sera, as well as in the colostrum and milk of 48 nursing women, have been studied by means of the enzyme immunoassay. The study showed that in the normal course of pregnancy antibodies to pneumococci were transferred transplacentally from the mother to the fetus. Though in most cases their content in the blood of newborn infants was lower than that in maternal blood, it exceeded the average level of antipneumococcal antibodies in children aged 3-12 months. In the milk of nursing mothers considerable amount of IgA antibodies to pneumococci was detected, which might be an additional protective factor with respect to pneumococcal infection in infants.     

Occurrence of Acute Upper Respiratory Diseases among Children as a Result of Infection by Herpes Simplex Virus

One hundred and twenty-one children showing symptoms of acute upper respiratory disease were bled during a period of nine months, from winter to summer, for detection of complement-requiring neutralizing (CRN) antibody against herpes simplex virus. Six of the cases, all from children under the age of 13 years, were unequivocally related to herpetic infection as evidenced by the presence of anti-herpes CRN antibody. During the same period, 144 other children who were normal healthy or suffering from unrelated non-febrile diseases were tested as controls; anti-herpes CRN antibody was not detected in any of them. Further, the age distribution of individuals with antibodies was compared between patients in the acute upper respiratory disease group and the control group. This analysis showed that approximately 5 to 7% of the acute upper respiratory diseases in the young children in this study would be attributed to herpetic infection.     

Population pattern of pneumococci with lower susceptibility to penicillin and prospects of antipneumococcal vaccination to control antibiotic resistance distribution

Large-scale antipneumococcal vaccination is followed by changes in the serotype composition and level of antibiotic resistance in pneumococci. The aim of the study was to evaluate the serotype composition and population pattern of pneumococci with lower susceptibility to penicillin before large-scale antipneumococcal vaccination. Among 260 Streptococcus pneumoniae strains isolated in the Russian Federation within 2003-2007, serotypes 23F (37.2%) and 19F (13.9%) were the most frequent ones. 19.3% of the isolates belonged to serogroup 6, 3.6% of the isolates each belonged to serotype 3 and serogroup 18, 4.9% of the isolates belonged to serotype 14 and 2.2% of the isolates belonged to serotype 19A. 66.8% of the isolates belonged to serotypes of the 7-valent conjugated pneumococcal vaccine, 67.3 and 82.1% of the isolates belonged to the 10- and 13-valent conjugated pneumococcal vaccines respectively. The isolates with lower susceptibility to penicillin were characterized by significant clonality and 56.9% of them belonged to 4 global clonal complexes (CC81, CC156, CC320 and CC315). Inclusion of the conjugated antipneumococcal vaccine to the National Vaccination Time-Table of the Russian Federation could promote lower levels of antibiotic resistance in pneumococci.     

Etiology of acute pneumonia occurring against a background of influenza and other acute respiratory viral infections

The etiology of acute pneumonia (AP) was studied in 229 patients who had the disease simultaneously with influenza (106 patients), other viral and mycoplasmal infections (48 patients), and without concomitant acute viral infections (75 patients). The use of the quantitative microbiological method and the indirect immunofluorescence test with autostrains or Streptococcus pneumoniae strains of serotypes 2, 3, and 6, prevailing in Leningrad in patients with acute inflammatory diseases of the lungs, made it possible to find out the pneumococcal etiology of AP in 95% of patients irrespective of the presence of acute respiratory viral infections. The etiological role of opportunistic bacteria was revealed in 13 AP patients (5.7%); in 2 of them the causative agent of AP was Staphylococcus aureus and in 11, various species of Gram-negative enterobacteria. The latter were the cause of complications in 8 cases of pneumococcal pneumonia.     

Seroprevalence of Fecal-Oral Transmitted Hepatitis A and E Virus Antibodies in Burkina Faso

Hepatitis A virus (HAV) and hepatitis E virus (HEV) infections occur chiefly as a result of unhygienic conditions. The purpose of this study was to assess the seroprevalence of antibodies to both viruses in central Burkina Faso in the absence of a recorded hepatitis epidemic. Serum samples from 178 blood donors (131 males and 47 females) and from 189 pregnant women were collected from November 2010 to March 2012, at blood banks and medical centers in Burkina Faso. An immunochromatography test was used to screen for Anti-HAV IgM and IgG in a subgroup of 91 blood donors and 100 pregnant women. The seroprevalence of anti-HAV IgG was 14.3% [CI95, 7.1–21.4%] for all blood donors and 23% [CI95, 14.8–31.2%] for pregnant women. Anti-HEV IgG were detected using the ELISA kits Dia.pro and Wantai and were found in 19.1% [CI95, 13.3–24.9%] of the blood donors and 11.6% [CI95, 7.1–16.2%] of the pregnant women. The seroprevalences of anti-HAV and anti-HEV IgGs did not differ significantly between men and women blood donors. Anti-HAV IgM was detected in 3.3% of the blood donors and in 2% of the pregnant women. These findings for asymptomatic individuals indicate that the HAV and HEV circulate at low but significant levels. This is the first evaluation of the acute hepatitis virus burden in Burkina Faso and the underlying epidemiologic status of the population.     

Etiology of acute bronchitis in adults

A total of 126 adult patients with acute bronchitis were subjected to microbiological, virological and immunological examination. Influenza and other acute respiratory viral infections were detected in 104 (82.5%) cases of acute bronchitis. The results of microbiological examination and the study of local and systemic immunity showed that in 94.4 +/- 2.6% of the patients the development of acute bronchitis was linked with the appearance of acute pneumococcal infection irrespective of the presence, or absence, of virologically and serologically confirmed acute viral or mycoplasmal infections.