Three episodes of Covid infection found in healthcare professional: report

The emergence of the highly-mutated Omicron variant also led to an enormous rise in Covid-19 cases. There was a surge of reinfection as the variant evaded the immune response from both vaccination and SARS-CoV2 infection.

4 min readPuneUpdated: Apr 20, 2022 07:23 AM IST

Scientists are warning weary governments and populations alike to brace for more waves of COVID-19.(Representational File Photo)

The Pune-based Indian Council of Medical Research-National Institute of Virology (ICMR-NIV) has reported three episodes of Covid-19 infection in a healthcare professional. The report was published in the Journal of Infection on Tuesday. The professional had primary SARS-CoV2 infection, breakthrough infection with Delta and reinfection with Omicron over a 16-month period.

NIV researchers said the findings of the study prove the immune evasion potential of the Omicron variant, even after infection and vaccination. In the case of the 38-year-old healthcare professional from New Delhi, researchers at NIV said the patient had a breakthrough infection with Delta derivative (AY.112) and reinfection with the Omicron sub-lineage BA.2. Although the clinical specimens of the primary infection couldn’t be characterised, the probability of B.1 as an infecting variant would be higher as the infection occurred in October 2020, when emerging variants had not been detected in India.

“During these three episodes of Covid-19 infection, the man did not require hospitalisation and received treatment for symptomatic infection under home isolation,” researchers said.

According to NIV scientists, the fight against Covid-19 is far from over. Although vaccine boosters or third doses have shown an augmentation in the immune response against the Omicron variant, it has been found to wane over time. In such a situation, non-pharmacological interventions in the form of mask, hand hygiene and infection control remain the most reliable weapons to curb the direct transmission of SARS-CoV-2, researchers said.

Read | How Dr Nivedita Gupta, a virologist, scaled up India’s Covid-19 testing process

While vaccination reportedly reduces severity of disease and mortality in Covid-19, it cannot protect individuals from getting a breakthrough infection. Worldwide cases of breakthrough infections have been reported, especially with the Delta variant. India, during the second wave of the pandemic in March-June 2021, was severely affected with the Delta variant of SARS-CoV2. Nationwide genomic surveillance of breakthrough cases showed the predominance of Delta variant in causing the infection.

The emergence of the highly-mutated Omicron variant also led to an enormous rise in Covid-19 cases. There was a surge of reinfection as the variant evaded the immune response from both vaccination and SARS-CoV2 infection.

In the current case, NIV researchers said the healthcare professional from Delhi tested positive with SARS-CoV2 on October 9, 2020. This was a primary SARS-CoV-2 infection, which occurred during the first wave of the pandemic. The symptoms included body ache, fever and a dry cough. However, there were no complaints of breathlessness and the man’s vitals were normal. Post recovery, the patient experienced symptoms of long Covid, including generalised weakness for two to three weeks and insomnia for two to three months.

Story continues below this ad

According to NIV researchers, the patient received the first dose of Covishield vaccine on January 31, 2021, and the second dose on March 3.

The healthcare professional experienced body ache and headache again in November 2021. Subsequently, he tested positive for SARS-COV-2 and while the body ache persisted for two to three days, the person remained afebrile with no other symptoms. Recovery was uneventful except for some forgetfulness (‘brain fog’ linked to Covid-19).

The case represented abreakthrough infection post primary SARS-CoV-2 infection and two doses of Covishield vaccination. However, during the third wave of the pandemic, the healthcare professional developed a headache on January 24, 2022, after being asymptomatic for a period of two months.
He was in home isolation for seven days and the recovery was uneventful, except for increased forgetfulness post reinfection. During these three episodes of Covid-19 infection, the 38-year- old man did not require hospitalisation and he received treatment for symptomatic relief under home isolation.

Anuradha Mascarenhas

Anuradha Mascarenhas is a Senior Editor at The Indian Express, based in Pune. With a career spanning three decades, she is one of the most respected voices in Indian journalism regarding healthcare, science and environment and research developments. She also takes a keen interest in covering women's issues . Professional Background Education: A gold medalist in Communication and Journalism from Savitribai Phule Pune University and a Master’s degree in Literature. Author: She authored the biography At The Wheel Of Research, which chronicles the life and work of Dr. Soumya Swaminathan, the former Chief Scientist at the WHO. Key Focus: She combines scientific accuracy with storytelling, translating complex medical research into compelling public and human-interest narratives. Awards and Recognition Anuradha has won several awards including the Press Council of India's national award for excellence in journalism under the gender based reporting category in 2019 and the Laadli Media award (gender sensitivity -2024). A recipient of the Lokmat journalism award (gender category-2022), she was also shortlisted for the RedInk awards for excellence in journalism-2021. Her debut book At The Wheel Of Research, an exclusive biography of Dr Soumya Swaminathan the inaugural chief scientist of World Health Organisation was also nominated in the Popular Choice Category of JK Paper AUTHER awards. She has also secured competitive fellowships including the Laadli Media Fellowship (2022), the Survivors Against TB – New Research in TB Media Fellowship (2023) and is part of the prestigious 2025 India Cohort of the WomenLift Health Leadership Journey.” Recent Notable Articles (Late 2025) 1. Cancer & Specialized Medical Care "Tata Memorial finds way to kill drug-resistant cancer cells" (Nov 26, 2025): Reporting on a breakthrough for triple-negative breast cancer, one of the most aggressive forms of the disease. Discipline, diet and purpose; How a 97-year-old professor defies ageing'' (Nov 15, 2025) Report about Prof Gururaj Mutalik, the first Head of Department at Pune's B J Government Medical College who at 97 credits his longevity to healthy habits and a strong sense of purpose. 2. Environmental Health (The "Breathless Pune" Series) Long-term exposure even to 'moderate' air leads to chronic heart, lung, kidney issues" (Nov 26, 2025): Part of an investigative series highlighting that even "safe" pollution levels are damaging to vital organs. "For every 10 µg/m3 increase in PM2.5 level, there was 6-8% jump in medicine sales" (Nov 23, 2025): Using commercial data to prove the direct link between air quality and respiratory illnesses in Pune. 3. Lifestyle & Wellness News "They didn't let cancer, diabetes and heart disease stop them from travelling" (Dec 22, 2025): A collaborative piece featuring survivors who share practical tips for traveling with chronic conditions. At 17, his BP shot up to 200/120 mmHG; Lancet study flags why child and teen hypertension doubled between 2000 and 2020'' (Nov 12,2025)--A report that focusses on 17-year-old-boy's hypertensive crisis and reflects the rising global trend of high blood pressure among children and adolescents. 4. Scientific Recognition & Infrastructure For promoting sci-comm, gender diversity: IUCAA woman prof highlighted in Nature" (Nov 25, 2025): Covering the global recognition of Indian women scientists in gender studies and physics. Pune researchers find a spiral galaxy like the Milky Way from early universe'' (December 3, 2025)- A report on how Indian researchers discovered a massive galaxy that existed when the universe was just 1.5 billion years old , one of the earliest to have been observed so far. Signature Beat: Health, Science & Women in Leadership Anuradha is known for her COVID-19 reportage, where she was one of the first journalists to provide detailed insights into the Covishield and Covaxin trials. She has a dedicated interest in gender diversity in health and science, often profiling women researchers who are breaking the "leaky pipeline" in STEM fields. Her writing style is scrupulous, often featuring interviews with top-tier scientists and health experts from various institutions. ... Read More

Click here to join Express Pune WhatsApp channel and get a curated list of our stories

Loading Recommendations...

May 20: Latest News

Live Blog