Lower Respiratory Tract Infections

What type of virus is the Influenza Virus classified as?

Orthomyxovirus.

How must the Influenza Virus genome be processed to produce more virus?

It must be transcribed from RNA genome into mRNA.

What is a major limitation of host cells regarding the Influenza Virus?

Cells cannot make RNA from RNA.

What enzyme do viruses package within their capsid to assist with transcription?

An RNA-dependent RNA polymerase.

Which strains of the Influenza Virus affect humans?

Strain A, B, and C.

What factors are included in the classification of Influenza Virus?

Place and date of isolation, N & H antigen types, and animal host.

What does HA stand for in the context of the Influenza Virus?

Hemagglutinin, a viral attachment and fusion protein.

What role does NA play in the Influenza Virus lifecycle?

Neuraminidase cleaves sialic acid and promotes virus release after budding.

How many HA subtypes have been found in Influenza A Viruses isolated from aquatic birds?

16 HA subtypes (H1-H16).

How are Influenza Viruses primarily transmitted?

By respiratory droplets or contact.

How long can the Influenza Virus survive on surfaces?

24 hours.

What is the incubation period for uncomplicated Influenza?

1-5 days.

What are common symptoms of Influenza upon onset?

Headache, chills, dry cough, high fever, myalgias, malaise, anorexia.

When does fever typically peak after Influenza infection?

Within the first 24 hours.

What type of Influenza vaccine is a flu shot made from?

Inactivated (killed) whole virus of the most common strains.

What is FluMist?

A live attenuated virus containing three different H & N proteins.

Why is vaccination important during flu season?

To produce high levels of circulating antibodies.

What is tuberculosis often referred to as?

Consumption.

What are some symptoms of tuberculosis?

Coughing, pallor, fluid in lungs, coughing of blood.

How many people are currently infected with tuberculosis worldwide?

Approximately 2 billion.

What bacteria causes tuberculosis?

Mycobacterium tuberculosis.

What immune response leads to the formation of tubercles in tuberculosis?

Cell-mediated immune response.

What does the Mantoux test indicate for tuberculosis?

A small red bump for negative, a large red swollen bump for positive.

What is the BCG Vaccine based on?

A weakened Bovine Strain.

What is a concern regarding the BCG Vaccine's efficacy?

It depends on vaccine variation and geography.

Why is the BCG vaccine not used in the US?

It can cause skin test conversion, complicating screening.

What is a key challenge in tuberculosis treatment related to public health?

Deterioration of public health facilities.

What are some factors that influence the progression of tuberculosis infection?

Socioeconomic status, malnutrition, immune status, and number of mycobacteria.

What are the new vaccines for tuberculosis currently being tested for?

To be used alone or in conjunction with BCG.