On March 17, 2003 the Kelantan Health Department was notihed about a possible typhoid outbreak following a wedding party. An investigation was carried out to identiy the source and recommend control measures. Active case detection, yield investigation and case»control study were conducted. Cases were symptomatic attendees with a stool or blood culture positive for Salmonella
typhii. Each control had a negative culture and denied symptoms. Of the more than 1 OOO guests, 477 experienced fever; 152 met the case definition. The party hostess was found to be an Salmonelb typhii carrier. Syrup prepared with untreated well water was identified as the most likely source for this outbreak, with an odds ratio 14.0 (95% C1: 2.9, 104.1). This was a common source
outbreak of typhoid. We recommend that all food handlers at large parties be screened for typhoid and other foodborne diseases and samples of higherisk foods should be kept for few days after each event in case they are needed for testing.
Past major flooding events for the state of Johore, Malaysia were recorded in 1926, 1967, 1968 and 1971. However, major meteorological phenomena that hit Johore on the 19th December 2006 (first wave) and the 12th January 2007 (second wave) were claimed to be the worst flood disaster in Johore in a 100 years. All eight districts were affected displacing 157,018 and 155,368 population during the first and the second wave event respectively. The Johore Health Department deployed substantial number of medical and health personnel to deal with the Johore flood crisis. Flood-related data were collected on daily basis between 19th December 2006 and 19th February 2007 using spreadsheet format from Flood Operational Rooms located at respective District Health Offices. Among flood victims 34,530 were found to have non-communicable diseases and 19,670 with communicable diseases. No major food- and water-borne disease outbreaks, such as cholera and typhoid, were reported in Johore. High success of public health measures was depending on the workforce of medical and health personnel on the ground. On the other hand, voluntary services offered by non-governmental organisations (NGOs), private sector and other volunteers should be well coordinated without compromising regulatory and ethical requirements. Crisis guidelines and plan of actions shall be updated so that they would be more relevant to the crises encountered on the ground.
The state of Johore, Malaysia had been hit by the worst flood in the Malaysian modern history on the 19th December 2006 (first wave) and the 12th January 2007 (second wave) affecting all the eight districts. A total number of 157,018 and 155,368 Johore population had been displaced by the first and the second wave event respectively. The Johore State Health Department activated the Flood Action Plan which include mobilising medical teams to conduct daily clinical examinations on the flood victims and health teams to inspect flood relief centres, food premises and homes at flood-hit areas with regard to prevent and control communicable diseases. The spreadsheet format was used to collect data on diseases, injury and death throughout the Johore flood disaster period starting from the 19th December 2006 until 19th February 2007. Analyses showed that 19,670 flood victims (36.3%) had communicable diseases and 34,530 (67.0%) had non-communicable diseases. As for the communicable diseases and symptoms/syndromes related to communicable disease, 41.3% were acute respiratory infections (ARI) followed by 25.9% skin infections, 19.1% fever, 10.1% acute gastroenteritis (AGE) and 3.0% acute conjunctivitis. Other infectious diseases include 61 notifiable diseases (46 food poisoning, 14 dengue fever and one tuberculosis), 20 leptospirosis (with two deaths), 20 chicken pox and two melioidosis cases. The Batu Pahat district had the highest incidence for the majority of the communicable diseases because of the prolonged flooding period. No cholera, typhoid, malaria, measles or hand-foot-mouth disease (HFMD) cases were detected among the Johore flood victims. Trends of disease incidence follow the number of evacuees placed in the relief centres corresponding to respective wave. A total of 507 flood victims had physical injuries related to flood mostly due to fall onto wet floor at the relief centres. Fifteen deaths due to drowning were mainly caused by accidental fall into the flood water. The incidence of communicable diseases encountered had been appropriately anticipated and managed attributed to enhanced public health control programmes augmented by syndromic and laboratory surveillance on potentialy fatal infectious diseases. Equal emphasis should be given to the surveillance and control of chronic diseases.
Background : Safe potable water is critical during and post flood. In the pre-flood period, Johore has an excellent, systematic and comprehensive water supply system. More than 98.6% of Johore population received treated water supply from the water treatment plants.
