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Introduction: Group G streptococcus (GGS) accounted for 8% to 44% of all bacteraemias due to beta-haemolytic streptococci according to various reports. The aims of this study were 1) to describe the epidemiology of GGS bacteraemia in Singapore for which local data are lacking and 2) to compare its frequency of isolation to the other Lancefield groups., Patients and Methods: The study period was from 1 January 1996 to 30 June 1998. The laboratory records of 2 large acute care hospitals were examined. There was a total of 85 patients. The medical records of 52 patients were available for analysis. In addition, laboratory microbiological data from 1993 to 1999 were reviewed and the number of blood cultures that were positive for beta-haemolytic streptococci groups A, B, C and G was collated., Results: The majority involved the elderly. The mean age was 67 years. The skin was the major portal of entry. Local conditions predisposing the skin to infection occurred in 40.4%. Co-morbidity included malignancies in 28.8% of patients, diabetes mellitus in 11.5% and liver disease in 9.6%. Mortality was 15.4% including fatal septic shock. Recurrent bacteraemia occurred in 5.8% of the patients. The majority (90.4%) were community-acquired infections. GGS, along with group B streptococcus (GBS), was the most common streptococcus among the beta-haemolytic streptococci causing bacteraemia in these 2 hospitals.

There are two major advances in the laboratory diagnosis of Chlamydia trachomatis, one lies in the use of nucleic acid amplification techniques and the second in the evaluation of urine as an alternative to invasive sampling of urethral and cervical specimens. There is however, the problem of inhibitors in urine that needs to be addressed, in order for this method to achieve 100% sensitivity. The Q-beta (Q beta) replicase test, Gen-Probe transcription-mediated amplification (TMA) test and the nucleic acid sequence-based amplification (NASBA) test are some of the newer nucleic acid amplification methods being evaluated for the detection of C. trachomatis. These are RNA-based amplification techniques that can potentially achieve very high levels of sensitivity because of the presence of multiple RNA copies in microorganisms and may also be useful for detecting active infection. Q-beta has been found to be less subjected to inhibitory substances in urine than polymerase chain reaction (PCR). Cell culture remains the gold standard for the legal diagnosis of C. trachomatis infections and is the method of choice for the detection of infection at uncommon sites. It forms part of the expanded gold standard for the evaluation of nonculture methods that do not involve nucleic acid amplification, and is also a confirmatory test for such techniques. Notwithstanding, clinicians must remember the basic tenet of laboratory tests, that is, good specimen collection and handling, for any laboratory test to yield accurate information to guide their management of patients.

A large outbreak of food poisoning occurred in September 1996 and involved at least 116 workers at a shipyard in Jurong. Salmonella weltevreden was isolated from the stool specimens of 24 hospitalised cases and three food handlers, giving a total of 27 bacteriologically confirmed cases (25 symptomatic and two asymptomatic) in this outbreak. Based on a case-control analysis, a number of food items consumed on 23 and 24 September 1996 were implicated in the outbreak, viz. a vegetable dish (P < 0.01), watermelon juice (P < 0.01) and cut watermelon (P < 0.001), papaya (P < 0.001) and pineapple (P < 0.05). The median incubation period was 38 hours and the median duration of illness was two days. Four samples of cut fruits obtained from a food stall at the canteen were found to be positive for Salmonella weltevreden. (The antibiogram of all the strains isolated from food samples and stool cultures was similar, consistent with a common source of infection.) Extensive investigation suggested that contamination may have occurred through unauthorised use of industrial water for washing the fresh produce. Early recognition of the outbreak and prompt implementation of control measures prevented further spread of infection.