A 47-year-old man from Kerala’s Thrissur district, died of West Nile fever on Sunday after which the health department of the state is taking measures to control mosquito breeding.
West Nile virus is spread by mosquitoes much like Malaria and is often seen in later summer. It mostly causes milk, flu-like symptoms and but can turn life threatening in few cases.
Dr. Kavita Prabhakar Pai, Consultant Endocrinology & Internal Medicine, Masina Hospital, Mumbai in an interview with HT Digital shared details about symptoms, causes, its differences and similarities with Malaria and more.
What is the West Nile virus?
The West Nile virus (WNV) is spread by mosquitoes. The WNV can infect not just humans, but also birds, mosquitoes, horses, and other mammals. The virus very rarely, can spread through transfused blood, a transplanted organ, or the placenta to a fetus.
It is often seen during late summer. It can also occur year-round in dry, hot-semi arid climates. Most often, the West Nile virus causes mild, flu-like symptoms. But, the virus can cause life-threatening illnesses, such as:
· Encephalitis (inflammation of the brain)
· Meningoencephalitis (inflammation of the brain and its surrounding membrane)
What causes West Nile virus?
West Nile virus is spread to humans through the bite of an infected female mosquito. The mosquitoes get the virus when they bite an infected bird. Crows are the most common birds linked to the virus. But other bird species also have the virus.
It isn’t spread between humans. However, in a few cases it has spread through organ transplant. Health officials think the organ donor acquired the virus through a blood transfusion. All blood is screened for the virus.
What are the symptoms of West Nile virus?
Most people infected with WNV have only mild, flu-like symptoms that last a few days. Symptoms usually appear within 3 to 14 days of infection.
About 20% of the people who become infected will develop West Nile fever. These are the most common symptoms of West Nile fever:
· Fever
· Headache
· Body aches
· Skin rash on trunk of body
· Swollen lymph glands
The more severe form of the WNV affects mostly older adults. It occurs when the virus crosses the blood-brain barrier and can cause:
· Headache
· High fever
· Neck stiffness
· Stupor (a state of impaired consciousness, extreme lethargy, and reduced reactivity to outside stimuli)
· Disorientation
· Coma
· Tremors
· Convulsions
· Muscle weakness
· Paralysis
How is West Nile fever different from Malaria?
The key difference between Malaria and West Nile virus is that Malaria is a mosquito-borne disease caused by Plasmodium parasites while West Nile virus is a single-stranded RNA virus which causes West Nile fever. Female Anophyles mosquito is the insect vector of Malaria while Culex mosquitoes are the insect vectors of West Nile fever.
Many infectious diseases are transmitted by insect vectors such as mosquitoes, lice, fleas, etc. Malaria and West Nile fever are two diseases transmitted by mosquitoes to human. When a mosquito bites a human, infectious agents enter the human body and cause the disease.
– Malaria is a disease caused by a parasite, while West Nile fever is a disease caused by a virus.
– Both diseases are life threatening since there are no vaccines for them.
– Moreover, the symptoms of Malaria are evident immediately, while the symptoms of the West Nile virus do not always immediately become evident.
Can West Nile virus be prevented?
At this time, there’s no vaccine available to prevent West Nile virus. There are recommendations to take the following steps to avoid mosquito bites and WNV:
· Apply insect repellent containing DEET (N,N-diethyl-meta-toluamide) when you’re outdoors. (If you spray your clothing, there’s no need to spray repellent containing DEET on the skin under your clothing.)
· When possible, wear long-sleeved shirts and long pants treated with repellents containing permethrin or DEET since mosquitoes may bite through thin clothing. (Don’t directly apply repellents containing permethrin to exposed skin.)
· Consider staying indoors at dawn, dusk, and in the early evening. These are peak hours for mosquito bites, especially those mosquitoes that carry the West Nile virus.
· Limit the number of places for mosquitoes to lay their eggs by getting rid of standing water sources from around your home.
Treatment
There’s no specific treatment for West Nile virus-related diseases. If a person gets the more severe form of the disease, West Nile encephalitis or meningitis, treatment may include intensive supportive therapy, such as:
· Hospitalization
· Intravenous (IV) fluids
· Breathing support (ventilator)
· Prevention of other infections (such as pneumonia or urinary tract infections)
· Nursing care
Malaria on the other hand is treated with prescription drugs to kill the parasite.