Methodology : Data collection was performed by conducting additional water sampling at routine sampling stations as well as the flood relief centres, water tankers (lorries) and static water tanks. Water treatment plant outlet and water tanker inlet shall have a minimum level of 2.0 mg/l of residual chlorine so that reticulation, water tanker outlets and static water tanks would have at least 0.5 mg/l as a measure to prevent the incidence of water borne diseases. Sampling was done everyday to monitor water quality at the flood relief centres as well as flood-hit areas. Inspections and surveillance on sanitation were also conducted on latrines, solid waste disposal systems and on the surrounding environment.
Results : A total of 6,283 water samples had been collected during and post flood. Violations on E. coli, turbidity and residual chlorine were 0.8%, 0.6% and 4.0% respectively with the Kluang district recorded the highest percentages for all the three parameters. A number of 621 wells had been inspected with 378 of them (60.9%) had been chlorinated. In order to ensure environmental cleanliness, 26,815 houses in 708 villages had been visited. Out of them, 2,011 houses (7.5%) were not satisfactory. Sanitation inspections found that 1,778 latrines, 2,719 domestic water sewerage systems and 2,955 solid waste disposal systems were under substandard conditions thus remedial actions had been taken immediately.
Conclusion : Although the flood disaster was massive with prolonged flooding period, however, an overall quality status on treated water supply was satisfactory whilst sanitary hygiene was under control. Hence, the incidence of communicable disease especially water borne diseases would not progress into serious outbreak, in fact, neither cholera nor typhoid was reported during the Johore flood disaster.
Background and Objective : Johor was affected by the worst flood in 100 years in December 2006 and again in January 2007. The concern that improper sanitary facilities and contaminated water supply at relief centres would result in contaminated food made monitoring of food hygiene vital. The objective of this paper is to describe food hygiene surveillance activities carried out in flood relief centres and flood affected areas and the challenges faced in carrying out these activities.
Methodology : The food hygiene surveillance activities were carried out by the Assistant Environmental Health Officers (AEHO) in the districts. Among the surveillance activities carried out are inspection of food preparation areas in relief centres, inspection of food premises in flood affected areas and food sampling. Premise inspections were carried out using a specific inspection format. Food samples taken were sent to Public Health Laboratory, Johor Bahru for microbiological analysis. Anti typhoid vaccination for food handlers were also carried out. Apart from that, observations made by the health teams were alsotaken into account.
Results : A total of 3,159 food preparation areas in relief centres were inspected. During the same period, a total of 2,317 food premises in flood affected areas were inspected as soon these premises started operating after the floods. Inspections showed that 69 food preparation areas in relief centres and 181 food premises in flood affected areas had unsatisfactory hygiene. A total of 1,566 holding samples were taken and 425 samples were sent to the laboratory for analysis. Forty-six of the samples analysed were found to be positive for pathogenic bacteria such as e. coli, staphylococcus aureus and salmonella.
Conclusion : The health personnel from the Johor Health Department in various districts carried out an excellent job in ensuring food safety during the floods. There were no outbreaks of food poisoning. However analysis of food samples taken during the floods did show the presence of pathogenic organisms but probably their numbers were not high enough to cause any food poisoning. The promotion and enforcement of food hygiene requirements should be carried out continuously to ensure that every individual understands the need for hygiene and food safety during disaster situation such as flood.
To find the incidence, markers and nature of complications of typhoid fever, we studied 102 children with cultures positive for Salmonella typhi in a cross-sectional study, prospectively, over a period of almost 5 years. All isolates were sensitive to commonly used antibiotics. One third of these children developed complications which included: anicteric hepatitis, bone marrow suppression, paralytic ileus, myocarditis, psychosis, cholecystitis, osteomyelitis, peritonitis, pneumonia, haemolysis, and syndrome of inappropriate release of antidiuretic hormone (SIADH). Twelve children developed multiple complications. If hepatitis is excluded from the complications, the rate of complications in bacteriologically confirmed cases of typhoid fever drops to 11 per cent. These complications were not related to: the age or sex of patients, duration of illness before admission, use of antibiotics before admission, nutritional status, level of 'O' or 'H' titre, presence of IgM or IgG antibodies, or treatment with chloramphenicol or ampicillin. Children with splenomegaly, thrombocytopenia or leukopenia were more likely to develop complications.
