The acute shortage of the yellow fever vaccine combined with a propensity for corruption could be posing a serious public health risk. Yellow fever vaccines are said to be out–of–stock in the entire country. Yet thousands of Indians continue to travel to countries which the World Health Organisation (WHO) has listed as being at risk of transmitting the disease and from where the disease could be imported. Touts are willing to ensure, for a consideration, that they get the vaccine booklet certifying that they have been vaccinated.

According to travel agents in Delhi and Mumbai, for a price, you can get certified that you have been vaccinated against yellow fever even if you can’t get the vaccine. "When no vaccine is available no matter what price you are willing to pay and your tickets are booked, rather than lose money, people get fake certificates. This is India. If there is demand, there will be supply," said a Delhi travel agency which said that it received at least five applications every day for travel to Brazil, an endemic country.

Quite apart from the moral dimension, the problem with this scenario is that these travellers could unwittingly end up being carriers for a killer disease that is not endemic to India or the rest of Asia. Fake yellow fever vaccination certificates are reportedly freely being sold at a cost of around Rs 5,000–10,000. That seems cheap at a time when reports also indicate that the few doses of the vaccine hoarded by chemists are being sold for as much as Rs 20,000 or more.

Public health experts TOI spoke to fear that India by its inefficiency in managing yellow fever vaccine stocks could be putting Asia, which accounts for about 40% of the world’s population at risk of yellow fever importation.

Yellow fever vaccine shortage was reported from March this year and the union health ministry is yet to remedy the problem caused by stock mismanagement. The office of Dr Sujeet Kumar Singh, Deputy Director General (International Health), Ministry of Health when contacted claimed that orders have been placed and that the vaccines would be available from next month. Such claims have been made by the health ministry since May, but the shortage has only got worse.

So, how serious is the risk? "The mathematical probability of bringing yellow fever into India is dependent on where people travel, for how long they stay there and on the vaccine coverage of the people who live there in an endemic area. You cannot hope that the Aedes mosquito which is abundant in our country will be a poor vector for yellow fever. Once the virus establishes itself in India, you will have enormous consequences to our economy / public health system," said Dr Jacob John of the Community Medicine department of CMC Vellore.

In March 2011, WHO had organised a consultation on yellow fever threat to India and SE Asia in which it was concluded that the threat of introduction of YF into Asia was very real in the age of faster air travel.

At the consultation, it was revealed that two cases of unvaccinated tourists being infected with yellow fever were reported in the US in 1999 and 2002 and both had died. Northern Europe had three imported cases between 1991 and 2002 of which two died. The infection did not spread as the cases happened in non–mosquito season in US and in Europe the vector Aedes mosquito does not occur in Northern Europe.

However the Aedes mosquito, the vector for dengue and yellow fever, is widely prevalent in Asia as Indians are only too well aware. In the consultation, it was warned that stocks of YF vaccine were insufficient if a major epidemic were to occur in Asia.

Despite such warnings, the union health ministry in India remained apathetic to the shortage, which was imminent since the shut–down of the unit in Russia from where government imported vaccines. The requirement for the YF vaccine was about 10.5 million vials, of which the Central Research Institute, Kasauli supplied about a third. The Kasauli unit was shut down in 2008.

While the government used to supply the vaccine at a few hundred rupees from its 15 vaccination centres across the country, the vaccine available in the market costs over Rs 1,500. Today, the same vaccine is being sold for as much as Rs 20,000 in the black market.

Yellow fever vaccination is required for travel to 44 endemic countries in Africa and South America. "It is not for those countries to ensure that travellers are vaccinated. It is for India to ensure, since the risk is to the Indian population. Immigration officers are supposed to check your vaccination status and if a person who visited an endemic country is not vaccinated, the person has to be quarantined. None of this seems to be happening. If sizeable numbers are travelling without vaccination, you are increasing the risk of importation," said Dr Rajeeb Dasgupta of the Centre of Social Medicine and Community Health in JNU.

• Yellow fever vaccination must for travel to 44 endemic countries in Africa and South America
• For a price, flyers can get fake certificates; no vaccine is available in any govt facility or pvt clinic in India
• These travellers could carry the virus back home, which could find a vector in the Aedes mosquito
• Experts warn threat of the virus being flown in by travellers is real, putting entire Asia at risk