Risk of Injection-Site Abscess among Infants Receiving a Preservative-Free,Two-Dose Vial Formulation of Pneumococcal Conjugate Vaccine in Kenya

There is a theoretical risk of adverse events following immunization with a preservative-free, 2-dose vial formulation of 10-valent-pneumococcal conjugate vaccine (PCV10). We set out to measure this risk. Four population-based surveillance sites in Kenya (total annual birth cohort of 11,500 infants) were used to conduct a 2-year post-introduction vaccine safety study of PCV10. Injection-site abscesses occurring within 7 days following vaccine administration were clinically diagnosed in all study sites (passive facility-based surveillance) and, also, detected by caregiver-reported symptoms of swelling plus discharge in two sites (active household-based surveillance). Abscess risk was expressed as the number of abscesses per 100,000 injections and was compared for the second vs first vial dose of PCV10 and for PCV10 vs pentavalent vaccine (comparator). A total of 58,288 PCV10 injections were recorded, including 24,054 and 19,702 identified as first and second vial doses, respectively (14,532 unknown vial dose). The risk ratio for abscess following injection with the second (41 per 100,000) vs first (33 per 100,000) vial dose of PCV10 was 1.22 (95% confidence interval [CI] 0.37–4.06). The comparator vaccine was changed from a 2-dose to 10-dose presentation midway through the study. The matched odds ratios for abscess following PCV10 were 1.00 (95% CI 0.12–8.56) and 0.27 (95% CI 0.14–0.54) when compared to the 2-dose and 10-dose pentavalent vaccine presentations, respectively. In Kenya immunization with PCV10 was not associated with an increased risk of injection site abscess, providing confidence that the vaccine may be safely used in Africa. The relatively higher risk of abscess following the 10-dose presentation of pentavalent vaccine merits further study.     

Inactivation of Mycobacterium bovis in meat products.

The time-temperature combinations necessary to destroy Mycobacterium bovis in meat products were determined. In any given time, M. bovis was destroyed at temperatures 6 to 7 degrees C (ca. 12 degrees F) lower than those necessary for destruction of members of the Mycobacterium avium-Mycobacterium intracellulare complex. Hence, any processing heat adequate to kill M. avium-M. intracellulare-complex organisms will provide a very large safety factor with respect to M. bovis. Benzalkonium chloride treatment of wiener specimens for cultural examination effectively destroyed the normal flora of wiener emulsion without reducing the numbers of M. bovis. Treatment with a phenolic disinfectant followed by formaldehyde vapor was effective in disinfecting equipment contaminated with meat emulsion containing M. bovis.     

铜绿假单胞菌家兔肺部感染模型的建立与评价

目的:建立铜绿假单胞菌(PA,又名绿脓杆菌)肺部感染动物模型,并从病理学及细菌学、影像学等方面进行评价,研究铜绿假单胞菌对肺组织的致病作用。方法:24只健康清洁级新西兰大白兔随机分成2组,实验组采用经皮气管穿刺法,隔日注入铜绿假单胞菌反复感染家兔,对照组施以生理盐水。接种后隔日一次行胸部CT扫描。比较二组家兔的体温、血象及肺组织匀浆菌落计数;观察病理组织改变及胸部CT影像学变化。结果:注菌组家兔白细胞总数显著升高,肺组织匀浆菌落计数显著高于对照组。CT表现为双侧多发斑片状模糊影,部分可见实变及脓肿灶。大体标本可见家兔肺部结节、脓肿及出血灶,病理学镜下观察发现注菌组家兔肺组织内多个脓肿灶形成,大量中性粒细胞浸润,肺泡腔内大量渗出,部分出血,肺泡壁充血及肺水肿。随着注菌次数增多及时间推移,逐渐出现如肺泡间隔增厚、肉芽肿形成、实变等慢性肺部炎症的病理表现。结论:使用经皮气道穿刺法接种铜绿假单胞菌至新西兰兔肺部,可成功建立兔铜绿假单胞菌肺部感染模型。     

On the methods of disinfecting bronchofibroscopes

An apparatus is proposed for the wet disinfection of bronchofibroscopes which enables to wash with disinfectant solution the external surfaces of the tube and instrument channel while keeping dry the control mechanism. Several disinfecting regimens have been tested using chlorohexidine (Gibitan), benzalkonium chloride (Roccal), diocide and ethanol solutions. On experimental contamination of bronchofibroscopes with a P. aeruginosa culture effective disinfection was achieved using 0.5% aqueous and ethanol solution of chlorohexidine and 1% benzalkonium chloride solution (5-min, exposure in the circulation mode of the apparatus), 0.1% solution of diocide only produced a bactericidal effect after a 30-min, exposure. Adequate disinfection was not feasible when the endoscope was soaked in disinfectant. Similar results were obtained when bronchofibroscopes were disinfected in a clinical setup where they became contaminated with the most common pathogenic and potentially pathogenic microflora from the airways of patients suffering from purulent pulmonary diseases.     

