title: The Association of Outer Ear Commensal Bacteria with Otitis Media in Children

authors: White, Rebecca Katharine

subjects: Otitis media

abstract: Background:
Middle ear infections (otitis media) are a significant burden on children’s health. They are one of the more common childhood ailments and are responsible for about a third of children’s general practitioner visits. Three bacteria of the nasopharynx have been well documented as true pathogens of otitis media. These are Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. A newer bacterium, Alloiococcus otitidis, which is more difficult to culture than the initial three pathogens, was discovered in 1989 by Faden & Dryja. 
The pathogenicity of A. otitidis in otitis media is controversial, as is the association of two other bacteria, Turicella otitidis and Corynebacterium auris. These three bacteria are regarded as commensals of the outer ear canal, and how they move into the middle ear is subject to much debate. My hypothesis is that during a primary middle ear infection, commensal bacteria of the external ear canal may be able to move through the inflamed tympanic membrane and into the middle ear where they act as opportunistic pathogens. This may create a more persistent bacterial infection, with greater resistance to antibiotic therapies. 
Methods:
DNA was extracted directly from swabs of the outer ear canal and nasopharynx of children with otitis media and otitis-free controls, and from the middle ear exudates of the otitis media study group. This DNA was then amplified using primers specific for each of the organisms of interest. The presence of a specific PCR product, confirmed by DNA sequencing, indicated a positive result.
Swabs from each of the sites of interest were also grown on 10% Columbia blood agar, 10% Columbia chocolate agar and in BHI broth supplemented with foetal calf serum. These results gave further information on bacterial presence in New Zealand children beyond the six studied. 
Sau-PCR microbial community profiling was used to demonstrate the diversity of species present in the polymicrobial samples. DNA was restriction digested and the resulting banding patterns were compared between study sites, and study groups.
Results and Conclusions:
Moraxella species colonised the outer ear canal of control participants more regularly than the outer ear canal of otitis media patients (58% vs. 33%). This difference was found to be statistically significant (p= 0.0023). Differences between the colonisation of the outer ear canal and nasopharyngeal body sites were found at a statistically significant level in control participants with A. otitidis (p=0.0433), C. auris (p=0.0000), T. otitidis (p=0.0050) and Moraxella spp. (p=0.0005). Of the same body sites in otitis media patients, only the colonisation of C. auris (p=0.0002) and T. otitidis (p=0.0004) were found to be statistically significant. This shows that four of the six studied bacteria colonise both anatomical sites in otitis media patients in a similar manner (without statistical significance), as opposed to only two in the control participants.
Of the six bacterial species analysed using non-culture techniques, S. pneumoniae, H. influenzae and C. auris failed to be cultured. This may show that storage prior to analysis made samples less suitable for culture based research. A number of other species were cultured, with subsequent sequencing identifying them. This included species thought to be associated with a decreased risk of developing otitis media, found in both of the control participant nasopharynxes that were studied, and in only one nasopharynx from the otitis media group. A. otitidis was cultured regularly in outer ear samples, and one middle ear effusion.
Sau-PCR microbial profiling was an effective but crude indication of microbial diversity. Otitis media patient nasopharyngeal profiles resembled each other, with resemblance extending to the middle ear effusion profile. Control participant banding patterns within sites were similar, but this resemblance did not extend to the otitis media group profiles. Comparisons between the banding patterns from known bacterial species to those of unknown polymicrobial species were useful if the identifying species had a unique banding pattern, as with A. otitidis. Sau-PCR therefore proved useful in analysing the complexities that are polymicrobial samples, however identifications of these species by cloning proved unsuccessful.
Further research using all the techniques above with increased numbers of participants is necessary to substantiate results of this study. Information on antibiotic resistance, viral presence, and biofilm status could prove useful information in helping treat infection.

