Pneumococcal Infections In Children Research Articles

Pneumococcal infections in children with sickle cell disease before and after pneumococcal conjugate vaccines

AbstractChildren with sickle cell disease (SCD) are at increased risk of invasive pneumococcal disease (IPD). Over 25 years, the Georgia Emerging Infections Program/Centers for Disease Control and Prevention Active Bacterial Core Surveillance network identified 104 IPD episodes among 3707 children with hemoglobin SS (HbSS) or HbSC aged <10 years, representing 6% of IPD in Black or African American children residing in Metropolitan Atlanta (reference population). Children with IPD and HbSS/SC were older than those with IPD in the reference population (P < .001). From 1994-1999 to 2010-2018, IPD declined by 87% in children with HbSS aged 0 to 4 years, and by 80% in those aged 5 to 9 years. However, IPD incidence rate ratios when comparing children with SCD with the reference population increased from 20.2 to 29.2 over these periods. Among children with HbSS and IPD, death declined from 14% to 3% after 2002, and meningitis declined from 16% to 8%. Penicillin resistance was more prevalent in children with SCD before 7-valent pneumococcal conjugate vaccine (PCV7) licensure. After 2010, all IPD serotypes were not included in the 13-valent PCV (PCV13). Within 3 years of vaccination, the effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) against non-PCV13 serotypes included in PPSV23 plus 15A/15C was 92% (95% confidence interval, 40.8- 99.0, P = .014; indirect-cohort effect adjusted for age and hydroxyurea). PPSV23 would cover 62% of non-PCV13 serotype IPD in children with SCD, whereas PCV15, PCV20, and PCV21/V116 (in development) could cover 16%, 51%, and 92%, respectively. Although less frequent, IPD remains a life-threatening risk in children with SCD. Effective vaccines with broader coverage could benefit these children.

Противопневмококковая иммунизация у детей раннего возраста с хронической сердечной недостаточностью

Aim: To determine the coverage, efficacy and tolerability of pneumococcal vaccination in young children with cardiovascular disease associated with chronic heart failure. Design: Retro- and prospective randomized comparative study. Materials and methods. The study included 250 patients at the age of 2 months to 5 years with confirmed chronic cardiac failure caused by cardiomyopathy or congenital heart disorder. Within the scope of a specialised laboratory and instrumental examination, all children underwent an assessment of specific immunoglobulin (Ig) levels to the most common pneumococcal serotypes (1-5, 6B, 7F, 8, 9N, 9V, 10A, 11A,12F, 14, 15B, 17F, 18C, 19F, 19A, 20, 22F, 23F, 33F) using VaccZyme Anti-PCP IgG test system. During consultations and vaccination schedule development, pneumococcal vaccination coverage and the reasons for long-term medical exemptions or refusals were analysed. Provided the primary disease was stable, there were no contraindications and a parent gave their consent, patients were vaccinated with 13-valent pneumococcal conjugate vaccine (PCV13). Results. When questioning the parents of patients, it was revealed that before admission to the department, only 97 (38.8%) patients received at least 1 dose of pneumococcal vaccine, while the remaining 153 (61.2%) were not vaccinated. During hospitalization, 65 (42.5%) of 153 unvaccinated patients under 5 years of age who had not received a single pneumococcal vaccine received the first dose (V1) of PCV13; of 97 children vaccinated, 20 (20.6%) received a second dose, 18 (18.6%) — pneumococcal booster. There was a significant difference in the levels of antibodies to Streptococcus pneumoniae between the group of patients who received a full course of immunization according to age and the group of unvaccinated children: 108.1 ± 58.4 vs. 12.14 ± 7.8 mg/l (p &lt; 0.05). In children with an incomplete course of vaccination, the levels of specific IgG to pneumococcal serotypes were lower. In groups of children who received only one dose of the vaccine in the first or second year of life, they amounted to 42.2 ± 11.7 and 40.2 ± 16.2 mg/l, respectively. Children who received at least two doses of vaccine without revaccination (starting before 12 months) had a relatively higher level of 68.2 ± 6.3 mg/L. But, despite a clear trend, there was no significant difference between these groups in our study. In the post-vaccination period, no serious complications were recorded in the examined children. Conclusion. Vaccination against pneumococcal infection in children with chronic heart failure is effective, safe and should be carried out as close as possible to the schedule of the national vaccination calendar, with a limited set of contraindications. Keywords: vaccination, 13-valent pneumococcal conjugate vaccine, immunoglobulin G, chronic heart failure.