儿童激素耐药型肾病综合征合并星形诺卡菌脑脓肿1例

本文报道1例激素耐药型肾病综合征儿童合并星形诺卡菌(Nocardia asteroides,N.asteroides)脑脓肿。患儿,男性,8岁,临床诊断为原发性肾病综合征(激素耐药型),病理诊断为局灶节段性肾小球硬化症(经典型)。肾穿后第4天患儿出现持续高热、抽搐,时有头痛,抗感染、抗凝治疗效果不佳。复查颅脑磁共振成像(magnetic resonance imaging,MRI)提示多发脑脓肿。头颅脓肿液经穿刺后培养显示为星形诺卡菌感染。予以多种抗生素联合糖皮质激素等治疗2个月,患儿体温正常,头痛缓解,脑脓肿范围明显缩小。因此,肾病综合征患儿在应用激素及免疫抑制剂治疗过程中如出现化脓性炎症,常规抗生素疗效差,应积极寻找病原,高度警惕诺卡菌病及其他机会性感染的可能。     

National outbreak of Salmonella serotype saintpaul infections: importance of Texas restaurant investigations in implicating jalapeño peppers

Background

In May 2008, PulseNet detected a multistate outbreak of Salmonella enterica serotype Saintpaul infections. Initial investigations identified an epidemiologic association between illness and consumption of raw tomatoes, yet cases continued. In mid-June, we investigated two clusters of outbreak strain infections in Texas among patrons of Restaurant A and two establishments of Restaurant Chain B to determine the outbreak''s source.

Methodology/Principal Findings

We conducted independent case-control studies of Restaurant A and B patrons. Patients were matched to well controls by meal date. We conducted restaurant environmental investigations and traced the origin of implicated products. Forty-seven case-patients and 40 controls were enrolled in the Restaurant A study. Thirty case-patients and 31 controls were enrolled in the Restaurant Chain B study. In both studies, illness was independently associated with only one menu item, fresh salsa (Restaurant A: matched odds ratio [mOR], 37; 95% confidence interval [CI], 7.2–386; Restaurant B: mOR, 13; 95% CI 1.3–infinity). The only ingredient in common between the two salsas was raw jalapeño peppers. Cultures of jalapeño peppers collected from an importer that supplied Restaurant Chain B and serrano peppers and irrigation water from a Mexican farm that supplied that importer with jalapeño and serrano peppers grew the outbreak strain.

Conclusions/Significance

Jalapeño peppers, contaminated before arrival at the restaurants and served in uncooked fresh salsas, were the source of these infections. Our investigations, critical in understanding the broader multistate outbreak, exemplify an effective approach to investigating large foodborne outbreaks. Additional measures are needed to reduce produce contamination.     

耐甲氧西林金黄色葡萄球菌皮肤脓肿小鼠感染模型的建立与评估

目的建立耐甲氧西林金黄葡萄球菌（methicillin-resistant Staphylococcus aureus,MRSA）小鼠皮肤脓肿感染模型,观察脓肿形成动态变化及药物对脓肿愈合的影响。方法 45只SPF级裸鼠随机分为PBS对照组、感染组及给药组,用临床分离鉴定的ST-239型MRSA菌株皮下注射感染裸鼠,对脓肿的形成过程进行时相性观察,测定脓肿体积的变化,并通过H.E染色观察皮肤的组织病理学改变。结果 PBS处理组小鼠皮肤无脓肿形成,显微镜下皮肤各层结构清楚;感染组和给药组可见到典型的脓肿,临床症状的时相性过程明显,感染组小鼠皮肤真皮层的胶原纤维消失,可见大量炎性细胞浸润,给药组小鼠的脓肿体积在整个实验周期内低于感染组,且在第5天时与感染组相比有差异。结论成功建立MRSA小鼠皮肤脓肿感染模型,该模型的建立可为进一步研究来源于临床MRSA菌株的病原特性、发病机制、治疗方法等提供可靠的动物模型。     

Primary Isolation Of Mycobacterium chelonei Subspecies abscessus from Pus Inoculated into Peptone Broth

We have described the isolation of Mycobacterium chelonei subspecies abscessus which on two occasions grew out within 4 days in routine cultures after inoculation with purulent material from injection abscesses in a patient with diabetes mellitus. Media isolation and culture characteristics of this organism in comparison to others in the Mycobacterium fortuitum complex are described. Mycobacteria in routine laboratory media can be mistaken for diphtheroids or other "contaminants" or can be overlooked entirely. The possibility of clinical infection of mycobacterial species should be kept in mind when confronted with "sterile" abscesses at injection sites.     

