Serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae strains isolated in Japan after introduction of the routine immunization program.

Pneumococcal vaccines have reduced the incidences of Streptococcus pneumoniae infections among children and adults, but a relative increase in the prevalence of non-vaccine serotypes has been reported. To follow the changing epidemiology of pneumococcal diseases, capsular serotyping and antimicrobial susceptibility testing was performed on 534 pneumococcal isolates obtained from a hospital in Japan after routine immunization was launched, between October 2014 and May 2016. Serotype distributions and antimicrobial susceptibilities were evaluated among the total patient population, and were compared by age and sample groups and by serotype group, respectively. Serotypes targeted by the 13-valent pneumococcal conjugate vaccine (PCV13) were identified in 14.6%, 44.5%, and 40.2% of the samples from the <5, 5-64, and ≥65 year age groups, respectively. The 23-valent pneumococcal polysaccharide vaccine serotypes (PPSV23) were identified in 42.4%, 68.2%, and 63.1% of the samples, respectively; whereas non-PCV13 serotypes or non-PPSV serotypes (NVT) comprised 46.8% of all isolates. Among NVT, strain 35B was the most frequently isolated, followed by 15A, particularly in sputum samples collected from children <5 years old. Meanwhile, serotype 3, which is targeted by the PCV13 and PPSV23, was the most prevalent among patients aged ≥65 and 5-64 years. Antimicrobial susceptibility testing revealed that 88.9% and 81.0% of serotype 35B was non-susceptible to penicillin and meropenem, respectively, and 89.4% of 15A was non-susceptible to penicillin. Our data suggest rapid effects of pneumococcal vaccines and progression of serotype replacement. Besides invasive potential, the increased prevalence of non-vaccine serotypes with highly non-susceptible to penicillin was a concern. Continuous monitoring of pneumococcal serotypes and antimicrobial susceptibility is necessary for developing optimal preventive strategies.

Evaluation of Haemophilus influenzae type b carrier status among children 10 years after the introduction of Hib vaccine in Brazil.

The aim of the present study was to assess the prevalence of Haemophilus influenzae type b (Hib) nasopharyngeal (NP) colonisation among healthy children where Hib vaccination using a 3p+0 dosing schedule has been routinely administered for 10 years with sustained coverage (> 90%). NP swabs were collected from 2,558 children who had received the Hib vaccine, of whom 1,379 were 12-< 24 months (m) old and 1,179 were 48-< 60 m old. Hi strains were identified by molecular methods. Hi carriage prevalence was 45.1% (1,153/2,558) and the prevalence in the 12-< 24 m and 48-< 60 m age groups were 37.5% (517/1,379) and 53.9% (636/1,179), respectively. Hib was identified in 0.6% (16/2,558) of all children in the study, being 0.8% (11/1,379) and 0.4% (5/1,179) among the 12-< 24 m and 48-< 60 m age groups, respectively. The nonencapsulate Hi colonisation was 43% (n = 1,099) and was significantly more frequent at 48-< 60 m of age (51.6%, n = 608) compared with that at 12-< 24 m of age (35.6%, n = 491). The overall resistance rates to ampicillin and chloramphenicol were 16.5% and 3.7%, respectively; the co-resistance was detected in 2.6%. Our findings showed that the Hib carrier rate in healthy children under five years was very low after 10 years of the introduction of the Hib vaccine.

Evaluation of Haemophilus influenzae type b carrier status among children 10 years after the introduction of Hib vaccine in Brazil

The aim of the present study was to assess the prevalence of Haemophilus influenzaetype b (Hib) nasopharyngeal (NP) colonisation among healthy children where Hib vaccination using a 3p+0 dosing schedule has been routinely administered for 10 years with sustained coverage (> 90%). NP swabs were collected from 2,558 children who had received the Hib vaccine, of whom 1,379 were 12-< 24 months (m) old and 1,179 were 48-< 60 m old. Hi strains were identified by molecular methods. Hi carriage prevalence was 45.1% (1,153/2,558) and the prevalence in the 12-< 24 m and 48-< 60 m age groups were 37.5% (517/1,379) and 53.9% (636/1,179), respectively. Hib was identified in 0.6% (16/2,558) of all children in the study, being 0.8% (11/1,379) and 0.4% (5/1,179) among the 12-< 24 m and 48-< 60 m age groups, respectively. The nonencapsulate Hi colonisation was 43% (n = 1,099) and was significantly more frequent at 48-< 60 m of age (51.6%, n = 608) compared with that at 12-< 24 m of age (35.6%, n = 491). The overall resistance rates to ampicillin and chloramphenicol were 16.5% and 3.7%, respectively; the co-resistance was detected in 2.6%. Our findings showed that the Hib carrier rate in healthy children under five years was very low after 10 years of the introduction of the Hib vaccine.