Federal Clinical Guidelines on Vaccination of pneumococcal infection in children and adults

Federal Clinical Guidelines on Vaccination of pneumococcal infection in children and adults

Vaccination against pneumococcal infections in children with chronic heart failure

In current conditions, the most effective method of preventing pneumococcal infections (PI) is vaccination, which can significantly reduce the incidence and mortality from pneumococcus and reduce the level of antibiotic resistance. The use of pneumococcal conjugate vaccines has reduced the incidence of invasive PIs in vaccinated children and unvaccinated populations. This is especially true for children with severe somatic pathology, including those with various forms of heart failure (HF). The data show that vaccination of sick HF children can be a clinically effective intervention to improve the treatment results of circulatory failure and improve patients’ quality of life. However, questions regarding the optimal timing of vaccination of sick children with heart failure, dose, frequency and strategies of vaccine introduction still need to be resolved. Data on the pathophysiology of cardioprotection provision during effective vaccination against PI, influenza and COVID-19 in cardiac pathology are summarized. The authors recommend providing conditions for effective vaccine prevention of PI in children with heart failure.

Population-Based Surveillance of Pneumococcal Infections in Children with Sickle Cell Disease before and after Prevnar 7® and Prevnar 13® Licensure: Implications for Expanded Vaccination

Before prophylactic antibiotic use, approximately 1/10 children <5 years old with sickle cell disease (SCD) developed invasive pneumococcal disease (IPD) with a high risk of meningitis and death. Although the emergence of penicillin-resistance in IPD threatened benefits of penicillin prophylaxis, after licensure of the 7-valent pneumococcal polysaccharide vaccine (PCV7) in 2000, IPD rates in children with SCD decreased by over 2/3. In 2010, PCV13 (serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 19A, 19F, 18C, 23F) was licensed in children, and in 2021, two additional conjugated vaccines were approved for use in adults: PCV15 (VAXNEUVANCE®, PCV13+: 22F, 33F) and PCV20 (PREVNAR20®, PCV13+: 8, 10A, 11A, 12F, 15B, 22F, 33F). IPD rates in children with SCD over 24 years in Atlanta were evaluated to describe trends in age of infection, frequency of antibiotic resistance, non-vaccine IPD serotype distribution after vaccine licensures, and estimates for serotype coverage by newer vaccines. IPD among children with SCD, ages 0 to 4 years and 5 to 9 years, residing in the Metropolitan area of Atlanta, Georgia, USA, from 1/1/1994 through 7/31/2018, were compared to the general population. The Centers for Disease Control and Prevention (CDC)-funded Georgia Emerging Infections Program (GA EIP) Active Bacterial Core Surveillance network included initially 8 counties in 1994 and from 1997 onward, 20 counties (total populations of approximately 3.8 and 5.1 million, respectively). Two registries of patients with SCD seen at least once at one of 3 pediatric hospitals serving the region were merged and matched with GA EIP data. The serotyping and antibiotic susceptibility testing were conducted at the CDC. The study was approved by the Emory University Institutional Review Board. Data from 3 periods: pre PCV period (94-99), PCV7 period (00-09) and PCV13 period (10-18) were analyzed. Compared to the pre PCV period, overall, IPD rates decreased in children with SCD vs 91% in the RP for 0-4 years; and 80% in children with SCD vs 78% in the RP for 5-9 years (table1). The difference in IPD rates between patients with SCD and the general population increased over time: pre PCV period, relative risk (RR)=24.22 (95 % Confidence Interval [CI] 17.43,32.88), P<.001; PCV 7 period, RR=32.17 (95 %CI 22.17,45.37), P<.001; PCV 13 period, RR=39.18 (95 %CI 22.35,64.69) P<.001. Meningitis and deaths from IPD decreased significantly in all populations examined but remained significantly higher in patients with SCD compared to RP (table 2). The mean age at IPD diagnosis for the 3 periods examined increased both in SCD and in the RP. For those with SCD (n=50), pre-PCV7 period mean age was :2.7 standard deviation (+/-) 2.3 years; for the PCV 13 period: n=19; 3.7 years +/-2.2 years p= 0.0877; for the RP: Pre-PCV period: n=1025; 1.3 +/-1.6 years; PCV 13 period: n=213; 2.2 +/-2.3 years. Overall absolute IPD rates declined for all age groups examined (table 1). Prior to PCV7 licensure, IPD in patients with SCD were significantly less likely to be penicillin susceptible (MIC <0.06 µg/mL) compared to the RP: 41.9% (18/43) vs 60.0% (476/793) RR=0.70 (95% CI 0.49,1.00), p=0.025. This difference was no longer present after PCV licensure (PCV 13 period , SCD 52.9% [9/17], vs RP 48.6% [70/144]). Non PCV serotypes IPD rates increased after PCV7 licensure but remained stable after PCV13 licensure; 16% of non PCV13 serotypes during all time periods are included in PCV15, whereas PCV20 may cover between 29% and 50% depending on related serotypes cross protection (table3). Although significantly less frequent compared with pre-PCV-era, IPD can be severe in patients with SCD. Increase in IPD age was seen in both SCD and RP. Lower rates of penicillin non-susceptibility may may reflect lower exposure to penicillin prophylaxis. Newer vaccines may offer expanded coverage for children with SCD. Ongoing surveillance will help determine their effect. Vaccines that cover all serotypes are needed. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

