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Clinical Infectious Diseases : An... Jan 2021Diphtheria is a vaccine-preventable disease that persists as a global health problem. An understanding of the pattern of disease is lacking in low- and middle-income...
BACKGROUND
Diphtheria is a vaccine-preventable disease that persists as a global health problem. An understanding of the pattern of disease is lacking in low- and middle-income countries such as the Philippines.
METHODS
We conducted a retrospective review of the clinical, microbiological, and epidemiological features of patients admitted with a clinical diagnosis of diphtheria to an infectious disease referral hospital in Metro Manila, the Philippines, between 2006 and 2017. Cases were mapped and the distribution was compared with population density. Corynebacterium diphtheriae isolates from between 2015 and 2017 were examined by multilocus sequence typing (MLST).
RESULTS
We studied 267 patients (range:12-54 cases/year) admitted between 2006 and 2017. The case fatality rate (CFR) was 43.8% (95% confidence interval, 37.8-50.0%). A higher number of cases and CFR was observed among children <10 years. Mortality was associated with a delayed admission to hospital and a lack of diphtheria antitoxin. Between 2015 and 2017 there were 42 laboratory-confirmed cases. We identified 6 multilocus sequence types (STs). ST-302 was the most common (17/34, 48.6%), followed by ST67 (7/34, 20%) and ST458 (5/34, 14%). Case mapping showed a wide distribution of diphtheria patients in Metro Manila. Higher case numbers were found in densely populated areas but with no apparent clustering of ST types.
CONCLUSIONS
Our analysis indicates that diphtheria remains endemic in Metro Manila and that the infection is frequently fatal in young children. Improved vaccine coverage and a sustainable supply of diphtheria antitoxin should be prioritized.
Topics: Child; Child, Preschool; Corynebacterium diphtheriae; Diphtheria; Humans; Multilocus Sequence Typing; Philippines; Retrospective Studies
PubMed: 32160282
DOI: 10.1093/cid/ciaa005 -
British Medical Journal Sep 1955
Topics: Diphtheria
PubMed: 13240222
DOI: 10.1136/bmj.2.4940.669 -
The National Medical Journal of India 1997
Topics: Conjunctivitis, Bacterial; Diphtheria; Humans
PubMed: 9401393
DOI: No ID Found -
The British Journal of General Practice... Dec 1995
Topics: Adult; Diphtheria; Diphtheria Toxoid; Humans
PubMed: 8745875
DOI: No ID Found -
Proceedings of the Royal Society of... Jun 1975
Topics: Diphtheria; Hemorrhage; Intubation, Intratracheal; Pneumothorax; Postoperative Complications; Respiratory Paralysis; Tracheal Diseases; Tracheal Neoplasms; Tracheal Stenosis; Tracheotomy
PubMed: 1208527
DOI: No ID Found -
Bulletin of the World Health... 1998
Topics: Child; Diphtheria; Diphtheria Toxoid; Global Health; Humans; Infection Control
PubMed: 10063690
DOI: No ID Found -
Emerging Infectious Diseases Nov 2019Corynebacterium ulcerans infection is emerging in humans. We conducted phylogenetic analyses of C. ulcerans and C. diptheriae, which revealed diverse diphtheria toxin in...
Corynebacterium ulcerans infection is emerging in humans. We conducted phylogenetic analyses of C. ulcerans and C. diptheriae, which revealed diverse diphtheria toxin in C. ulcerans. Diphtheria toxin diversification could decrease effectiveness of diphtheria toxoid vaccine and diphtheria antitoxin for preventing and treating illnesses caused by this bacterium.
Topics: Amino Acid Sequence; Corynebacterium; Diphtheria; Diphtheria Toxin; Diphtheria Toxoid; Genetic Variation; Humans; Japan; Mutation; Phylogeny; RNA, Ribosomal, 16S
PubMed: 31625851
DOI: 10.3201/eid2511.181455 -
PloS One 2022Haiti has been experiencing a resurgence of diphtheria since December 2014. Little is known about the factors contributing to the spread and persistence of the disease...
BACKGROUND
Haiti has been experiencing a resurgence of diphtheria since December 2014. Little is known about the factors contributing to the spread and persistence of the disease in the country. Geographic information systems (GIS) and spatial analysis were used to characterize the epidemiology of diphtheria in Haiti between December 2014 and June 2021.
METHODS
Data for the study were collected from official and open-source databases. Choropleth maps were developed to understand spatial trends of diphtheria incidence in Haiti at the commune level, the third administrative division of the country. Spatial autocorrelation was assessed using the global Moran's I. Local indicators of spatial association (LISA) were employed to detect areas with spatial dependence. Ordinary least squares (OLS) and geographically weighted regression (GWR) models were built to identify factors associated with diphtheria incidence. The performance and fit of the models were compared using the adjusted r-squared (R2) and the corrected Akaike information criterion (AICc).
