Pakistan faces renewed waves of marauding locust swarms in the coming weeks, which could cause billions of dollars of crop losses as the country attempts to combat the Covid-19 pandemic. The world's sixth most populous nation has spent the past year battling its worst infestation in a quarter of a century. Perfect winter breeding conditions have meant more swarms now moving across the country and further waves are soon predicted to sweep in from neighbouring Iran, or the Horn of Africa. A double blow of crop losses coupled with the economic and health toll of the new coronavirus pandemic is likely to have a serious effect on some of the country's poorest farmers, the United Nations has warned. The UN's’ Food and Agriculture Organisation (FAO) estimates losses to the pests could reach $2.2 billion (Dh8.08bn) for winter crops such as wheat and potatoes, and about $2.9 bn for summer crops. The forecast comes on top of dire predictions of millions of job losses and an economic contraction caused by a precautionary lockdown to stem the spread of the coronavirus. Pakistan's government says an intense pest control operation is under way, with aircraft and hundreds of spraying vehicles in the field trying to eradicate the insects. Countries across South Asia, the Middle East and East Africa have been plagued by desert locusts in the past 24 months after an original upsurge began in the Arabian Peninsula in mid-2018. The pests reached Pakistan last spring, causing Prime Minister Imran Khan to declare a national emergency. After a wet winter they bred again in Balochistan province and have recently swept south into Sindh and on towards the Indian border. "The weather has been particularly favourable for locust breeding and the numbers are going up at an exponential rate," Mina Dowlatchahi, FAO representative in Pakistan, told <em>The National</em>. “It is the worst infestation for more than 25 years. Rapid scaling up of operations is critical.” Further swarms are likely to migrate from Iran and the Horn of Africa in June and July. “The combined impact of locusts and Covid-19 on small-hold farmers in Pakistan, men and women, can be severe. They will need support to protect their livelihoods, health and food security,” said Ms Dowlatchahi. Desert locusts may only be a few inches long, but they are considered the most harmful migratory pest on the planet and almost all crops are vulnerable. Adults can eat their body weight each day and form swarms of up to 80 million locusts per square kilometre. Swarms can fly up to 90 miles per day and if good rains fall and conditions are favourable, can increase their numbers 20-fold in three months. As vegetation has dried out in Balochistan, the swarms have moved into Sindh and continued to head south east to India, officials said. Pakistan was caught unprepared for last year's invasion, after a 25-year gap in major swarms. Crop duster planes were not airworthy and equipment was obsolete. Bilawal Bhutto Zardari, chairman of the opposition Pakistan Peoples Party, this month accused the government of being “missing in action” during the plague. He said: “Last year, despite our pleas, provinces were left at the mercy of locusts. If the federal government fails to act, this is another disaster in the making.”