NYC health authorities reported an outbreak of 58 cases (2 deaths) with Legionnaires’ disease in Central Harlem from 25 July to 4 August. Specific cooling towers are probably the source of transmission, but investigations of clinical and environmental isolates (including whole genome sequencing) are still ongoing. People >50, smokers, with chronic lung disease and/or weakened immune system are at high risk.

Outbreaks linked to cooling towers have occurred in NYC in the past with the largest (138 cases) occurring between July and September 2015. A cooling tower is a specialized heat exchanger that removes heat from a system by circulating water and exposing it to the atmosphere, primarily through evaporative cooling. This cooled water is then recirculated back into the system, while the heat is dissipated into the atmosphere.

Italy has reported seven deaths from West Nile virus as of 29 Jul 2025 (all in individuals 65 and older and with underlying conditions), with outbreaks emerging in Lazio, Campania, and Piedmont, marking a shift from the traditionally affected northern regions. In response, health authorities have implemented mosquito control measures and restricted blood donations in 31 provinces.

More info on outbreaks among equids and birds in Europe is available in the ECDC and EFSA monthly report.

The World Health Organization warns of rapid spread of chikungunya from Indian Ocean islands into Africa, Asia and Europe that could soon affect billions of people. This follows the major surges of cases in La reunion, Mayotte and Mauritius earlier this year. WHO observes similar warning signs as in the last major outbreak 2 decades ago that affected half a million people worldwide.

The current epidemiological situation calls for increase disease surveillance and preparedness in regions where suitable vector of chikungunya is present.

A recent publication report that in 2024, a farmer was bitten by his cow after the animal itself has been bitten by a suspected rabid stray dog. The farmer who had prior rabies vaccination immediately received postexposure prophylaxis (booster). Three weeks later the cow showed abnormal behavior and died; laboratory tests confirmed rabies.

Rabies remains endemic in Pakistan, causing 2,000–5,000 deaths annually, mainly among children and rural populations. However, this annual death toll is variable due to the unavailability of reliable rabies data. More than 1.5 million dog bites happen each year in Pakistan, especially in cities like Karachi.

While dogs are the primary source of human rabies, this case demonstrates that livestock can also transmit the virus, particularly in areas with limited veterinary oversight. Rabies in cattle is underreported and more common than often thought. The incident underscores the importance of strong surveillance and improved access to vaccines for both humans and animals.

In 2025 and as of 16 July 2025, 4 locally transmitted cases have been reported from 3 European countries: Portugal (2), Italy (1), France (1).

In 2025 and as of 16 July 2025, 31 locally transmitted cases have been reported from France (30) and Italy (1). 

A 44-year-old man died of rabies 5 months after being bitten by a stray dog. He did not receive post-exposure prophylaxis. This is Romania’s first officially confirmed human rabies death since 2012.

With the arrival of the summer and increases in sea surface temperatures, the European Centre for Disease Prevention and Control (ECDC) is highlighting the seasonal risk posed by Vibrio bacteria.

The bacteria live naturally in brackish coastal waters, where saltwater and freshwater mix, especially when temperatures are high and salinity is lower.

Infections with Vibrio sp. are rare. If saltwater is swallowed or shellfish or mussels are eaten, the bacteria can be ingested and lead to gastroenteritis. If the bacteria enter the body through small skin lesions (e.g., injuries to coral or fish spines), there is a risk of fulminant sepsis, especially in immunocompromised individuals or those with chronic liver or kidney disease, diabetes, or iron storage disease. The bacterium is inactivated by cooking or freezing.

As of 9 June 2025, public health authorities in France have reported 25 cases of locally acquired chikungunya virus disease in 11 different local administrative units. All clusters are currently classified as active. The largest cluster consists of 10 cases and is located in Salon-de-Provence, Bouches-du-Rhône department.

This week authorities reported the first locally acquired chikungunya virus disease case from the Gironde department. In the previous week authorities reported the first locally acquired chikungunya virus disease case from the Bas-Rhin department. The other departments have reported locally acquired chikungunya virus disease or dengue cases in previous years.