Earlier this year, a Zika virus was reported in parts of Rajasthan, Madhya Pradesh and Gujarat. Following this, the Indian Council of Medical Research (ICMR) will be conducting phase II trials on a vaccine for Zika developed by the Hyderabad-based vaccine manufacturer, Bharat Biotech. The vaccine developed in Hyderabad is being called ZIKAVAC.
An earlier government press release states, “The first thing is to be prepared for the worst," also adding that it hoped to announce the arrival of ZIKAVAC to the world as early as possible.
Vaccine’s trial phase
“Vaccines need to undergo certain tests, which are a bit unlike tests other pharmaceutical products are subject to,” explains Sreenath RN, from Karnataka Antibiotics and Pharmaceuticals Limited’s (KAPL) Research and Development department. “We are introducing a vaccine to help improve its immunity against a disease. There are certain trials and tests we must subject these vaccines to, in order to ensure the effectiveness of the vaccines.”
There are three phases of trials for a vaccine. The first phase is conducted on healthy volunteers to determine the safety of the vaccine. The second is done to assess the efficacy of the vaccine and to take note of all possible side-effects. In the third phase of trials, vaccines are tested on patients to assess the efficacy, safety and effectiveness of the same.
The ICMR will be taking up phase II trials of the Zika virus vaccine in order to determine if it is safe to administer and to determine its side effects.
“Generally, in phase II trials, we take a small group of people for trials. Usually, around 200 to 300 people are subject to the tests. With vaccines, we are trying to build immunity into a human body. Depending on the vaccine being tested and under the conditions in which it is tested, there may be specific challenges to conducting trials. And within this, dosages, too, may vary from condition to condition,” states Sreenath.
What is the Zika virus
Zika virus is a mosquito-borne disease, which is usually transmitted by the Aedes species of mosquitoes. Symptoms of a Zika virus infection include fever, rash, fatigue, myalgia (muscle pain) and conjunctivitis. They can last for up to one week, though most people do not show any severe symptoms. If a pregnant woman is infected with the virus, it can be transmitted to the unborn child and cause birth defects. The infection in adults can cause certain neurological complications, including neuropathy and myelitis.
It was first reported in 1947 among monkeys in Uganda, and later in humans in 1952 in both Uganda and the United Republic of Tanzania.
In January 2017, the first outbreak of Zika virus was reported in Ahmedabad, following which a second outbreak was reported in July 2017 in Tamil Nadu’s Krishnagiri District.
In 2018, an outbreak in Jaipur reportedly infected around 130 people, of which around 40 were pregnant women.