Chinese medicine syndrome distribution of chronic hepatitis B virus carriers in immunotolerant phase.

OBJECTIVE: To explore Chinese medicine (CM) syndrome distribution of chronic hepatitis B virus (HBV) carriers in immunotolerant phase (ITP). METHODS: One hundred and eighty-five chronic HBV carriers in ITP, seen in the Third Affiliated Hospital of Sun Yat-sen University from May 2009 to December 2010, were admitted in an observational study under the guidance of CM. Patients' CM symptoms and signs, demographics, liver biochemistries, and qualitative HBV DNA were recorded in the questionnaires. CM syndromes were then differentiated to 15 detailed types and analyzed by generalization. Lastly, the location, pathogenic factors and nature of the disease were also assessed. RESULTS: When CM syndrome patterns were differentiated to 15 types, there were 27 (15%) no syndrome cases, 94 (50%) single syndrome cases and 64 (35%) compound syndromes cases. The main detailed syndromes included Liver (Gan)-qi depression (LQD), Kidney (Shen)-qi deficiency (KQD), Spleen (Pi)-qi deficiency (SQD) and Kidney-yang deficiency (KYAD). After CM syndromes generalized to five types, their frequency was Spleen-Kidney deficiency (SKD)>LQD>inner dampness-heat retention (IDHR)>Liver-Kidney deficiency (LKD)>blood stasis blocking collateral (BSBC). SKD and LQD occupied 64%. The disease location included Liver, Gallbladder (Dan), Spleen, Stomach (Wei) and Kidney. The pathogenic factors were mainly qi stagnation, qi deficiency, yang deficiency, concurrently dampness-heat and blood stasis. The deficiency syndrome was more than excess syndrome in its nature. CONCLUSIONS: Most of chronic HBV carriers in ITP have their CM syndrome, and the most common types are SKAD, LQD. This study suggests that the natural history may be improved through breaking the state of immune tolerance or shorten the time of ITP by strengthening Spleen-Kidney and reliving Liver qi.

Changes in Streptococcus pneumoniae serotype distribution in invasive disease and nasopharyngeal carriage after the heptavalent pneumococcal conjugate vaccine introduction in Bogotá, Colombia.

BACKGROUND: In Bogotá, the Heptavalent Conjugate Vaccine (PCV7) was introduced into childhood immunization schedule since 2009. The aim of this study was to assess the changes in serotype distribution and penicillin susceptibility of Streptococcus pneumoniae isolates recovered from nasopharyngeal samples and invasive disease among children living in Bogotá, before and after PCV7 introduction. METHODS: Nasopharyngeal swabs were collected from healthy children aged between 12 and 18 months of age before (years 2005-2006) and after (2011) PCV7 introduction. Identification of S. pneumoniae was performed by multiplex PCR. Serotype was determined by PCR and Quellung reaction. Susceptibility to penicillin, ceftriaxone, trimethoprim-sulfamethoxazole, chloramphenicol, tetracycline and erythromycin was evaluated. In addition, distribution of serotypes and antimicrobial susceptibility before and after vaccine introduction among invasive isolates recovered from children ≤2 years old living in Bogotá was analyzed. RESULTS: Prevalence of pneumococcal nasopharyngeal carriage declined from 55.7% (137/246) in unvaccinated to 44.2% (87/197) (p=0.01) in vaccinated children. The proportion of children carrying PCV7 serotypes decreased from 23.6% (58/246) to 7.6% (15/197) (p<0.001). The decrease was counterbalanced by an increase in the proportion of non-PCV7 serotypes. The most prevalent among emerging serotypes were 15A, 15B, 15C, 11A and 35B. Among IPD isolates, PCV7 serotypes decreased from 69.1% (235/340) in 2005/2009 to 38.0% (32/84) in 2010/2011 (p<0.001). The increase of non-PCV7 serotypes was significant. Resistance to penicillin among invasive isolates recovered from meningitis decreased from 41.1% (30/73) in the pre-vaccine period to 14.2% (2/14) in post-vaccine period (p=0.02). CONCLUSIONS: A decrease in the prevalence of pneumococcal nasopharyngeal carriage following the introduction of PCV7 vaccine, have been overshadowed by an important surge in the prevalence of non-PCV7 serotypes. Systematic surveillance combining nasopharyngeal carriage surveys and IPD detection could help in evaluating the impact of conjugate vaccines.

