West Nile virus can be deadlier than thought. A new study states that people could die even years after recovery. The virus which was considered to be a manageable public health problem is now dangerous and it cannot be underestimated.

The West Nile fever started out in the United States in 1999, with a fatality rate of 4 percent initially. But the spread has led to the death of nearly 2000 people leaving behind 45,000 infected.

According to the Science, the American Society of Tropical Medicine and Hygiene stated that the fatality rate could possibly increase. Once a person recovers from the virus it leaves the victim's body vulnerable to other diseases like kidney failure and many more.

The mosquito borne virus causes symptoms in only 1 out of 5 infected people. It is also considered a relative of the Zika and Yellow fever virus, the virus is believed start with fever and flu but later on it could damage the central nervous system. This will lead to death for some patients and the people who recover are said to do worse later on.

Researchers from Texas have figured out that 13 percent of the patients have died years after the infection as reported on The Wall Street Journal.

The virus is transmitted to humans mostly by mosquitoes; it replicates in the kidneys and also causes severe forms of infection like encephalitis.

Researcher Kristy Murray and her colleagues went through 4162 cases at the Bayer College of Medicine in Houston, Texas. Based on the research they figured out that 557 patients had died out of which 289 of them died in the first 90 days after infection. The situation is more critical for patients who have neurological infections; it is still not certain how the virus leads to long time health problems. A Vaccine must be pushed soon enough to fight the virus.