For the first time since national reporting began in 2021, respiratory syncytial virus (RSV) has overtaken influenza as Australia’s most common respiratory virus this winter, with more than 83,000 cases recorded nationwide and nearly 900 new infections detected daily. The shift has prompted health authorities to renew calls for older Australians to receive a free RSV vaccine that became available two months ago, yet uptake remains far behind influenza immunisation: over 1.76 million eligible people have received a flu shot this year, compared with just 722,530 RSV doses administered. In Western Australia, where 5,044 RSV cases have been logged, the state’s medical association warns the virus can lead to pneumonia and hospitalisation in vulnerable populations.

Brazilian regulators have approved a new trivalent influenza vaccine, Fluprevli, for use in people aged six months and older. Clinical trials demonstrated efficacy of up to 73 per cent in adults and 65 per cent in children, with the inactivated vaccine targeting influenza A and B strains. The formulation follows international guidance to remove the B/Yamagata lineage, which has not been detected globally since March 2020. Before the vaccine can be distributed through the public health system, it must be evaluated by the national technology incorporation commission (Conitec) and approved by the Ministry of Health; no timeline has been set for that process.

Argentina’s epidemiological bulletin for week 26 shows influenza A(H3N2) remains the dominant respiratory virus, though RSV is registering a slight increase, with 22 cases in the past four weeks and 85 among hospitalised patients. SARS-CoV-2 circulation is stable and low. The same bulletin reports a continued decline in chikungunya fever, with only three of 13 new cases linked to the most recent epidemiological week, bringing the season total to 2,832, concentrated in the northwest. Dengue activity remains subdued, with no new confirmed cases and a drop in suspected notifications.

In São Paulo state, seven measles cases this year have prompted health authorities to recommend a “dose zero” of the MMR vaccine for infants aged six to eleven months in the capital and Guarulhos, alongside a vaccination drive at commuter rail stations. Meanwhile, Bangladesh’s health directorate will introduce the typhoid conjugate vaccine into its routine immunisation programme from 1 August, offering a single dose to all 15-month-old children alongside the second measles-rubella shot. The next milestones to watch are the Conitec review in Brazil, the 1 August rollout in Bangladesh, and Australia’s winter surveillance data as RSV season progresses.