Hepatitis B surface antigen carrier rate in unvaccinated and vaccinated children with thalassaemia major at Bahawal Victoria Hospital, Bahawalpur, Pakistan.

Screening of blood reduces but does not eliminate the risk of hepatitis B virus (HBV) infection in multi-transfused thalassaemia patients. This study was done to evaluate efficacy of HBV vaccination on hepatitis B virus surface antigen (HBsAg) carrier rate in children with thalassaemia major receiving multiple blood transfusions. In a cohort study conducted at a hospital in Bahawalpur, Pakistan, during 2009-10, children with thalassaemia major aged < 60 months who received more than 24 blood transfusions and were HBsAg negative at the time of first blood transfusion were included. Of 196 unvaccinated children, the seropositive rate was 12.2%; while among 218 children vaccinated during the first year of life via the Pakistan Expanded Programme on Immunization, the seropositive rate was only 0.9%. The HBV vaccine was highly effective in reducing the HBsAg carrier rate in hildren with thalassaemia aged < 5 years.

Immunisation against Theileria parva in eastern Zambia: influence of maternal antibodies and demonstration of the carrier status.

Immunisation of calves by the infection and treatment method (I & T) has been extensively used in the eastern province of Zambia to control East Coast fever (ECF), a protozoan tick-borne disease. This paper presents the results of a field longitudinal study, which included a total of 148 Angoni calves. After immunisation against ECF, they were monitored for a full rainy season, coinciding with the main peak of activity of the vector of Theileria parva, the tick Rhipicephalus appendiculatus. Dysimmunisation (acute reaction generated by I & T immunisation), seroconversion and mortality are among the parameters recorded. The effect of maternal antibodies on these parameters was analysed and also studied in experimental conditions on two calves. Before immunisation, young calves had a higher seroprevalence than older animals (maternal antibodies) but their post-immunisation seroprevalence was lower. There was no evidence that their immunoprotection was weaker but this indicates that the post-immunisation seroconversion is probably not a reliable tool to monitor the efficacy of calf immunisation. The carrier state of cattle after immunisation was investigated in experimental conditions on three bovines whereas in the field, the infection prevalence in the ticks was estimated using the relation between the tick burden and the T. parva contacts with the calves. The ability of larval and nymphal R. appendiculatus ticks to pick-up T. parva from carriers and to transmit it to naïve animals after moulting was assessed. It was found that both instars are able to transmit clinical and lethal ECF but that the prevalence of T. parva infection in nymphs is much lower than in adults, confirming the primary role of adults in the transmission of ECF in endemic conditions. Similar results were obtained from the field whereby the ECF peak corresponds with the peak of adult R. appendiculatus activity. The infection prevalence in the ticks was however much lower in the field than in experimental conditions indicating that an important proportion of them feed on alternative hosts. Old ticks seemed to have lost part of their infectivity.

The first five years of universal hepatitis B vaccination in South Africa: evidence for elimination of HBsAg carriage in under 5-year-olds.

South Africa implemented a vaccine against hepatitis B virus (HBV) into the Expanded Programme on Immunisation (EPI) in April 1995. The HBV vaccine is given at 6, 10, and 14 weeks, in parallel with OPV, DTP and Hib vaccines. This study assessed the impact of universal childhood HBV vaccination programme in reducing HBsAg carriage, in the first five years (1995--1999) since its implementation. In parallel, we investigated the current burden of HBV infection in mothers of vaccinees and the adult general population. A total of 598 babies (mean age=23.3 months) who received 3 doses of 1.5 microg/0.5 ml Hepaccine-B (Cheil) were recruited from the Northern Province (one of the nine provinces in South Africa). HBsAg, anti-HBs, anti-HBc, HBeAg and anti-HBe were tested using the IMx or Axsym kits (Abbott Laboratories). PCR assays were performed following established protocols. The overall seroprotection rate (i.e. anti-HBs titre> or =10 mIU/ml) was 86.8% (519/598) in vaccinated babies, while 13.2% had anti-HBs levels<10 mIU/ml. Seroprotection rates and geometric mean titres (GMT) decreased significantly with increasing age, possibly reflecting waning anti-HBs titre over time. Total HBV exposure (positive for either HBsAg, anti-HBs, or anti-HBc) was 31.0% (58/187) in mothers of vaccinees and 40% (72/180) in the adult general population. HBsAg carrier rate was virtually similar in both groups (3.2% in mothers of vaccinees vs. 3.3% in the general population). Against this background, no vaccine failures resulting in HBsAg and HBV DNA positivity were seen in vaccinated babies, including 6 babies born to HBsAg positive carrier mothers (one carrier mother was positive for HBeAg and HBV DNA). However, 0.9% (5/582) babies, aged between 8--11 months, tested positive for anti-HBc, all of whom had anti-HBs titres>10 mIU/ml and were negative for HBV DNA. Anti-HBc positivity was probably maternal in origin, or may represent sub-clinical averted HBV infections. It can be concluded that the HBV vaccine is highly effective within the framework of the South African EPI and already shows a positive impact in the elimination of HBsAg carrier rate in children<5 years.

