The Union health ministry has said in its revised protocol for clinical management of Covid-19 that the majority of transmission is believed to happen through the “airborne route” and droplets released when the infected person coughs, sneezes or talks.

This is a major change from last year’s protocol, which said that transmission occurs through close contact, mainly through respiratory droplets that are released when the infected person coughs, sneezes or talks.

In this year’s protocol released on Monday, the health ministry said that the droplets released from a person may also land on surfaces, where the virus can remain viable for some time, depending on the type of surface. “Infection can also occur if a person touches an infected surface and then touches his or her eyes, nose, or mouth [known as fomite transmission],” it said.

On May 20, the Centre’s Principal Scientific Adviser K VijayRaghavan had also said that aerosol particles “can be carried in the air up to 10 metres”, highlighting how better ventilation can decrease the risk of transmission of the infection. Aerosols are small solid and liquid particles suspended in the air.

The ministry has also added ivermectin tablets for the treatment of mild Covid-19, reported the Hindustan Times. The ministry advised taking ivermectin once a day on an empty stomach for 3-5 days. It warned against giving the drug to pregnant and lactating women.

Ivermectin is used for treating parasitic infections in animals, according to the United States Food and Drug Administration. The FDA has advised against using the drug for the treatment of Covid-19, saying that it has received multiple reports from patients who needed medical support and were hospitalised after self-medicating with ivermectin intended for horses.

The revised protocol also advised against using steroids for mild cases. “If symptoms persist beyond 7 days [persistent fever, worsening cough etc] consult the treating doctor for treatment with low dose oral steroids,” it said.

On May 22, the Centre had said that the irrational use of steroids for treating coronavirus patients was contributing to the increase in cases of mucormycosis, or “black fungus”. Mucormycosis is caused by a fungus named mucor, which is found on wet surfaces. The symptoms of the infection include headache, fever, pain under the eyes, nasal or sinus congestion, and partial loss of vision, among others.

The new protocol listed fever, cough, headache, sore throat, nausea, vomiting, vomiting, loss of smell, loss of taste, altered mental status, myalgia (muscle pain) and dyspnoea (difficulty in breathing) as symptoms of the infection.

“Older people and immune-suppressed patients in particular may present with atypical symptoms such as fatigue, reduced alertness, reduced mobility, diarrhoea, loss of appetite, delirium, and absence of fever,” the protocol said. “Children might not have fever or cough as frequently as adults.”

It said that citizens aged above 60 and those with comorbidities were at risk of a severe case of the infection.

Meanwhile, India on Wednesday reported 2.08 lakh new cases in the last 24 hours, taking the overall tally past 2.71 crore since the pandemic first broke out in December 2019. The toll rose by 4,157 to 3,11,388, while the active caseload declined by over 91,000 to 24,95,591.

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