After weeks of essentially shrugging off the coronavirus outbreak, the market finally plunged on Monday.

The S&P 500 lost 3.4%, the Dow Jones Industrial Average gave up 3.6%, and the Nasdaq fell 3.7%. It was the market's worst day in over a year.

Reported cases of COVID-19 surged over the weekend in countries including Italy, Israel, South Korea, and Iran, showing investors the illness has the potential to be a global pandemic, disrupting business and everyday life not just in China but also around the world. 

However, savvy investors know that sell-offs like these often create great buying opportunities as otherwise stellar stocks end up trading at a discount. With that in mind, here are three stocks that I have my eye on if stocks continue to spiral downward on coronavirus fears.

A man looking at a stock chart going down

This was a familiar sight on Monday Image source: Getty Images.

1. Amazon.com

Amazon.com (NASDAQ:AMZN) slipped 4.1% on Monday, momentarily falling below $2,000 a share and a $1 trillion valuation. The stock touched an all-time high last week at $2,185.10 but has since given up 8% on fears of the outbreak.

For a giant company, Amazon stock tends to be volatile, since the company is still valued like a growth stock and is prone to surprises like what happened with its blowout fourth-quarter earnings report. However, there doesn't seem to be a good justification for Amazon to fall nearly 10%, giving up nearly $100 billion in market value, because of the coronavirus.

Like nearly other U.S. retailer, Amazon's depends on China for its supply chain, as many of the goods sold on the platform come from the world's No. 2 economy. But because of its marketplace, many of the products sold on Amazon are redundant. Amazon isn't relying on just one vendor for a certain product line, and neither are shoppers. Furthermore, Amazon's retail competitors in the U.S. are in a much more vulnerable position than the e-commerce giant is if there is a sustained manufacturing slowdown in China. Such an event could cause weak brick-and-mortar retailers to close stores more rapidly and even push some teetering chains into bankruptcy. 

Amazon also has little direct exposure to China, having pulled its marketplace out of the country last year after competition from native companies including Alibaba and JD.com proved too intense.  Its other businesses, including cloud computing and Kindle products, have remained small in the face of the government's regulatory power.

After its latest earnings report, it's clear the company is as strong as it's ever been. One-day Prime shipping is an overwhelming success, and its global Prime membership jumped from 100 million to 150 million in 19 months. COVID-19 is unlikely to significantly hobble the company, but it could do damage to its competitors.  Fears about the outbreak may push the stock lower, but there's no doubt that Amazon, with its long-term focus, will bounce back.

2. Facebook

Another tech giant, Facebook (NASDAQ:FB), was already trading in value range before Monday's sell-off. Shares of the social-media giant fell 4.5% on Monday, though it's puzzling why the stock would get hit harder than the S&P 500. After all, Facebook was already cheap before concerns about the outbreak spread, and the company is well protected from a direct impact from the virus.

First, Facebook has no exposure to China, with the exception of its Oculus virtual reality devices. Second, the company makes money from people using sites including Facebook and Instagram, and screen time would only seem to be encouraged by an outbreak, especially one that's caused millions of people around the world to cancel travel plans and even for events such as the Venice Carnival to be pulled.

As an advertising company, Facebook is dependent on overall economic growth since companies are less to likely to spend in a recessionary climate, but Facebook draws a huge range of advertisers big and small and provides a unique ability to reach potential customers. Businesses that use Facebook depend on its reach, and they aren't suddenly going to give up on just because the coronavirus is rattling markets.

Facebook is also highly profitable and sitting on $54 billion in cash and equivalents, giving the company plenty of resilience against an extended disruption. The stock is trading at a P/E ratio of 21 based on adjusted earnings and backing out its cash sum. Considering its growth rate, the stock already looks like a bargain. If shares keep falling, it will be a downright steal.

3. MercadoLibre

The Latin American e-commerce operator was yet another victim of the coronavirus sell-off on Monday. Shares fell 8.5% alongside the broader market dive. The drop in MercadoLibre (NASDAQ:MELI) shares is particularly perplexing. Though the company is a growth stock with no profits to speak of, it operates only in Latin America, a part of the world that has yet to see significant reports of a coronavirus outbreak.

The company's most recent earnings report shows why it's worth scooping up shares if the stock goes on sale. Not only does it run Latin America's leading e-commerce business, which saw gross merchandise volume jump 39.7% on a currency-neutral basis to $3.9 billion, but it has also emerged as a leader in digital payments thanks to its MercadoPago payment platform.

Latin America is still relatively undeveloped in online payments, giving the company a tremendous opportunity there. In the most recent quarter, total payment volume on MercadoPago nearly doubled, jumping 98.5% to $8.7 billion. That helped propel overall currency-neutral revenue growth of 84% in the quarter.

Like Amazon, MercadoLibre has also been investing its own infrastructure, growing items shipped through MercadoEnvios, its package delivery service, by 47% in the recent quarter. The company also announced plans last week to invest $420 million this year in Mexico, up 46% from the year before. Mexico is its fastest-growing market, and sales jumped 152% to $275 million last year. 

MercadoLibre is probably getting punished because its trades at a high valuation with no profits and a price-to-sales ratio near 15, and the stock has nearly doubled in the past year. But the company isn't threatened by COVID-19, and it has two appealing long-term growth opportunities in e-commerce and digital payments in one of the world's biggest emerging markets, Latin America. A continued sell-off here would set up an appealing buying opportunity for this high-growth stock.