Comparative testing of disinfectants using proposed European surface test methods

A surface test method for disinfectants currently under development as a standard European test method is described. The test involves determining the number of viable organisms recoverable from a contaminated stainless steel surface before and after application of disinfectant. Evaluation of a range of disinfectant agents and products currently used in the UK indicated that products at recommended use concentrations produced log reductions in viable count ranging from < 1.0 to > 6.4 (i.e. no detectable survivors) after a 5 min contact period against Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecium and Candida albicans. Increased activity was observed by increasing the disinfectant contact time to 30 min. Addition of 3% w/v albumin to the test suspension used to inoculate surfaces caused a substantial reduction in activity.     

Resistance of Pseudomonas to Quaternary Ammonium Compounds: II. Cross-Resistance Characteristics of a Mutant of Pseudomonas aeruginosa

Tube dilution experiments showed that benzalkonium chloride (BC)-resistant mutants of Pseudomonas aeruginosa grown in the presence of 1,000 mug of BC per ml were at least 20 times more sensitive to polymyxin B and colistin sulfate than the BC-sensitive (BCS) parent strain. BCS cells selected for resistance to 500 mug of polymyxin B per ml remained sensitive to BC. There was little difference in the amount of carbenicillin, gentamicin sulfate, or rifampin needed to prevent growth of either the BCS or BC-resistant (BCR) strains. Growth of BCR cells was inhibited by ethylenediaminetetraacetate at a concentration of 400 mug/ml or less, whereas the BCS strain grew at ethylenediaminetetraacetate levels of 10,000 mug/ml. Phenylmercuric acetate and thimerosal inhibited growth of BCR and BCS cells at concentrations of 10 mug/ml or less. BCR cells were cross-resistant to >1,000 mug/ml concentrations of five other quaternary ammonium compounds, including three with C(16) alkyls and two with alkyl groups of shorter length. The BCS strain was also resistant to >1,000 mug/ml concentrations of the three quaternary ammonium compounds with C(16) alkyl groups but, in addition to BC, was inhibited by 200 mug/ml levels or less of the two quaternary ammonium compounds containing alkyl groups of less than 16 carbon atoms.     

Investigations into the survival of Pseudomonas aeruginosa in poloxamer-iodine

Laboratory investigations were conducted to study potential mechanisms for prolonged survival of Pseudomonas aeruginosa in poloxamer-iodine (PxI). P. aeruginosa organisms isolated from PxI and adapted for growth in distilled water or found as part of a mixed microbial population from water in a manufacturing plant did not survive more than 15 s after challenge in stock PxI solution. Batches of PxI were compounded in the laboratory to determine the survival and growth of P. aeruginosa during the various stages of preparation. No P. aeruginosa organisms were recovered from the finished product at 1 min after the addition of iodine-iodide. However, we found P. aeruginosa in PxI 48 h after adding sterile PxI to the inside of a naturally contaminated polyvinyl chloride water distribution pipe. These organisms (10(4) CFU/ml) survived for as long as 98 days in contaminated stock PxI after it was removed from the polyvinyl chloride pipe. Both decreasing the free iodine level through addition of potassium iodide and increasing the free iodine level through dilution of the product resulted in an increased length of survival of P. aeruginosa in contaminated PxI solution. Comparative survival studies with pipes of different composition revealed that other materials may exert an effect similar to polyvinyl chloride. We concluded that polyvinyl chloride and perhaps other materials may play an important role in the survival of P. aeruginosa in iodophors and may be one source of resistant microbial populations when used in manufacturing plants which produce these antimicrobial solutions.     

Comparison of the pathogenicity of three species of coagulase-negative Staphylococcus in a mouse model with and without a foreign body

Staphylococcus schleiferi, Staphylococcus lugdunensis, and Staphylococcus epidermidis produce a high incidence of abscesses in a mouse model with an implanted foreign body. We investigated the significance of the foreign body in this process. Fourteen strains of S. schleiferi, S. epidermidis, and S. lugdunensis were tested in our model. A preadhered foreign body was implanted into one mouse group, followed by injection of a test strain. Another group received injection without implant. Abscesses were assessed at 7 days; foreign bodies and infected tissues were cultured. The percent of samples that developed abscesses or were culture positive was compared for each strain. Nearly all mice infected with S. schleiferi developed abscesses and were culture positive. The foreign body made no difference in abscess formation for three of four S. schleiferi but increased the incidence of both organism recovery and abscess for three of five S. epidermidis. The foreign body enhanced abscess formation for four of five S. lugdunensis, with all five strains yielding significantly more culture recovery. Although the pathogenicity of nine strains was increased by the foreign body, five strains yielded high abscess and culture recovery rates that were not enhanced by its presence.     

