The CDC will provide laboratories across the U.S. with testing kits for the novel coronavirus, and new cases are expected as more Americans return from the outbreak's epicenter in Hubei province in China, an agency official said on Wednesday.
Initially, the CDC will distribute some 200 kits to more than 100 qualified laboratories across the country and an additional 200 to select international labs, with each kit having the capacity to test 700-800 patient samples.
"By the start of next week, we expect there to be much enhanced capacity for laboratory testing closer to our patients," Nancy Messonnier, MD, director of CDC's National Center for Immunization and Respiratory Diseases in Atlanta, said during a press briefing.
The move follows a Tuesday announcement from the FDA, which issued an emergency use authorization for the CDC's 2019-nCoV real-time polymerase chain reaction diagnostic. Until now, the test had been used exclusively in CDC laboratories. A positive result is indicative of a "likely" infection, FDA said, cautioning that a negative result does not necessarily rule out infection.
On the midday Wednesday press call, Messonnier said no new confirmed cases had been reported in the U.S. since the weekend. But not long after, Wisconsin officials said they had confirmed a new case, bringing the national total to 12.
Messonnier added that 206 individuals suspected of having coronavirus had tested negative while results on 76 others are pending.
CDC also announced that four more flights will arrive on Wednesday and Thursday carrying American passengers evacuating from Hubei's capital, Wuhan, where the outbreak began and continues to be the hardest-hit area. The passengers' health will be assessed by CDC staff upon landing, and all will be quarantined for 2 weeks starting from the time they board the flight home.
"We expect confirmed infections among these and other returning travelers from Hubei province," said Messonnier.
Messonnier said she saw no sign that spread of the virus has slowed, but said the CDC sees a "window of opportunity" to prepare the U.S. in case of broader spread outside China.
"We're preparing as if this is a pandemic -- that's just good common-sense public health -- but of course I'm hoping that it's not," she said.
The current U.S. numbers -- 12 confirmed cases in all, no deaths -- are a stark contrast from those in mainland China, where each day brings news of thousands of new cases and dozens of deaths. On Tuesday alone, an estimated 3,887 new cases and 65 new fatalities were reported.
"The most cases in a single day since the outbreak started," said World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus, PhD, MSc, during a WHO press conference on Wednesday.
So far, 99% of the nearly 25,000 cases have occurred in China, with about 80% originating within Hubei province, of which Wuhan is the capital. Adhanom Ghebreyesus noted, however, that reporting has lagged from some high-income countries. As of this writing, all but two of the 494 deaths have occurred in mainland China.
WHO announced that it had launched a Strategic Preparedness and Response Plan to deal with the outbreak, with $675 million needed to support efforts to prevent, detect, and diagnose new transmissions of the new coronavirus over the next 3 months in the affected countries.
"Our message to the international community is: invest today, or pay more later," said Adhanom Ghebreyesus.
As part of the effort, WHO will send 250,000 coronavirus tests to more than 70 laboratories around the world, as well as 500,000 masks, 350,000 pairs of gloves, 40,000 respirators, and nearly 18,000 isolation gowns to the 24 countries.
During the CDC call, Messonnier was asked about reports from China that a mother there may have infected her unborn baby -- so-called neonatal vertical transmission -- and said the CDC is actively looking for confirmation, but that this scenario would be "pretty unusual" for a respiratory virus.
"However, as we've said all along, there's a lot about this novel coronavirus that we don't know," she said.
Researchers have been struggling to fully understand how the novel virus originated and how best to manage patients.
Writing in Nature, researchers at the Wuhan Institute of Virology found that the novel coronavirus shares 79.5% of the genetic sequence with the 2002-2003 severe acute respiratory syndrome (SARS) coronavirus and is "96% identical at the whole-genome level to a bat coronavirus." But how it got from bats to humans is unknown.
Outside of supportive care, the best approach for treating patients has also yet to be determined, but various therapeutic avenues are being examined, said Carlos del Rio, MD, of Emory University School of Medicine, Atlanta, and Preeti Malani, MD, MSJ, of the University of Michigan in Ann Arbor, in JAMA.
They noted that the first U.S. patient was treated with the antiviral remdesivir, a monoclonal antibody that has been tested as a therapy against Ebola, and that based on past studies suggesting a possible benefit in SARS and Middle East respiratory syndrome (MERS), the HIV/AIDS drug lopinavir/ritonavir (Kaletra) is now being investigated in a Chinese trial as a treatment for the novel coronavirus.