What we know of Covid-19 now: Updated symptoms, modes of transmission, immunity and complications – The Indian Express

Written by Abhishek De | New Delhi | Updated: July 19, 2020 9:32:54 pm Coronavirus (Covid-19) Symptoms, Treatment: A health worker speaks with a child at an isolation center for Covid-19 at CWG in New Delhi

Coronavirus (Covid-19) Symptoms, Treatment: What began with a handful of infections in the Chinese city of Wuhan last December, has now spread to over 216 countries, with cases of the novel coronavirus infection crossing 14 million worldwide, including more than 6 lakh deaths.

While initially animal-to-person spread of the disease was suspected, by January, person-to-person spread of the virus was reported around the world. In the first week of March, the World Health Organization (WHO) declared Covid-19 a pandemic, triggering unprecedented national lockdowns, upending economies and stretching healthcare systems to the brink.

However, even after seven months, scientists are still to come to a conclusion on the source of the virus, how the disease is transmitted, why some cases are more severe than others and whether people who have recovered from Covid-19 can get it again.

Till now, 12 symptoms of the virus have been identified by the US health protection agency Centers for Disease Control and Prevention (CDC). Last month, the agency included congestion or runny nose, nausea, and diarrhea as possible indicators of the infection.

The list already included fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell and sore throat. They may appear 2 to 14 days after exposure to the virus.

Recently, in several countries, including India, children have often shown some symptoms associated with a rare illness called Kawasaki disease about 2-3 weeks after getting infected with coronavirus. These symptoms include rashes and inflammation. Last month, the World Health Organization (WHO) termed this new illness as multi system inflammatory disorder.

The WHO recently updated its brief on Modes of transmission of virus causing COVID-19 and formally acknowledged evidence emerging of the airborne spread of the novel coronavirus. In the brief, the WHO has formally acknowledged the possibility that the novel coronavirus can remain in the air in crowded indoor spaces, where short-range aerosol transmission cannot be ruled out.

However, the WHO still maintains that transmission through respiratory droplets when an infected person coughs, sneezes, talks, or sings is still understood to be the primary mode of transmission of the virus.

It also mentions another type of transmission called fomite transmission. It refers to transmission through infected surfaces such as doorknobs, elevator buttons, handrails, phones, switches, pens, keyboards and, if not disinfected, even a doctors stethoscope.

Researchers across the world are studying whether antibodies developed by the body in response to the virus can provide permanent immunity. A new study by Kings College London has found that those recovering from Covid-19 may have antibodies for only a few months.

Upon analysing the immune response of more than 90 people, the researchers found that antibody levels peaked about three weeks after the onset of symptoms and then started declining. Thus, the findings suggest that people can become reinfected just like the common cold and other kinds of flu.

Meanwhile, Dr Randeep Guleria, director of AIIMS and one of the experts leading the countrys novel coronavirus disease response, has also said cell-mediated immunity, an immune response that does not involve antibodies, may also be protecting the body.

While initially Covid-19 was thought to be just a respiratory infection, patients were now suffering from strokes and neurological disorders, including inflammation, psychosis and delirium, and some have also complained of weakness after weeks.

Lung damage, known as lung fibrosis, and blood clots in the pulmonary artery Pulmonary Thrombo Embolism or PTE have also been seen in persons who have recovered from very severe cases of the disease. A study by University College London researchers revealed 43 patients who suffered either temporary brain dysfunction, strokes, nerve damage or other serious brain effects.

Besides, Dr Guleria also said medical examination of patients with severe illness showed that even months after recovery, their lungs continued to be in bad shape, and they required oxygen at home.

According to the World Health Organisation, there is no evidence so far that pets or animals can transmit the disease to humans even though several dogs and cats in contact with infected humans have tested positive for Covid-19.

It has been found that ferrets appear to be susceptible to the infection and it has been found that both cats and ferrets were able to transmit Covid-19 to other animals of the same species.

Recently, minks raised in farms have also been detected with the virus. In a few instances, the minks that were infected by humans have transmitted the virus to other people. These are the first reported cases of animal-to-human transmission.

To date, there are no specific vaccines or medicines to prevent Covid-19 and the drugs being used only help reduce the viral load. The US Food and Drug Administration (FDA) has granted emergency-use authorisation for antiviral drug remdesivir while the UK government has approved the use of a low-cost, widely used steroid dexamethasone.

India has also authorised off-label use of immuno-suppressant drug tocilizumab and convalescent plasma therapy on specific groups of patients apart from oxygen or mechanical ventilation. Moreover, India has also been using hydroxychloroquine as a prophylactic drug.

Besides, India is also using Favipiravir for Covid-19 treatment. Last month, Glenmark Pharmaceuticals launched the drug under the brand name FabiFlu, making it the first oral Favipiravir-approved medication in India for the treatment of Covid-19.

The Indian Express is now on Telegram. Click here to join our channel (@indianexpress) and stay updated with the latest headlines

For all the latest Explained News, download Indian Express App.

IE Online Media Services Pvt Ltd

View original post here:

What we know of Covid-19 now: Updated symptoms, modes of transmission, immunity and complications - The Indian Express