text: The Association of Outer Ear Commensal Bacteria with Otitis Media in Children Background:
Middle ear infections (otitis media) are a significant burden on children’s health. They are one of the more common childhood ailments and are responsible for about a third of children’s general practitioner visits. Three bacteria of the nasopharynx have been well documented as true pathogens of otitis media. These are Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. A newer bacterium, Alloiococcus otitidis, which is more difficult to culture than the initial three pathogens, was discovered in 1989 by Faden & Dryja. 
The pathogenicity of A. otitidis in otitis media is controversial, as is the association of two other bacteria, Turicella otitidis and Corynebacterium auris. These three bacteria are regarded as commensals of the outer ear canal, and how they move into the middle ear is subject to much debate. My hypothesis is that during a primary middle ear infection, commensal bacteria of the external ear canal may be able to move through the inflamed tympanic membrane and into the middle ear where they act as opportunistic pathogens. This may create a more persistent bacterial infection, with greater resistance to antibiotic therapies. 
Methods:
DNA was extracted directly from swabs of the outer ear canal and nasopharynx of children with otitis media and otitis-free controls, and from the middle ear exudates of the otitis media study group. This DNA was then amplified using primers specific for each of the organisms of interest. The presence of a specific PCR product, confirmed by DNA sequencing, indicated a positive result.
Swabs from each of the sites of interest were also grown on 10% Columbia blood agar, 10% Columbia chocolate agar and in BHI broth supplemented with foetal calf serum. These results gave further information on bacterial presence in New Zealand children beyond the six studied. 
Sau-PCR microbial community profiling was used to demonstrate the diversity of species present in the polymicrobial samples. DNA was restriction digested and the resulting banding patterns were compared between study sites, and study groups.
Results and Conclusions:
Moraxella species colonised the outer ear canal of control participants more regularly than the outer ear canal of otitis media patients (58% vs. 33%). This difference was found to be statistically significant (p= 0.0023). Differences between the colonisation of the outer ear canal and nasopharyngeal body sites were found at a statistically significant level in control participants with A. otitidis (p=0.0433), C. auris (p=0.0000), T. otitidis (p=0.0050) and Moraxella spp. (p=0.0005). Of the same body sites in otitis media patients, only the colonisation of C. auris (p=0.0002) and T. otitidis (p=0.0004) were found to be statistically significant. This shows that four of the six studied bacteria colonise both anatomical sites in otitis media patients in a similar manner (without statistical significance), as opposed to only two in the control participants.
Of the six bacterial species analysed using non-culture techniques, S. pneumoniae, H. influenzae and C. auris failed to be cultured. This may show that storage prior to analysis made samples less suitable for culture based research. A number of other species were cultured, with subsequent sequencing identifying them. This included species thought to be associated with a decreased risk of developing otitis media, found in both of the control participant nasopharynxes that were studied, and in only one nasopharynx from the otitis media group. A. otitidis was cultured regularly in outer ear samples, and one middle ear effusion.
Sau-PCR microbial profiling was an effective but crude indication of microbial diversity. Otitis media patient nasopharyngeal profiles resembled each other, with resemblance extending to the middle ear effusion profile. Control participant banding patterns within sites were similar, but this resemblance did not extend to the otitis media group profiles. Comparisons between the banding patterns from known bacterial species to those of unknown polymicrobial species were useful if the identifying species had a unique banding pattern, as with A. otitidis. Sau-PCR therefore proved useful in analysing the complexities that are polymicrobial samples, however identifications of these species by cloning proved unsuccessful.
Further research using all the techniques above with increased numbers of participants is necessary to substantiate results of this study. Information on antibiotic resistance, viral presence, and biofilm status could prove useful information in helping treat infection.

year: 2012

title: Invertebrate food supplies and diet of blue duck on rivers in two regions of the North Island, New Zealand

authors: Collier, Kevin J.

