NEW DELHI: No other sample, except the three laboratory-confirmed cases reported from Ahmedabad, has tested positive for Zika virus, the government said today.
The health ministry said that the ongoing laboratorybased surveillance in India has so far tested 36,613 human samples and 16,571 mosquito samples for the presence of Zika virus, and apart from the three, none has tested positive.
All the measures to contain local transmission has been carried out in the affected area, as a matter of "abundant caution", the ministry said in a statement issued late tonight.
The World Health Organization (WHO) had recently confirmed three cases of Zika virus, including a pregnant woman, reported from Gujarat's Ahmedabad, the first in the country.
"As a matter of abundant caution, measures to contain local transmission were carried out in the affected areas. No further samples taken during antenatal screening and acute febrile illness surveillance have tested positive for Zika virus disease.
"The ongoing country-wide Zika laboratory based surveillance in India has so far tested 36,613 human samples and 16,571 mosquito samples for the presence of Zika virus. No other sample has been tested positive apart from the three laboratory confirmed cases reported from Ahmedabad," it said.
It said that the WHO was notified of all the three Zika virus disease cases on May 15 this year.
On November 18 last year, the WHO had declared that Zika disease infection no longer constituted a Public Health Emergency of International Concern (PHEIC).
"Since WHO had already withdrawn the notification of Zika virus disease as a PHEIC, the case was handled as per our existing protocol," the ministry said.
It said cases of vector-borne disease (VBD), mainly dengue and chikungunya, were noticed in Gujarat during postmonsoon period last year.
The state government had accordingly planned fever surveillance, vector surveillance and intense vector control activity.
One of the blood samples collected during laboratory surveillance during this period from Ahmedabad Municipal Corporation limits tested positive for Zika virus.
"This sample was retested at National Institute of Virology, Pune and was further confirmed through positive RTPCR test and virus sequencing at National Institute of Virology, Pune on January 3, 2017.
"This sample was from a 34-year-old female patient admitted to hospital with complaints of fever following delivery of a healthy baby. She had no travel history to any Zika-affected country," the ministry said.
Following the first case, the surveillance was further strengthened and thousands of blood samples were tested as only a thorough investigation can detect cases, given that 80 per cent of the cases are asymptomatic, it said.
Acute Febrile Illness (AFI) surveillance and testing of antenatal cases were undertaken by the state government and ICMR in Ahmedabad.
"This surveillance in total yielded two more cases of laboratory confirmed Zika virus disease (samples collected during January and February 2017).
"The other two cases include a 22-year-old pregnant woman in her 37th week of pregnancy and a 64-year-old male with eight days' history of fever," it said.
The ministry said that the Zika virus disease case was reported as part of an answer to a question raised by MP Vanaroja R in Parliament on March 17 this year.
The ministry said that following the declaration of Zika virus disease as a PHEIC in February, 2016, the government has been taking adequate steps to prevent, detect and respond to the situation.
"The notification for Zika being a PHEIC was withdrawn by WHO on November 18, 2016. However, India continues to maintain high vigilance and surveillance on the issue," the ministry said.
While the National Guidelines and Action Plan on Zika virus disease have been prepared and shared with the states, an Inter–Ministerial Task Force has also been set up.
The government has also constituted a Joint Monitoring Group tasked to monitor emerging and re-emerging diseases.
All the international airports and ports have displayed signage providing information for travellers on Zika virus disease and to report if they are returning from any of the affected countries and suffering from febrile illness, the ministry said.