An initiative to improve pneumococcal immunization counseling in children with nephrotic syndrome.

BackgroundImmunization is essential in preventing life-threatening pneumococcal infections in children with nephrotic syndrome. An additional 23-valent pneumococcal polysaccharide vaccine (PPSV23) series is required for children with nephrotic syndrome. Despite current practice guidelines, many children with nephrotic syndrome do not receive PPSV23.MethodsOur nephrology clinic conducted a quality improvement project to improve the overall rate of PPSV23 counseling to more than 70% within a 12-month period by applying several targeted interventions to raise providers’ awareness, improve communication with primary care providers, and increase provider adherence. Data was collected from the electronic health record (EHR), and monthly performance was tracked via monthly control charts and overall immunization counseling rate charts.ResultsWe increased adherence to PPSV23 vaccination counseling from a baseline of 12 to 86%. The first intervention that effectively increased the vaccine counseling rate from 12 to 30% was improving a provider’s awareness of the PPSV23 literature and vaccine guidelines. Other interventions included regular performance reviews at division meetings, creating an immunization protocol, posting performance charts on the office bulletin board, and unifying vaccine recommendation templates. Lastly, specific and timely EHR reminders improved the total counseling rate from 52 to 86% and maintained adherence until the completion of the project.ConclusionBridging the knowledge gap in provider awareness and using specific EHR reminders can improve adherence to PPSV23 counseling in children with nephrotic syndrome. Such interventions could be applied to similar groups of immunocompromised patients in whom additional vaccines are indicated.Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary information. Supplementary InformationThe online version contains supplementary material available at 10.1007/s00467-021-05305-3.

Review on Pneumococcal Infection in Children.

Childhood pneumococcal infection is a growing concern among paediatricians especially, in countries where there is no routine vaccination program against Streptococcal pneumoniae. The disease is associated with significant morbidity and mortality in young children particularly those who are under the age of two years. Its main virulent factors include polysaccharide capsule, autolysin, pneumolysin, choline-binding Protein A, the higher chance for genetic transformation, and the presence of pilli that facilitate enhanced binding of bacteria to host cellular surfaces. More severe and invasive pneumococcal infections are seen in children with immunodeficiencies, hypofunctional spleen, malnutrition, chronic lung disease and nephrotic syndrome. The disease spectrum includes a range of manifestations from trivial upper respiratory tract infections to severe invasive pneumococcal disease (PD). The basis of diagnosis is the isolation of bacteria in the culture of body fluids including blood. Antibiotics are best guided by sensitivity patterns and the emergence of resistance is a growing concern.

Can prophylactic antibiotics help to prevent pneumococcal infection in children with sickle cell disease?

Can prophylactic antibiotics help to prevent pneumococcal infection in children with sickle cell disease?

Prophylactic antibiotics for preventing pneumococcal infection in children with sickle cell disease.

