Since the beginning of June, India has been experiencing the worst outbreak caused by the Chandipura virus for more than 20 years. At least 38 people have died from the infection, most of them children and adolescents.
This rod-shaped virus belongs to the same family as the rabies virus. It is mainly SUBMITTED by sandflies, small midges whose females feed on blood. However, mosquitoes and ticks can also spread it.
Initial symptoms are similar to those of the flu, but can quickly progress (within 24 to 48 hours) to a encephalitisin other words inflammation and edema (swelling) affecting the brain, which can lead to coma or even deathChildren under 15 are the most vulnerable patients.
The exact way the virus enters the central nervous system (brain and spinal cord) and causes encephalitis is still poorly understood. It is thought that the virus is transmitted through the saliva of the infected insect, when it bites to take its blood meal. The virus then spreads into the bloodstream, and infects immune cells called monocytes (a type of white blood cell). There, it multiplies, protected from the immune system. Then transported to the central nervous system, it enters the brain by disrupting the blood-brain barrier, the shield that is supposed to protect this essential organ (as well as the spinal cord).
Six hours after the onset of infection, the Chandipura virus secretes a protein called phosphoprotein into brain cells, which may explain why the death comes so quickly.
Unfortunately, at present there is no antiviral treatment or vaccine.
A relatively recent threat, accentuated by climate change
The Chandipura virus is named after a village in the state of Maharashtra, India. It was there that it was first identified in 1965. However, the first major outbreak did not occur until 2003, in the southern state of Andhra Pradesh, India. That year, 329 children have tested positive for the virus, and 183 have died from the infection. In 2005, during an outbreak in the northwestern Indian state of Gujarat, 26 cases were identified, with a high mortality rate (78%).
The most recent outbreak, also in Gujarat, had affected 100 people. It had particularly serious consequences for children under 15 who had been infected. At the time, the rapid spread of the virus and the severity of the symptoms had raised concerns among public health authorities.
Since the virus was discovered in 1965, most cases have been in the Indian subcontinent. However, things may be changing: the virus’s geographic distribution is expanding beyond India’s borders. It has been identified in sandflies, for example. in West Africa in 1991 and 1992as well as in hedgehogs in senegal (between 1990 and 1996). Antibodies against Chandipura virus have also been detected in wild monkeys in Sri Lanka in 1993, suggesting that they too had come into contact with the virus.
Macaques in Sri Lanka have been infected with the Chandipura virus. geogphotos/Alamy Stock Photo
The emergence of the Chandipura virus is probably linked to climate change, as its spread is facilitated by increasing temperatures.
Several other viral diseases spread by insects (arboviruses, for “ARthropod-BOrne VIRUSes” in English) have also progressed in recent years due to climate change. This is particularly the case for several diseases caused by viruses transmitted by mosquitoes, what is the Zika virusthe one from dengue or even the virus Nipah.
