Zika virus has spread to several parts of India, finds ICMR

Cases from Telangana, Jharkhand confirm local transmission; experts push for more testing

By Taran Deol
Published: Friday 08 July 2022

The zika virus (ZIKV) has been silently spreading across the country, a study published in Frontiers in Microbiology in June 2022 has reported. 

Surveillance in 2021 showed the virus’s presence in Kerala, Uttar Pradesh and Maharashtra. However, enhanced surveillance confirmed its further spread in Telangana, Jharkhand, Rajasthan, Punjab and Delhi in the same year. 

Detection of cases in new states confirmed local virus transmission, according to the study by Indian Council of Medical Research (ICMR) experts. Cases were reported from Gujarat and Tamil Nadu in 2017 and Rajasthan and Madhya Pradesh the following year. 

“The retrospective surveillance for ZIKV undertaken by us demonstrates the silent spread of this virus to almost all parts of India, with a predominance of the more recent 2018 Rajasthan ZIKV strain,” the authors noted. 

The authors recommended increasing monitoring of not only ZIKV but also dengue and chikungunya — other vector-borne diseases spread by the same Aedes mosquitoes.

The study found 64 ZIKV cases from 1,475 samples taken from 13 states and a Union territory. Tests were conducted between May and October 2021 and the samples were screened and re-tested for dengue, chikungunya and zika. 

Delhi, Uttar Pradesh, Rajasthan, Jharkhand and Telangana reported one case each. The remaining were reported from Kerala. The screening also caught two cases of ZIKV and dengue co-infection from Uttar Pradesh and Kerala and one case of ZIKV, dengue and chikungunya co-infection from Punjab. 

Some 121 cases of dengue were reported — Uttar Pradesh (76), Rajasthan (16), Punjab (10), Madhya Pradesh (9), Telangana (3), Kerala (2), Odisha (2), Uttarakhand (2) Bihar (1). 

This is an epidemiological fallacy, where if you look for something, you will find it, said Dr BR Shamanna, professor at the University of Hyderabad’s School of Medical Sciences. 

“Until recently, we didn’t know much about ZIKV, so we didn’t look for it. But now we know the science and are becoming more conscious of something that has always existed. We just didn’t know of it,” he told Down to Earth.

Cases of Zika, a vector-borne disease, were reported from several Indian states amidst the COVID-19 pandemic. Map: Frontiers in Microbiology, June 2022

Cases of zika, a vector-borne disease, were reported from several Indian states amidst the COVID-19 pandemic. (Frontiers in Microbiology, June 2022)

The self-limiting virus typically shows up as a rash or fever in most people, but the infection is most worrisome among pregnant women.

Dr Shamanna said:

 “If a woman gets infected with ZIKV in the first trimester, it has a deleterious effect on the foetus. The brain doesn’t grow and the child’s survival becomes very difficult. If the child survives, there are many congenital anomalies.”

While such cases have been reported from Brazil, none have been confirmed in India. “It’s tough to retrospectively confirm if a ZIKV is a reason behind congenital anomalies,” he added.

The ICMR experts stressed the need for ante-natal ZIKV screening.

The authors noted: “It is also critical to strengthen linkages of ZIKV surveillance sites with the existing newborn birth-defect screening sites in the country. It will help understand the spectrum of the disease in babies born to ZIKV-infected mothers.”

The vector-borne disease spreads by the bite of infected Aedes mosquitoes, mainly Aedes aegypti and Aedes albopictus. 

Symptoms of patients included fever (56 cases), rash (52), arthralgia, also known as joint pain (30), conjunctivitis (23), myalgia or muscle pain (14) and weakness (9). Other clinical manifestations are headache, diarrhoea, respiratory distress, vomiting and seizures. 

If more cases are reported, there is a better chance of controlling them in the future. The study’s findings only strengthen the argument in favour of more robust screening and testing for ZIKV. 

While the COVID-19 pandemic has been devastating, it has resulted in massive upscaling of RT-PCR testing laboratories across the countries. The authors suggested we take advantage of this and use the system to ramp up screening for ZIKV. 

Subscribe to Daily Newsletter :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.