exudates and Diphtheria

Diphtheria is an acute infectious disease caused by Corynebacterium diphtheriae. Although the incidence of diphtheria worldwide has rapidly declined following the largely successful diphtheria toxoid-based vaccines, concerns persist for those who were unvaccinated or incompletely vaccinated. In this report, we describe a recent diphtheria outbreak in Malaysia involving four confirmed diphtheria cases.. The outbreak investigation efforts and epidemiological characteristics of a diphtheria outbreak in Malaysia are described. For all suspected cases, swabs were taken and sent for isolation of Corynebacterium diphtheriae and confirmation of toxigenic strains.. The index case was a two-year-old child living with his family in a welfare home. Following contact tracing efforts and investigation for suspected cases, seven samples came back as culture positive for Corynebacterium diphtheriae. Confirmation of toxigenic strains was performed using PCR and Elek's test, which showed 100% correlation in positivity for four of the samples. All four confirmed cases were below 18 years of age, and three of them did not have complete vaccination history (two unvaccinated, one unknown). The index case eventually succumbed due to severe diphtheria with multiorgan failure while all the other cases were discharged healthy.. In Malaysia, despite good vaccination coverage, sporadic diphtheria outbreaks still occur. The rising trend of cases reported over the recent years underscores the need to remain vigilant. Addressing pockets of unvaccinated children and potential waning immunity levels in the population remains pivotal.

Topics: Child; Child, Preschool; Corynebacterium; Corynebacterium diphtheriae; Diphtheria; Disease Outbreaks; Humans; Malaysia; Public Health

Despite high childhood immunization coverage, sporadic cases of diphtheria have been reported in Malaysia in recent years. This study aims to evaluate the seroprevalence of diphtheria among the Malaysian population.. A total of 3317 respondents age 2 years old to 60 years old were recruited in this study from August to November 2017. Enzyme-linked immunosorbent assay (ELISA) was used to measure the level of IgG antibody against the toxoid of C. diphtheriae in the blood samples of respondents. We classified respondent antibody levels based on WHO definition, as protective (≥0.1 IU/mL) and susceptible (< 0.1 IU/mL) to C. diphtheriae infection.. Among the 3317 respondents, 57% were susceptible (38.1% of children and 65.4% of adults) and 43% (61.9% of children and 34.6% of adults) had protective antibody levels against diphtheria. The mean antibody level peaked among individuals aged 1-2 years old (0.59 IU/mL) and 6-7 years old (0.64 IU/mL) but generally decreased with age, falling below 0.1 IU/mL at around 4-6 years old and after age 20 years old. There was a significant association between age [Children: χ. About 57% of the Malaysian population have inadequate immunity against diphtheria infection. This is apparently due to waning immunity following childhood vaccination without repeated booster vaccination in adults. Children at age 5-6 years old are particularly vulnerable to diphtheria infection. The booster vaccination dose normally given at 7 years should be given earlier, and an additional booster dose is recommended for high-risk adults.

Topics: Adolescent; Adult; Antibodies, Bacterial; Child; Child, Preschool; Corynebacterium diphtheriae; Diphtheria; Diphtheria Toxoid; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin G; Infant; Malaysia; Male; Middle Aged; Seroepidemiologic Studies; Young Adult

Sporadic diphtheria cases in Malaysia have remained low in number since the 1990s. However, in 2016 a total of 31 cases were reported nationwide and to investigate this we performed molecular characterization of 30 Corynebacterium diphtheriae isolates collected from 1981 to 2016 using multilocus sequence typing (MLST). C. diphtheriae isolates were identified and biotyped using the API Coryne kit, while the toxigenicity was determined by PCR and the Elek test. All of the 2016 isolates belonged to biotype mitis, caused respiratory diphtheria and were toxigenic strains. MLST analysis identified 17 sequence types (STs), including 11 new ones. ST453 was the most common clone (7/30, 23.3 %), followed by ST141 (5/30, 16.7 %), ST451 (3/30, 10.0 %) and ST248 (2/30, 6.7 %). The clones identified in 2016 had not been detected in previous isolations and they were phylogenetically distinct. Our results suggest that the diphtheria cases in 2016 were caused by the emergence and spread of new clones in Malaysia.

Topics: Adolescent; Adult; Bacterial Typing Techniques; Child; Child, Preschool; Corynebacterium diphtheriae; Diphtheria; Humans; Infant; Malaysia; Multilocus Sequence Typing; Phylogeny; Young Adult

In November 2016, a 28-year-old Malay man presented to the emergency department in respiratory distress, with a history of fever and sore throat. A clinical diagnosis of acute diphtheria was made and the patient was isolated and ventilated in the intensive care unit, and received diphtheria antitoxin and intravenous antibiotics. Initial laboratory findings failed to confirm diphtheria, leading to discontinuation of antibiotics and quarantine. Public health measures were reinstated after a reference laboratory cultured Corynebacterium diphtheriae. Although there was no contact with ill persons, investigation revealed incomplete immunisation history, and injection of high dose steroids prior to onset of symptoms.

