INTRODUCTION Methicillin-resistant Staphylococcus aureus (MRSA) is an established nosocomial pathogen that causes infections, such as bacteremia, respiratory tract infections, skin and soft tissue infections (SSTIs), bone and joint infections, and urinary tract infections (1, 2). The prevalence rate of hospital-acquired MRSA infections was the highest (＞50) in Asia, South America, and Malta, followed by lower prevalence rates (25-50) in Australia, China, Africa, Romania, Greece, Italy, and Portugal (3). The prevalence rate of MRSA in Malaysia has been reported to increase from 17 in 1986 (4) to 44 in 2007 (5). To date, healthcare-associated MRSA (HA-MRSA) remains a global healthcare concern; however, the emergence of community-associated MRSA (CA-MRSA) since the 1990s poses significant risks and threats to both hospital and community populations. The current modality of treatment for MRSA infections is prescribing antibiotics, such as vancomycin, linezolid, rifampicin, and fusidic acid (2,6). The molecular epidemiology of MRSA can be studied using different typing methods, such as staphylococcal cassette chromosomal mec (SCCmec) typing, multilocus sequence typing (MLST), and pulsed

Concurrent bacteraemia in patients with dengue fever is rarely reported. We report a case of a patient who initially presented with symptoms typical of dengue fever but later succumbed to septic shock caused by hypervirulent methicillin-susceptible Staphylococcus aureus (MSSA). A 50-year-old female patient with hypertension and diabetes mellitus presented with typical symptoms of dengue fever. Upon investigation, the patient reported having prolonged fever for four days prior to hospitalization. Within 24 hours post-admission, the patient developed pneumonia and refractory shock, and ultimately succumbed to multiple-organs failure. Microbiological examination of the blood culture retrieved a pan susceptible MSSA strain. Genomic sequence analyses of the MSSA strain identified genes encoding staphylococcal superantigens (enterotoxin staphylococcal enterotoxin C 3 (SEC3) and enterotoxin-like staphylococcal enterotoxins-like toxin L (SElL)) that have been associated with toxic shock syndrome in human hosts. Genes encoding important toxins (Panton-Valentine leukocidins, alpha-haemolysin, protein A) involved in the development of staphylococcal pneumonia were also present in the MSSA genome. Staphylococcus aureus co-infections in dengue are uncommon but could be exceptionally fatal if caused by a toxin-producing strain. Clinicians should be aware of the risks and signs of sepsis in dengue fever, thus allowing early diagnosis and starting of antibiotic treatment in time to lower the mortality and morbidity rates.

Staphylococcus aureus (S. aureus) is an opportunistic pathogen capable of causing serious health implications in susceptible individuals once it invades the host’s protective barriers. Methicillin-susceptible S. aureus (MSSA) often receives lesser attention although it has been frequently associated with serious infections in human. We aim to investigate the genomic features of a highly virulent yet pan susceptible MSSA strain (coded as HS-MSSA) which caused concurrent bacteraemia in a dengue patient, ultimately resulted in sepsis death of the patient. Whole genome sequence analysis was performed. The draft genome of HS-MSSA is approximately 2.78 Mb (GC content = 32.7%) comprising of 2637 predicted coding sequences. In silico genotyping of the HS-MSSA strain revealed a novel combined genotype (t091/ST2990). The HS-MSSA carries a SaPIn1-like pathogenicity island that harbours the staphylococcal enterotoxin and enterotoxin-like genes (sec3 and selL). The strain-specific β-lactamase (blaZ)-bearing plasmid region was identified in HS-MSSA. Core genome phylogeny showed that the HS-MSSA strain shared a common ancestry with the European MRSA clone. We report herein the genomic features of an MSSA lineage with novel genotype previously not reported elsewhere.