A visitor sits beside a display of exchange rates at a foreign currency exchange store in Istanbul on Thursday. (Nicole Tung/Bloomberg)

Investors might be watching the financial crisis in Turkey and wondering: How could it affect me?

An economic virus spreading outward from Turkey and through other markets is unlikely, experts say, but it could happen.

In one scenario, European banks that had lent money in the Turkish public and private sectors would face a credit squeeze if Turkey could not make its loan payments.

The Turkish lira, its currency, would continue to drop in value against the U.S. dollar, making those loans — many of which are paid in dollars — more expensive by the day.

If the lender banks don’t get their money, “the banks’ balance sheets become stressed, they stop lending, and the guy on the street can’t borrow,” said Jared Bernstein, who served as the economic adviser to Vice President Joe Biden. “That dampens economic activity, the cost of credit goes up, and that affects interest rates in countries beyond Turkey.”

Turkey’s crisis could grow into a full-blown contagion within weeks or days.

Everything in countries that had big loans to Turkey would become more expensive, because borrowing is more expensive. Those economies would slow.

“That’s the way these things cascade,” Bernstein said. “You have a debt service problem in Turkey, and that affects Turkish debt holdings of banks in larger economies.”

The good news is that Turkey, considered an emerging market, is not Italy or Spain, which also have heavy debts on the balance sheets at public and private institutions.

But Italy has a $2.2 trillion economy, and Spain’s is $1.5 trillion, and both are part of the fabric of the European economy. So an economic infection in one of those countries could quickly ripple across the continent.

Turkey’s gross domestic product is far smaller at $800 billion and change — or close to the entire stock market value of Microsoft. And Turkey, which straddles Europe and Asia, has an economy that is less integrated into Europe, making it less of a threat to its more developed neighbors to the west and north.

Its major trading partners include Germany, Russia and Iran. In 2016, Turkey exported $156 billion and imported $186 billion, resulting in a negative trade balance of $29.6 billion, according to one study.

“Given the limited exposure of foreign banks to Turkish debt, this is far less likely to be the global event that the U.S. housing crisis was,” Bernstein said.

Another way Turkey could infect the international economy is what we are already seeing: Stock markets plummet.

World stock markets dropped last week because investors fear that other so-called emerging markets, such as Brazil, India, China and Russia, will go the way of Turkey.

The MSCI Emerging Markets index is down 10.4 percent this year.

Turkey’s economic distress squeezed stocks early in the week, but then positive returns in the U.S. retail sector, led by Walmart and Home Depot, buoyed the market.

Oil prices and stocks declined midweek on a report that oil inventories are high, which marks the seventh week in a row that oil prices declined.

U.S. markets were holding as of Friday, with the Standard & Poor’s 500-stock index up about 0.6 percent on the week, which means it is 0.8 percent away from its all-time high on Jan. 26, 2018. The S&P is up six of the past seven weeks, with a gain of 4.85 percent. The Dow Jones industrial average was up 1.4 percent on the week. The Nasdaq Composite was down 0.3 percent on the week but still the best performing sector of the year.

“People talk about contagion when they see all emerging markets doing poorly, because investors are pulling money out of emerging stocks and bonds,” said Roger Aliaga-Díaz, a senior economist at Vanguard Group. “Indiscriminate selling is coming from the Turkish headlines. But the fundamentals of the other emerging countries are not bad, and Turkey is just 0.6 percent of emerging markets, so emerging market equities will come back at some point.”

John Lynch of LPL Research agrees.

“Despite the Turkey situation, emerging markets broadly have many solid fundamentals, including economic growth, favorable demographics and attractive valuations,” said Lynch, LPL’s chief investment strategist.

“Emerging market volatility may continue for a little while longer, as these clouds take time to clear,” he said. “We think investors who have maintained some exposure to emerging markets will be glad they did. We suggest modest emerging market allocations, because of the risks involved, and continue to favor U.S. large cap stocks for the majority of equity investing portfolios.”

The country’s economic ills have been simmering for years, as its debt load has grown as high as $300 billion, according to some reports. That is more than one-third of the country’s GDP. The inflation rate is above 10 percent. Its cost of borrowing money has skyrocketed as the value of Turkey’s lira has plunged 40 percent this year, putting the country precariously close to a financial calamity.

President Trump helped deepen the NATO ally’s current crisis this month when he said he would double the tariffs on steel and aluminum that Turkey exports to the United States. The tariffs make it harder for Turkey to capi­tal­ize on its plunging lira through the sale of more steel and aluminum to the United States.

President Recep Tayyip Erdogan hasn’t helped himself, as most of the Western democracies do not like him very much. The United States is especially peeved because Turkey has detained U.S. pastor Andrew Brunson for the past two years relating to terrorist charges after a coup attempt in 2016.

Howard Silverblatt, senior index analyst at S&P Dow Jones Indices, said there does not appear to be a contagion as of Thursday.

The overall market up 18.8 percent, annualized with dividends since March 9, 2009, Silverblatt said.

Many, if not most savers in retirement plans like 401(k)s and Individual Retirement Accounts, probably have some exposure to the 10 emerging market economies, especially if they invest in global indexes of stocks.

Bernstein said stocks are like the canary in the coal mine, warning investors that something may be afoot, but not necessarily a sign of impending doom.

“The stock market today is focused on corporate profitability tomorrow,” Bernstein said. “Stock market volatility right now could reflect concerns about the impact of Turkey on corporate profitability. If there is a squeeze on credit and growth, that’s going to affect corporate bottom lines. That’s why the stock market has been on shpilkes — which is Yiddish for pins and needles.”

Christine Benz, director of personal finance at Morningstar, said the Turkish crisis is further evidence that stock markets are reaching an inflection point after a nine-year bull run.

“Many investors have become complacent about risk in their portfolios,” Benz said. “A portfolio that was 60 percent stock/40 percent bond would be upwards of 85 percent stocks today.”

Benz doesn’t advocate selling off stocks, but she does think that people approaching retirement should consider rebalancing their portfolio to take the gains off the table.

“Young investors should absolutely sit tight with as stock-heavy a portfolio as they can stand,” Benz said. “But investors getting close to retirement, or any other near-term goal that will require them to spend from their portfolios, should be the most attuned to reducing risk in their portfolios.”

Bernstein is doing nothing, which is sometimes the best course.

“What I’m doing is what I always do, which is not reacting to the news of the minute,” he said. “The common investor should not try to time this one out. Just sit tight and see how deep this is.”