On his arrival on June 27, Immigration officials told him the card certifying him as being vaccinated against the tropical disease did not list the origin and batch number of the vaccine. Hours later, Jacob found himself in the airport's Quarantine Hospital at Andheri (East).

``They did not even know where Malawi is. They kept screaming at me, asking why I went to Africa to work when no one is ``supposed to go there''. I was not allowed to contact my family in Kerala,'' he said, weeping.

Mathew Koshy (29), who flew in from Lagos, Nigeria, on the same day, was told his yellow fever card did not mention the centre wherehe had been vaccinated. Says an incredulous Koshy: ``The same card was considered valid when I entered this country last month. It was only when they asked me to pay $ 100 that I understood what was happening.'' Fortunately, Koshy was bailed out by his company after only a day's confinement.

Peter Omoregie (38) though did not get off lightly. The Nigerian pharmacist, who arrived on the same flight as Koshy, says though his papers were in order he was threatened with qaurantine because he refused to pay $ 100 to an Immigration official. He told Express Newsline: ``Initially, I was asked to pay $ 400, which was reduced to $ 100. I was told there is a war between Pakistan and India in Kargil and every passenger has to compulsorily pay up,'' he laughs, marvelling at the official's ingenuity.

Every year, over 200 persons are quarantined for yellow fever. Yet, even by the airport health officer's own admission, not a single case has been detected among the detenues so far. Last year alone, 240 passengerswere quarantined and an additional 69 in 1999. Though quarantine is stipulated by the World Health Organisation since yellow fever like the plague is a notifiable disease, airport sources admit that Immigration officials here arbitrarily pick on technicalities.

`Wrong signatures and incorrect stamps' on their yellow fever check cards are among the many reasons that regularly confront passengers who do not fork out the various sums demanded by Immigration officials, airport sources reveal. The sums, which start from $ 50, usually correlate with the passenger's profession, sources add.

Every passenger disembarking from African, Central American and certain South American tropical countries are required to furnish a yellow fever check card certifying them as vaccinated against the disease. Passengers suspected of carrying the virus are despatched to the airport's quarantine hospital at Andheri for the mandatory 6-10 day incubation period.

Airport Health Officer Dr J S Murthy told Express Newslinethat not a single case has been detected among passengers till date. Besides, he says, among the thousands of persons entering the country from the target countries 99.09 per cent of them have their papers in order.

Ironically, ever since the health counters at both the Immigration and Customs desks were shut down at airports across the country in 1984, passengers are being identified for quarantine by Immigration officials, who have no medical background. A medical inspection room has been retained but in a double irony, the personnel process passengers only after they are picked out by Immigration officials.

Detenues at the quarantined hospital say the centre, run by the central Ports and Airports Health Organisation, has no medical facilities. Neither does it have a kitchen. Hence, fast food is ordered from stalls in the vicinity by sympathetic staff moved by the detenues' plight.

Matron Susheela Nair, who has been with the hospital for 21 years, confirms that none of the passengers quarantined therehave ever shown symptoms of yellow fever. ``In my 30 years of service (nine years in Chennai), I have never met a yellow fever patient,'' she told Express Newsline, adding that precautionary measures are important.

Dismissing corruption charges, Assistant Foreign Regional Registration Officer (Immigration), Priya Phadke, placed the onus on the health staff. ``You cannot hold us responsible. Immigration detains passengers without cards or those whose cards have expired or in which alternations are made. We hand them over to the health officers for scrutiny,'' she says.