Human contact with wildlife risky – scientists

Scientists have exposed great risks of emerging diseases from human and wildlife interactions especially in the highly degraded woodland areas.

Wednesday, July 02, 2008

Scientists have exposed great risks of emerging diseases from human and wildlife interactions especially in the highly degraded woodland areas.

According to Tony Mudakikwa, the Veterinary Officer of Rwanda Office of Tourism and National Parks (ORTPN), their close interactions pose hidden health threats to both sides.

Mudakikwa revealed on Monday that scabies, a skin infection associated with intense itching, cryptosporidium and giardia which cause diarrhoea, are some of the human transmitted parasitic diseases. 

"Some cases of scabies parasites were recently identified in Volcanoes National Park mountain gorillas,” he confirmed, adding that the three parasitic diseases are from domestic animals like cattle, cats and dogs.

Regarding diseases transmitted by primates, he singled out Ebola which struck and killed many people in eastern parts of the Democratic Republic of Congo (DRC) and western Uganda last year. 

"Wildlife and human disease transmission is now a worldwide concern,” said the ORTPN’s director of wildlife, Fidel Ruzigandekwe.

The concerns come in the wake of new study findings on potential human-primates parasitic transmission unveiled mid-June by Thomas R Gillespie, a US researcher.

Gillespie, a veterinary expert at the University of Illinois in the US, said in his report that the degraded forests in Uganda and the DRC have higher incidences of parasites transmission.

He indicated that these findings have implications on human health, in that some agents of these diseases dramatically increase the mortality of people suffering from HIV/AIDS.

His work analysed the abundance, variety and density of potentially harmful parasites in gorillas, chimps and monkeys living in Kibale and Bwindi in Uganda, and sites in the DRC.

Gillespie explained that he found a higher prevalence of infection among primates living in disturbed forest areas.

In logging areas in the DRC, the researcher reported the presence of strongyloides stercoralis, a parasitic roundworm that results in a hyper infection in HIV patients that carries a 98 percent mortality rate.

"The roundworm was likely introduced by loggers who defecate on the edges of logging sites,” Gillespie said.

"It is now abundantly clear that infectious diseases are a great threat to the survival of primate species.”

He noted that since primates are now picking up strongyloides stercoralis, it is possible that infected individuals could move into unspoiled forest areas, spreading the parasite to unaffected populations.

Gillespie’s research also indicated high antibiotic resistance among mountain gorillas visited by tourists in Uganda’s Bwindi Impenetrable National Park, while antibiotic resistance among unvisited gorillas was nearly zero; and that people are taking dramatic measures to reduce raiding by primates, including coating crops with cattle faeces.

The preventative measure opens up a new disease vector for the transmission between livestock, humans, and primates.

"Clearly this is bad for people and bad for primates,” he said, "The interface (between primates and humans) is growing as there is less forest habitat and more people.”

Gillespie said researchers have already detected the presence of cryptosporidium originally found only in livestock and wild monkeys and people near Kibale.

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