The 21-year-old, from Kerala (southwest) state, who has not been vaccinated, has not shown any symptoms but is in isolation at her home, Rena K.J., a medical officer in Thrissur district, told AFP.

She tested positive again during a routine check-up before a trip to New Delhi. “The medical teams are in constant contact with her,” Reena KJ said.

The patient was among Indian medical students who fled Wuhan in January 2020 after the virus first emerged in the Chinese city.

She had had mild symptoms and tested positive on January 30, officially becoming India’s first patient with the COVID-19 virus.

31 million cases, 410,000 deaths

Since then, India has recorded nearly 31 million deaths and mourns more than 410,000 deaths, many of them in a devastating wave in April and May 2021.

Experts have warned that a new wave may strike India in the coming weeks, and the authorities have launched a very active vaccination campaign, but it has been hampered by a severe shortage of doses.

The government has set a goal of vaccinating all adults by the end of the year, but the campaign has been delayed, and major cities such as Delhi and many states are starting to run out of vaccines.

India administered more than nine million doses on June 21, after the government launched a new vaccination campaign. But numbers have since fallen to less than three million doses a day.

The country has so far vaccinated nearly 390 million people, or just under 6% of its population, with two doses and 23% with just one.

Kerala is experiencing a sharp rise in COVID-19 cases, with more than a third of India’s cases originating in this state. About 14,500 cases were identified there on Wednesday (out of a total of 43,000 in the country) and authorities announced containment from the end of this week in an effort to stem the spread of the disease.