Fever is commonly used to diagnose disease and is consistently associated with increased mortality in critically ill patients. However, the molecular controls of elevated body temperature are poorly understood. We discovered that the expression of RNA-binding motif protein 3 (RBM3), known to respond to cold stress and to modulate microRNA (miRNA) expression, was reduced in 30 patients with fever, and in THP-1-derived macrophages maintained at a fever-like temperature (40°C). Notably, RBM3 expression is reduced during fever whether or not infection is demonstrable. Reduced RBM3 expression resulted in increased expression of RBM3-targeted temperature-sensitive miRNAs, we termed thermomiRs. ThermomiRs such as miR-142–5p and miR-143 in turn target endogenous pyrogens including IL-6, IL6ST, TLR2, PGE2 and TNF to complete a negative feedback mechanism, which may be crucial to prevent pathological hyperthermia. Using normal PBMCs that were exogenously exposed to fever-like temperature (40°C), we further demonstrate the trend by which decreased levels of RBM3 were associated with increased levels of miR-142–5p and miR-143 and vice versa over a 24 h time course. Collectively, our results indicate the existence of a negative feedback loop that regulates fever via reduced RBM3 levels and increased expression of miR-142–5p and miR-143.

The current public health emergency surrounding the COVID-19 pandemic, that is the illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in thousands of cases in Australia since 25 January 2020 when the first case was diagnosed. This emerging virus presents particular hazards to researchers and laboratory staff in a clinical setting, highlighted by rapid and widespread global transmission. Based on the epidemiological and clinical data that have become available in mid-2020, we propose the interim classification of SARS-CoV-2 as a Risk Group 3 organism is reasonable, and discuss establishing Biosafety Level 3 (BSL-3) regulations accordingly. Despite its global spread, the reported mortality rate of SARS-CoV-2 ranging from 0.13% to 6.22% is considerably less than that of other Risk Group 4 agents including Ebola and Marburg viruses with fatality rates as high as 90%. In addition, studies have demonstrated that approximately 86% of patients presenting with severe courses of the disease are aged 70 years or above, with the presence of comorbid conditions such as cardiovascular and respiratory system diseases in the majority of all fatal cases. In contrary to recent discussions surrounding the protective and administrative measures needed in a laboratory, the emerging evidence surrounding mortality rate, distinct demographics of severe infections, and the presence of underlying diseases does not justify the categorisation of SARS-CoV-2 as a Risk Group 4 organism. This article summarises biosafety precautions, control measures and appropriate physical containment facilities required to minimise the risk of laboratory-acquired infections with SARS-CoV-2.

One of the major characteristics of HIV-1 is its high genetic variability and extensive heterogeneity. This characteristic is due to its molecular traits, which in turn allows it to vary, recombine, and diversify at a high frequency. As such, it generates complex molecular forms, termed recombinants, which evade the human immune system and so survive. There is no sequence constraint to the recombination pattern as it appears to occur at inter-group (between groups M and O), as well as interand intra-subtype within group M. Rapid emergence and active global transmission of HIV-1 recombinants, known as circulating recombinant forms (CRFs) and unique recombinant forms (URFs), requires urgent attention. To date, 55 CRFs have been reported around the world. The first CRF01_AE originated from Central Africa but spread widely in Asia. The most recent CRF; CRF55_01B is a recombinant form of CRF01_AE and subtype B, although its origin is yet to be publicly disclosed. HIV-1 recombination is an ongoing event and plays an indispensable role in HIV epidemics in different regions. Africa, Asia and South America are identified as recombination hot-spots. They are affected by continual emergence and cocirculation of newly emerging CRFs and URFs, which are now responsible for almost 20% of HIV-1 infections worldwide. Better understanding of recombinants is necessary to determine their biological and molecular attributes.