Dissertation (D.P.H.)--University of Michigan.

Thesis (MMed)--Stellenbosch University, 2012. / Includes bibliography / ENGLISH ABSTRACT: Introduction Acute respiratory tract infections cause significant morbidity and mortality worldwide, and are the main reason for the utilisation of health care services. Identifying the aetiological cause of lower respiratory tract infections (LRTIs) is difficult at the best of times, and more than 20 viruses and bacteria have been associated with LRTIs, which cannot be distinguished with clinical examination alone. Viruses can be detected in respiratory samples by a variety of methods, and without exception molecular methods have proven to be more sensitive than non-molecular-based tests. The increased sensitivity of molecular methods may assist in expanding our knowledge of the pathogenesis of severe respiratory tract infections, and could have a positive influence on patient management, infection control, vaccination strategies and public health. Aims and objectives 1. Determine the viral causes of lower respiratory tract infections requiring admission in using shell vial culture with immunofluorescent staining and two multiplex PCR assays, the Seeplex® RV15 ACE Detection system (Seeplex® RV15 ACE) and the Respiratory Multiplex Real-Time RT-PCR LightMix® Customised Kit (Resp Multiplex RT-PCR). 2. Compare the Seeplex® RV15 ACE and the Resp Multiplex RT-PCR with shell vial culture for the detection of respiratory viruses in routine diagnostic respiratory samples. 3. Examine the demographic and clinical characteristics associated with each respiratory viral pathogen. Materials and Methods One hundred and thirty-eight paediatric patients, admitted to Tygerberg Children’s Hospital from May 2010 to August 2010 with a presumptive diagnosis of an acute respiratory tract infection were included in the study. Nasopharyngeal or tracheal aspirates were collected, and all samples were tested by all three diagnostic methods. Clinical, demographic and laboratory data were collected through a systematic review of medical and laboratory records and subsequently anonymised Results Thirty-seven viruses were detected in 36 samples (26.1%) by shell vial culture with immunofluorescent staining; 169 viruses in 102 samples (73.9%) with the Seeplex® RV15 ACE; and 90 viruses in 73 samples (52.9%) with the Resp Multiplex RT-PCR. Shell vial culture had excellent specificity, but low sensitivity for all of the respiratory viruses. Conversely, the Seeplex® RV15 ACE had excellent sensitivity for all viruses, but slightly lower specificity. This was due to the detection of additional viruses, which may have been true positives due to the increased sensitivity of this assay. The Resp Multiplex RTPCR had excellent sensitivity and specificity. At least one respiratory pathogen could be identified in 80% of the patients. At least one virus was detected in 57% of patients, bacterial micro-organisms in 6%, and both viral and bacterial pathogens in 17%. Viral-bacterial co-infections were associated with increased severity compared to other infections, as these children were more likely to receive steroids and a blood transfusion (p = 0.002), and more likely to require mechanical ventilation (p < 0.001) and admission to the intensive care unit (p = 0.04). Conclusions We confirmed that molecular techniques are significantly more sensitive than shell vial culture for the detection of respiratory viruses in children. Due to their highly specific nature and the genetic variability observed in viruses, an excellent, continuous quality control programme is essential to ensure the continued superiority of these assays. Viral-bacterial co-infection is associated with increased severity of LRTIs in children. Further research is needed