Zika virus could be transmitted when a healthy person comes into contact with an infected person's sweat or tears, suggests a recent report that establishes a very slight possibility of such a transmission.

Zika virus was previously known to be transmitted through four different routes, first by being bitten by Zika-virus transmitting mosquitoes, having sexual contact with an infected person, from an infected mother to fetus and on coming in contact with the blood of an infected person.

However, a recent study published in The New England Journal of Medicine on Sept. 28 found that there is a slight possibility of Zika virus transmission through sweat or tears.

The study reports Zika virus infection in a healthy 38-year-old patient (Patient 2) who hasn't traveled to any Zika virus transmission zones before acquiring the infection nor had sexual contact with an infected person. Furthermore, Salt Lake City in Utah, where the man lives, is not favorable for Aedes aegypti mosquito that spreads Zika.

The only contact with the virus the young man had was with a 73-year old patient (Patient 1), who was hospitalized with Zika infection. A week before developing the symptoms, the young man visited the latter in the hospital and helped the nurse reposition him on the bed without gloves. It is also said that he had wiped the old patient's eyes while in hospital. Other than possibly tears or sweat, the young man had no contact with blood or other bodily fluids of the old patient.

The 73-year-old acquired the infection during his three-week trip to Mexico. The infection was first mistaken to be Dengue but later was confirmed to be Zika. It was also found that the patient had an extraordinary amount of virus in blood that is about thousandfold higher than the virus load seen in usual infections.

While it was believed earlier that Zika virus is not transmitted through fluids like sweat or tears, the recent evidence suggests that such a transmission might happen with exponentially high loads of virus in blood similar to another potentially fatal Ebola virus infection.

"Given the very high level of viremia in Patient 1, infectious levels of virus may have been present in sweat or tears, both of which Patient 2 contacted without gloves," said Dr. Sankar Swaminathan of the University of Utah School of Medicine.

"We just don't want to create alarm that Zika virus is easily translated from person to person," Swaminathan added as a cautionary note. "We just don't think it is."

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