Madrid, Oct 17 (IANS) The emergency protocol for dealing with a possible case of the Ebola virus was activated at Madrid's Adolfo Suarez-Barajas Airport on a day that saw four people hospitalised with possible symptoms of the Ebola virus.

The airport protocol was activated after a Nigerian passenger on an Air France flight (AF1300) from Paris, but who had started his journey in Lagos, complained of fever, headache, shivering and sweating, causing the plane crew to alert Spanish authorities, Xinhua reported.

The aircraft, which was carrying 156 passengers and seven crew, was taken to a designated area at Barajas airport, the possible Ebola suspect was then taken to the Carlos III Hospital in Madrid, while the remaining passengers were allowed to disembark from the plane after having their details taken and instructed to get in contact with the hospital should they develop signs of fever.

Thursday also saw two further people taken to the Carlos III Hospital, where nursing auxiliary Teresa Romero is being treated for the virus. The first of these was confirmed as someone who had been carried in the same Ambulance as Romero, after she had originally been taken to hospital in Alcorcon Oct 6.

The ambulance carried no special protection against the virus and after taking Romero to hospital was not disinfected for 12 hours during which it carried a further 7 people. The patient, who health authorities confirm is not a medical worker, had formed part of a group of over 50 people considered to be "low risk" of being infected with Ebola.

The third person taken to the Carlos III is a Spanish missionary from the "San Juan de Dios" order, the same as Manuel Garcia Viejo, who died in Madrid of the virus in September.

The missionary, who returned from Liberia Tuesday was taken to the hospital after developing a fever.

Finally a person who abandoned Sierra Leone eight days ago has also been taken to hospital in Tenerife as a precautionary measure after developing a fever.

Meanwhile Romero's state continues to give ground for optimism and Fernando Simon, the Director of the Center for Alerts and Sanitary Emergencies, informed on Thursday that: "the level of the virus in her body has diminished...Her immune system is being able to control the infection."

Simon added that Romero's internal organs were "improving" and there were "clear signs for hope", 17 days after first developing symptoms of the disease.