Influenza A virus subtype H3N2

 Introduction

Influenza A virus subtype H3N2, also known as the Hong Kong flu, is a type of influenza virus that infects humans and causes respiratory illness. The virus is highly contagious and can spread rapidly in crowded places such as schools, nursing homes, and airports. In this blog, we will discuss the characteristics, symptoms, transmission, diagnosis, treatment, and prevention of influenza A virus subtype H3N2.

Characteristics

Influenza A virus subtype H3N2 belongs to the family Orthomyxoviridae, which is a group of viruses that cause respiratory illness. The virus has an RNA genome that is segmented, meaning that it is divided into eight separate pieces of genetic material. This allows the virus to easily recombine with other influenza viruses, leading to the emergence of new strains. H3N2 virus has a spherical shape with a diameter of approximately 80-120 nanometers.

Symptoms

The symptoms of influenza A virus subtype H3N2 are similar to those of other types of influenza. They include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills, and fatigue. In some cases, vomiting and diarrhea may also occur, especially in children. The symptoms usually appear within two to four days after exposure to the virus and can last for up to a week.

Transmission

Influenza A virus subtype H3N2 is highly contagious and can spread easily from person to person through respiratory droplets when an infected person coughs, sneezes, or talks. The virus can also be spread by touching surfaces contaminated with the virus and then touching one's mouth, nose, or eyes. The virus can survive on surfaces for up to 48 hours.

Diagnosis

The diagnosis of influenza A virus subtype H3N2 is usually based on clinical symptoms and laboratory tests. A healthcare provider may perform a rapid influenza diagnostic test (RIDT), which involves swabbing the back of the throat or nose and testing the sample for the presence of the virus. However, the RIDT has a high rate of false negatives and false positives, and a negative result does not necessarily rule out the possibility of infection. A more accurate test is the reverse transcription-polymerase chain reaction (RT-PCR) test, which detects the genetic material of the virus.

Treatment

The treatment of influenza A virus subtype H3N2 usually involves antiviral medications such as oseltamivir (Tamiflu) or zanamivir (Relenza). These medications can help to reduce the severity and duration of symptoms if taken within the first 48 hours of symptom onset. However, they are less effective if taken later. Over-the-counter medications such as acetaminophen and ibuprofen can also help to relieve symptoms such as fever and body aches. Rest and hydration are also important for recovery.

Prevention

The best way to prevent influenza A virus subtype H3N2 is to get vaccinated. The influenza vaccine is usually updated each year to protect against the strains that are most likely to circulate during the upcoming flu season. The vaccine is recommended for everyone over the age of six months, especially those who are at high risk of complications from influenza, such as young children, older adults, pregnant women, and people with underlying medical conditions. Other preventive measures include washing hands frequently with soap and water, covering the mouth and nose when coughing or sneezing, avoiding close contact with sick people, and staying home when sick.

Conclusion

Influenza A virus subtype H3N2 is a highly contagious virus that can cause respiratory illness in humans. The symptoms are similar to those of other types of influenza and can be severe in some cases.