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1.
Med Vet Entomol ; 38(2): 189-204, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38469668

ABSTRACT

We used entire mitochondrial (mt) genome sequences (14.5-15 kbp) to resolve the phylogeny of the four main lineages of the Haematobothrion ticks: Alloceraea, Archaeocroton, Bothriocroton and Haemaphysalis. In our phylogenetic trees, Alloceraea was the sister to Archaeocroton sphenodonti, a tick of an archetypal reptile, the tuatara, from New Zealand, to the exclusion of the rest of the species of Haemaphysalis. The mt genomes of all four of the Alloceraea species that have been sequenced so far had a substantial insert, 132-312 bp, between the tRNA-Glu (E) gene and the nad1 gene in their mt genomes. This insert was not found in any of the other eight subgenera of Haemaphysalis. The mt genomes of 13 species of Haemaphysalis from NCBI GenBank were added to the most recent data set on Haemaphysalis and its close relatives to help resolve the phylogeny of Haemaphysalis, including five new subgenera of Haemaphysalis not previously considered by other authors: Allophysalis (structurally primitive), Aboimisalis (structurally primitive), Herpetobia (structurally intermediate), Ornithophysalis (structurally advanced) and Segalia (structurally advanced). We elevated Alloceraea Schulze, 1919 to the status of genus because Alloceraea Schulze, 1919 is phylogenetically distinct from the other subgenera of Haemaphysalis. Moreover, we propose that the subgenus Allophysalis is the sister to the rest of the Haemaphysalis (14 subgenera) and that the 'structurally primitive' subgenera Hoogstraal and Kim comprise early diverging lineages. Our matrices of the pairwise genetic difference (percent) of mt genomes and partial 16S rRNA sequences indicated that the mt genome sequence of Al. kitaokai (gb# OM368280) may not be Al. kitaokai Hoogstraal, 1969 but rather another species of Alloceraea. In a similar way, the mt genome sequence of H. (Herpetobia) nepalensis Hoogstraal, 1962 (gb# NC_064124) was only 2% genetically different to that of H. (Allophysalis) tibetensis Hoogstraal, 1965 (gb# OM368293): this indicates to us that they are the same species. Alloceraea cretacea may be better placed in a genus other than Alloceraea Schulze, 1919. Reptiles may have been the host to the most recent common ancestor of Archaeocroton and Alloceraea.


Subject(s)
Genome, Mitochondrial , Ixodidae , Phylogeny , Animals , Ixodidae/genetics , Ixodidae/classification
2.
Acta Trop ; 254: 107197, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38554993

ABSTRACT

Dermacentor (Indocentor) auratus Supino, 1897 occurs in many regions of Southeast Asia and South Asia. In many regions of Southeast Asia and South Asia, targeted tick sampling and subsequent screening of collected D. auratus ticks have detected pathogenic bacteria and viruses in D. auratus. These disease-causing pathogens that have been detected in D. auratus include Anaplasma, Bartonella, Borrelia, Rickettsia (including spotted fever group rickettsiae), African swine fever virus, Lanjan virus, and Kyasanur forest disease virus. Although D. auratus predominantly infests wild pigs, this tick is also an occasional parasite of humans and other animals. Indeed, some 91 % of human otoacariasis cases in Sri Lanka were due to infestation by D. auratus. With the propensity of this tick to feed on multiple species of hosts, including humans, and the detection of pathogenic bacteria and viruses from this tick, D. auratus is a tick of medical, veterinary, and indeed zoonotic concern. The geographic range of this tick, however, is not well known. Therefore, in the present paper, we used the species distribution model, BIOCLIM, to project the potential geographic range of D. auratus, which may aid pathogen and tick-vector surveillance. We showed that the potential geographic range of D. auratus is far wider than the current geographic distribution of this tick, and that regions in Africa, and in North and South America seem to have suitable climates for D. auratus. Interestingly, in Southeast Asia, Borneo and Philippines also have suitable climates for D. auratus, but D. auratus has not been found in these regions yet despite the apparent close proximity of these regions to Mainland Southeast Asia, where D. auratus occurs. We thus hypothesize that the geographic distribution of D. auratus is largely dependent on the movement of wild pigs and whether or not these wild pigs are able to overcome dispersal barriers. We also review the potential pathogens and the diseases that may be associated with D. auratus and provide an updated host index for this tick.