RESULTS
From December 2014 to June 2021, the average annual incidence of confirmed diphtheria was 0.39 cases per 100,000 (range of annual incidence = 0.04-0.74 per 100,000). During the study period, diphtheria incidence presented weak but significant spatial autocorrelation (I = 0.18, p<0.001). Although diphtheria cases occurred throughout Haiti, nine communes were classified as disease hotspots. In the regression analyses, diphtheria incidence was positively associated with health facility density (number of facilities per 100,000 population) and degree of urbanization (proportion of urban population). Incidence was negatively associated with female literacy. The GWR model considerably improved model performance and fit compared to the OLS model, as indicated by the higher adjusted R2 value (0.28 v 0.15) and lower AICc score (261.97 v 267.13).
CONCLUSION
This study demonstrates that GIS and spatial analysis can support the investigation of epidemiological patterns. Furthermore, it shows that diphtheria incidence exhibited spatial variability in Haiti. The disease hotspots and potential risk factors identified in this analysis could provide a basis for future public health interventions aimed at preventing and controlling diphtheria transmission.
Topics: Diphtheria; Female; Haiti; Humans; Least-Squares Analysis; Spatial Analysis; Spatial Regression
PubMed: 35994502
DOI: 10.1371/journal.pone.0273398 -
Epidemiology and Infection Jan 2022Diphtheria is a potentially devastating disease whose epidemiology remains poorly described in many settings, including Madagascar. Diphtheria vaccination is delivered...
Diphtheria is a potentially devastating disease whose epidemiology remains poorly described in many settings, including Madagascar. Diphtheria vaccination is delivered in combination with pertussis and tetanus antigens and coverage of this vaccine is often used as a core measure of health system functioning. However, coverage is challenging to estimate due to the difficulty in translating numbers of doses delivered into numbers of children effectively immunised. Serology provides an alternative lens onto immunisation, but is complicated by challenges in discriminating between natural and vaccine-derived seropositivity. Here, we leverage known features of the serological profile of diphtheria to bound expectations for vaccine coverage for diphtheria, and further refine these using serology for pertussis. We measured diphtheria antibody titres in 185 children aged 6-11 months and 362 children aged 8-15 years and analysed them with pertussis antibody titres previously measured for each individual. Levels of diphtheria seronegativity varied among age groups (18.9% of children aged 6-11 months old and 11.3% of children aged 8-15 years old were seronegative) and also among the districts. We also find surprisingly elevated levels of individuals seropositive to diphtheria but not pertussis in the 6-11 month old age group suggesting that vaccination coverage or efficacy of the pertussis component of the DTP vaccine remains low or that natural infection of diphtheria may be playing a significant role in seropositivity in Madagascar.
Topics: Adolescent; Antibodies, Bacterial; Bordetella pertussis; Child; Corynebacterium diphtheriae; Diphtheria; Diphtheria-Tetanus-Pertussis Vaccine; Female; Humans; Immunization Programs; Immunoglobulin G; Infant; Madagascar; Male; Seroepidemiologic Studies; Vaccination Coverage; Whooping Cough
PubMed: 35229710
DOI: 10.1017/S0950268822000097 -
Microbiology Spectrum Aug 2022Diphtheria is rare in the United States. and many industrialized nations due to development of an effective vaccine, coupled with high vaccination coverage. Although...
Diphtheria is rare in the United States. and many industrialized nations due to development of an effective vaccine, coupled with high vaccination coverage. Although there is continued risk of importation and transmission of Corynebacterium diphtheriae, C. ulcerans has now become the dominant source of diphtheria cases among several European countries. Bearing this in mind, a better understanding of C. ulcerans biology is clearly needed. Here, we identified active transmission of toxigenic C. ulcerans among indoor- and outdoor-housed rhesus macaques based on diphtheria toxin-specific serology assays as well as direct isolation of C. ulcerans from a recently infected animal. In addition to animal-to-animal transmission, we found serological evidence indicative of potential human transmission. Together, these results provide new details on natural Corynebacterium transmission among nonhuman primates and emphasizes the importance of maintaining high vaccination coverage to reduce the risk of potential zoonotic infection. C. ulcerans represents an emerging zoonotic agent of diphtheria, but little is known about its transmission or maintenance among animal reservoirs. In these studies, we identified diphtheria outbreaks among both outdoor- and indoor-housed rhesus macaques and isolated a toxigenic strain of C. ulcerans from a recently infected animal. Retrospective analysis indicated that toxigenic have been circulating among these primates for decades with the potential for rare zoonotic transmission to humans.
Topics: Animals; Corynebacterium; Diphtheria; Humans; Macaca mulatta; Retrospective Studies
PubMed: 35863003
DOI: 10.1128/spectrum.00894-22