to elucidate the precise pathogenic and immunologic mechanism of this interaction. / AFRIKAANSE OPSOMMING: Inleiding Akute lugweg infeksies is verantwoordelik vir beduidende morbiditeit en mortaliteit wêreldwyd en is die hoofrede vir die benutting van gesondheidsdienste. Identifisering van die oorsaak van laer lugweg infeksies is baie moeilik en meer as 20 virusse en bakterieë word hiermee geassosieer. Ongelukkig kan kliniese ondersoek alleen nie onderskei tussen die verskillende organismes nie. Respiratoriese virusse kan deur ‘n wye verskeidenheid van toets metodes aangetoon word. Molekulêre metodes is sonder uitsondering meer sensitief as nie-molekulêre metodes. Hul verhoogde sensitiwiteit mag help om ons kennis oor die patogenese van erge lugweg infeksies te verbreed en kan ’n positiewe invloed op pasiëntbehandeling, infeksiebeheer, immunisasie strategieë en publieke gesondheidsorg hê. Doel van die Ondersoek 1. Bevestig die virale oorsake van laer lugweg infeksies deur gebruik te maak van “shell vial” kultuur met immunofluoressensie en twee veelvoudige molekulêre toetse, die Seeplex® RV15 ACE en die Resp Multiplex RT-PCR. 2. Vergelyk die Seeplex® RV15 ACE en die Resp Multiplex RT-PCR met “shell vial” kultuur vir die aantoning van respiratoriese virusse in roetine diagnostiese monsters. 3. Ondersoek die demografiese en kliniese eienskappe wat met elke respiratoriese patogeen geassosieer word. Metodiek en Materiaal Een honderd agt-en-dertig kinders wat toegelaat is tot Tygerberg Kinderhopitaal vanaf Mei 2010 tot Augustus 2010 met ’n voorlopige diagnose van ’n akute lugweg infeksie is in die studie ingesluit. Nasofaringeale of trageale aspirate is van elke pasiënt gekollekteer en met al drie diagnostiese metodes ondersoek. Kliniese, demografiese en laboratorium data is gekollekteer deur ’n sistematiese ondersoek van mediese en laboratorium rekords en daarna anoniem gemaak. Resultate Sewe-en-dertig virusse is in 36 monsters (26.1%) aangetoon deur “shell vial” kultuur met immunofluoressensie; 169 virusse in 102 monsters (73.9%) deur die Seeplex® RV15 ACE; en 90 virusse in 73 monsters (52.9%) deur die Resp Multiplex RT-PCR. “Shell vial” kultuur het uitstekende spesifisiteit gehad, maar sensitiwiteit was laag vir al die virusse. Teenoorgesteld hiermee het die Seeplex® RV15 ACE hoë sensitiwiteit vir al die viruses gehad, maar effe laer spesifisiteit. Dit was as gevolg van die aantoning van addisionele virusse, wat moontlik ware positiewe resultate kon wees as gevolg van die verhoogde sensitiwiteit van hierdie toets metode. Die Resp Multiplex RT-PCR het uitstekende sensitiwiteit en spesifisiteit gehad. Ten minste een respiratoriese patogeen is in 80% van die pasiënte geidentifiseer. Een of meer virusse was in 57% van die pasiënte aangetoon, bakterieë in 6% en beide virale en bateriële patogene in 17%. Virale-bakteriële ko-infeksies, in vergelyking met ander infeksies, was geassosieer met meer ernstige lugweg infeksies aangesien hierdie kinders meer geneig was om steroïede en ’n bloedtransfusie te ontvang (p = 0.002). Hulle het ook meer waarskynlik meganiese ventilasie (p < 0.001) en toegang tot die intensiewe sorg eenheid benodig (p = 0.04). Gevolgtrekkings Ons het bevesitg dat molekulêre tegnieke aansienlik meer sensitief is as “shell vial” kultuur vir die aantoning van respiratoriese virusse in kinders. As gevolg van hul hoogs spesifieke aard en die genetiese variasie waargeneem in virusse, is ’n uitstekende deurlopende kwaliteitsbeheer program noodsaaklik vir die voortgesette uitneemendheid van hierdie metodes. Virale-bakteriële ko-infeksies word geassosieer met meer ernstige laer lugweg infeksies in kinders. Verdere navorsing is nodig om die presiese patogenetiese en immunologiese meganisme van hierdie interaksie toe te lig.