Sickle cell disease (SCD) is a group of inherited disorders that result in haemoglobin abnormalities and other complications. Injury to the spleen, among other factors, contribute to persons with SCD being particularly susceptible to infection. Infants and very young children are especially vulnerable. The 'Co-operative Study of Sickle Cell Disease' observed an incidence rate for pneumococcal septicaemia of 10 per 100 person-years in children under the age of three years. Vaccines, including customary pneumococcal vaccines, may be of limited use in this age group. Therefore, prophylactic penicillin regimens may be advisable for this population. This is an update of a Cochrane Review which was first published in 2002, and previously updated, most recently in 2017. OBJECTIVES: To compare the effects of antibiotic prophylaxis against pneumococcus in children with SCD receiving antibiotic prophylaxis compared to those without in relation to: 1. incidence of Streptococcus pneumoniae infection; 2. mortality (as reported in the included studies); 3. drug-related adverse events (as reported in the included studies) to the individual and the community; 4. the impact of discontinuing at various ages on incidence of infection and mortality. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, which is comprised of references identified from comprehensive electronic database searches and also two clinical trials registries: ClinicalTrials.gov and the WHO International Registry Platform (not in 2020 given access issues relating to Covid-19 pandemic). Additionally, we carried out hand searching of relevant journals and abstract books of conference proceedings. Date of the most recent search: 25 January 2021. All randomised or quasi-randomised controlled trials comparing prophylactic antibiotics to prevent pneumococcal infection in children with SCD with placebo, no treatment or a comparator drug. The standard methodological procedures expected by Cochrane were used. Both authors independently extracted data and assessed trial quality. The authors used the GRADE criteria to assess the certainty of the evidence. Six trials were identified by the searches, of which three trials were eligible for inclusion. A total of 880 children,who were between three months to five years of age at randomization were included. The included studies wereconducted in centres in the USA and in Kingston, Jamaica. In trials that investigated initiation of penicillin on risk of pneumococcal infection, the odds ratio was 0.37 (95% confidence interval 0.16 to 0.86) (two trials, 457 children) (low-certainty evidence), while for withdrawal the odds ratio was 0.49 (95% confidence interval 0.09 to 2.71) (one trial, 400 children) (low-certainty evidence). Adverse drug effects were rare and minor. Rates of pneumococcal infection were found to be relatively low in children over the age of five years. Overall, the certainty of the evidence for all outcomes was judged to be low. The results from the risk of bias assessment undertaken identified two domains in which the risk of bias was considered to be high, these were incomplete outcome data (attrition bias) (two trials) and allocation concealment (selection bias) (one trial). Domains considered to have a low risk of bias for all three trials were selective reporting (reporting bias) and blinding (performance and detection bias). The evidence examined was determined to be of low certainty and suggests that prophylactic penicillin significantly reduces risk of pneumococcal infection in children with homozygous SCD, and is associated with minimal adverse reactions. Further research may help to determine the ideal age to safely withdraw penicillin.

Efficacy and Effectiveness of the PCV-10 and PCV-13 Vaccines Against Invasive Pneumococcal Disease.

Pneumococcal conjugate vaccines (PCVs) (pneumococcal 13-valent conjugate vaccine [PCV-13] and pneumococcal 10-valent conjugate vaccine [PCV-10]) are available for prevention of pneumococcal infections in children. To determine the vaccine effectiveness (VE) of PCV-13 and PCV-10 in preventing invasive pneumococcal disease (IPD) and acute otitis media (AOM) in children <5 years. Systematic searches of Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and Cochrane. Eligible studies examined the direct effectiveness and/or efficacy of PCV-10 and PCV-13 in reducing the incidence of disease in healthy children <5 years. Two reviewers independently conducted data extraction and methodologic quality assessment. Significant effectiveness against vaccine-type IPD in children ≤5 years was reported for ≥1 dose of PCV-13 in the 3 + 1 (86%-96%) and 2 + 1 schedule (67.2%-86%) and for PCV-10 for the 3 + 1 (72.8%-100%) and 2 + 1 schedules (92%-97%). In children <12 months of age, PCV-13 VE against serotype 19A post-primary series was significant for the 3 + 1 but not the 2 + 1 schedule. PCV-10 crossprotection against 19A was significant in children ≤5 years with ≥1 dose (82.2% and 71%). Neither PCVs were found effective against serotype 3. PCV-13 was effective against AOM (86%; 95% confidence interval [CI]: 61 to 94). PCV-10 was effective against clinically defined (26.9%; 95% CI: 5.9 to 43.3) and bacteriologically confirmed AOM (43.3%; 95% CI: 1.7 to 67.3). Because of the large heterogeneity in studies, a meta-analysis for pooled estimates was not done. Both PCVs afford protection against pneumococcal infections, with PCV-10 protecting against 19A IPD, but this VE has not been verified in the youngest age groups.