Subject(s)
Dermacentor , Animals , Dermacentor/microbiology , Dermacentor/virology , Humans , Tick-Borne Diseases/epidemiology , Tick-Borne Diseases/veterinary , Tick-Borne Diseases/microbiology , Tick-Borne Diseases/virology , Swine , Tick Infestations/veterinary , Tick Infestations/epidemiology , Asia, Southeastern/epidemiology , Rickettsia/isolation & purification , Rickettsia/classification , Asia , Zoonoses/parasitology
3.
Int J Parasitol ; 54(8-9): 453-462, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38609074

ABSTRACT

The tropical brown dog tick, Rhipicephalus linnaei, is a tick of much medical, veterinary, and zoonotic importance. This tick has a nearly world-wide distribution due to its ability to survive and propagate in kennels and houses. Rhipicephalus linnaei is the vector of Ehrlichia canis, the causative agent of canine monocytic ehrlichiosis, an often debilitating disease of canids and, occasionally, humans. To prevent incursion of E. canis into Australia, dogs entering Australia have been required to have a negative immunofluorescence antibody test for E. canis. In May 2020 however, E. canis was detected in Western Australia. The detection of E. canis in Australia prompted disease investigation and concerted surveillance for R. linnaei and E. canis in regions across Australia. These investigations revealed that R. linnaei was established far beyond the previously recognised geographic range limits of this tick. In the present paper, using records from various collections, published data, and data from our network of veterinarian collaborators and colleagues, we update the current geographic range of R. linnaei in Australia. Our analyses revealed that the geographic range of R. linnaei in Australia is much wider than was previously supposed, particularly in Western Australia, and in South Australia. We also map, for the first time, where E. canis has been detected in Australia. Last, we discuss the possible routes of incursion and subsequently the factors which may have aided the spread of E. canis in Australia which led to the establishment of this pathogen in Australia.


Subject(s)
Dog Diseases , Ehrlichia canis , Ehrlichiosis , Rhipicephalus , Animals , Australia/epidemiology , Ehrlichia canis/isolation & purification , Dogs , Dog Diseases/parasitology , Dog Diseases/epidemiology , Ehrlichiosis/epidemiology , Ehrlichiosis/veterinary , Ehrlichiosis/transmission , Ehrlichiosis/history , Rhipicephalus/microbiology , Female , Male
4.
Vet Parasitol ; 331: 110252, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39079236

ABSTRACT

The eastern paralysis tick, Ixodes holocyclus, is a tick of much veterinary importance in Australia. Each year, thousands of dogs and cats present to veterinary clinics and hospitals with signs of tick paralysis. In a previous paper, we constructed two models to explain prevalence and temporal distributions of tick paralysis cases presenting to emergency veterinary hospitals in South East Queensland (2009-2020) and the Northern Beaches of Sydney (1999-2017). The first model accounted for the intensity of the clinical burden of tick paralysis based on the prevalence of cases of tick paralysis in the tick paralysis season whereas the second model accounted for the start of the tick paralysis season. In the present paper, we test our models further, with much additional data from 2021 to 2023 (South East Queensland) and from 2018 to 2023 (Northern Beaches of Sydney). During the defined tick paralysis season in these locations, 10.3 % (3207 of 31,217) of veterinary-consultations were for tick paralysis. On average, predictions for the prevalence of cases of tick paralysis were 1.3 % (0.013) away from the actual prevalence whereas predictions for the start of the tick paralysis season were 1.7 weeks away from the actual start of the season. The prediction of the prevalence of tick paralysis cases was most accurate for Brisbane and least accurate for the Northern Beaches of Sydney whereas, curiously, the prediction for the start of the tick paralysis season was most accurate for the Northern Beaches of Sydney and least accurate for Brisbane. We re-fitted the models with the new data. We predict that about 10 % (Sunshine Coast), 5 % (Brisbane), 7 % (Gold Coast) and 12 % (Northern Beaches of Sydney) of veterinary-consultations in the tick paralysis season of 2024 will be cases of tick paralysis, resulting in a tick paralysis clinical burden intensity of similar magnitude to previous years. Such predictions allow for timely public education campaigns around the importance of prevention and appropriate resource planning for veterinary clinics.


