However, the first case was confirmed on 4 January and two more cases were confirmed by the end of March and only a handful of people at the Indian Council of Medical Research and the Ministry of Health and Family Welfare were privy to the information.
Dr Soumya Swaminathan, Director General, Indian Council of Medical Research (ICMR) said that the three patients had no overseas travel, therefore the infection could have been acquired locally.
"There is no need to panic. All three cases recovered," she asserted.
Reported cases could possibly be locally transmitted
The first case was discovered through an Acute Febrile Illness (AFI) surveillance between 10 – 16 February 2016 when a 64-year-old male's sample was found to be positive for Zika virus at the BJ Medical College.
The second case involved a 34-year-old pregnant woman who delivered a healthy baby at BJMC on 9 November 2016 and developed a low grade fever after delivery. A sample was then referred to the Viral Research & Diagnostic Laboratory (VRDL) at the BHMC and found to be positive for Zika virus.
The third case was a 22-year-old pregnant woman in her 37th week of pregnancy who was discovered through the Antenatal clinic (ANC) surveillance between 6 – 12 January 2017 at BJMC.
All samples were confirmed through testing at the national reference laboratory, National Institute of Virology (NIV), Pune on 4 January 2017 onwards. It is, however, unknown as to how the virus was transmitted, or the specific strain that infected the three individuals.
Ministry of Health officials said all states were following the standard protocols to prevent an outbreak of the disease, with guidelines and action plans to be implemented with the states.
The surveillance of the Zika virus in India has been outstanding and it is particularly commendable that the Ahmedabad hospital suspected that the cases may have been caused by the Zika virus and quickly diagnosed them.
Delay of report an ethical violation
However, the attitude of the health officials has sparked debate as the withholding of information from the concerned civic authorities and the public is both a technical and ethical problem.
According to the norm, when an authority receives a report about a disease under global surveillance such as Zika –it needs to institute a wide range action at two levels; one at the scientific and academic level and another to the public health authorities involved in disease control at the local level.
The detection of the Zika infection should have been announced widely to the academic community, as well as clinical and research facilities. The information would help alert states to strengthen and/or set up surveillance and diagnostic systems.
Local authorities should also be warned as information campaigns to reach out to communities to strengthen the practice of personal prophylaxis can be implemented.
Public health assured to be in good state
However, as India has not adopted any code of ethics for the practice of public health, chief secretary J N Singh said that since the Zika infection was endemic to Ahmedabad and there was no cascading number in cases of Zika, "the government consciously did not go public with the cases". The BJMC lab did inform the NIV which in turn informed ICMR and the Union government according to protocol.
According to Ahmedabad Municipal Corporation, it had no information about positive Zika cases and took only preventive measures as per state government's directives.
It also said there was no established link between the three Zika-infected persons.
AMC commissioner Mukesh Kumar declined to provide information about where the patients were informed about the Zika infection but instead reassured that "public health in Ahmedabad is in a good state, no need to get scared."
But the WHO says that although the findings suggest low level transmission of Zika virus, it is impossible to rule out that new cases will not occur in the future.
It advises India to strengthen surveillance to better characterise the intensity of the viral circulation and geographical spread, and monitor Zika virus related complications. MIMS
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