She said the locusts did not cause much damage since most had died following the spraying while the rest of the swarms were immobile due to the effects of the pesticide.
“We are still doing aerial and ground surveillance but the swarms that were in Meru have been contained,” Ms Mutiga said.
By Sunday afternoon, the locust swarms had invaded Mariara, Kipsing and Sereolipi in Meru, Isiolo and Samburu counties respectively where spraying was ongoing.
Sources close to the operation said that aerial spraying that was scheduled to go on for three days was interrupted on Monday morning due to rains and cloudy weather.
Meru, Tharaka-Nithi, Isiolo, Laikipia and Samburu counties, with the support of the Northern Rangeland Trust, Lewa Conservancy and private firms from the region, have formed a joint team to fight the desert locusts.
Dr Muo Kasina, the chairman of the Entomological Society of Kenya, said they are yet to establish the economic damage caused by the desert locusts in the affected areas.