Topics: Acute Disease; Adult; Anti-Bacterial Agents; Corynebacterium diphtheriae; Diphtheria; Diphtheria Antitoxin; Drug Therapy, Combination; Humans; Malaysia; Male

There is a lack of study in Corynebacterium diphtheriae isolates in Malaysia. The alarming surge of cases in year 2016 lead us to evaluate the local clinical C. diphtheriae strains in Malaysia. We conducted single nucleotide polymorphism phylogenetic analysis on the core and pan-genome as well as toxin and diphtheria toxin repressor (DtxR) genes of Malaysian C. diphtheriae isolates from the year 1986-2016.. The comparison between core and pan-genomic comparison showed variation in the distribution of C. diphtheriae. The local isolates portrayed a heterogenous trait and a close relationship between Malaysia's and Belarus's, Africa's and India's strains were observed. A toxigenic C. diphtheriae clone was noted to be circulating in the Malaysian population for nearly 30 years and from our study, the non-toxigenic and toxigenic C. diphtheriae strains can be differentiated significantly into two large clusters, A and B respectively. Analysis against vaccine strain, PW8 portrayed that the amino acid composition of toxin and DtxR in Malaysia's local strains are well-conserved and there was no functional defect noted. Hence, the change in efficacy of the currently used toxoid vaccine is unlikely to occur.

Topics: Corynebacterium diphtheriae; Diphtheria; Diphtheria Toxoid; Genome, Bacterial; Humans; Malaysia; Phylogeny

In this study, we report the comparative genomics and phylogenetic analysis of Corynebacterium diphtheriae strain B-D-16-78 that was isolated from a clinical specimen in 2016. The complete genome of C. diphtheriae strain B-D-16-78 was sequenced using PacBio Single Molecule, Real-Time sequencing technology and consists of a 2,474,151-bp circular chromosome with an average GC content of 53.56%. The core genome of C. diphtheriae was also deduced from a total of 74 strains with complete or draft genome sequences and the core genome-based phylogenetic analysis revealed close genetic relationship among strains that shared the same MLST allelic profile. In the context of CRISPR-Cas system, which confers adaptive immunity against re-invading DNA, 73 out of 86 spacer sequences were found to be unique to Malaysian strains which harboured only type-II-C and/or type-I-E-a systems. A total of 48 tox genes which code for the diphtheria toxin were retrieved from the 74 genomes and with the exception of one truncated gene, only nucleotide substitutions were detected when compared to the tox gene sequence of PW8. More than half were synonymous substitution and only two were nonsynonymous substitutions whereby H24Y was predicted to have a damaging effect on the protein function whilst T262V was predicted to be tolerated. Both toxigenic and non-toxigenic toxin-gene bearing strains have been isolated in Malaysia but the repeated isolation of toxigenic strains with the same MLST profile suggests the possibility of some of these strains may be circulating in the population. Hence, efforts to increase herd immunity should be continued and supported by an effective monitoring and surveillance system to track, manage and control outbreak of cases.

Topics: Computational Biology; Corynebacterium diphtheriae; CRISPR-Cas Systems; Diphtheria; Diphtheria Toxin; Genome, Bacterial; Genomics; Humans; Malaysia; Molecular Sequence Annotation; Phylogeny; Whole Genome Sequencing

A throat swab from a 9 year old girl with pharyngitis yielded a non-toxigenic strain of Corynebacterium diphtheriae var mitis and Streptococcus group G. C pseudodiphtheriticum was isolated from the throats of two of her four brothers. In each case the isolate was sent to the reference laboratory before full identification. The growth was found to be mixed for one brother; the other isolate being a toxin producing C diphtheriae var gravis. The child was asymptomatic and the case proves that all colonial types on the Hoyles plate should be identified.

Topics: Child; Child, Preschool; Corynebacterium; Corynebacterium diphtheriae; Diphtheria; Disease Outbreaks; Family Health; Female; Humans; Infant; London; Malaysia; Male; Pharyngitis; Species Specificity; Streptococcus

Topics: Adult; Child; Diphtheria; Diphtheria Toxoid; Humans; Immunization; Incidence; Malaysia; National Health Programs

A review of patients with diphtheria seen in the Paediatric Unit, Alor Star General Hospital, from January 1985-March 1987 is reported. Their clinical presentation, diagnosis, treatment and outcome were analysed and discussed. Clinical awareness regarding the diagnosis of diphtheria is emphasised.

Topics: Child, Preschool; Corynebacterium diphtheriae; Diphtheria; Female; Humans; Infant; Malaysia; Male; Penicillins

In Malysia, the proportion of children fully immunized againest diphtheria is generally low (20%). On the other hand, the Schick conversion rate rises with age and reaches 90% by 11 years of age. It is noted that asymptomatic carriers are an important epidemiological factor in diphtheria and that carrier rates for school children are high (prevalence of 7.5% while the rate of coloization with C. diphtheriae over a period of one year was 30%). Although immunization protects against clinical diphtheria, it does not prevent the carrier state. Thus, for the control of diphtheria, one should aim for 100% compliance. Some suggestions as to how higher levels of immunity may be achieved are described.

Topics: Carrier State; Child; Diphtheria; Female; Humans; Malaysia; Male

Topics: Child Health Services; Diphtheria; Humans; Immunization Schedule; Infant; Malaysia; Patient Dropouts; Preventive Health Services; Smallpox Vaccine

Topics: BCG Vaccine; Child; China; Dental Caries; Diphtheria; Ethnicity; Feces; Female; Humans; Immunization; India; Lice Infestations; Malaysia; Male; Morbidity; Nematoda; Poliomyelitis; Scabies; School Health Services; Smallpox; Socioeconomic Factors; Tetanus; Vitamin A Deficiency; Whooping Cough

Topics: Adolescent; Age Factors; BCG Vaccine; Child; Child, Preschool; Diphtheria; Diphtheria Toxoid; Humans; Immunization Schedule; Infant; Infant, Newborn; Malaysia; Smallpox; Smallpox Vaccine; Vaccination

Topics: BCG Vaccine; Child Health Services; Child, Preschool; Diphtheria; Humans; Immunization; Immunization Schedule; Infant; Infant, Newborn; Malaysia; Methods; Models, Theoretical; Tetanus