Strongyloides stercoralis is an intestinal nematode capable of infecting humans and dogs. Occurrence in dogs from temperate, traditionally non-endemic regions remains poorly characterized, often due to the absence of accessible veterinary diagnostic tests. Recent reports of infections from temperate metropolitan areas have raised concerns about the extent of S. stercoralis prevalence in dogs in these regions. This study investigated the presence of S. stercoralis DNA in canine faecal samples from Sydney, New South Wales, Australia, using a real-time quantitative PCR (qPCR) targeting the 18S rRNA gene, with a limit of detection of 2 DNA copies. Archived faecal DNA (n = 448) collected between 2014 and 2024 from 2 university veterinary hospitals were screened. Of all samples, 1 (0.02%) was positive for S. stercoralis DNA, corresponding to approximately 6.8 × 103 18S rDNA copies, equivalent to 3.2 of S. ratti third-stage larvae, per 250 mg of dog faeces. Partial cox1 and 18S rDNA loci (HVR-I and HVR-IV) deep amplicon sequencing confirmed that S. stercoralis circulates between dogs and humans. The positive sample originated from a Border Collie puppy presenting with gastrointestinal signs. Although detection was rare, this confirms the parasite’s presence in companion dogs within a temperate urban environment. The results highlight the diagnostic utility of 18S rDNA-based qPCR for retrospective surveillance and support the inclusion of S. stercoralis in molecular diagnostic panels for dogs with gastrointestinal disease. Expanded, targeted molecular and coproscopic surveillance is warranted to clarify the prevalence, distribution and zoonotic potential of S. stercoralis in dogs across Australia’s non-endemic regions.

Japan experienced dengue outbreaks vectored by Aedes albopictus during the Second World War. The probable vector density that caused the largest dengue outbreak in Nagasaki in 1942 was estimated using a mathematical simulation model. The estimated vector density was 15·0–558·0 per person when various assumptions of uncertain parameters were applied, such as proportion of symptomatic cases, vector mortality, and human biting rate of A. albopictus. When the most favourable disease spread conditions, such as a combination of the exclusive human biting rate and the longest vector survival were assumed, the vector density was 15–25 mosquitoes per person. Unusually high vector density due to wartime practices, and the traditional Japanese lifestyle were presumably responsible for the earlier dengue outbreak. If an outbreak occurs in present-day Japan, it is unlikely to spread as much as the previous one, as environmental conditions and human behaviour have changed in a protective manner.

The rates of water loss and humidity preference of carabids from dry tropical habitats have been studied and compared with corresponding data from temperate carabids and tropical tenebrionids. Within each group of beetles the rate of relative water loss decreases with increasing body size. Carabids from dry tropical areas have rates of water loss which are lower than those of temperate species, but considerably higher than the values for tenebrionids from dry tropical habitats. Small temperate carabids can stay in dry air for only a few hours, whereas large tropical tenebrionids may survive for weeks without becoming critically dehydrated. Given the choice between a dry and a humid atmosphere, well hydrated beetles of all groups will initially choose the dry atmosphere. Most temperate carabids will switch to humid atmosphere after a few hours and tropical carabids after 1–3 days, whereas tropical tenebrionids may remain in dry air for almost 3 weeks. The temperate carabids are very sensitive to dehydration and will shift to a humid atmosphere when dehydrated by only 2–5%. Tropical carabids and tenebrionids will shift first when they are dehydrated by 7–20% of their body weight in a hydrated state, implying that these beetles are considerably less sensitive to water loss than temperate carabids.