[Truncated abstract] Background Emergency department (ED) presentations of respiratory infections are not well described. Baseline ED data are needed to monitor trends, and to help evaluate the impact of health interventions, and assess changes in clinical practice for these conditions. Aims: To describe the epidemiology of respiratory infections diagnosed in Western Australian hospital EDs from 2000 to 2003; to determine the extent and usefulness of bacterial cultures ordered in hospital, and to describe and evaluate the antibiotic prescribing pattern in the ED setting. Methods: The cohort consisted of patients diagnosed with a respiratory infection at the ED of Perth's major metropolitan teaching hospitals from 1 July 2000 to 30 June 2003. The analysis was based on a linked data set containing patient data from the Emergency Department Information System, the Hospital Morbidity Data Set, the death registry, and the Ultra Laboratory Information System. Further, a sample of patient medical records from 1 adult hospital was examined to assess antibiotic prescribing practice. Results: Overall, there were 37,455 presentations (28,885 patients) given an ED diagnosis of a respiratory infection. Of these, 14,884 (39.7%, 95% CI: 39.2 to 40.2) were admitted and 715 (1.9%, 95% CI: 1.8 to 2.0) died in hospital. The infections included; 48.1% acute upper respiratory infections (URI), 18.5% pneumonia, 23.5% other acute lower respiratory infections (LRI), 7.4% chronic obstructive pulmonary disease with lower respiratory infection (COPD+), 1.3% influenza or viral pneumonia and 1.2% other URI. Children accounted for 80.7% of acute URI diagnoses, COPD+ mainly affected the elderly, just over 40% of pneumonia diagnoses were in patients 65 years or older and 30.7% in patients younger than 15 years. ... The most common pathogen isolated from blood was Streptococcus pneumoniae and 10.4% (95% CI: 4.8 to 16.0) had reduced susceptibility to penicillin. For those diagnosed with pneumonia, Strep. pneumoniae accounted for over 90% of pathogens isolated from the blood of young children and isolation of Enterobacteriaceae from blood increased with age. Around 30% of patients had positive sputum cultures and from these Haemophilus influenzae, Strep. pneumoniae and Pseudomonas aeruginosa were the most common organisms grown. Of those diagnosed with pneumonia, acute LRI or COPD+, 34.7% (95% CI: 26.1 to 43.3) of S. aureus isolated from sputum and 16.4% (95% CI: 7.1 to 25.7) from blood were methicillin resistant. Of 366 adult patient medical records reviewed, 56.8% (95% CI: 51.7 to 61.9) noted that an antibiotic was prescribed in the ED and amoxycillin was the most frequently prescribed. For those with pneumonia, concordance between prescribing guidelines and practice was low. Conclusions The administrative data sets used in the present study are useful for monitoring outcomes for respiratory infections diagnosed in the ED. Pneumonia continues to place a burden on the hospital system. Routine blood and sputum cultures have limited value. However, an appropriately designed surveillance program is needed to monitor potential Abstract v respiratory pathogens and assist in monitoring the appropriateness of current empiric antimicrobial therapy.