Impact of hepatitis B immunisation as part of the EPI.

Since 1992, hepatitis B vaccine has been an integrated part of Thailand's expanded programme on immunisation (EPI). Based on the data from five representative provinces, we have evaluated its impact on the countrywide prevalence of HBV infection and carrier rate. The population studied comprised 400-488 healthy and immuno-competent, subjects per area. The subjects' ages ranged from 6 months to 18 years. We examined their sera for viral hepatitis markers using commercially available test kits and established the coverage rate of hepatitis B vaccination after its inclusion into the EPI to be 71.2-94.3%. The number of individuals undergoing the complete course of vaccinations had increased four-fold. Consequently, only 0.7% of the children born after the implementation of this the novel EPI strategy were HBV carriers.

Effects of acupuncture on the immunological functions in hepatitis B virus carriers.

A contrast study on the effects of manual acupuncture and electroacupuncture was conducted in 60 cases of chronic hepatitis B carriers. The results demonstrated that the immunological functions, both cellular and humoral, were markedly regulated as evidenced by the negative turnover rates of HBsAg, HBeAg, anti-HBc and HBcAg, as well as the positive turnover rate of anti-HBe.

Passive transfer, rate of decay, and protein specificity of antibodies against equine arteritis virus in horses from a Standardbred herd with high seroprevalence.

OBJECTIVE: To determine rate of decay of passively acquired antibodies in Standardbred foals on a farm with a high seroprevalence to equine arteritis virus (EAV) and to determine whether vertical or horizontal transmission of the virus was responsible for infection on the farm. DESIGN: Repeated-measures study. ANIMALS: 46 Standardbred horses (15 brood mares and their foals, 5 stallions, and 11 young horses). PROCEDURE: Serum samples obtained from horses on the farm were evaluated by serum neutralization and western immunoblot analysis to detect EAV-specific antibodies. The half-life of passively acquired antibodies in foals was estimated by use of regression analysis. RESULTS: Most (14/15) of the mares evaluated were seropositive to EAV. After suckling, their foals were also seropositive. Mean biological half-life for passively acquired antibodies in serum samples obtained from foals was 32 days (r2 = 0.61). The foal born to a seronegative dam and all 11 young horses from the farm were seronegative to EAV. At least 2 of 5 stallions on the farm were persistently infected carriers that were shedding virus in their semen. Immunoblot analysis of seropositive serum samples most consistently recognized the M protein of EAV. CLINICAL IMPLICATIONS: Analysis of these data indicated that a modified-live EAV vaccine can be administered to foals after they are 8 months old without risk of interference from maternal antibodies, regardless of serologic status of the foal's dam. Horizontal transmission of EAV via the respiratory tract apparently was uncommon on the farm, indicating that mares primarily were infected by venereal transmission of virus from carrier stallions.

[A report on 8 seronegative converted HIV/AIDS patients with traditional Chinese medicine].

OBJECTIVE: For the first time, serum anti-HIV antibody negative conversion was being reported. METHODS: Eight confirmed HIV/AIDS patients (AC1, ARC 6, AIDS 1) were treated with TCM recipes (802, 806, 809, 810, Shengmaiyin, ZY-1), recheck the serum antibody and immunological function and intranuclear HIV-DNA was investigated with PCR amplifying assay and were long-term followed-up. RESULTS: After medication for 87-463 days, seronegative conversion occurred, PCR assay revealed that 5 cases were PCR(+), 2 of them(-), 1 turned seropositive again in the early stage. Observed continuously for 11-49 months, the "serum negative and intranuclear positive" state maintained. These patients belonged to immunosilent HIV-infection. The immunological function of all seronegative converted patients were good. CONCLUSIONS: AIDS is a reversible disease. Using medicinal herbs to enhance the immune function will facilitate the appearance of seronegative conversion, which has not been reported before. If it could be further confirmed, its mechanism elucidated, this may greatly strengthen the confidence of the patients.

Effect of streptomycin treatment on the shedding of and the serologic responses to Leptospira interrogans serovar hardjo subtype hardjobovis in experimentally infected cows.

