METHODS: This retrospective observational study included 185 families of paediatric COVID-19 cases from 1 February 2020 to 31 December 2020. We identified the index case for each household and gathered the socio-demographic, epidemiological investigation results and risk factors for household transmission from medical case records. The secondary attack rate was calculated, and logistic regression analyses were used to identify risk factors associated with secondary household transmission of SARS-CoV-2.

RESULTS: Of the 848 household contacts, 466 acquired secondary infections, resulting in a secondary attack rate of 55%. The median age of the secondary cases was 12 years. Female household contacts and household contacts who slept in the same room with the index case were significantly associated with increased risk for COVID-19. Other independent risk factors associated with higher transmission risk in the household included an index case who was symptomatic, a household index case aged greater than 18 years and a male household index case.

MATERIALS AND METHODS: This retrospective cross-sectional study involved record review of all blood culture results over 9 months period from 1st January 2018 until 30th September 2018 in 27 government hospitals in Malaysia. For each positive culture result, the type of isolated organism was classified to represent true bacteraemia or contamination.

RESULTS: We analysed 448,109 blood culture records from the participating hospitals. The blood culture positivity rate was 12.5% (57395 of 448109) and 25.0% (14367 of 57395) of the positive blood culture represents contamination. The national blood culture contamination rate in Malaysia was 3.2%. The contamination rate in the adult population was significantly higher than the paediatric population (3.6% vs. 2.6%; p<0.001). The blood contamination rate by institution ranged from 1.5% to 6.8%. The most frequently isolated microorganisms in the contaminated cultures were coagulase-negative staphylococci (71.0%).