An attack on a health-care provider locks down computers that typically contain electronic medical records, Siegel said, meaning that doctors and nurses can’t access information about their patients’ medical histories, the dosages of drugs that patients require and other critical information.

China isn’t the only country with suspect public reporting. Western officials have pointed to Iran, Russia, Indonesia and especially North Korea, which has not reported a single case of the disease, as probable under-counts. Others including Saudi Arabia and Egypt may also be playing down their numbers.

White House medical advisers now forecast that even if Americans follow unprecedented stay-at-home orders, some 100,000 to 240,000 people could die from the respiratory disease.