Kampala, Uganda (CNN) -- More than 90 animals in Uganda have died since June from a vicious strain of anthrax, officials said Thursday.
Those killed include 82 hippopotamuses and nine buffalo. The areas most affected surround the Kazinga Channel, a tourist attraction linking Lake Edward and Lake George in the Queen Elizabeth National Park near Uganda's western border with the Democratic Republic of Congo.
The strain remains limited to the Kazinga channel, Nicholas K. Kauta, commissioner of the Ministry of Agriculture, Animal Industry and Fisheries and head of an anthrax task force, told reporters. The animals died after drinking water from the channel, he said.
The outbreak was first suspected in June, when more than a dozen hippos died from a disease with symptoms resembling those of anthrax. Samples were taken for testing, Kauta said, and lab tests confirmed the presence of the disease.
"Hippos remain the most affected animals since Uganda first suffered this strain, in the 1950s," said Moses Mapesa, executive director of the Uganda Wildlife Authority. The strain thrives in water, he said.
A 2004 outbreak of anthrax killed more than 300 hippos and scores of other wildlife, including lions and scavenger birds.
Mapesa said there was no evidence the disease has spread to Uganda's neighbors, the Democratic Republic of Congo and Rwanda.
There was also no confirmation of any human infections. Authorities would not confirm reports that five people had died after eating meat of animals who died from anthrax.
"We have no evidence yet," Kauta said. "We have heard such reports, but the affected families in communities living near the now-endangered area (are) concealing information by not reporting to health authorities for fear of being arrested for poaching."
The task force will not arrest any victims who are sickened from eating meat from animal carcasses, he said.
"We know hippo and buffalo meat is very attractive, and many people when they find these animals dead, they just devour on the carcass, something which is dangerous because they would be eating contaminated meat," he said.
Officials discourage eating game meat from the affected area, he said, especially animals found dead, he said. Even if anthrax is not present, the animals could have been poisoned by poachers.
Livestock in the area are being vaccinated, and health officials in surrounding districts are on high alert.
In humans, anthrax manifests itself in three forms and can affect the skin, stomach, intestines and lungs, Kauta said. With proper medical treatment "deaths from this type of anthrax are rare," he said.