Four senators sent a letter to Amazon urging the company to better protect warehouse workers during the coronavirus outbreak.

In a letter sent to Amazon CEO Jeff Bezos on Friday, Sens. Cory Booker, D-New Jersey, Bob Menendez, D-New Jersey, Bernie Sanders, I-Vermont and Sherrod Brown, D-Ohio, urged him to provide paid sick leave and time-and-a-half hazard pay for its workers, among other measures.

"Any failure of Amazon to keep its workers safe does not just put their employees at risk, it puts the entire country at risk," the senators wrote in the letter. "Americans who are taking every precaution...might risk getting infected with COVID-19 because of Amazon's decision to prioritize efficiency and profits over the safety and well-being of its workforce."

The senators included a list of questions for Bezos seeking more information about what steps Amazon is taking to protect its employees from infection, with a deadline for Amazon to respond by March 26.

The letter also asks whether Amazon would consider covering the cost of testing workers for the coronavirus and whether it would ease disciplinary measures and its "strident efficiency" to give workers enough time to wash their hands. The senators asked Bezos whether Amazon would consider temporarily shutting down any facility where a worker tests positive for the virus.

The letter comes one day after Amazon temporarily closed a Queens, New York delivery station, known as DBK1, after a worker tested positive for the COVID-19 coronavirus. The case marked the first known incident of a U.S. Amazon warehouse employee contracting the disease. On Monday, Amazon confirmed that at least five workers at Amazon warehouses in Spain and Italy contracted the disease.

Unlike employees at Amazon's corporate offices, which have been told to work remotely, many fulfillment center employees and delivery drivers cannot carry out their job duties while working from home.

An Amazon spokesperson disputed the accusations laid out in the letter and said the company has taken "extreme measures" to keep employees safe, including "tripling down on deep cleaning," offering safety supplies and adjusting processes at warehouses to make sure employees are keeping safe distances.

"Our employees are heroes fighting for their communities and helping people get critical items they need in the crisis," the spokesperson said. "Like all businesses grappling with the ongoing coronavirus pandemic, it is not easy as supplies are limited, but we are working hard to keep employees safe while serving communities and the most vulnerable."

Amazon previously told CNBC it implemented "proactive measures" to protect fulfillment center employees, including increased cleaning at all facilities and maintaining social distance by suspending team meetings at the beginning of shifts, halting exit screening and staggering shift start times and break times, among other measures.

On March 9, Amazon logistics workers circulated a petition calling for the company to put in place more "protective measures," including giving workers paid leave, to "ensure the safety of all of its workers and the larger public."

Amazon recently announced it would provide up to two weeks of pay to all employees diagnosed with COVID-19 or placed into quarantine. This is in addition to unlimited unpaid time off for all hourly employees through the month of March, which CNBC previously reported.

The company moved to address the unique needs of fulfillment centers and delivery by launching a $25 million relief fund. The "Amazon Relief Fund" will allow these employees to apply for grants that are equal to or up to two weeks of pay if they're diagnosed with the novel coronavirus, or COVID-19.

Amazon is also raising pay for warehouse and delivery workers by $2 per hour in the U.S. through the end of April.