subjects: blue duck

abstract: Benthic invertebrates and samples of blue duck faeces were collected in September 1988 from sites along Manganuiateao River, central North Island, and in November 1988 from seven rivers and streams on the East Cape. The occurrence of invertebrate taxa in the faeces varied within and between rivers, and within pairs of birds and family groups on the East Cape. In both regions, most blue duck had been consuming large proportions of cased caddisfly larvae. These are thought to have been mainly species of Helicopsyche and Pycnocentrodes at the East Cape sites and Beraeoptera roria at the Manganuiateao sites. Plecoptera larvae were also relatively abundant in blue duck faeces from most Manganuiateao sites in September. Overall, blue duck consumed proportionately more cased caddisfly larvae than occurred in the benthos (especially at the East Cape sites), but fewer Chironomidae, Coloburiscus humeralis and leptophlebiid mayfly (mainly Deleatidium spp.) larvae. Factors that affect the type of invertebrate foods available to blue duck at a particular site could include habitat heterogeneity, chance encounter, frequency and magnitude of floods, and geographic differences in the pool of invertebrate colonists. Apparent selectivity or avoidance of some benthic invertebrate groups by blue duck may partly reflect predator evasion by fast-moving invertebrate species, and differences in activity and distribution on upper stone surfaces where invertebrates should be more susceptible to predation by blue duck.

text: Invertebrate food supplies and diet of blue duck on rivers in two regions of the North Island, New Zealand Benthic invertebrates and samples of blue duck faeces were collected in September 1988 from sites along Manganuiateao River, central North Island, and in November 1988 from seven rivers and streams on the East Cape. The occurrence of invertebrate taxa in the faeces varied within and between rivers, and within pairs of birds and family groups on the East Cape. In both regions, most blue duck had been consuming large proportions of cased caddisfly larvae. These are thought to have been mainly species of Helicopsyche and Pycnocentrodes at the East Cape sites and Beraeoptera roria at the Manganuiateao sites. Plecoptera larvae were also relatively abundant in blue duck faeces from most Manganuiateao sites in September. Overall, blue duck consumed proportionately more cased caddisfly larvae than occurred in the benthos (especially at the East Cape sites), but fewer Chironomidae, Coloburiscus humeralis and leptophlebiid mayfly (mainly Deleatidium spp.) larvae. Factors that affect the type of invertebrate foods available to blue duck at a particular site could include habitat heterogeneity, chance encounter, frequency and magnitude of floods, and geographic differences in the pool of invertebrate colonists. Apparent selectivity or avoidance of some benthic invertebrate groups by blue duck may partly reflect predator evasion by fast-moving invertebrate species, and differences in activity and distribution on upper stone surfaces where invertebrates should be more susceptible to predation by blue duck.

year: 1991

title: Keepa Te Wharau: a Ngati Rahiri rangatira

authors: Hart, Philip

abstract: Keepa Te Wharau’s whakapapa linked him, unusually, to both Ngati Maru and Ngati Haua. Through these connections he was associated with the Te Aroha district from an early age, visiting it on several occasions and even cultivating there, briefly. When the block was before the land court he gave evidence – though his evidence in a later succession case was clearly wrong, deliberately so. Having interests in several blocks of land, he falsely claimed not to have received money for the Aroha Block, using the excuse of drunkenness, for which he was before the court on several occasions. He would sell land, as would his children, to meet living expenses. He invested in two goldfields, Thames and Te Aroha, very modestly. A leading rangatira, he was notable for his loyalty to the Crown.

text: Keepa Te Wharau: a Ngati Rahiri rangatira Keepa Te Wharau’s whakapapa linked him, unusually, to both Ngati Maru and Ngati Haua. Through these connections he was associated with the Te Aroha district from an early age, visiting it on several occasions and even cultivating there, briefly. When the block was before the land court he gave evidence – though his evidence in a later succession case was clearly wrong, deliberately so. Having interests in several blocks of land, he falsely claimed not to have received money for the Aroha Block, using the excuse of drunkenness, for which he was before the court on several occasions. He would sell land, as would his children, to meet living expenses. He invested in two goldfields, Thames and Te Aroha, very modestly. A leading rangatira, he was notable for his loyalty to the Crown.

year: 2016