Wall Street has started to feel the pressure of economic growth concerns arising from the rapid spread of COVID-19 variants. The Dow Jones Industrial Average lost about 0.8% on Jul 8. The S&P 500 and the Nasdaq Composite indices were also down 0.9% and 0.7%, respectively, on the day. In fact, all these major indices might close lower for the week.Major weakness was observed in spaces like cruise line, airline and home improvement that are more likely to gain from reopening of economies. For instance, there was a decline of more than 1% in each of Carnival Corporation CCL and Norwegian Cruise Line (NCLH) shares on Jul 8. United Airlines UAL and Delta Air Lines (DAL) also lost more than 1%. Nordstrom JWN also declined about 3%, whereas The Home Depot (HD) dipped 1.5%.Chip stocks like Micron Technology (MU), QUALCOMM Incorporated QCOM and Applied Materials (AMAT) declined more than 1% and NVIDIA Corporation NVDA lost 2.3% on Jul 8. Looming concerns over global economic growth majorly led to weakness in the space. Shares of major tech players like Microsoft MSFT, Apple AAPL, Facebook (FB) and Google-parent Alphabet (GOOGL) also took a hit.The global COVID-19 death tally surpassed 4 million on Jul 7. In another disappointing development, Olympics has banned spectators in the summer games to be held at Tokyo from Jul 23 to Aug 8, per a CNBC article. In order to prevent the spread of the virus, Japan has declared a state of emergency from Jul 12 to Aug 22.Also, according to the latest CNN tally, the Delta strain is now found in all 50 states and Washington, DC. Further, this highly contagious and aggressive variant accounted for 51.7% of all new coronavirus infections recorded in the country over the two weeks that ended Jul 3, per the Centers for Disease Control and Prevention data and a CNN report. Notably, the rapidly-spreading mutants induced a widespread fear, putting responsibility on the local and state officials to ramp up the vaccination rate.The 10-year Treasury yield at 1.25% (the lowest since late February) on Jul 8 also highlights that market participants are concerned about the strength of the U.S. economic mend achieved so far, per a CNBC article.ETF Strategies to ConsiderLet’s look at some safer ETF strategies that investors can play keeping in mind certain burning issues that can flare up uncertainty in the near term:Dividend Aristocrat ETFs to Combat Delta Variant ThreatDividend aristocrats are blue-chip dividend-paying companies with a long history of increasing dividend payments year over year. Moreover, dividend aristocrat funds provide investors with dividend growth opportunities in comparison to other products in the space but might not necessarily have the highest yields.‘Dividend aristocrats’ or ‘dividend growers’ are mostly deemed to be the smartest way to deal with market turmoil. Notably, the inclination toward dividend investing has been rising due to easing monetary policy on the global front, and market uncertainty triggered by the pandemic and deceleration in global growth.These products also form a strong portfolio, with a higher scope of capital appreciation as against simple dividend-paying stocks or those with high yields. As a result, these products deliver a nice combination of annual dividend growth and capital-appreciation opportunity and are mostly good for risk adverse long-term investors.Against this backdrop, let’s take a look at some ETFs that investors can consider like Vanguard Dividend Appreciation ETF VIG, SPDR S&P Dividend ETF SDY, iShares Select Dividend ETF (DVY) and ProShares S&P 500 Dividend Aristocrats ETF (NOBL) (read: Dividend Aristocrat ETFs That Deserve a Spot in Your Portfolio).Low-Volatility ETFs to Safeguard Against Market UncertaintiesDemand for funds with “low volatility” or “minimum volatility” generally increases during tumultuous times. These seemingly-safe products usually do not surge in bull market conditions but offer more protection than the unpredictable ones. Providing more stable cash flow than the overall market, these funds are less cyclical in nature. Here are some options -- iShares Edge MSCI Min Vol USA ETF USMV, Invesco S&P 500 Low Volatility ETF SPLV, iShares Edge MSCI EAFE Minimum Volatility ETF (EFAV), iShares Edge MSCI Min Vol Global ETF (ACWV), Invesco S&P 500 High Dividend Low Volatility ETF (SPHD) (read: 4 ETF Zones to Invest in As Volatility Spikes).Quality ETFs to Enhance Portfolio CompositionQuality stocks are rich in value characteristics with a healthy balance sheet, high return on capital, low volatility and high margins. These stocks also have a track record of stable or increasing sales and earnings growth. In comparison to plain vanilla funds, these products help lower volatility and perform rather well during market uncertainty. Further, academic research has proven that high-quality companies constantly provide better risk-adjusted returns than the broader market over the long term.Given this, we have highlighted some ETFs like iShares MSCI USA Quality Factor ETF QUAL, Invesco S&P 500 Quality ETF SPHQ and FlexShares Quality Dividend Index Fund (QDF) targeting this niche strategy. These could enjoy smooth trading and generate market-beating returns in the current market environment (read: 5 Winning ETF Strategies for the Second Half).Want key ETF info delivered straight to your inbox?Zacks’ free Fund Newsletter will brief you on top news and analysis, as well as top-performing ETFs, each week. Get it free >>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 QUALCOMM Incorporated (QCOM): Free Stock Analysis Report Apple Inc. (AAPL): Free Stock Analysis Report Microsoft Corporation (MSFT): Free Stock Analysis Report Carnival Corporation (CCL): Free Stock Analysis Report United Airlines Holdings Inc (UAL): Free Stock Analysis Report NVIDIA Corporation (NVDA): Free Stock Analysis Report Nordstrom, Inc. (JWN): Free Stock Analysis Report SPDR S&P Dividend ETF (SDY): ETF Research Reports Vanguard Dividend Appreciation ETF (VIG): ETF Research Reports iShares MSCI USA Quality Factor ETF (QUAL): ETF Research Reports Invesco S&P 500 Quality ETF (SPHQ): ETF Research Reports iShares MSCI USA Min Vol Factor ETF (USMV): ETF Research Reports Invesco S&P 500 Low Volatility ETF (SPLV): ETF Research Reports To read this article on Zacks.com click here. Zacks Investment Research 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