Subject(s)
Dog Diseases , Seasons , Tick Paralysis , Weather , Animals , Tick Paralysis/epidemiology , Tick Paralysis/veterinary , Tick Paralysis/parasitology , Dog Diseases/epidemiology , Dog Diseases/parasitology , Dogs , Cats , Prevalence , Queensland/epidemiology , Ixodes/physiology , Cat Diseases/epidemiology , Cat Diseases/parasitology , Australia/epidemiology , Tick Infestations/veterinary , Tick Infestations/epidemiology
5.
Zootaxa ; 5410(1): 91-111, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38480255

ABSTRACT

We describe a new genus Cryptocroton n. gen. for Amblyomma papuanum Hirst, 1914, a tick of North Queensland, Australia, and Papua New Guinea.


Subject(s)
Ticks , Animals , Queensland , Amblyomma , Papua New Guinea , Australia
6.
Parasit Vectors ; 17(1): 139, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38500136

ABSTRACT

BACKGROUND: Amblyomma is the third most diversified genus of Ixodidae that is distributed across the Indomalayan, Afrotropical, Australasian (IAA), Nearctic and Neotropical biogeographic ecoregions, reaching in the Neotropic its highest diversity. There have been hints in previously published phylogenetic trees from mitochondrial genome, nuclear rRNA, from combinations of both and morphology that the Australasian Amblyomma or the Australasian Amblyomma plus the Amblyomma species from the southern cone of South America, might be sister-group to the Amblyomma of the rest of the world. However, a stable phylogenetic framework of Amblyomma for a better understanding of the biogeographic patterns underpinning its diversification is lacking. METHODS: We used genomic techniques to sequence complete and nearly complete mitochondrial genomes -ca. 15 kbp- as well as the nuclear ribosomal cluster -ca. 8 kbp- for 17 Amblyomma ticks in order to study the phylogeny and biogeographic pattern of the genus Amblyomma, with particular emphasis on the Neotropical region. The new genomic information generated here together with genomic information available on 43 ticks (22 other Amblyomma species and 21 other hard ticks-as outgroup-) were used to perform probabilistic methods of phylogenetic and biogeographic inferences and time-tree estimation using biogeographic dates. RESULTS: In the present paper, we present the strongest evidence yet that Australasian Amblyomma may indeed be the sister-group to the Amblyomma of the rest of the world (species that occur mainly in the Neotropical and Afrotropical zoogeographic regions). Our results showed that all Amblyomma subgenera (Cernyomma, Anastosiella, Xiphiastor, Adenopleura, Aponomma and Dermiomma) are not monophyletic, except for Walkeriana and Amblyomma. Likewise, our best biogeographic scenario supports the origin of Amblyomma and its posterior diversification in the southern hemisphere at 47.8 and 36.8 Mya, respectively. This diversification could be associated with the end of the connection of Australasia and Neotropical ecoregions by the Antarctic land bridge. Also, the biogeographic analyses let us see the colonization patterns of some neotropical Amblyomma species to the Nearctic. CONCLUSIONS: We found strong evidence that the main theater of diversification of Amblyomma was the southern hemisphere, potentially driven by the Antarctic Bridge's intermittent connection in the late Eocene. In addition, the subgeneric classification of Amblyomma lacks evolutionary support. Future studies using denser taxonomic sampling may lead to new findings on the phylogenetic relationships and biogeographic history of Amblyomma genus.


Subject(s)
Genome, Mitochondrial , Ixodidae , Ticks , Animals , Ixodidae/genetics , Phylogeny , Amblyomma
7.
Epilepsia ; 54(7): 1307-14, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23692434