The Effect of Selective and Mass Immunization Against Pneumococcal Infection on the Morbidity and Mortality due to Community-Acquired Pneumonia in Children Under 5 Years of Age

Background. It is required to perform estimation of epidemiological and cost efficacy (regarding morbidity rate) of mass routine vaccination against pneumococcal infection in Russian children and carried out earlier selective vaccination of children from high-risk groups on the basis of four-year experience. It is also important to estimate the rate of hospital admissions in this patient group, long-term and annual cycles, morbidity age and etiology structure, and mortality due to community-acquired pneumonia as one of the most common form of pneumococcal disease.The aimis to study the effect of selective and mass immunization against pneumococcal infection on the morbidity and mortality due to community-acquired pneumonia in children under 5 years of age. Methods.The analysis of communityacquired pneumonia morbidity (in 2003–2018) and mortality due to pneumonias (in 2003–2018) in children under the 14 years old in Perm was carried out. Serotypes of circulating pneumococcus, etiology of community-acquired pneumonias and immunization cost efficacy (direct expense on health care) were further studied. The analysis of study indexes was carried out following selective (vaccination of at-risk children in 2011–2014) and mass (vaccination of infants in 2015–2018) immunization strategies. Results. The morbidity rate of community-acquired pneumonias decreased by 4.0 times (from 267.0 to 66.7 for 1000) after performing selective vaccination (2011–2014) in at-risk children (frequently and chronically ill children). The morbidity rate of community-acquired pneumonias in non vaccinated children of the same group increased by 2.0 times (from 40.0 to 80.0 for 1000 non-vaccinated). The prophylactic efficacy index was 46.0. Whereby the antibacterial index among vaccinated frequently and chronically ill children was 0.11 on one child. This index has decreased by 2.6 times (from 0.11 to 0.04 on one child) in a year within the framework of prospective controlled randomized clinical study. The antibacterial index among non-vaccinated children of this group remained slightly the same: 0.09 and 0.12 respectively. During the selective vaccination the mortality rate among infants decreased by 2 times: long-term average index was 17.9 (2011–2014) against 35.2 (2003-2010) on 100 thousand children. Mass vaccination of infants against pneumococcal infection has reduced the incidence of community-acquired pneumonias among children under 2 years of age and has led to absence of multiple sites of pneumococcal infection in children’s organizations. It also has reduced the number of hospitalized children and achieved zero mortality due to pneumonias in infants by the third year of this immunization strategy implementation. The obtained results were achieved mainly due to circulation of 7 pneumococcal serotypes (6A, 6B, 9V, 14, 19A, 19F, 23F) in children under 5 years of age. The threshold level of vaccination against pneumococcal infection advancing morbidity and mortality due to pneumonias in children was specified. The strategy of mass vaccination of infants was cost-effective. Conclusion. The new data on epidemiological and cost efficacy of various immunization strategies against pneumococcal infection in children was obtained.

Epidemiological and economic efficiency of mass vaccinal prevention against pneumococcal infection in children compared with selective immunization at the example of community-acquired pneumonia

Aim. To study the epidemiological pattern of community-acquired pneumonias in children and the influence of mass vaccinal prevention on morbidity and mortality.&#x0D; Materials and methods. Vaccination of children against pneumococcal infection on the territory of a large industrial center of Western Urals was analyzed, influence of mass vaccination against pneumococcal infection on pneumonia morbidity and mortality in children was determined.&#x0D; Results. Mass vaccinal prevention of children of the first year of life against pneumococcal infection (vaccination volume 102 353.6 per 100 thousand children under 6) significantly influenced morbidity level regarding community-acquired pneumonias in the group of vaccinated children under 2 (1619.9 0.78 versus 15233.7 2.5 per 100 thousand in the group of unvaccinated, odds ratio and its confidence interval was 9.40 [95 % CI 8.4610.44]), on community-acquired streptococcal morbidity of children under 6 (r = 0.97; regression coefficient = 36.30, р 0.001; R2 = 91.0 %, significance F = 0.01 and possibility 95.0 %) and 5-fold decreased the mortality level (from 35.2 before vaccination started to 6.8 per 100 thousand) till its full absence in the third year of realization of this strategy. No analogous influence on the main manifestations of epidemiological process of community-acquired pneumonia was noted in case of selective immunization against pneumococcal infection among 25 year olds, belonging to high risk groups (vaccination volume 10 417.08 per 100 thousand children under 6).&#x0D; Conclusions. The strategy of mass vaccination of children of the first year of life was characterized by the greatest epidemiological and economic benefits. Economic efficiency taking into account vaccination costs in terms of 1000 of vaccinated children was 17.1 times higher and was equal to 8.3656 mln rub per 1000 inhabitants versus 0.4890 mln rub in case of selective immunization of high risk group children.

