Fig. 4: Transmission of bovine H5N1 virus from lactating female mice to offspring.
From: Pathogenicity and transmissibility of bovine H5N1 influenza virus
Lactating female BALB/c mice (10–12 weeks old) were deeply anaesthetized, intranasally inoculated with 102 PFU of A/dairy cattle/New Mexico/A240920343-93/2024 (H5N1; ‘Cow-H5N1’) and then reunited with their suckling offspring (‘pups’). a–c, At day 4 (n = 5 biologically independent animals) (a), day 7 (n = 5 biologically independent animals) (b) or day 9 (n = 6 biologically independent animals) (c) postinfection, lactating females and their pups were euthanized and tissues were collected for plaque assays in MDCK cells. Milk was collected from five of six lactating females on day 9 postinfection only, as indicated, and tested by plaque assays in MDCK cells. In the figure, each box represents one cage with a lactating female and her pups. Animals for which Cow-H5N1 virus was detected in at least one tissue are coloured blue. At the lower left corner of each box, the status of each tissue or milk sample collected from the lactating females is indicated. Grey text indicates that no virus was detected, and red text indicates that virus was detected. Tissue abbreviations are: B, brain; MG, mammary gland; NT, nasal turbinate and L, lung. For the day 9 timepoint group, some of the lactating females succumbed to their infections before the designated endpoints, but within 12 h of tissue collection (indicated by asterisks). Tissues were collected from these mice and analysed along with the others. Created with BioRender.com.