Shedding patterns of and serologic responses to Leptospira interrogans serovar hardjo subtype hardjobovis (L. hardjobovis) have been studied in experimentally infected cows treated with streptomycin in comparison to experimentally infected cows receiving no such treatment. Fourteen cows were experimentally infected with L. hardjobovis, and blood and urine samples were collected weekly for 24 weeks. The microscopic agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) were used to determine serologic responses. The polymerase chain reaction (PCR) was used to determine bacterial shedding in urine. Six weeks after infection six cows were treated with the antibiotic streptomycin (25 mg/kg body weight/day); three cows were treated only once, and the remaining three were treated for five consecutive days. After treatment all six cows had lower serologic responses compared to the untreated cows. The treated cows became also PCR-negative two days after the first treatment, whereas the eight untreated cows remained PCR-positive for at least 70 days. Cows that stopped shedding did not resume shedding within the observation period. Since streptomycin treatment reduces the period of shedding, transmission of leptospira via contaminated urine might be prevented by a single treatment of an infected herd.

Demonstration of mother-to-infant transmission of hepatitis B virus by means of polymerase chain reaction.

To investigate the failure of vaccines to prevent mother-to-infant transmission of hepatitis B virus (HBV), serum, cord blood, and colostrum samples from eleven mothers, known to be carriers of hepatitis B surface antigen, and their infants were examined by means of a highly sensitive polymerase chain reaction (PCR) method. HBV-specific DNA was detected in ten maternal serum samples, eight samples of colostral whey, eight samples of colostral cells, and one cord blood sample. Four infants of mothers with HBV-DNA-positive colostrum showed low responsiveness to hepatitis B vaccine. The infant whose cord blood was positive for HBV DNA showed low responsiveness to hepatitis B vaccine and subsequently became an HBV carrier. These results suggest the need for further study to evaluate whether breastfeeding is advisable for HBV carriers.

Effect of Phyllanthus amarus on chronic carriers of hepatitis B virus.

In a preliminary study, carriers of hepatitis B virus were treated with a preparation of the plant Phyllanthus amarus for 30 days. 22 of 37 (59%) treated patients had lost hepatitis B surface antigen when tested 15-20 days after the end of the treatment compared with only 1 of 23 (4%) placebo-treated controls. Some subjects have been followed for up to 9 months. In no case has the surface antigen returned. Clinical observation revealed few or no toxic effects. The encouraging results of this preliminary study recommend continued evaluation of this plant and the active principles isolated from it.

Aflatoxin exposure, hepatitis B virus infection and liver cancer in Swaziland.

A study was carried out in Swaziland to assess the relationship between aflatoxin exposure, hepatitis B infection, and the incidence of liver-cell carcinoma, which is the most commonly occurring malignancy among males in Swaziland. Levels of aflatoxin intake were evaluated in dietary samples from households across the country, and crop samples taken from representative farms. Prevalence of hepatitis B markers was estimated from the serum of blood donors, and liver cancer incidence was recorded for the years 1979-83 through a national system of cancer registration. Across 4 broad geographic regions, there was a more than 5-fold variation in the estimated daily intake of aflatoxin, ranging from 3.1 to 17.5 micrograms. The proportion of HBV-exposed individuals was very high (86% in men), but varied relatively little by geographic region; the prevalence of carriers of the surface antigen was 23% in men, and varied from 21 to 28%. Liver cancer incidence varied over a 5-fold range, and was strongly associated with estimated levels of aflatoxin. In an analysis involving 10 smaller subregions, aflatoxin exposure emerged as a more important determinant of the variation in liver cancer incidence than the prevalence of hepatitis infection. Aflatoxin estimates from crop samples appeared to be a reasonable surrogate for dietary measurements. A comparison with dietary aflatoxin levels measured in an earlier survey in Swaziland suggested that programmes aimed at reducing contamination levels had had some success.

Latent carriers of brucellosis.

Of 272 heifers subjected to a brucellosis anamnestic test following one injection of K45/20A vaccine, 53 (19%) gave a positive result to the anti-bovine globulin test and 21 (8%) gave a complement fixation test titre at 1/16 or more. Three heifers (1%) gave a positive serum agglutination test (SAT) titre (60 iu or more) 12 weeks after the second injection of K45/20A vaccine. One of the three aborted at seven months' gestation (Brucella abortus culture positive), another had an SAT level of 100 iu 10 days after calving while the SAT titre of the third heifer continued to fall and remain negative after a normal calving. All the remaining heifers continued to give negative SAT. Recommendations are made for interpreting the anamnestic test for the diagnosis of the latent carrier state.