BETHESDA, Md. (WJZ) — The health of the American Ebola patient has worsened. They were flown in Friday and just over the weekend changed to critical condition.

Tracey Leong has the very latest.

READ MORE: Police On Scene Of Shooting On Reisterstown Road

The patient’s age, gender and name have not been released. We do know they’re being treated at the National Institutes of Health after volunteering in West Africa.

The health of an American aid worker who contracted Ebola while treating patients in Sierra Leone has intensified, changing from serious to critical.

This person is a clinician working with Partners in Health, a Boston-based non-profit organization that has been working with patients in Liberia and Sierra Leone.

READ MORE: Baltimore Police Seeking To Identify Murder Suspect

The patient is being monitored at NIH in Bethesda, the same hospital where nurse Nina Pham was successfully treated after contracting Ebola last year from a patient in Dallas.

There are now nearly a dozen other Partners in Health workers being monitored at hospitals in the US.

In West Africa, the deadly disease has infected 24,000 people and killed 10,000, including 800 health care workers. With the possibility that more aid workers could have been exposed to Ebola, hospitals are preparing for their return.

There are no reports that any additional patients will be taken to NIH. Anyone returning who may have been exposed to Ebola is monitored for 21 days. The CDC is still investigating who the patient may have come in contact with.

MORE NEWS: Maryland Weather: Flash Flood Watch & Warnings Issued For Central Maryland

Partners in Health has been treating patients since last November.