It has now been close to a week since the DREADED
NIPAH VIRUS outbreak hit Kozhikode in north Kerala. The state government would like the rest of the world to believe that its efforts to contain the virus to as small an area as possible have been successful.
To a large extent, that claim does have merit. Even though one more person died on Saturday afternoon, the death was reported from Kozhikode itself.
NiV was first identified during an outbreak of disease that took place in Kampung Sungai Nipah, Malaysia in 1998. On this occasion, pigs were the intermediate hosts. However, in subsequent NiV outbreaks, there were no intermediate hosts. In Bangladesh in 2004, humans became infected with NiV as a result of consuming date palm sap that had been contaminated by infected fruit bats. Human-to-human transmission has also been documented, including in a hospital setting in India.
Symptoms :
The symptoms start to appear within 3–14 days after exposure. Initial symptoms are fever, headache, drowsiness followed by disorientation and mental confusion. These symptoms can progress into coma as fast as in 24–48 hours. Encephalitis, inflammation of the brain, is the dreaded complication of nipah virus infection. Respiratory illness can also be present during the early part of the illness. Nipah-case patients who had breathing difficulty are more likely than those without respiratory illness to transmit the virus. The disease is suspected in symptomatic individuals in the context of an epidemic outbreak.
Diagnosis and Treatment :
Depending upon the exposure to the virus, it can also proceed to further complication like Encephalitis -- inflammation of the brain. This can result in mental confusions and deteriorate to coma.
"The progression is very severe. While the incubation period is long for some, on an average in 90 per cent of cases, the disease manifests itself within two weeks of exposure to the virus," Menon said.
"Those infected should be isolated for at least 10-15 days, till the virulence of the virus settles and our immune system also starts fighting," Vikas Maurya, Head of Department - Pulmonolgy, Fortis Hospital - Shalimar Bagh, New Delhi, told IANS.
There is no real treatment but supportive care is given to the affected patients, which means treating the symptoms differently.
"For example, people suffering from fever are treated for it, for those with breathlessness support is provided to them with artificial ventilators, and for those with seizures or convulsions anti-epileptic drugs are given as a support to the brain," Menon said.
The Kerala government has now recommended using Ribavarin—an anti-viral —as a life-saving measure. It is not a proven treatment, but it is approved because of a few studies that have proved the anti-viral's benefits.
Prevention :
According to CDCA ( Centers for Disease Control and Prevention), Nipah virus infection can be prevented by avoiding exposure to sick pigs and bats in endemic areas and not drinking raw date palm sap.
Additional efforts focused on surveillance and awareness will help prevent future outbreaks. Research is needed to better understand the ecology of bats and Nipah virus, investigating questions such as the seasonality of disease within reproductive cycles of bats. Surveillance tools should include reliable laboratory assays for early detection of disease in communities and livestock, and raising awareness of transmission and symptoms is important in reinforcing standard infection control practices to avoid human-to-human infections in hospital settings (nosocomial infection).A subunit vaccine, using the Hendra G protein, produces cross-protective antibodies against HENV and NIPV has been recently used in Australia to protect horses against Hendra virus. This vaccine offers great potential for henipavirus protection in humans as well.
