As the annual gnu migration from Tanzania’s Serengeti Park into Masai Mara Game Reserve gathers momentum, herders have begun counting losses as virus spreads from wildlife to cattle
Alex Lekishon and Peter Leshan @PeopleDailyKe
Thousands of livestock in Masai Mara might be wiped out following an outbreak of the Wildebeest-associated malignant catarrhal fever. The disease has been reported in Aitong, Ngosuani and Talek areas by cattle keepers.
Residents claimed that they have already lost some of their livestock to the disease the Maasai call emoyian oo ingati (disease of the wildbeest), and accused the Narok County Veterinary Department of failing to act to curb further losses.
Notwithstanding the beauty and interesting sceneries of the annual trek in the Maasai Mara that attract hundreds of local and international tourists to the reserve, pastoralists are not happy with the migration.
Hundreds of cattle are said to have died due to the disease associated with the wildebeests. “The department has failed in its duty to provide solutions to forestall impending deaths. The disease is spreading, killing cattle fast and it is time to act,” decried James Yiale, a pastoralist from Ngosuani area.
However, the Committee Executive Officer in Charge of Agriculture and Livestock in Narok county, Evelyn Koyian said the county government’s Department of Livestock is working on deploying a contingent of veterinary officers to assess the situation and come up with a long lasting solution.
“The county veterinary officers will be doing a vaccination in the whole of Masai Mara regions starting from this week,” said Koyian.
According to Dr Patrick Bongon, a veterinary officer based in the Masai Mara, the disease is known as wildebeest-associated malignant catarrhal fever, which is an acute disease of cattle caused by alcelaphine virus.
“This infection has been a significant constraint to cattle production in nomadic pastoralist systems in Masai Mara Game Reserve. The transmission of the disease is dependent on the presence of the wildlife reservoir and birthplace of wildebeests,” said Bongon.
He said in Eastern Africa, the disease is commonly referred to by pastoralists as ugonjwa wa nyumbu, a Kiswahili term directly translated to mean “disease of the gnu or wildebeest. “It is a dangerous cattle disease with the highest perceived impact on cattle production and livelihoods of pastoralist communities,” he added.
The annual outbreaks of the disease occur in the wildebeest zones in Kenya and Tanzania, coinciding with the wildebeest calving season. Peak transmission is reported between February and April in Tanzania, varying slightly to July and August in Kenya’s Masai Mara every year.
Dr Bongon said the disease kills more than 1,000 cattle each year in the areas surrounding the Masai Mara region. Transmission of the malignant fever to cattle occurs when they come into close contact with wildebeest calves when the young beasts are shedding cell-free viruses in their ocular and nasal secretions. The respiratory tract is the natural route of infection.
There is no documented evidence of horizontal transfer of the virus from infected cattle to uninfected cattle. Hence, infected cattle are terminal or dead-end hosts of the disease.
However, vertical transmission of the virus also occurs in cattle, as in wildebeest, where the infected cow transmits the virus trans-placentally to her unborn foetus in the course of gestation.
Meanwhile, more than a million wildebeests are estimated to have finally crossed into Masai Mara National Reserve from Serengeti in Tanzania last week. Over 500,000 more are expected to cross by next weekend. Two million gnus are expected to have arrived by end of September, tour operators said.
The crossing, which this year delayed by about two months, started at Sand River, near the Mara Bridge and is still going on. The delay, the first since 1958 when Mara was established, was occasioned by prolonged rains in the Mara-Serengeti ecosystem that kept it green.
The trek, hoteliers and tour operators, say was further delayed by about three weeks because of burning of vegetation by Tanzania National Parks Authority (Tanapa) rangers in the northern Serengeti. The migrating gnus are using Sand River, which has now been reduced to a mere stream because of the fires along the usual Mara River crossing points.
“Whenever the first group enters the Mara, the rest follow. In less than a month about two million would have crossed,” said Ben Kipeno, a hotelier and the migration cycle expert.
Hoteliers say because of plenty of fodder and the delayed arrival to the Mara, unlike in the previous years, the gnus might stay in the reserve until mid October. “Because of the late crossing and burning of vegetation in Serengeti, which will take time to regenerate, they might stay long after calving,” says John Shongo, assistant manager Tipilikwani Camp.