Sir Arnold Theiler was instrumental in developing a vaccine that curbed the epizootic. Vaccination of poultry against the H5N1 epizootic is widespread in certain countries. Experiments started in Mecklenburg during the epizootic of the late 1770s. She ran a committee to combat epizootic diseases. Aeromonas caviae is a Gram-negative bacterium of the genus "Aeromonas" isolated from epizootic guinea pigs. By June 2015, no definitive cause for the epizootic had been found. Cases of rabies in this species are generally epizootic and recurrent. It is responsible for epizootic outbreaks that have led to the collapse of aquaculture operations. At unpredictable times it becomes epizootic in unexpected places. The results indicated that an epizootic dengue virus was active among the macaques. In recent years populations have also declined with an epizootic "Ranavirus" infection. It is during these epizootic outbreaks that transmission to humans is most common. Epizootic hemorrhagic disease (EHD) has been around for many years. Dermo epizootic outbreaks occurred in the Gulf of Mexico in the 1940s. The causes of these stranding have been changing from epizootic to enzootic.