ABSTRACT

PURPOSE: HLA-B*15:02 screening is recommended before starting carbamazepine in Han Chinese and Southeast Asians because the allele is strongly predictive of Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) induced by the drug. We examined whether other HLA-B alleles are also involved and whether the association extends to other antiepileptic drugs (AEDs). METHODS: Cases of SJS/TEN induced by any AEDs were recruited and matched (1:5) with AED-tolerant controls. Carrier rates of HLA-B alleles, determined by direct sequencing, were compared between cases and controls. Results were meta-analyzed with previous studies to examine the associations between HLA-B*15:02 and SJS/TEN induced by phenytoin and lamotrigine. KEY FINDINGS: A total of 55 cases (27 carbamazepine, 15 phenytoin, 6 lamotrigine, 7 other AEDs) and 275 controls were recruited. In drug-specific analysis, the carrier rate of HLA-B*15:02 was significantly higher in carbamazepine-SJS/TEN cases compared with carbamazepine-tolerant controls (92.3% vs. 11.9%; p = 3.51 × 10(-18) ; odds ratio (OR) 89.25; 95% confidence interval (CI) 19.25-413.83), and also in phenytoin-SJS/TEN cases compared with phenytoin-tolerant controls (46.7% vs. 20.0%; p = 0.045; OR 3.50; 95% CI 1.10-11.18). Meta-analyses showed a strong association of HLA-B*15:02 with phenytoin-SJS/TEN (p < 3 × 10(-4) ; OR 4.26; 95% CI 1.93-9.39) and, to a lesser extent, lamotrigine-SJS/TEN (p = 0.03; OR 3.59; 95% CI 1.15-11.22). Compared with drug-tolerant controls, the carrier rates of HLA-B*40:01 and HLA-B*58:01 were lower in cases of SJS/TEN induced by carbamazepine (p = 0.004) and other AEDs (p = 0.009), respectively. SIGNIFICANCE: SJS/TEN induced by carbamazepine and phenytoin is strongly and moderately associated with HLA-B*15:02 in Han Chinese, respectively. Possible protective associations with HLA-B*40:01 and HLA-B*58:01 warrant further investigation.


Subject(s)
Anticonvulsants/adverse effects , Epilepsy/genetics , Genetic Predisposition to Disease , HLA-B Antigens/genetics , Skin Diseases/chemically induced , Skin Diseases/genetics , Adolescent , Adult , Aged , Asian People/ethnology , Asian People/genetics , Case-Control Studies , Child , Epilepsy/drug therapy , Female , Genetic Association Studies , Humans , Male , Meta-Analysis as Topic , Middle Aged , Retrospective Studies , Risk Factors , Stevens-Johnson Syndrome/chemically induced , Stevens-Johnson Syndrome/etiology , Stevens-Johnson Syndrome/genetics , Young Adult
8.
Int J Parasitol ; 53(1): 43-53, 2023 01.
Article in English | MEDLINE | ID: mdl-36462559

ABSTRACT

We studied 22,840 cases of tick paralysis in dogs and cats that were attributable to infestation with the eastern paralysis tick, Ixodes holocyclus. We report that the mortality rates from the holocyclotoxins of the tick or from euthanasia due to complications arising from tick paralysis in dogs and cats were 10% and 8%, respectively. The distribution of cases of tick paralysis among the 52 weeks of 22 years (1999 to 2020, inclusive) in four regions along the eastern coast of Australia revealed much about how the life-cycle of this tick varied among regions. The four regions in our study were: (i) Cairns, Innisfail, and surrounding postcodes in Far North Queensland; (ii) South East Queensland; (iii) Northern Beaches of Sydney in New South Wales; and (iv) the Shire of East Gippsland in Victoria. We found that the season of tick paralysis started earlier in more northerly latitudes than in more southerly latitudes. We also found that Victoria has two seasons of tick paralysis, one from approximately the third week of February to the first week of May, and another from approximately the third week of September to the third week of December, whereas all of the other regions we studied in eastern Australia only had one season of tick paralysis. When we studied the two seasons of tick paralysis in Victoria, we found a statistically significant negative correlation between the number of cases of tick paralysis between the two seasons: the more cases in one season, the fewer the cases in the next season. One possible explanation for the negative correlation may be immunity to I. holocyclus acquired by dogs and cats in the first season.


Subject(s)
Cat Diseases , Dog Diseases , Ixodes , Tick Paralysis , Cats , Animals , Dogs , New South Wales/epidemiology , Victoria , Queensland/epidemiology , Seasons , Tick Paralysis/epidemiology , Tick Paralysis/veterinary , Dog Diseases/epidemiology
9.
Ticks Tick Borne Dis ; 14(2): 102070, 2023 03.
Article in English | MEDLINE | ID: mdl-36455382

