Fears that a deadly outbreak of foodborne illnesses in California could spread to the United States has sent stock prices plunging, with the S&P 500 falling nearly 5% on Wednesday.

The S≈P500 was down almost 9% on Thursday morning to $18,834.25, and the Dow Jones industrial average was down nearly 1.5% to 17,852.75.

The Nasdaq composite was down about 1.3% to 4,719.30.

The worst-hit companies include:Food giants, such as PepsiCo Inc, General Mills Co and Heinz Co, were among those that reported record profits.

The biggest losers were companies such as Nestle USA Inc and Mars Inc.

The company that reported the biggest losses was Sysco Corp., which reported a $4.6 billion loss.

Shares of General Mills fell 2.4% to $21.07 in the stock market, the lowest close in more than a year.

The company also reported a 3% drop in earnings.

The Dow Jones Industrial Average was down 3.5%, or $24.80, to 23,826.85.

The S&p 500 was down 1.9% to 2,823.19 and the Nasdaq Composite was down 0.7% to 7,847.69.