The Nipah virus is named after a Malaysian village where it was first discovered. It is an emerging infectious disease of public health importance in the South-East Asia.
Nipah virus is naturally found in bodies of fruit bats. Also, it is found in Lyle’s flying fox , and Horsfield’s roundleaf bat. Nipah virus has been isolated from the brain and spinal fluid of infected persons in Malaysia. Infective virus has also been isolated from environmental samples of bat urine and partially-eaten fruit in Malaysia.
Since 1998, NiV has infected 477 people and killed 252. Risk of death among NiV infected patients ranges from 40-70%, although in some outbreaks, it has been as high as 100%. So, Nipah virus Infected patients have a very high risk of death.
Infected bats shed the virus in their excretions and secretions such as saliva, urine, semen and excreta but they do not have any symptoms of infection. The NiV is highly contagious among pigs, and is spread by coughing among pigs. Direct contact with infected pigs was the main mode of transmission to humans when it was first recognized in Malaysia in 1999. 90% of the infected people in the 1999 outbreaks were pig farmers or had contact with pigs.
There is circumstantial evidence of human-to-human transmission in India in 2001. During the Bangladesh outbreak the virus was suggested to have been transmitted either directly or indirectly from infected bats to humans. Strong proof indicative of human- to-human transmission of NiV was found in Bangladesh in 2004.
Symptoms of NiV infection in humans are similar to that of influenza such as fever and muscle pain. In some cases, inflammation of the brain, also known as encephalitis, occurs leading to disorientation or coma. After a healthy person is infected with Nipah virus, it takes 4 to 18 days for symptoms of flu to start appearing.
To confirm has Nipah virus infection in a patient , doctors can do various tests like ELISA, PCR, serology, histopathology, virus isolation or serum neutralization test.
Nipah virus is classified internationally as a biosecurity level (BSL) 4 agent. So it is classified among the high risk microbes.
There is no effective treatment for Nipah virus disease, but a drug called ribavarin may relieve the symptoms of nausea, vomiting, and convulsions. Treatment is mostly focused on managing fever and the neurological symptoms. Severely ill individuals need to be hospitalized and may require the use of a ventilator.
Transmission of Nipah virus from a Human-to another human can be on contact with infected secretions, excretions, blood or tissues.
Standard Precautions in health care like hand hygiene with hand washing and rubbing, facial protection with mask and goggles, gown & gloves , Respiratory hygiene and cough etiquette, environmental cleaning, waste disposal and Prevention of needle stick injuries and injuries from other sharp instruments. A vaccines against NiV are being developed for prevention of the infection.
The main strategy to tackle the Nipah virus problem is to prevent NiV infections in humans. Establishing appropriate surveillance systems will be necessary so that NiV outbreaks can be detected quickly and appropriate control measures initiated.