ABSTRACT

Hoogstraal and Kim (1985) proposed from morphology, three groups of Haemaphysalis subgenera: (i) the "structurally advanced"; (ii) the "structurally intermediate"; and (iii) the "structurally primitive" subgenera. Nuclear gene phylogenies, however, did not indicate monophyly of these morphological groups but alas, only two mitochondrial (mt) genomes from the "structurally intermediate" subgenera had been sequenced. The phylogeny of Haemaphysalis has not yet been resolved. We aimed to resolve the phylogeny of the genus Haemaphysalis, with respect to the subgenus Alloceraea. We presented 15 newly sequenced and annotated mt genomes from 15 species of ticks, five species of which have not been sequenced before, and four new 18S rRNA and 28S rRNA nuclear gene sequences. Our datasets were constructed from 10 mt protein-coding genes, cox1, and the 18S and 28S nuclear rRNA genes. We found a 132-bp insertion between tRNA-Glu (E) gene and the nad1 gene in the mt genome of Haemaphysalis (Alloceraea) inermis that resembles insertions in H. (Alloceraea) kitaokai and Rhipicephalus (Boophilus) geigyi. Our mt phylogenies had the three species of Amblyomma (Aponomma) we sequenced embedded in the main clade of Amblyomma: Am. (Aponomma) fimbriatum, Am. (Aponomma) gervaisi and Am. (Aponomma) latum. This is further support for the hypothesis that the evolution of eyes appears to have occurred in the most-recent-common-ancestor of Amblyocephalus (i.e. Amblyomminae plus Rhipicephalinae) and that eyes were subsequently lost in the most-recent-common-ancestor of the subgenus Am. (Aponomma). Either Africaniella transversale or Robertsicus elaphensis, or perhaps Af. transversale plus Ro. elaphensis, appear to be the sister-group to the rest of the metastriate Ixodida. Our cox1 phylogenies did not indicate monophyly of the "structurally primitive", "structurally intermediate" nor the "structurally advanced" groups of Haemaphysalis subgenera. Indeed, the subgenus Alloceraea may be the only monophyletic subgenus of the genus Haemaphysalis sequenced thus far. All of our mt genome and cox1 phylogenies had the subgenus Alloceraea in a clade that was separate from the rest of the Haemaphysalis ticks. If Alloceraea is indeed the sister to the rest of the Haemaphysalis subgenera this would resonate with the argument of Hoogstraal and Kim (1985), that Alloceraea was a subgenus of "primitive" Haemaphysalis. Alectorobius capensis from Japan had a higher genetic-identity to A. sawaii, which was also from Japan, than to the A. capensis from South Africa. This indicates that A. capensis from Japan may be a cryptic species with respect to the A. capensis from South Africa.


Subject(s)
Genome, Mitochondrial , Ixodidae , Rhipicephalus , Animals , Ixodidae/genetics , Phylogeny , Genes, rRNA , Rhipicephalus/genetics , Amblyomma/genetics
10.
Zootaxa ; 5325(4): 529-540, 2023 Aug 10.
Article in English | MEDLINE | ID: mdl-38220895

ABSTRACT

A new subgenus, Australixodes n. subgen., is described for the kiwi tick, Ixodes anatis Chilton, 1904. The subgenus Coxixodes Schulze, 1941 is validated for the platypus tick, Ixodes (Coxixodes) ornithorhynchi Lucas, 1846, sister group of the subgenus Endopalpiger Schulze, 1935. A phylogeny from mitochondrial genomes of 16 of the 22 subgenera of Ixodes (32 spp.) indicates, for the first time, the relationships of the subgenera of Ixodes Latreille, 1795, the largest genus of ticks.


Subject(s)
Genome, Mitochondrial , Ixodes , Ixodidae , Animals , Ixodes/genetics , Ixodidae/genetics , Phylogeny
11.
Int J Parasitol ; 51(4): 241-249, 2021 03.
Article in English | MEDLINE | ID: mdl-33513402

ABSTRACT

The eastern paralysis tick, Ixodes holocyclus, is an ectoparasite of medical and veterinary importance in Australia. The feeding of I. holocyclus is associated with an ascending flaccid paralysis which kills many dogs and cats each year, with the development of mammalian meat allergy in some humans, and with the transmission of Rickettsia australis (Australian scrub typhus) to humans. Although I. holocyclus has been well studied, it is still not known exactly why this tick cannot establish outside of its present geographic distribution. Here, we aim to account for the presence as well as the absence of I. holocyclus in regions of Australia. We modelled the climatic requirements of I. holocyclus with two methods, CLIMEX, and a new envelope-model approach which we name the 'climatic-range method'. These methods allowed us to account for 93% and 96% of the geographic distribution of I. holocyclus, respectively. Our analyses indicated that the geographic range of I. holocyclus may not only shift south towards Melbourne, but may also expand in the future, depending on which climate-change scenario comes to pass.


