- At least 17 of the 18 patients infected in an outbreak of the Nipah virus in India have died, according to the World Health Organisation.
- Nipah is a deadly virus that can be transmitted between people. It has killed between 40% and 75% of infected people in past outbreaks.
- Fruit bats are the natural host of the disease, and t here is no cure or vaccine.
At least 17 people in southern India have died in an outbreak of the rare and extremely deadly Nipah virus, according to the World Health Organisation (WHO).
Nipah is considered a newly emerging deadly virus – scientists only found out that it could jump from bats to other species, including humans, within the past 20 years. The disease is currently incurable and can be transmitted from person to person. It has killed between 40% and 75% of infected people in most outbreaks.
These statistics indicate that Nipah has the potential to cause a deadly pandemic, which is why the World Health Organisation lists Nipah as an urgent research priority, alongsidediseases like Ebola and SARS.
The current outbreak has been particularly deadly, with 18 confirmed cases and 17 deaths so far.
Many of the victims have been from one family in the city of Kozhikode in Kerala,according to a report in The Lancet medical journal. According to that report, experts have been able to trace contacts for victims, which should help stop the spread of the virus. At least 1,400 people have been quarantined while doctors wait to see if anyone displays signs of infection, according to ABC News. But experts say they believe the outbreak has been contained.
A little-known virus
Nipah first appeared in Malaysia in 1998, when 265 people became infected with a strange illness that caused encephalitis, or brain inflammation, after they came into contact with pigs or sick people. In that outbreak, 105 people died, a fatality rate of 40%.
Since then, there have been a number of smaller outbreaks in India and Bangladesh, with about 280 infections and 211 deaths – an average fatality rate of 75%.
When the first infections jumped from pigs to humans, authorities killed more than a million pigs to try to stop the spread of the disease. Since then, however, researchers have identified several fruit bat species as the natural hosts of the virus. In some cases, humans have been infected after drinking sap from date palms that bats may have contaminated.
Bats were found in a well used by a family in Kozhikode, which may be the initial source of the outbreak, though investigations into the source are still ongoing.
Symptoms for Nipah have varied depending on the outbreak. Many patients first experienced fever and headache, followed by drowsiness and confusion. Some patients have also shown respiratory problems and flu-like symptoms while infected. In other cases, symptoms progressed to a coma within a day or two.
People who survive the initial infection can have lasting health issues, including personality changes and persistent convulsions. In some cases, the virus has re-activated in patients months or years after exposure, causing illness and death.
Close contact with sick animals or people can spread the disease – in the current outbreak, at least one of the deceased people was a nurse who treated sick patients. A study of Nipah virus transmission suggested that infected patients’ saliva is likely to spread the infection.
This story was originally published May 21 and has been updated with more recent information from the WHO.