Can prophylactic antibiotics help to prevent pneumococcal infection in children with sickle cell disease?

Can prophylactic antibiotics help to prevent pneumococcal infection in children with sickle cell disease?

Invasive Pneumococcal Infections in Children with Nephrotic Syndrome in Bangladesh

Children with nephrotic syndrome are susceptible to invasive bacterial infections. In this study, we aimed to: (1) determine the pathogens associated with infections in children with nephrotic syndrome and (2) describe antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae to guide evidence-based treatment and prevention policies. From June 2013 to March 2015, we collected blood and/or ascitic fluid from children hospitalized with nephrotic syndrome and suspected bacterial disease in the largest pediatric hospital of Bangladesh. We cultured all samples and performed polymerase chain reaction (PCR) and immunochromatographic test on ascitic fluid for detection of S. pneumoniae. Pneumococcal isolates were tested for antibiotic susceptibility using disc diffusion and serotyped using Quellung reaction and PCR. We identified 1342 children hospitalized with nephrotic syndrome. Among them, 608 children had suspected bacterial disease from whom blood and/or ascitic fluid were collected. A pathogen was identified in 8% (48/608) of cases, 94% (45/48) of which were S. pneumoniae. Most (73%, 33/45) pneumococcal infections were identified through culture of blood and ascitic fluid and 27% (12/45) through immunochromatographic test and PCR of ascitic fluid. In total, 24 different pneumococcal serotypes were detected; 51% are covered by PCV10 (+6A), 53% by PCV13 and 60% by PPSV23. All pneumococcal isolates were susceptible to penicillin. Because S. pneumoniae was the primary cause of invasive infections, pneumococcal vaccines may be considered as a preventive intervention in children with nephrotic syndrome. Additionally, penicillin can be used to prevent and treat pneumococcal infections in children with nephrotic syndrome in Bangladesh.

Congenitally impaired pattern-recognition receptors in pathogenesis of pediatric invasive and recurrent pneumococcal infection

Here we review currently available data showing that innate immune signs predisposing to recurrent and invasive pneumococcal infections were identified in children. Streptococcus pneumoniae (pneumococcus) belongs to Grampositive bacteria being the major cause of morbidity and mortality in infants, especially in developing countries and in communities with low socioeconomic status. Due to the lack of anti-pneumococcal vaccination, the significant proportion of pneumococcus carriers develop non-invasive (pneumonia, otitis media, sinusitis) and severe invasive (bacteremia/septicemia, meningitis) pneumococcal infection. A great deal of diverse factors related to pneumococcus biological features (virulence factors) as well individualized host-specific immunity are implicated in efficient bacterial penetration across the mucous membranes. The TLR signaling system plays a crucial role in the human nonspecific defense upon the first encounter with the pathogen. Various TLRs comprise the first pattern recognition receptor fami ly ever described which sense ligands derived from the outer bacterial wall. The complement system is the ancient innate immunity component mainly involved in intravascular elimination of bacterial agents. In addition, the complement proteins serve as a bridge between innate and adaptive immunity, ensuring optimal conditions for B- and T-cell maturation and differentiation. Because pneumococcus secretes the IgA protease, a local protective effects related to IgA antibodies might not be so prominent. Therefore, B-cell immunodeficiency and impaired complement system hold a lead place among congenital causes resulting in severe and recurrent pneumococcal infections in children. Thus, based on available data, we concluded that impaired B-cell function, the complement components deficiency as well as receptor-recognition receptors (TLR-2, -9, -4, MYD88 adapter protein, TLR cascade enzymes: IRAK4, NEMO, NOD-like receptors: NOD2, NLRP3; C-type lectins: MBL, Dextin-2, and, possibly, ficoline) play the most important role among congenital immunodeficiencies predisposing to invasive and recurrent pneumococcal infections play the most important role among congenital immunodeficiencies predisposing to invasive and recurrent pneumococcal infections, and should be used as a rationale for immunological surveillance and organizing immunogenetics screening in these patients.