Subject(s)
Cat Diseases , Dog Diseases , Ixodes , Animals , Australia , Cats , Dogs , Food Hypersensitivity , Paralysis , Rickettsia
12.
Ticks Tick Borne Dis ; 12(5): 101758, 2021 09.
Article in English | MEDLINE | ID: mdl-34153869

ABSTRACT

The southern paralysis tick, Ixodes cornuatus, is a tick of veterinary and medical importance in Australia. We use two methods, CLIMEX, and an envelope-model approach which we name the 'climatic-range method' to study the climatic requirements of I. cornuatus and thus to attempt to account for the geographic distribution of I. cornuatus. CLIMEX and our climatic-range method allowed us to account for 94% and 97% of the records of I. cornuatus respectively. We also studied the host preferences of I. cornuatus which we subsequently used in conjunction with our species distribution methods to account for the presence and the absences of I. cornuatus across Australia. Our findings indicate that the actual geographic distribution of I. cornuatus is smaller than the potential geographic range of this tick, and thus, that there are regions in Australia which may be suitable for I. cornuatus where this tick has not been recorded. Although our findings indicate that I. cornuatus might be able to persist in these currently unoccupied regions, our findings also indicate that the potential geographic range of I. cornuatus may shrink by 51 to 76% by 2090, depending on which climate change scenario comes to pass.


Subject(s)
Animal Distribution , Climate Change/statistics & numerical data , Marsupialia/parasitology , Models, Statistical , Animals , Australia , Host Specificity , Host-Parasite Interactions , Humans , Ixodes , Mammals/parasitology , Tick Paralysis/epidemiology , Tick Paralysis/veterinary
13.
Obstet Gynecol ; 105(3): 557-62, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15738024

ABSTRACT

OBJECTIVE: We sought to estimate the rate of spontaneous resolution of asymptomatic Chlamydia trachomatis in pregnancy and to evaluate factors associated with its resolution. METHODS: A cohort of women enrolled in a large multicenter randomized bacterial vaginosis antibiotic trial (metronidazole versus placebo) that, when randomly allocated, had asymptomatic C trachomatis diagnosed by urine ligase chain reaction (from frozen archival specimens) between 16(0/7) and 23(6/7) weeks were included. The urine ligase chain reaction is a highly accurate predictor of genital tract chlamydial infection. A follow-up ligase chain reaction was performed between 24(0/7) and 29(6/7) weeks. RESULTS: A total of 1,953 women were enrolled in the original antibiotic trial; 1,547 (79%) had ligase chain reaction performed both at randomization and follow-up. Women receiving antibiotics effective against Chlamydia between randomization and follow-up or having symptomatic Chlamydia infection were excluded (26 women). Of the 140 women (9%) who were diagnosed as positive via the initial ligase chain reaction assay, 61 (44%) had spontaneous resolution of Chlamydia by the follow-up ligase chain reaction assay. Factors associated with spontaneous resolution included older age (P = .02), more than 5 weeks from randomization to follow-up (P = .02), and a greater number of lifetime sexual partners (P = .02). Using a logistic regression model, maternal age and a greater-than-5-week follow-up interval remained significant; for every 5-year increase in maternal age, the odds of a positive result on the ligase chain reaction test at follow-up decreased by 40% (odds ratio 0.6; 95% confidence interval 0.4-0.9). Race, substance abuse, parity, and treatment with metronidazole were not associated with spontaneous resolution. Gram stain score and vaginal pH at randomization and follow-up also were not associated. CONCLUSION: The prevalence of asymptomatic C trachomatis in pregnancy was 9%; infection resolved spontaneously in almost half of these women. The association of older age and increasing time interval to spontaneous resolution of Chlamydia is consistent with a host immune-response mechanism.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia trachomatis , Pregnancy Complications, Infectious/diagnosis , Adult , Anti-Infective Agents/therapeutic use , Chlamydia Infections/complications , Double-Blind Method , Female , Humans , Ligase Chain Reaction , Metronidazole/therapeutic use , Pregnancy , Remission, Spontaneous , Vaginosis, Bacterial/complications , Vaginosis, Bacterial/diagnosis , Vaginosis, Bacterial/drug therapy
14.
J Clin Epidemiol ; 47(2): 119-30, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8113821