Investigations into the survival of Pseudomonas aeruginosa in poloxamer-iodine.

Laboratory investigations were conducted to study potential mechanisms for prolonged survival of Pseudomonas aeruginosa in poloxamer-iodine (PxI). P. aeruginosa organisms isolated from PxI and adapted for growth in distilled water or found as part of a mixed microbial population from water in a manufacturing plant did not survive more than 15 s after challenge in stock PxI solution. Batches of PxI were compounded in the laboratory to determine the survival and growth of P. aeruginosa during the various stages of preparation. No P. aeruginosa organisms were recovered from the finished product at 1 min after the addition of iodine-iodide. However, we found P. aeruginosa in PxI 48 h after adding sterile PxI to the inside of a naturally contaminated polyvinyl chloride water distribution pipe. These organisms (10(4) CFU/ml) survived for as long as 98 days in contaminated stock PxI after it was removed from the polyvinyl chloride pipe. Both decreasing the free iodine level through addition of potassium iodide and increasing the free iodine level through dilution of the product resulted in an increased length of survival of P. aeruginosa in contaminated PxI solution. Comparative survival studies with pipes of different composition revealed that other materials may exert an effect similar to polyvinyl chloride. We concluded that polyvinyl chloride and perhaps other materials may play an important role in the survival of P. aeruginosa in iodophors and may be one source of resistant microbial populations when used in manufacturing plants which produce these antimicrobial solutions.     

Mechanism of resistance to benzalkonium chloride by Pseudomonas aeruginosa.

The mechanisms of resistance of Pseudomonas aeruginosa to benzalkonium chloride (BC) were studied. The effluence of cell components was observed in susceptible P. aeruginosa by electron microscopy, but resistant P. aeruginosa seemed to be undamaged. No marked changes in cell surface potential between Escherichia coli NIHJC-2 and a spheroplast strain were found. The contents of phospholipids (PL) and fatty and neutral lipids (FNL) in the cell walls of resistant P. aeruginosa were higher than those in the cell walls of susceptible P. aeruginosa. The amounts of BC adsorbed to PL and FNL of cell walls of BC-resistant P. aeruginosa were lower than those for BC-susceptible P. aeruginosa. Fifteen species of cellular fatty acids were identified by capillary gas chromatography and gas chromatography-mass spectrometry. The ability of BC to permeate the cell wall was reduced because of the increase in cellular fatty acids. These results suggested that the resistance of P. aeruginosa to BC is mainly a result of increased in the contents of PL and FNL. In resistant P. aeruginosa, the decrease in the amount of BC adsorbed is likely to be the result of increases in the contents of PL and FNL.     

Mechanism of resistance to benzalkonium chloride by Pseudomonas aeruginosa

The mechanisms of resistance of Pseudomonas aeruginosa to benzalkonium chloride (BC) were studied. The effluence of cell components was observed in susceptible P. aeruginosa by electron microscopy, but resistant P. aeruginosa seemed to be undamaged. No marked changes in cell surface potential between Escherichia coli NIHJC-2 and a spheroplast strain were found. The contents of phospholipids (PL) and fatty and neutral lipids (FNL) in the cell walls of resistant P. aeruginosa were higher than those in the cell walls of susceptible P. aeruginosa. The amounts of BC adsorbed to PL and FNL of cell walls of BC-resistant P. aeruginosa were lower than those for BC-susceptible P. aeruginosa. Fifteen species of cellular fatty acids were identified by capillary gas chromatography and gas chromatography-mass spectrometry. The ability of BC to permeate the cell wall was reduced because of the increase in cellular fatty acids. These results suggested that the resistance of P. aeruginosa to BC is mainly a result of increased in the contents of PL and FNL. In resistant P. aeruginosa, the decrease in the amount of BC adsorbed is likely to be the result of increases in the contents of PL and FNL.     