Thesis (MCur)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Annually more than 3.5 million children worldwide, less than five years of age die of diarrhoea and acute lower respiratory-tract infections. Over the last two decades, the care of pre-school children outside of their homes has become more common in most parts of the world and has contributed to an increased risk of respiratory-tract and gastrointestinal infections in children. Children attending day-care centres are at an increased risk for diarrhoea and respiratory-tract infections and hands are the primary vehicle for transmission of infectious diseases. Thus, hand hygiene is essential for preventing and controlling of infection in the health care and community settings. Waterless hand sanitizer as an alternative to hand washing was investigated. Rinse-free hand sanitizer programmes in the community may be effective, safe and feasible. The aim of the study was to systematically appraise evidence on the effect of alcohol-based hand rub in the prevention of diarrhoea and acute respiratory-tract infection among children aged five years and below in community settings. The primary outcome of the study was to assess the incidence of respiratory-tract infection and diarrhea. Diarrhoea is defined by the World Health Organization as the excretion of three or more loose or liquid stools per day (or more frequent excretion than is normal for the individual). The secondary outcome was to assess mortality, admission to hospital and duration of hospital stay. A comprehensive search for relevant studies was conducted on the following databases from 1990 to 2014: EMBASE, MEDLINE, CINAHL, Google Scholar and Cochrane Central Register of Controlled Trials (CENTRAL). We searched the reference lists of all relevant articles and textbooks for more studies. Unpublished data previously presented at international and scientific meetings have been included in the review. Proceedings of international conferences on diarrhoea and respiratory-tract infection among children were searched for relevant articles. Subject experts were contacted. Two reviewers, Joelynn Steyn (JS) and Oswell Khondowe (OK) selected studies following a two-step study selection process. This review considered all published randomized controlled trials and quasi-experimental designs published from January 1990 to July 2014. The first step was the selection of studies based on titles and abstracts. Both reviewers selected eligible studies which met the set criteria. During the second step, both reviewers retrieved the full-text articles of the studies and assessed the methodological quality of the studies. Four studies were included in this review. The included studies met most of the quality assessment criteria as stipulated in the Cochrane risk assessment tool. Two studies were clusterrandomized controlled trials, one was a block randomized controlled trial and one was a randomized controlled trial. Disagreements were resolved by discussion and where a lack of consensus existed, consultation with a third reviewer occurred. The use of alcohol hand rub as compared to control interventions significantly reduced the incidence of diarrhoea in children (RR 0.79, 95% CI 0.63 to 0.99). Statistical heterogeneity was observed among the included studies (I²=69, p=0.04). However this review found no significant difference in respiratory-tract infections between intervention groups versus control as observed from the confidence interval (RR 0.98, 95% CI 0.90 to 1.07, p=0.63). The results should be interpreted with caution due to the limited number of studies conducted in communities with alcoholbased hand rub used by caregivers. Due to limited studies in this review, it makes it difficult to make strong conclusions on findings and to provide sufficient evidence to guide future research. We therefore recommend that more studies with high quality methodologies, using randomized controlled trial designs be conducted especially in poor resourced communities. / AFRIKAANSE OPSOMMING: Meer as 3.5 miljoen kinders jonger as vyf jaar oud sterf jaarliks wêreldwyd as gevolg van diarree en akute laer respiratoriese lugweginfeksies. Oor die laaste dekades het die versorging van voorskoolse kinders buite hul tuiste meer algemeen geword in die meeste dele van die wêreld wat bygedra het tot ’n risiko in die toename van respiratoriese en spysverteringskanaalinfeksies by kinders. Kinders by dagsorgsentrums het ’n groter risiko vir diarree en respiratoriese lugweë infeksies want die oordra van siekte-infeksies word veral deur die hande wat as die