ABSTRACT

This study examines the associations between race, birth weight, and mortality from endogenous causes for all singleton births born in 1984-1987 in a 20-county region of North Carolina. A more detailed analysis of preterm low birth weight infants examines these associations according to the proximate medical causes (medical etiology) of the preterm birth. Overall, black infants were found to have approximately twice the mortality risk of white infants. Most of the excess black mortality risk is explained by the larger proportion of black infants born at lower birth weights. The pattern of race differences in infant mortality by birth weight generally replicates the results of earlier studies, but the relative risk ratios within specific birth weight categories are smaller than previously reported. Among preterm low birth weight infants, the association between race and endogenous mortality differs within categories of medical etiology. The mortality risk is the same for black and white infants born preterm due to premature rupture of the membranes (PROM), lower for black infants born preterm due to medical problems, and higher for black infants born preterm due to idiopathic premature labor (IPL).


Subject(s)
Black People , Infant Mortality , Infant, Low Birth Weight , Infant, Premature , White People , Adult , Birth Weight , Female , Fetal Membranes, Premature Rupture/complications , Humans , Infant, Newborn , Male , North Carolina/epidemiology , Obstetric Labor, Premature/complications , Odds Ratio , Pregnancy , Regression Analysis , Risk Factors
15.
Obstet Gynecol ; 74(5): 734-8, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2812649

ABSTRACT

Preterm premature rupture of the membranes (PROM) is a common predecessor of preterm or low birth weight (LBW) birth, yet the risk of preterm PROM is presently unpredictable. Numerous infectious organisms that change the normal vaginal milieu have been associated with preterm PROM. Because these organisms alter vaginal pH, the use of pH was evaluated as a potential marker for women at increased risk for preterm PROM. Among 115 women at high risk for an LBW birth, those with a mean vaginal pH above 4.5 had a threefold increased risk of preterm PROM as compared with those with a mean pH of 4.5 or lower. Vaginal pH may be a useful marker to predict a woman's risk for preterm PROM.


Subject(s)
Fetal Membranes, Premature Rupture/diagnosis , Vagina/metabolism , Female , Humans , Hydrogen-Ion Concentration , Infant, Low Birth Weight , Infant, Newborn , Pregnancy , Risk Factors , Vaginal Smears
16.
Obstet Gynecol ; 86(5): 853-7, 1995 Nov.
Article in English | MEDLINE | ID: mdl-7566864

ABSTRACT

Scholarship in academic medicine includes the discovery of new knowledge as well as the integration, application, and teaching of existing knowledge. Although all components are vital, the rewards for each may vary considerably. Many medical educators have recommended that the teaching of medical students be given the same level of esteem traditionally awarded to research and patient care, and that the same level of excellence must be expected from teachers as from researchers and clinicians. Common facets of three successful reward systems in place include documenting quality as well as quantity; rewarding all excellent teachers, not just "the best"; and publicizing the rewards to students, peers, and administrators.


Subject(s)
Education, Medical, Undergraduate , Teaching , Faculty, Medical , Humans
17.
Obstet Gynecol ; 91(2): 165-8, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9469269

ABSTRACT

OBJECTIVE: To determine side effect profiles and cure rates of azithromycin compared with erythromycin in the treatment of chlamydial cervicitis complicating pregnancy. METHODS: Pregnant patients with positive DNA antigen assays for Chlamydia trachomatis were randomized to either azithromycin, 1 g oral slurry in a single dose, or erythromycin, 500 mg every 6 hours for 7 days. Repeat assays were planned for 3 weeks after therapy. Side effects, compliance, and treatment efficacy were assessed. RESULTS: One hundred six women were enrolled, and eighty-five women completed the protocol. Significantly fewer gastrointestinal side effects were noted in the azithromycin group than in the erythromycin group (11.9% versus 58.1%, P < or = .01). Enhanced compliance was noted with azithromycin, because it was given in a single observed dose. Similar treatment efficacy was noted between azithromycin and erythromycin (88.1% versus 93.0%, P > .05). CONCLUSION: Compared with erythromycin, azithromycin is associated with significantly fewer gastrointestinal side effects in pregnancy. This association, along with the ease of administration and similar efficacy, suggests that azithromycin should be considered for the initial treatment of chlamydial cervicitis in pregnancy.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Chlamydia Infections/drug therapy , Chlamydia trachomatis , Erythromycin/therapeutic use , Pregnancy Complications, Infectious/drug therapy , Uterine Cervicitis/drug therapy , Adult , Anti-Bacterial Agents/adverse effects , Azithromycin/adverse effects , Erythromycin/adverse effects , Female , Humans , Pregnancy
18.
Obstet Gynecol ; 69(3 Pt 2): 441-4, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3808520