Effect of ciprofloxacin on subcutaneous abscesses induced with Staphylococcus epidermidis and a foreign body implant in the mouse

Subcutaneous abscesses were induced in mice with Staphylococcus epidermidis strain G19-85 and a foreign body implant. The MIC of ciprofloxacin for this strain was 0.25 microgram/ml. The ciprofloxacin dosage, 120 mg/kg/day, was divided into three injections, administered to the mice subcutaneously at 8 h intervals. Serum concentration kinetics in normal mice (n = 50) were determined. The peak serum level of ciprofloxacin was 3.18 micrograms/ml at the 15 min sampling time; the trough level was 0.53 micrograms/ml at 8 h. Abscesses were found in 96% (n = 49) of the untreated, infected control mice. Three modes of treatment with ciprofloxacin were tested: (1) four prophylactic injections of ciprofloxacin prior to infection reduced abscess formation to 64% (p less than or equal to 0.0002, n = 50). (2) Eleven therapeutic injections, initiated 4 days after infection, reduced abscess formation to 86% (p less than or equal to 0.17, n = 49). (3) One prophylactic injection prior to surgery and five therapeutic injections after infection reduced abscess formation to 43% (p less than or equal to 0.0001, n = 49). Culture results correlated with the abscess formation rates.     

Adaptive resistance to benzalkonium chloride,amikacin and tobramycin: the effect on susceptibility to other antimicrobials

AIMS: To produce strains of antimicrobial-resistant Pseudomonas aeruginosa via adaptation to benzalkonium chloride, amikacin and tobramycin and to then examine the incidence, or otherwise, of cross-resistance between antibiotics and between antibiotics and benzalkonium chloride. METHODS AND RESULTS: Adaptation was obtained by progressive subculturing in subinhibitory concentrations of the antimicrobials. Pseudomonas aeruginosa NCIMB 10421 adapted to grow in high concentrations of benzalkonium chloride (BC) had lower MIC to antibiotics than the wild type, whereas Ps. aeruginosa adapted to grow in antibiotics had greater MIC to benzalkonium by a small degree. CONCLUSIONS: Adaptive resistance to BC of Ps. aeruginosa generally produced cultures with a decrease in resistance to several antibiotics. Adaptive resistance to the aminoglycosides Ak and Tm produced a low-level increase in tolerance to BC. The adaptive mechanisms of resistance appear to be different for the different types of antimicrobials used. SIGNIFICANCE AND IMPACT OF THE STUDY: The relationships between biocide and antibiotic resistance are complex. It appears, from this study, that an organism resistant to a common biocide can become sensitive to antibiotics, but the converse was not true. Could this observation be used in a strategy to alleviate antibiotic resistance?     

甲硝哒唑与庆大霉素联合治疗厌氧菌与兼性菌混合感染的动物实验研究

厌氧菌与兼性菌的混合感染及其治疗是目前临床上感染性疾病和抗生素治疗研究领域内的重要问题之一,本文对小鼠混合感染的动物模型甲硝哒唑与庆大霉素治疗结果显示:当脆弱类杆菌10~9CFU/ml大肠杆菌10~8CFU/ml混合感染小鼠6h后,单用甲硝哒唑治疗死亡率为9/10,脓肿率为1/10;单用庆大霉素组死亡率2/10,脓肿率为10/10;两药联用死亡率为2/10,无脓肿发生。两药联用的治疗比较:即时组基本同6h组,而12h开始治疗组死亡率达6/10。脓肿率4/6。提示应及早联合用药以阻断细菌的协同致病作用,控制感染。     

Abcès rénal et périrénal chez l'enfant.

One child with a pure perinephric abscess and three with renal abscesses, one of which had perinephric extension, are described. All presented with a long course of subacute infection leading to localizing symptoms or signs in the flank. The diagnosis was confirmed by radiologic examination. All the abscesses were surgically drained at various intervals after diagnosis, while the patients were receiving antibiotic therapy. Salvage of renal function was possible in all cases. A rational approach to the diagnosis and management of such abscesses is emphasized.     

Resistance of Pseudomonas to Quaternary Ammonium Compounds. I. Growth in Benzalkonium Chloride Solution

Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of growth leveled off or was completely depressed. Minimal salts solutions of pure benzalkonium chloride (PBC) containing no ammonium acetate did not support bacterial growth. When ammonium acetate was added to PBC solutions in the same concentrations found in CBC solutions, growth patterns developed that were comparable to those found with CBC. Likewise, (NH(4))(2)SO(4) added to PBC solutions supported growth of both organisms. P. aeruginosa was initially resistant to CBC levels of 0.02% and it was adapted to tolerate levels as high as 0.36%. Strain Z-R was naturally resistant to 0.4% CBC. Since ammonium acetate, carried over by the CBC used in drug formulations and disinfectant solutions, has the potential to support the growth of resistant bacteria and thus make possible the risk of serious infection, it is suggested that regulations allowing the presence of ammonium acetate in CBC solution be reconsidered.