Vaccine Prophylaxis of Pneumococcal Infections in Children under Conditions of Severe Flood in the Amur River Basin.

Background Pneumococcal infection being one of the dominant causes of acute respiratory diseases and exacerbation of chronic ones is a serious problem for human health and society. The flood in the Amur river basin in the summer of 2013 created a special zone and risk conditions for the formation of respiratory pathology in the Far-Eastern region of Russia. We aimed to give clinical and epidemiological assessment of the effectiveness of vaccination programs of respiratory viral and pneumococcal infections and generalization of regional experience in the organization of a set of measures aimed at their prevention in the postflood period in the Far-Eastern region. Methods The monitoring program includes children aged 2 to 5 years in the amount of 4988 with risk factors for pneumococcal infection. The pneumococcal conjugate vaccine Prevenar-13 was used for immunization. Data on the incidence of ARVI and pneumonia in children in pre- and postvaccination periods were to be recorded. The indicators and special criteria were used to assess the effectiveness of vaccination. To study the circulation of serovariants of pneumococcus in inflammatory diseases of the respiratory tract and nasopharyngeal carrier, bacteriological and molecular genetic methods (RT-PCR in the mode of multiprime detection) were used. Results Differences in the frequency and range of serovariants of circulating isolates of pneumococcus in the postvaccinal period and in unvaccinated children, elimination of a number of serotypes, and appearance of circulation of nonvaccinated strains were revealed. The incidence of acute respiratory diseases and pneumonia among the vaccinated population for 2 years in the region decreased by 2.5 times. The coefficient of effectiveness of vaccination according to the indicator of morbidity of children with pneumonia reaches 75-100% with direct dependence on the age of children (r=0.98). Conclusion Comparative statistical analysis revealed a high degree of effectiveness of regional programs with the methods of immunoprophylaxis of pneumococcal infections.

Changes in the pneumococcal vaccine serotypes in adult noninvasive pneumonia after the introduction of pneumococcal conjugate vaccination for children

Context:Although the incidence of invasive pneumococcal infections in children has decreased since the introduction of pneumococcal conjugate vaccines (PCVs), the appearance of serotype replacements has continued to increase.Aims:We examined the frequency of serotype replacements in adult cases of pneumococcal pneumonia. Furthermore, the transition in the coverage of vaccine serotypes (VTs) to non-VTs (NVTs) was also examined.Settings and Design:We investigated all confirmed cases of pneumococcal pneumonia in 303 adult patients admitted to Yamagata Saisei Hospital between April 2006 and March 2015.Materials and Methods:Pneumococcal serotypes were determined by testing for a specific type of antiserum using the capsular swelling method.Statistical Analysis Used:Chi-square tests were used to compare patient characteristics.Results:Annually, the number of admitted patients ranged from 24 to 43, with most of them being men (64.7% of the total patient cohort). Although many cases involved some underlying conditions, the rate of pneumococcal vaccination remained low. The average rate of multigeneration housing was high (37.6%). The rates of pneumococcal vaccine coverage declined since 2013 (7-valent PCV (PCV7), 18.5%; PCV13, 59.3%; and 23-pneumococcal polysaccharide vaccine (PPSV23), 66.7%) and were <50% for each vaccine (PCV7, 4.7%; PCV13, 32.6%; and PPSV23, 48.8%) in 2015. In addition, the VTs were replaced with NVTs in 2015 (48.8% vs. 51.2%).Conclusions:The frequency of NVTs in adult pneumococcal pneumonia increased in 2013, with the frequency exceeding that of the vaccine forms in 2015. Regular PCV vaccination of children and multigeneration housing seem to be associated with this reversed trend.

Nasal immunization with recombinant chimeric pneumococcal protein and cell wall from immunobiotic bacteria improve resistance of infant mice to Streptococcus pneumoniae infection.

