There are currently around 200 SARS-CoV-2 candidate vaccines in preclinical and clinical trials throughout the world. The various candidates employ a range of vaccine strategies including some novel approaches. Currently, the goal is to prove that they are safe and immunogenic in humans (phase 1/2 studies) with several now advancing into phase 2 and 3 trials to demonstrate efficacy and gather comprehensive data on safety. It is highly likely that many vaccines will be shown to stimulate antibody and T cell responses in healthy individuals and have an acceptable safety profile, but the key will be to confirm that they protect against COVID-19. There is much hope that SARS-CoV-2 vaccines will be rolled out to the entire world to contain the pandemic and avert its most damaging impacts. However, in all likelihood this will initially require a targeted approach toward key vulnerable groups. Collaborative efforts are underway to ensure manufacturing can occur at the unprecedented scale and speed required to immunize billions of people. Ensuring deployment also occurs equitably across the globe will be critical. Careful evaluation and ongoing surveillance for safety will be required to address theoretical concerns regarding immune enhancement seen in previous contexts. Herein, we review the current knowledge about the immune response to this novel virus as it pertains to the design of effective and safe SARS-CoV-2 vaccines and the range of novel and established approaches to vaccine development being taken. We provide details of some of the frontrunner vaccines and discuss potential issues including adverse effects, scale-up and delivery.

Non-typhoidal Salmonellae are a major cause of infectious diarrhoea worldwide and can cause invasive diseases, including bacteraemia, meningitis and osteomyelitis. Young or immunocompromised children and those with underlying conditions such as sickle cell disease are particularly vulnerable to invasive disease. There has been an increase in the rate of resistant non-typhoidal Salmonella, which is associated with invasive disease and hospitalisation. The intracellular nature of non-typhoidal Salmonella protects against extracellular antibiotics and can facilitate disease relapse, particularly meningitis. Effective antimicrobial agents with good intracellular penetration include azithromycin, fluoroquinolones and third-generation cephalosporins. Antibiotic treatment of non-typhoidal Salmonella gastroenteritis is only indicated if there are risk factors for invasive disease as it can prolong excretion and does not shorten the duration of gastrointestinal symptoms. Optimal choice and length of therapy for gastroenteritis and invasive disease in children is not clear. Here, we provide a review of the literature and treatment recommendations.

People with asplenia/hyposplenism are at increased risk of fulminant sepsis, which carries a high mortality rate. A range of preventive measures is recommended although there is ongoing evidence that knowledge of and adherence to these strategies is poor. There have been significant changes in recommended vaccinations since the previously published recommendations in 2008. We provide current recommendations to help Australian and New Zealand clinicians in the prevention of sepsis in patients with asplenia and hyposplenia. The guideline includes Australian epidemiological data, preferred diagnostic techniques and recommendations for optimal antimicrobial prophylaxis and vaccination protocols.

Hand-foot-and-mouth disease is a common, usually mild childhood illness caused by enteroviruses. Over the last five years, coxsackievirus A6 has been identified as a causative agent in outbreaks in Europe, South-East Asia and America. It has an atypical presentation compared with other enteroviruses, with more widespread rash, larger blisters and subsequent skin peeling and/or nail shedding. We give the first description of an outbreak of coxsackievirus A6 in New Zealand and how health-care communication networks enabled detection of and dissemination of information about this emergent strain.

Childhood empyema incidence has increased markedly in South Auckland. Paediatric S. aureus empyema is becoming increasingly common in South Auckland. Pre-hospital antibiotic prescribing may mitigate the need for surgical intervention in our population.

The incidence of NTM infection in Australian children is 0.84 of 100,000 (95% CI: 0.68-1.02). Infection occurs most often in young children without predisposing conditions. Despite therapy, there was recurrence in 23.4% of cases.

Current evidence suggests that endocarditis of either native or prosthetic valves, caused by penicillin-susceptible C. diphtheriae, demonstrates a favorable outcome when treated with either a β-lactam alone or in combination with an aminoglycoside. Patient-specific factors will determine which approach is more appropriate for each individual patient.

Globally, autosomal recessive IFNAR1 deficiency is a rare inborn error of immunity underlying susceptibility to live attenuated vaccine and wild-type viruses. We report seven children from five unrelated kindreds of western Polynesian ancestry who suffered from severe viral diseases. All the patients are homozygous for the same nonsense IFNAR1 variant (p.Glu386*). This allele encodes a truncated protein that is absent from the cell surface and is loss-of-function. The fibroblasts of the patients do not respond to type I IFNs (IFN-α2, IFN-ω, or IFN-β). Remarkably, this IFNAR1 variant has a minor allele frequency >1% in Samoa and is also observed in the Cook, Society, Marquesas, and Austral islands, as well as Fiji, whereas it is extremely rare or absent in the other populations tested, including those of the Pacific region. Inherited IFNAR1 deficiency should be considered in individuals of Polynesian ancestry with severe viral illnesses.