As India grapples with a severe H3N2 outbreak, a spike in adenovirus cases across Indian states, particularly in West Bengal, has led to a double whammy, or rather, a triple whammy if one were to consider an increase in Covid-19 infections. A subtype of influenza A strain is driving a surge in H3N2 cases in India, with three deaths reported so far and a total of 451 cases as of March 5. Meanwhile, the adenovirus outbreak in Bengal is more lethal—19 children have died so far and several are hospitalised, with some even admitted to the ICU. With 524 fresh Covid cases also being reported, the Indian Medical Association has sprung into action with task forces on standby.
“Adenovirus is far more virulent and lethal than H3N2 and Covid,” says Dr Rashmi Khadapkar, senior research scientist at SRL Diagnostics. “The current strain is more virulent in children and the mortality rate is between 20-50 per cent. Out of 100+ strains of adenovirus, 6 types are known to cause more serious infections and even lead to death. They are types 3, 4, 7, 8, 14 and 55,” she says. As per reports, adenovirus type 3 and 7 are behind the surge in infections in Bengal. “Type 14 is the most lethal one but as of now, type 3 and 7 are driving the surge in infections in India,” she adds.
Moneycontrol spoke to infectious disease experts across the country to know from them how one can differentiate between Adenovirus, H3N2 and Covid-19 infections.
Symptoms: The differentiating factor
While fever, runny nose, and fatigue are common symptoms in all three, Dr Umang Agrawal, consultant, Infectious Diseases, at P D Hinduja Hospital, says those infected with adenovirus are likely to have conjunctivitis. The redness of eyes, irritation and watery eyes are more common in adenovirus. “If the patient has high fever for a longer period of time, along with conjunctivitis, it’s likely to be adenovirus. Presence of lymph nodes is another symptom that can be used to confirm the diagnosis.”
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
For H3N2 however, the differentiating symptom is high fever accompanied with a painful cough that develops into bronchitis, says Dr Vasant Nagvekar, co-director, Infectious Diseases, Sir HN Reliance Foundation Hospital. “In case of H3N2, even when the high-grade fever subsides, patients still complain of a bad cough. In Covid, the nasal secretion, loss of taste and smell are more common.”
To sum it up, Dr Nagvekar breaks down the differentiating symptoms as follows:
Covid: Mild, self-limiting fever that lasts for a short while accompanied by nasal secretion and a loss of taste and smell
H3N2: High-grade fever which eventually develops into a painful cough that lasts weeks and develops into bronchitis
Adenovirus: High-grade fever that lasts for 7 days, can go up to 10 of even 14 days, often accompanied with conjunctivitis
Prognosis: The road to recovery
How does the treatment differ for the 3 viruses? The general consensus among the medical community regarding viral infections is to take rest and have plenty of fluids. “Our immunity is our first line of defense when it comes to viral infections. From a prognosis point of view, steam inhalation, monitoring your fever and keeping yourself hydrated are all ways you can relieve your symptoms. There is no special line of treatment unless symptoms get worse and one has to get hospitalised,” says Dr Khadapkar. Adding to this, Dr Agrawal says “The 3 viruses are different but their baseline treatment is the same. The treatment is different only when the patient is hospitalised, in which case the doctor will prescribe specific anti-virals which are different for the 3 viruses.”
Warning Signs: When to Seek Help
Back in the first wave of Covid, those who tested positive were given oximeters to monitor their oxygen saturation levels and were advised to visit the emergency room if the levels dropped below 94 per cent. What are the warning signs one should look out for in case of these 3 viruses? Dr Nagvekar breaks it down as follows:
For H3N2 and Covid: Excessive coughing, breathlessness and low oxygen saturation are all warning signs one should look out for. Visit your doctor or emergency room if these symptoms persist.
For Adenovirus: Excessive fever and severe respiratory distress should be enough to ring an alarm in this case. Consider seeking medical help if these symptoms last for a long time
Precautions: Keeping virus at bay
Despite multiple viral outbreaks across the country, Dr Nagvekar advises against the use of immunity boosters and immunity boosting pills. Instead, he stresses on following standard practices such as eating and hydrating well and getting an adequate amount of rest, which will help keep the infection at bay. Dr Agrawal stresses on the importance of vaccination. “I cannot stress enough on the importance of getting vaccinated. It is heartbreaking to see children lose their lives over a vaccine-preventable disease. No tonic or immunity boosting food will keep you safe like a vaccine dose can.” Dr Nagvekar, meanwhile, recommends going for low-fat and low-spice food while maintaining a healthy eating regime during the flu season.