primêre bron daarvan beskou word, gesien. Dus is hand-higiëne noodsaaklik om infeksies in gesondheidsorg en gemeenskapsentrums te voorkom en te beheer. ’n Waterlose hande-ontsmettingsmiddel as ’n alternatief om hande te was, is ondersoek. Spoelvrye hande-ontsmettingsmiddel programme in die gemeenskap mag effektief, veilig en uitvoerbaar wees. Die doel van die studie was om sistematies die geslaagdheid van bewyse op die effek van alkoholgebaseerde hande-smeermiddel in die voorkoming van diarree en akute lugweginfeksies by kinders 5 jaar en jonger in gemeenskapsentrums te ondersoek. Die primêre uitkoms van die studie was om die voorkoms van respiratoriese lugweginfeksie en diarree te asseseer. Diarree soos gedefinieer deur die WGO is die uitskeiding van drie of meer los- of waterige stoelgange per dag (of meer gereelde uitskeiding wat normaal vir die individu is). Die sekondêre uitkoms was om mortaliteit, toelating tot die hospitaal en duur van hospitaalverblyf te assesseer. ’n Omvattende soektog vir relevante studies was op die volgende databasisse van 2004-2014 uitgevoer: EMBASE, MEDLINE, CINAHL, Google Scholar en Cochrane Sentrale Register van Beheerde Toetse. Ons het die verwysingslyste van alle relevante artikels en handboeke vir meer navorsingstudies nagegaan. Ongepubliseerde data wat voorheen aangebied is by internasionale en wetenskaplike vergaderings, is ingesluit in die oorsig. Bevindings by internasionale konferensies oor diarree en lugweginfeksies by kinders was nagegaan in die soektog na relevante artikels. Onderwerpdeskundiges was gekontak. Die twee navorsers, Joelynn Steyn (JS) en Oswell Khondowe (OK) het studies geselekteer deur ’n twee-stap studieselekteringsproses te volg. Die oorsig het alle gepubliseerde, ewekansige gekontroleerde proewe en kwasi-eksperimenteerde studies oorweeg tussen Januarie 1990 en Julie 2014. Die eerste stap was die selektering van studies gebaseer op hul titels en opsommings. Beide navorsers het geskikte studies slegs geselekteer as die studie aan die bepaalde kriteria voldoen het. Tydens die tweede stap het beide navorsers die volledige artikels geneem van die studies geselekteer en die gehalte van die metodologie geassesseer. Vierstudies is in die oorsig ingesluit. Die ingeslote studies het aan die meeste vereistes soos deur die Cochrane risiko assesseringsinstrument gestipuleer voldoen. Twee studies was groep-ewekansige gekontroleerde proewe, een was ’n blok ewekansige gekontroleerde proef en een was ’n ewekansige gekontroleerde proef. Verskille is opgelos deur bespreking en waar daar onderbreking in konsensus was, het ’n konsultasie met ’n derde beoordelaar plaasgevind. Die gebruik van ’n alkohol handreiniger, soos vergelyk met kontrole-intervensies, het die voorkoms van diarree in kinders beduidend verminder (RR 0.79, 95% CI 0.63 to 0.99). Statistiese heterogeniteit is egter tussen die ingeslote studies waargeneem (I²=69, p=0.04). Hierdie studie het geen beduidende verskille in lugweg infeksies tussen die intervensiegroepe teenoor die kontrolegroep gevind nie soos waargeneem uit die vertroue interval (RR0.98, 95% CI 0.90 to 1.07, p=0.63). Die resultate moet met omsigtigheid geïnterpreteer word as gevolg van die beperkte aantal studies wat in gemeenskappe uitgevoer was met alkohol-gebasseerde handreiniger wat deur versorgers gebruik word. As gevolg van die beperkende aantal studies in hierdie studie, is dit moeilik om sterk gevolgtrekkings te maak op bevindinge en om voldoende bewyse te gee om toekomstige navorsing te rig. Ons beveel dus aan dat meer studies met hoë kwaliteit metodologie en wat ewekansige gekontroleerde proef-ontwerpe gebruik, uitgevoer word, veral in swak-toegeruste gemeenskappe. (RR0.98, 95% CI 0.90 to 1.07, p=0.63). Die resultate moet met omsigtigheid geïnterpreteer word as gevolg van die beperkte aantal studies wat gedoen is in gemeenskappe met alkohol-

published_or_final_version / Community Medicine / Master / Master of Public Health

published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy

jdelvall@upc.edu.pe / Acute respiratory infections are responsible for high morbi–mortality in Peruvian children. However, the etiological agents are poorly identified. This study, conducted during the pandemic outbreak of H1N1 influenza in 2009, aims to determine the main etiological agents responsible for acute respiratory infections in children from Lima, Peru. Nasopharyngeal swabs collected from 717 children with acute respiratory infections between January 2009 and December 2010 were analyzed by multiplex RT-PCR for 13 respiratory viruses: influenza A, B, and C virus; parainfluenza virus (PIV) 1, 2, 3, and 4; and human respiratory syncytial virus (RSV) A and B, among others. Samples were also tested with direct fluorescent-antibodies (DFA) for six respiratory viruses. RT-PCR and DFA detected respiratory viruses in 240 (33.5%) and 85 (11.9%) cases, respectively. The most common etiological agents were RSV-A (15.3%), followed by influenza A (4.6%), PIV-1 (3.6%), and PIV-2 (1.8%). The viruses identified by DFA corresponded to RSV (5.9%) and influenza A (1.8%). Therefore, respiratory syncytial viruses (RSV) were found to be the most common etiology of acute respiratory infections. The authors suggest that active surveillance be conducted to identify the causative agents and improve clinical management, especially in the context of possible circulation of pandemic viruses

Streptococcus pneumoniae é o agente causador de diversas doenças, tais como meningite e pneumonia. PspC (Pneumococcal surface protein C) foi descrito como um importante candidato vacinal proteico de ampla cobertura e com baixo custo de produção. Trata-se de um fator de virulência, capaz de ligar-se ao Fator H (FH) e a IgA secretório (sIgA). Como PspC é um antígeno polimórfico, é crucial a avaliação da sua variabilidade. Foi determinado o grupo de PspC de treze linhagens de pneumococo isoladas no Hospital Universitário da Universidade de São Paulo. Soros contra diferentes grupos de PspC foram produzidos e PspC do grupo 3 (PspC3) foi capaz de induzir anticorpos que reconhecem diferentes grupos de PspC. Foi observada ainda uma pequena redução na ligação de FH e sIgA por anticorpos anti-PspC3 em ensaios in vitro. No entanto, não foi possível observar proteção contra um modelo de colonização da nasofaringe de camundongos através da imunização com PspC3, possivelmente por deficiências no modelo experimental. / Streptococcus pneumoniae is the causative agent of several diseases, such as meningitis and pneumonia. PspC (Pneumococcal surface protein C) has been described as an important vaccine candidate protein as it could provide wide coverage with low cost of production. PspC is a virulence factor capable of binding to Factor H (FH) and secretory IgA (sIgA). PspC is polymorphic antigen, and therefore it is crucial to evaluate its variability. In the present work we have determined the PspC group of 13 pneumococcal isolates obtained at the University Hospital of the University of São Paulo. Antisera against different PspC groups were produced and PspC group 3 (PspC3) was able to induce antibodies that recognized different groups of PspC. Antibodies to PspC3 reduced binding of FH and sIgA to pneumococcus in in vitro assays. However, no protection was observed against a murine model of nasopharyngeal colonization by immunization with PspC3. This was possibly due to deficiencies in the experimental model.

This thesis was based on a collection of my published works. Chapter 1 introduced the idea that infections, both acute and chronic, were risk factors for stroke. Various infections and micro-organisms associated with stroke were discussed. Specifically, the relationship between micro-organisms such as Cytomegalovirus, Helicobacter pylori, dental pathogens, and stroke were discussed. The theories of the pathogenesis of atherosclerosis were presented. Chapter 1 also reviewed the association between Chlamydia pneumoniae, an atypical respiratory pathogen, and atherosclerosis in detail. Chapter 2 introduced the ‘Chlamydia pneumoniae in elderly patients with stroke’ or ‘C-PEPS’ study from which published works in subsequent chapters of this thesis were based. The C-PEPS was a case-control study that investigated the seroprevalence of C pneumoniae in 100 elderly acute stroke and transient ischaemic attack (TIA) patients versus 87 control medical patients. The C-PEPS study showed a high seroprevalence (immunoglobulin IgG) of C pneumoniae infection in both cases and controls. There was no significant association between C pneumoniae seropositivity and stroke / TIA. Chapter 3 presented a study that investigated the reproducibility of a commercial enzyme linked immunosorbent assay (ELISA) kit (SeroCP, Savyon) used in the CPEPS study. The study concluded that SeroCP ELISA had a good reproducibility for the detection of C pneumoniae IgA and moderately good reproducibility for C pneumoniae IgG and IgM. In chapter 4, the ‘Mycoplasma pneumoniae in elderly patients with stroke’ or ‘MPEPS’ case-control study was based on the same cohort of patients as in the C-PEPS study. The M-PEPS study showed a high seroprevalence of M pneumoniae, another atypical