Respiratory tract infections and invasive disease caused by Streptococcus pneumoniae in high-risk groups are a major global health problem. Available human vaccines have reduced immunogenicity and low immunological memory in these populations, as well as high cost as a public health strategy in poor communities. In addition, no single pneumococcal protein antigen has been able to elicit protection comparable to that achieved using protein-polysaccharide conjugate vaccines. In this context, chimeric pneumococcal proteins raise as potential good vaccine candidates because of their simplicity of production and reduced cost. The aim of this work was to study whether the nasal immunization of infant mice with the recombinant chimeric pneumococcal protein (PSFP) was able to improve resistance to S. pneumoniae, and whether the immunomodulatory strain Lactobacillus rhamnosus CRL1505 or its cell wall (CW1505) could be used as effective mucosal adjuvants. Our results showed that the nasal immunization with PSPF improved pneumococcal-specific IgA and IgG levels in broncho-alveolar lavage (BAL), reduced lung bacterial counts, and avoided dissemination of pneumococci into the blood. Of interest, immunization with PSPF elicited cross-protective immunity against different pneumococcal serotypes. It was also observed that the nasal immunization of infant mice with PSPF+CW1505 significantly increased the production of pneumococcal-specific IgA and IgG in BAL, as well as IgM and IgG in serum when compared with PSPF alone. PSPF+CW1505 immunization also improved the reduction of pneumococcal lung colonization and its dissemination in to the bloodstream when compared to PSPF alone. Our results suggest that immunization with PSPF together with the cell wall of the immunomodulatory strain L. rhamnosus CRL1505 as a mucosal adjuvant could be an interesting alternative to improve protection against pneumococcal infection in children.

Vaccine Prevention of Pneumococcal Infection in Children

Pneumococcal infection remains one of the leading reasons for infant mortality from vaccine-preventable infections. Today vaccination is the most effective way to prevent diseases caused by antibiotic-resistant pneumococci. In the article, authors present current approaches to vaccinal prevention of pneumococcal diseases. The plan of action for carrying out active immunoprophylaxis of pneumococcal infection is explained in detail for both healthy children and patients from risk groups for severe pneumococcal diseases development. The published work is based on key points of the guidelines of the Ministry of Health of the Russian Federation on vaccinal prevention of pneumococcal infection (developed and approved by the professional association of pediatricians «The Union of Pediatricians of Russia»).

Comparison of serological assays using pneumococcal proteins or polysaccharides for detection of Streptococcus pneumoniae infection in children with community-acquired pneumonia

The aim of this study was to compare the results of serological assays using pneumococcal proteins or polysaccharides for the detection of pneumococcal infection in childhood pneumonia. Serological assays measured IgG against eight pneumococcal proteins (Ply,CbpA,PspA1,PspA2,PcpA,PhtD,StkP-C,PcsB-N), C-polysaccharide [in the whole study population, n = 183], or 19 pneumococcal capsular polysaccharides (1,2,4,5,6B,7F,8,9 V,10A,11A,12F,14,15B,17F,18C,19F,20,23F,33F) [only in a subgroup of patients, n = 53] in paired serum samples of children aged <5 years-old hospitalized with clinical and radiological diagnosis of community-acquired pneumonia. We also performed an inhibition of binding test with the anti-capsular polysaccharide assay in order to confirm the specificity of the antibody responses detected. Invasive pneumococcal pneumonia was investigated by blood culture and PCR (ply-primer). Among 183 children, the anti-protein assay detected antibody response in 77/183(42.1%) patients and the anti-C-polysaccharide assay in 28/183(15.3%) patients. In a subgroup of 53 children, the anti-protein assay detected response in 32/53(60.4%) patients, the anti-C-polysaccharide assay in 11/53(20.8%) patients, and the anti-capsular polysaccharide in 25/53(47.2%) patients. Simultaneous antibody responses against ≥2 different capsular polysaccharides were detected in 11/53(20.8%) patients and this finding could not be explained by cross-reactivity between different serotypes. Among 13 patients with invasive pneumococcal pneumonia, the sensitivity of the anti-protein assay was 92.3%(12/13), of the anti-C-polysaccharide assay 30.8%(4/13), and of the anti-capsular polysaccharide assay 46.2%(6/13). The serological assay using pneumococcal proteins is more sensitive for the detection of pneumococcal infection in children with pneumonia than the assay using pneumococcal polysaccharides. Future studies on childhood pneumonia aetiology should consider applying serological assays using pneumococcal proteins.