The Indian Council of Medical Research (ICMR)-National Institute of Virology (NIV) in Pune has launched a groundbreaking study to assess the impact of the Zika virus on pregnancy and birth outcomes following the outbreak in Pune district last year. This cohort study, titled “Pregnancy and Birth Outcomes after Maternal Zika Virus Infection in Pregnancy during an Outbreak in Pune District,” aims to analyze the effects of Zika virus infection on expecting mothers and newborns, providing critical data for future health interventions.

Background of Zika Virus Outbreak in Pune

Between June and September 2024, Pune experienced a Zika virus outbreak, with 109 confirmed cases, including 43 pregnant women. The outbreak raised concerns about the virus’s impact on maternal health and fetal development, prompting the need for a focused study. Zika virus, transmitted primarily through Aedes mosquitoes, has been linked to adverse pregnancy outcomes, including microcephaly (a birth defect where a baby’s head is smaller than expected) and other neurological complications in newborns.

Study Overview and Objectives

The cohort study will span eight months and target individuals over 18 years of age who tested positive for the Zika virus in Pune. The study encompasses both mothers infected during pregnancy and those currently infected.

The primary objectives of the study are:

Evaluate Pregnancy and Birth Outcomes: Examine complications, delivery outcomes, and the health of infants born to Zika-infected mothers during the Pune outbreak.
Antibody Dynamics Assessment: Analyze how Zika virus-specific antibodies behave over time in affected individuals.
Replication Kinetics Study: Investigate how Indian Zika virus isolates replicate in human placental cell lines and primary cell cultures derived from placental tissues.

By achieving these objectives, researchers hope to gather valuable insights into Zika’s impact on pregnancy, contributing to better management and prevention strategies for future outbreaks.

Research Team and Methodology

The research team comprises leading scientists from the Diagnostic Virology Group of NIV Pune:

Dr. Pradnya V. Shinde – Principal Investigator
Dr. Gajanan Sapkal – Co-Principal Investigator
Dr. Gururaj Rao Deshpande – Co-Principal Investigator

The study will be conducted across multiple Pune areas affected by the outbreak, including Katraj, Kondhwa, Kothrud, Pashan, Erandwane, Deccan, Shivajinagar, Lohegaon, Hadapsar, Mundhwa, Kharadi, and Khadakwasla.

As a cross-sectional study, it will involve collecting data and biological samples at one point in time without follow-up. Researchers will collect blood samples, perform antibody tests, and analyze placental tissues to understand how the Zika virus affects pregnancy and newborn health.

Role of Pune Municipal Corporation (PMC) in the Study

A video conference involving NIV scientists, the Pune Municipal Corporation (PMC), and public health officials highlighted the PMC’s commitment to support the study. Nodal officers have been appointed to coordinate between PMC and NIV teams. Ward medical officers and health officials will assist in survey areas, collect samples, and gather treatment history records.

The PMC has played a crucial role in managing the Zika outbreak and continues to support ongoing research efforts to mitigate the virus’s impact on public health.

Zika Virus and Pregnancy: Health Risks and Concerns

Zika virus infection during pregnancy is associated with several adverse outcomes, including:

Microcephaly: A condition where the baby’s head is significantly smaller, leading to developmental delays and neurological issues.
Congenital Zika Syndrome (CZS): Includes microcephaly, decreased brain tissue, vision and hearing loss, and joint issues.
Miscarriage and Stillbirth: Zika infection increases the risk of pregnancy loss.
Preterm Birth and Low Birth Weight: These complications affect infant health and survival rates.

The Pune outbreak’s 43 Zika-positive pregnant women illustrate the pressing need to study these risks in the Indian context. Of the 43 women, 42 have delivered, while one opted for pregnancy termination due to unknown reasons.

Study’s Expected Outcomes and Public Health Impact

This pioneering study is expected to provide critical insights into the following:

Pregnancy Complications: Evaluate the prevalence of complications like preeclampsia, gestational diabetes, and intrauterine growth restriction in Zika-infected mothers.
Birth Outcomes: Assess neonatal health, including birth weight, head circumference, Apgar scores, and congenital anomalies.
Placental Interaction: Determine how Zika virus affects placental tissues, impacting nutrient and oxygen exchange between mother and fetus.
Antibody Response: Understand the dynamics of Zika-specific antibodies, guiding future vaccine development and immunity studies.
Healthcare Policy: Inform national and regional health policies, enhancing prenatal care and outbreak management protocols.

Dr. Nina Borade, PMC health chief, emphasized the importance of this study in improving Pune’s public health response to vector-borne diseases. By identifying high-risk populations and implementing preventive measures, the study will enhance prenatal care services and outbreak preparedness.

Global Context and WHO Recommendations

The World Health Organization (WHO) has identified Zika virus infection as a public health emergency of international concern, urging countries to conduct research on its impact on pregnancy. The Pune study aligns with WHO’s research agenda, contributing to global data on Zika virus effects.

Data from this study will help India and other affected countries develop targeted interventions, including mosquito control measures, community awareness programs, and improved prenatal care services. The study could also facilitate India’s involvement in global efforts to combat Zika and similar outbreaks.

Potential Challenges and Ethical Considerations

The study faces several challenges, including:

Data Collection Limitations: Given the cross-sectional nature, there will be no follow-up, limiting the understanding of long-term effects.
Participant Compliance: Ensuring participants’ cooperation for sample collection and data provision is crucial.
Infection Risk: Researchers must implement strict safety protocols to avoid Zika virus transmission during data collection.

Ethically, the study will adhere to informed consent protocols, ensuring participants understand the study’s objectives, risks, and benefits before agreeing to participate.

Future Directions and Recommendations

Based on study findings, future directions may include:

Longitudinal Studies: To assess long-term effects of Zika infection on child development.
Vaccine Development: Data will support vaccine research and clinical trials in India.
Enhanced Vector Control Programs: Targeted mosquito control measures in high-risk areas to prevent future outbreaks.
Prenatal Care Improvements: Enhanced screening and care for pregnant women in Zika-endemic areas.

Experts recommend that pregnant women in areas with Zika outbreaks take preventive measures such as:

Using mosquito repellents and wearing protective clothing.
Ensuring proper mosquito control around living areas.
Seeking regular prenatal care and immediate consultation if Zika symptoms appear.

The ICMR-NIV Pune study on the impact of Zika virus infection during pregnancy represents a significant step toward understanding and mitigating the virus’s effects on maternal and neonatal health. By evaluating pregnancy outcomes, antibody responses, and placental interactions, the study aims to provide critical data for improving healthcare policies and preventive measures.

With global concerns about Zika’s impact on pregnancy, the Pune study is poised to contribute valuable insights, aligning India with global efforts to manage and prevent Zika virus outbreaks effectively.