Microcephaly Current Affairs - 2020

India rebuts CDC Zika alert for Indian travel

The Indian Government has strongly rebutted the US Center for Disease Control and Prevention’s (CDC) travel advisory for Indian travel. The Zika alert will adversely affect tourism.

What is the travel advisory?

The CDC’s travel advisory forbids pregnant women to travel to India as Zika is “endemic” in the country. The advisory also asks travellers to take precaution to prevent mosquito bites and use condoms or not have sex to protect against Zika during travel.

Pregnant women are advised not to travel to areas with risk of Zika because Zika infection during pregnancy can cause serious birth defects.

India was put under Level 2 alert which requires enhanced protection. Level 1 precaution calls for “usual precautions”, and Level 3 advises against non-essential travel.

India’s rebuttal

India has sent a rebuttal to CDC along with all research done on the Zika strain in India, the cases reported, measures taken etc. India has taken strong objection to the use of the word “endemic” because the Zika outbreaks in India are localised and contained within small areas, be it in Gujarat where three cases were reported last year, in Tamil Nadu or the more recent one in Rajasthan.

Research by scientists at the Indian Council of Medical Research has shown that the Zika strains in India are less virulent than in Brazil and are not associated with microcephaly.


Zika is a mosquito-borne infection spread by a virus. Zika was first identified in Uganda in 1947 among monkeys and was detected in humans five years later. Sporadic cases have since been reported across the world since the 1960s. In 2015, Brazil reported a major Zika outbreak. The research’s also linked Zika to microcephaly (i.e. babies born with small and underdeveloped brains).

NBRC researchers decipher how Zika virus causes microcephaly

Scientists from National Brain Research Centre (NBRC) have successfully identified molecular and cellular mechanisms by which Zika virus causes microcephaly. Babies born with microcephaly have significantly smaller head size compared with normal babies.

Key Findings

The researchers found envelop protein (E protein) of Zika virus, which is responsible for entry of virus into brain stem cells, was responsible for arresting proliferation of human foetal neural stem cells and also killing cells that were becoming neuron-like. The combined effect reduces pool of foetal brain cells leading to smaller size of the brain.


The study shows that neutralising E protein of Zika virus can help prevent or reduce its harmful effects in developing foetus. The E protein can be seen as likely therapeutic target. The E protein in Zika virus is mutated and very different from envelop protein of other flaviviruses such as dengue, yellow fever, west nilevirus, and Japanese encephalitis. It was found to be more potent in arresting the proliferation of brain stem cells. The other three envelop proteins were acting in less significant manner.

Zika virus

Zika virus is vector borne disease transmitted primarily by Aedes aegypti mosquitoes, which also transmits dengue. It can also spread through blood transfusion and sexual contact. It is capable of causing serious birth defects i.e. neurological disorders and foetal deformation known as Microcephaly in which infants are born with abnormally smaller heads. Besides possible link between virus and Guillain-Barré syndrome (a condition in which the body’s immune system attacks part of the nervous system) is also suspected. There is no specific treatment or vaccine currently available to treat Zika. The best form of prevention is protection against mosquito bites and clearing stagnant water where mosquitoes breed.