To investigate the role of serum C-reactive protein (CRP) in the diagnosis of typhoid fever, we studied 227 febrile Malaysian children hospitalized during a 12-month period. The children were: culture-positive for Salmonella typhi (Group 1; n = 108); culture-negative but with typical clinical features of typhoid fever (Group 2; n = 60); or had non-typhoidal illness (Group 3; n = 59). Group 1 children had the highest serum CRP concentrations (geometric mean [SD range]; 43 [12-150] mg/l vs. 26 [8-85] mg/l in Group 2 and 21 [4-110] mg/l in Group 3; p < 0.001). In regression analysis, age, patient group and fever duration were independently associated with serum CRP (p < 0.05) but gender was not. In Group 1 patients, there was a significant positive association between serum CRP and Widal O and H agglutinin titres. In receiver-operator characteristic (ROC) analysis of serum CRP for Groups 1 and 2 combined, compared with Group 3, the area under the curve (AUC) was 0.65. These data show that the serum CRP is highest in culture-positive children with enteric fever and reflects the immune response to the infection in this group. Nevertheless, serum CRP had relatively low sensitivity and specificity for confirmed or clinically diagnosed typhoid fever (68 and 58 per cent, respectively at 'cut-off' concentration 30.0 mg/l), and an AUC value only moderately above that associated with no predictive power (0.5). Although of limited use as a primary diagnostic test, a raised serum CRP may still have a place as one of a range of features that facilitate assessment of a febrile child in a typhoid-endemic area.
Data are presented for 2382 children investigated for fever in a Malaysian hospital between 1984 and 1987 when Widal tests and blood cultures were a routine part of every fever screen. There were 145 children who were culture positive (TYP-CP) for Salmonella typhi, while 166 were culture negative but were diagnosed as having typhoid (TYP-CN). Analyses of the sensitivity and specificity of combinations of initial Widal titres in predicting a positive S. typhi culture in a febrile child (culture positive vs the rest) showed the best model to be an O- and/or H-titre of > or = 1 in 40 (sensitivity 89%; specificity 89%). While the negative predictive value of the model was high (99.2%) the positive predictive value remained below 50% even for very high titres of O and H (> 1 in 640), at which point the specificity was 98.5%, supporting the clinical view that a high proportion of the TYP-CN patients really were typhoid but were missed by culture. The TYP-CN patients showed a very similar clinical and age profile to TYP-CP patients. The length of history of fever did not affect the initial Widal titre in culture positive cases. The Widal test in children remains a sensitive and specific 'fever screen' for typhoid although it will not identify all cases. In children, lower cut-off points for O- and H-titres should be used than are generally recommended.
With the development of de novo binders for protein targets from non-related scaffolds, many possibilities for therapeutics and diagnostics have been created. In this study, we described the use of de novo design approach to create single-chain fragment variable (scFv) for Salmonella enterica subspecies enterica serovar Typhi TolC protein. Typhoid fever is a global health concern in developing and underdeveloped countries. Rapid typhoid diagnostics will improve disease management and therapy. In this work, molecular dynamics simulation was first performed on a homology model of TolC protein in POPE membrane bilayer to obtain the central structure that was subsequently used as the target for scFv design. Potential hotspot residues capable of anchoring the binders to the target were identified by docking "disembodied" amino acid residues against TolC surface. Next, scFv scaffolds were selected from Protein Data Bank to harbor the computed hotspot residues. The hotspot residues were then incorporated into the scFv scaffold complementarity determining regions. The designs recapitulated binding energy, shape complementarity, and interface surface area of natural protein-antibody interfaces. This approach has yielded 5 designs with high binding affinity against TolC that may be beneficial for the future development of antigen-based detection agents for typhoid diagnostics.
