A US federal air marshal was stabbed with a syringe at the Lagos, Nigeria airport on Sunday. The substance inside the syringe is undergoing testing.

The as yet unidentified air marshal was travelling with a team of people when he was attacked inside the airport, the TSA's Transportation Security Operations Center announced Monday. The assault appears to be an isolated incident.

The State Department, FBI, and CDC responded to the Lagos Airport to assess the situation.

"After consultation with the consulate and physicians, the [federal air marshal] was given precautionary medication," the TSA alert read.

Nigeria is one of the countries affected by the Ebola outbreak sweeping across West Africa, with 16 confirmed cases, and seven suspected and confirmed deaths.

One of those deaths was Liberian-American husband and father Patrick Sawyer, who died days after flying from Liberia to Lagos.

The air marshal, his team, and the syringe were transported to the United States, where more testing was conducted.

"Out of an abundance of caution, the Centers for Disease Control and Prevention conducted an on-scene screening of the victim when United Flight 143 landed in Houston early Monday morning," the FBI reported.

"The victim did not exhibit any signs of illness during the flight and was transported to a hospital upon landing for further testing. None of the testing conducted has indicated a danger to other passengers."

Both the CDC and the FBI are investigating the incident.

The deadly Ebola virus typically causes fever, diarrhea, vomiting, headache, joint pain, and other symptoms. The disease is transmitted by coming into contact with the bodily fluid of an infected person, or touching objects such as needles that have come into contact with infected bodily fluid.

The CDC recommends proper sterilisation of medical equipment, and wearing protective clothing to decrease the chances of infection. However, even with these precautions, Ebola transmissions have been reported.

There is no cure for Ebola virus disease. The mortality rate of the current outbreak is 60 per cent.