Human Rhinoviruses and the Common Cold

Definition: Human rhinoviruses (HRVs) are a type of picornavirus that causes the common cold.
Transmission: HRVs are highly contagious and spread through:
- Direct contact with contaminated surfaces or objects
- Airborne transmission through coughing and sneezing
- Close contact with an infected person
Pathogenesis: HRVs infect the epithelial cells of the upper respiratory tract, causing inflammation and symptoms such as:
- Runny nose
- Sneezing
- Coughing
- Sore throat
- Fatigue
Immune Response: HRVs are highly antigenically variable, making it difficult for the immune system to mount a effective response. However, the immune system can produce neutralizing antibodies against specific HRV serotypes.

Definition: Influenza, commonly known as the flu, is a contagious respiratory illness caused by the influenza virus.
Types: There are three main types of influenza viruses:
- A: affects humans and animals, and is responsible for seasonal outbreaks and pandemics
- B: affects humans and is responsible for seasonal outbreaks
- C: affects humans and is responsible for mild infections
Transmission: Influenza viruses are transmitted through:
- Airborne transmission through coughing and sneezing
- Close contact with an infected person
Pathogenesis: Influenza viruses infect the epithelial cells of the respiratory tract, causing inflammation and symptoms such as:
- Fever
- Cough
- Sore throat
- Runny or stuffy nose
- Headache
- Fatigue
Immune Response: The immune system produces antibodies against influenza viruses, which can provide protection against future infections. However, the immune system must constantly adapt to new strains of the virus through vaccination or natural infection.

Definition: Varicella-zoster virus (VZV) is a herpesvirus that causes two distinct diseases:
- Chickenpox (varicella): a primary infection characterized by a rash and fever
- Shingles (zoster): a reactivation of the virus in adults, characterized by a painful rash
Transmission: VZV is transmitted through:
- Direct contact with an infected person
- Airborne transmission through coughing and sneezing
Pathogenesis: VZV infects the skin and nervous system, causing symptoms such as:
- Rash
- Fever
- Headache
- Fatigue
- Painful rash (shingles)
Immune Response: The immune system produces antibodies against VZV, which can provide lifelong protection against future infections. However, the virus can reactivate in adults, causing shingles.

Definition: Rev is a protein encoded by the human immunodeficiency virus (HIV) that plays a crucial role in viral replication.
Function: Rev regulates the expression of HIV genes by:
- Binding to RNA and promoting its export from the nucleus to the cytoplasm
- Inhibiting the production of RNA that inhibits viral replication
Importance: Rev is essential for HIV replication and is a key target for antiretroviral therapy.

Definition: Adenoviruses are a type of DNA virus that causes a range of diseases, including:
- Respiratory infections
- Gastroenteritis
- Conjunctivitis
Transmission: Adenoviruses are transmitted through:
- Direct contact with contaminated surfaces or objects
- Airborne transmission through coughing and sneezing
- Fecal-oral transmission
Pathogenesis: Adenoviruses infect the epithelial cells of various tissues, causing symptoms such as:
- Fever
- Cough
- Sore throat
- Diarrhea
- Vomiting
Immune Response: The immune system produces antibodies against adenoviruses, which can provide protection against future infections. However, the immune system must constantly adapt to new strains of the virus through vaccination or natural infection.

HRVs cause the common cold and are highly contagious
Transmission occurs through direct contact, airborne transmission, and close contact with an infected person
HRVs infect epithelial cells of the upper respiratory tract, causing inflammation and symptoms like runny nose, sneezing, coughing, sore throat, and fatigue
The immune system produces neutralizing antibodies against specific HRV serotypes, but HRVs are highly antigenically variable, making immunity difficult

Influenza is a contagious respiratory illness caused by the influenza virus
There are three main types: A (affects humans and animals, responsible for seasonal outbreaks and pandemics), B (affects humans, responsible for seasonal outbreaks), and C (affects humans, responsible for mild infections)
Transmission occurs through airborne transmission and close contact with an infected person
Influenza viruses infect epithelial cells of the respiratory tract, causing inflammation and symptoms like fever, cough, sore throat, runny or stuffy nose, headache, and fatigue
The immune system produces antibodies against influenza viruses, providing protection against future infections, but must constantly adapt to new strains through vaccination or natural infection

VZV causes two distinct diseases: chickenpox (varicella) and shingles (zoster)
Transmission occurs through direct contact and airborne transmission
VZV infects the skin and nervous system, causing symptoms like rash, fever, headache, and fatigue, and a painful rash in shingles
The immune system produces antibodies against VZV, providing lifelong protection against future infections, but the virus can reactivate in adults, causing shingles

Rev is a protein encoded by HIV that regulates the expression of HIV genes
Rev binds to RNA, promoting its export from the nucleus to the cytoplasm and inhibiting the production of RNA that inhibits viral replication
Rev is essential for HIV replication and is a key target for antiretroviral therapy

Adenoviruses cause a range of diseases, including respiratory infections, gastroenteritis, and conjunctivitis
Transmission occurs through direct contact, airborne transmission, and fecal-oral transmission
Adenoviruses infect epithelial cells of various tissues, causing symptoms like fever, cough, sore throat, diarrhea, and vomiting
The immune system produces antibodies against adenoviruses, providing protection against future infections, but must constantly adapt to new strains through vaccination or natural infection