A simple adherence test to detect IgM antibodies in patients with typhoid is described. The test utilises the IgM-"capture" approach, in which the test serum is applied to microtitration plate wells previously coated with anti-human IgM, followed by application of a stained Salmonella typhi antigen suspension which shows adherence in positive cases. By this test, 58 (95%) of 61 sera from confirmed cases of typhoid possessed IgM antibodies to the H or O or both antigens of S. typhi. In patients for whom a diagnosis of typhoid was based only on a significant Widal-test titre, 31 (41%) of 76 sera had IgM antibodies to the H or O or both antigens of S. typhi. Some cross-reactivity of the IgM antibodies was detected, especially with the O antigens of S. paratyphi A and B. A total of 82 sera from non-typhoidal fevers (leptospirosis, typhus, dengue fever) showed no reactivity in this test. In normal sera there was no detectable IgM to the O antigen of S. typhi and only a small number (3.9%) had low levels of IgM to the H antigen. The significance and potential importance of this simple, sensitive, specific and economical test is discussed.
Signal transduction through protein-protein interactions and protein modifications are the main mechanisms controlling many biological processes. Here we described the implementation of MedScan information extraction technology and Pathway Studio software (Ariadne Genomics Inc.) to create a Salmonella specific molecular interaction database. Using the database, we have constructed several signal transduction pathways in Salmonella enterica serovar Typhi which causes Typhoid Fever, a major health threat especially in developing countries. S. Typhi has several pathogenicity islands that control rapid switching between different phenotypes including adhesion and colonization, invasion, intracellular survival, proliferation, and biofilm formation in response to environmental changes. Understanding of the detailed mechanism for S. Typhi survival in host cells is necessary for development of efficient detection and treatment of this pathogen. The constructed pathways were validated using publically available gene expression microarray data for Salmonella.
The diagnostic value of the Widal test was assessed in an endemic area. The test was done on 300 normal individuals, 297 non-typhoidal fevers and 275 bacteriologically proven cases of typhoid. Of 300 normal individuals, 2% had an H agglutinin titre of 1/160 and 5% had an O agglutinin titre of 1/160. On the basis of these criteria a significant H and/or O agglutinin titre of 1/320 or more was observed in 93-97% of typhoid cases and in only 3% of patients with non-typhoidal fever. Of the sera from typhoid cases which gave a significant Widal reaction, the majority (79.9%) showed increases in both H and O agglutinins and 51 of 234 (21.8%) of these sera were collected in the first week of illness. The significance and implications of these findings are discussed.
Pulsed-field gel electrophoresis (PFGE) revealed that multiple genetic variants of Salmonella typhi are simultaneously present in Southeast Asia and are associated with sporadic cases of typhoid fever and occasional outbreaks. Comparative analysis of PFGE patterns also suggested that considerable genetic diversity exists among S. typhi strains and that some PFGE patterns are shared between isolates obtained from Malaysia, Indonesia, and Thailand, implying movement of these strains within these regions of Southeast Asia, where they are endemic.
Pulsed-field gel electrophoresis (PFGE) was used to compare and analyze 158 isolates of Salmonella typhi from five well-defined outbreaks of typhoid fever in Malaysia and also isolates involved in sporadic cases of typhoid fever occurring during the same period. Digestion of chromosomal DNAs from these S. typhi isolates with the restriction endonucleases XbaI (5'-TCTAGA-3'), SpeI (5'-ACTAGT-3'), and AvrII (5'-CCTAGG-3') and then PFGE produced restriction endonuclease analysis (REA) patterns consisting of 11 to 24 DNA fragments ranging in size from 20 to 630 kbp. Analysis of the REA patterns generated by PFGE after digestion with XbaI and SpeI indicated that the S. typhi isolates obtained from sporadic cases of infection were much more heterogeneous (at least 13 different REA patterns were detected; Dice coefficient, between 0.73 and 1.0) than those obtained during outbreaks of typhoid fever. The clonal nature and the close genetic identities of isolates from outbreaks in Alor Setar, Penang, Kota Kinabalu, Johor Bahru, and Kota Bahru were suggested by the fact that only a limited number of REA patterns, which mostly differed by only a single band, were detected (one to four patterns; Dice coefficient, between 0.82 and 1.0), although a different pattern was associated with each of these outbreaks. Comparison of REA patterns with ribotyping for 18 S. typhi isolates involved in sporadic cases of infection showed a good correlation, in that 72% of the isolates were in the same group. There was no clear correlation of phage types with a specific REA pattern. We conclude that PFGE of s. typhi chromosomal DNA digested with infrequently cutting restriction endonucleases is a useful method for comparing and differentiating S. typhi isolates for epidemiological purposes.