respiratory pathogen, in the cohort. However, the study had ruled out M pneumoniae as a major risk factor for stroke / TIA. In chapter 5, the ‘Legionella pneumophila in elderly patients with stroke’ or ‘L-PEPS’ was another case-control study based on the same cohort of patients as in the C-PEPS 3 study. The L-PEPS study established that there was no statistical difference between the seroprevalence of L pneumophila, another atypical respiratory pathogen, in both the stroke / TIA patients and control medical patients. However, when the results of C-PEPS, M-PEPS and L-PEPS studies were analysed together, it appeared that the aggregate number or infectious burden of chronic atypical respiratory infections was associated with the risk of stroke / TIA. Chapter 6 presented a pilot study that investigated the seroprevalence of Coxiella burnetii, another atypical respiratory pathogen, in the same cohort of patients as in the C-PEPS study. Due to very low seropositivity and zero counts, a conclusion could not be made on any association between C burnetii seropositivity and stroke / TIA. Chapter 7 presented the electrocardiographic findings such as rhythms and ischaemic changes of the same cohort of patients as in the C-PEPS study. Atrial fibrillation was the commonest rhythm abnormality in both elderly stroke / TIA cases and medical controls. After adjusment for background history of ischaemic heart disease, there was a statistical trend to suggest an association between ischaemic elctrocardiographic changes and stroke / TIA. Chapter 8 presented a case-control study that investigated the relationsips between socioeconomic deprivation (SED) status, atypical respiratory infections and survival outcome in the same cohort of patients as in the C-PEPS study. The SED status of stroke / TIA cases and controls were similar. Although an association between acute atypical respiratory infection and SED was only found in the control medical patients, acute atypical respiratory infectious burden was found to associate with income deprivation in the whole cohort of elderly stroke / TIA and medical patients. SED on its own had only a modest effect on the association between chronic atypical respiratory infectious burden and stroke / TIA. Elderly patients’ duration of survival after an acute stroke / TIA appeared not to be affected by their background SED status. Chapter 9 was the concluding chapter. The main findings of the published works submitted for the thesis were summarised and discussed. Some directions for future research were also discussed.

clanata@iin.sld.pe / Introduction: Pneumonia and diarrhoea are leading causes of death in children. There is a need to develop effective interventions. Objective: We present the design and baseline findings of a community-randomised controlled trial in rural Peru to evaluate the health impact of an Integrated Home-based Intervention Package in children aged 6 to 35 months. Methods: We randomised 51 communities. The intervention was developed through a community-participatory approach prior to the trial. They comprised the construction of improved stoves and kitchen sinks, the promotion of hand washing, and solar drinking water disinfection (SODIS). To reduce the potential impact of non-blinding bias, a psychomotor stimulation intervention was implemented in the control arm. The baseline survey included anthropometric and socio-economic characteristics. In a sub-sample we determined the level of faecal contamination of drinking water, hands and kitchen utensils and the prevalence of diarrhoegenic Escherichia coli in stool specimen. Results: We enrolled 534 children. At baseline all households used open fires and 77% had access to piped water supplies. E. coli was found in drinking water in 68% and 64% of the intervention and control households. Diarrhoegenic E. coli strains were isolated from 45/139 stool samples. The proportion of stunted children was 54%. Conclusions: Randomization resulted in comparable study arms. Recently, several critical reviews raised major concerns on the reliability of open health intervention trials, because of uncertain sustainability and non-blinding bias. In this regard, the presented trial featuring objective outcome measures, a simultaneous intervention in the control communities and a 12- month follow up period will provide valuable evidence. / This study received financial support of the UBS Optimus Foundation, through a grant given to the IIN and Swiss TPH. The sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation, review, or approval of the manuscript. / Revisión por pares