ABSTRACT

Anterior sacral meningocele is a rare abnormality. Only 14 cases of it have been reported in association with pregnancy. Of those 14 patients, three died as a result of rupture of the meningocele during labor and postpartum. A new case is presented; the clinical presentation, the diagnosis, and treatment are discussed. The obstetric management of the case is discussed and a plan for management is suggested.


Subject(s)
Meningocele/etiology , Pregnancy Complications/etiology , Sacrum/abnormalities , Adult , Female , Headache/etiology , Humans , Meningocele/diagnostic imaging , Pregnancy , Pregnancy Complications/diagnostic imaging , Radiography , Sacrum/diagnostic imaging , Uterus/abnormalities
19.
Obstet Gynecol ; 69(3 Pt 1): 317-22, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3822278

ABSTRACT

Seventy-four patients in preterm labor at 20-35 weeks' gestation were randomly assigned to receive ritodrine (N = 36) or ritodrine plus magnesium sulfate treatment (N = 38) for tocolysis. Ten did not complete therapy and were excluded from analysis. Nineteen of 32 patients (59%) in the ritodrine plus magnesium sulfate group were successfully treated, compared with only 11 of 32 patients (34%) in the ritodrine-only group (P less than .05). Of the 21 patients who failed to respond to the initial ritodrine treatment, 16 received intravenous magnesium sulfate supplemental therapy; 75% of this group were treated successfully. The frequency of adverse maternal and fetal side effects did not differ between the treatment groups. In the combined group compared with the ritodrine group, the dose requirements for ritodrine therapy as well as the total duration of treatment for both ritodrine and magnesium sulfate were reduced significantly. We conclude that concurrent administration of ritodrine and magnesium sulfate is more efficacious than ritodrine alone and does not appear to increase the frequency of adverse side effects.


Subject(s)
Magnesium Sulfate/therapeutic use , Obstetric Labor, Premature/prevention & control , Ritodrine/therapeutic use , Drug Therapy, Combination , Female , Humans , Pregnancy , Prospective Studies , Random Allocation
20.
Obstet Gynecol ; 88(2): 216-20, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8692505

ABSTRACT

OBJECTIVE: To evaluate the efficacy of intrapartum prophylactic administration of ampicillin-sulbactam in reducing intraamniotic infection and postpartum endometritis in patients with meconium-stained amniotic fluid (AF). METHODS: Patients with intrapartum meconium-stained AF were randomized to receive either ampicillin-sulbactam or normal saline (placebo) intravenously at the time of diagnosis of meconium and every 6 hours until delivery. The outcomes of the two groups were compared with respect to intra-amniotic infection and postpartum endometritis. RESULTS: During the study period, 332 patients with meconium-stained AF were approached for participation, and 120 patients met inclusion criteria and were enrolled. Patient demographics, labor, and delivery characteristics were similar. Ampicillin-sulbactam reduced the incidence of intra-amniotic infection from 23.3 to 6.7%, (P = .02; relative risk [RR] 0.48, 95% confidence interval [CI] 0.22-0.98). The incidence of postpartum endometritis was also reduced, but the difference was statistically nonsignificant (8.3 versus 16.7%, P = .16; RR 0.64, 95% CI 0.30-1.33). CONCLUSION: Prophylactic intravenous ampicillin-sulbactam significantly reduces intra-amniotic infection in patients with meconium-stained AF.


Subject(s)
Amniotic Fluid , Ampicillin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/prevention & control , Endometritis/prevention & control , Fetal Diseases/prevention & control , Meconium , Obstetric Labor Complications/prevention & control , Penicillins/therapeutic use , Sulbactam/therapeutic use , Adult , Confidence Intervals , Double-Blind Method , Female , Humans , Infant, Newborn , Pregnancy , Risk
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