This photo shows Levi's 501 Blue Jeans by U.S. Clothing Manufacturer Levi Strauss. They were photographed in Berlin, Germany on March 8, 2018.According to a new report, apparel retailers such as H&M, Levi Strauss & Co. could face increased supply chain disruptions. This is because regions in Southern Asia are facing intense lockdowns due to Covid-19 cases rising, fueled by the more contagious Delta variant.The government of Bangladesh has ordered its nearly 170 million inhabitants to stay at home for seven consecutive days due to a new wave of Covid cases. These cases are mainly located along the Indian border. This will likely result in factories being forced to close down across the region, which will stop manufacturing. This is Bangladesh's worst lockdown to date. People are only allowed to leave their homes in emergencies.Panjiva, a business unit of S&P Global Market Intelligence reveals that this is a dramatic reversal of a trend seen earlier in the pandemic. In Europe and Americas, Covid restrictions were stricter, orders from Bangladeshi apparel producers were cancelled.Panjiva's data shows that Bangladeshi apparel exporters to the United States were more resilient than other regions during the pandemic. The firm reported that the shipment numbers for the three months ending April 30 were down just 1.6% compared to the same period in 2019. For comparison, exporters from India dropped 10.1% and 6.4% respectively.H&M was the top-selling retail brand with Bangladeshi presence. Shipments to Bangladesh increased 13.5% between May 31 and May 31, 2019, according to Panjiva. Imports from Levi's dropped 47.8% while those associated with Calvin Klein-owner PVH fell 68.7%.CNBC reached out to H&M, Levi's, and PVH for comment but they didn't respond immediately.A September 2020 analysis by the Peterson Institute for International Economics of U.S. International Trade Commission data shows that China has become less competitive for labor-intensive industries such as apparel. Bangladesh is gaining market share.Retail companies will be affected by additional supply chain disruptions at a time when they already have limited resources due to many factors. Stock levels have been impacted by a shortage of truck drivers and shipping containers. This is usually when retailers place orders for holiday season stock to ensure that shelves are stocked during peak season shopping.Companies run the risk of running out-of-stocks and leaving customers looking elsewhere.Jim Weber, CEO of Brooks Running Company, told CNBC's "Squawk Box," Tuesday that his company now ships in a roughly 80-day period compared to the 40 days it used to take.He stated, "There is no doubt that the supply chain in our industry is strung out."