Last week, Quest Diagnostic DGX issued its periodical media statement on the company’s COVID-19 testing-related business performance. Following a dull second-quarter performance in terms of testing due to the declining case counts, this time the company noted about a dramatic increase in testing demand through July to September, as the United States is seeing a surge in the Delta variant-led cases.Let us delve deeper.On a cumulative basis, as of Sep 14, the company has performed and reported 48.7 million molecular diagnostic tests. The test capacity per day remained at 300,000.For the same period, antibody (serology) tests performed and reported were 6.9 million on a cumulative basis. For this test, the test capacity per day was 350,000.The average turnaround time of both types of tests mostly remained at 1 day.COVID-19 Testing Trajectory Through Q3 MonthsIn July, the company first reported about an increase in the testing demand and positivity rates owing to the emergence of the Delta variant. The company claimed that its molecular diagnostic tests are effective in detecting individuals infected with this new dominant strain of SARS-CoV-2 circulating in the United States, as well as other known circulating strains.Following this, the company increased the number of sites for individuals to access the $0 out-of-pocket COVID-19 diagnostic test option through its online consumer-initiated testing platform, QuestDirect, in order to include approximately 700 of Quest Diagnostics patient service centers.Image Source: Zacks Investment ResearchIn August, with a further surge in cases, the company stated about a difficulty in pooling specimens due to the steady increase in the average positivity rate. However, Quest Diagnostic confirmed that it continued to perform and report the majority of COVID-19 diagnostic tests within 1 day.Same month, it also announced that it has become one of the core laboratory providers for K-12 COVID-19 school testing in Pennsylvania, through its collaboration with Ginkgo Bioworks. Further, under its partnership with eMed, the company is now offering clinician-guided rapid COVID-19 antigen testing to employers for a safer workplace environment.In September, the Biden Government launched its “Path Out of the Pandemic” plan, which, while emphasising more on an enhanced access for testing, has came as a major breakthrough for Quest Diagnostics.As per the plan, the Department of Labor’s Occupational Safety and Health Administration (OSHA) will develop a rule that will require all employers with 100 or more employees to ensure their workforce is fully vaccinated or else it will require any workers who remain unvaccinated to produce a negative test result on at least a weekly basis before coming to work. The OSHA will issue an Emergency Temporary Standard (ETS) to implement this requirement.Once the OSHA rule is implemented, the company expects demand for its testing to rise significantly. Currently, Quest Diagnostics is evaluating opportunities to scale its laboratory testing capacity and rapid antigen test inventory.Raised Outlook for 2021Earlier this month, Quest Diagnostics noted that since its second-quarter earnings release on Jul 22, the COVID-19 molecular testing volumes have been higher than anticipated on the Delta variant spike. Going by the current situation of the daily increase in case count, Quest Diagnostics raised it guidance for the full year.The full-year net revenues are currently estimated in the range of $9.84-$10.09 billion, up from the earlier band of $9.54-$9.79 billion, indicating an improvement of 4.3-6.9% (earlier growth expectation was 1.1-3.7%) from 2020.The adjusted earnings per share (EPS) too has been raised to the range of $11.65-$12.35 from the previous projection of $10.65-$11.35.Share Price PerformanceShares of the company have gained 31% in a year’s time as against the industry’s 26.8% slump.Zacks Rank and Key PicksCurrently, Quest Diagnostics carries a Zacks Rank #3 (Hold).A few better-ranked stocks from the Medical-Products industry include VAREX IMAGING VREX, Envista Holdings Corporation NVST and BellRing Brands, Inc. BRBR, each carrying a Zacks Rank #2 (Buy). You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.VAREX has a long-term earnings growth rate of 5%.Envista Holdings has a long-term earnings growth rate of 27.4%.BellRing Brands has a long-term earnings growth rate of 29.1%. Breakout Biotech Stocks with Triple-Digit Profit Potential The biotech sector is projected to surge beyond $2.4 trillion by 2028 as scientists develop treatments for thousands of diseases. They’re also finding ways to edit the human genome to literally erase our vulnerability to these diseases. Zacks has just released Century of Biology: 7 Biotech Stocks to Buy Right Now to help investors profit from 7 stocks poised for outperformance. Recommendations from previous editions of this report have produced gains of +205%, +258% and +477%. The stocks in this report could perform even better.See these 7 breakthrough stocks now>>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Quest Diagnostics Incorporated (DGX): Free Stock Analysis Report VAREX IMAGING (VREX): Free Stock Analysis Report Envista Holdings Corporation (NVST): Free Stock Analysis Report BellRing Brands, Inc. (BRBR): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research