Influenza

Happy flu season! I’ve just been stuck inside for 5 days with a mild case, so this is a bit bitter

There are 3–5 million cases of flu per year, and ~375,000 deaths, usually in older, younger, and immunocompromised individuals.

Enveloped, Single-stranded RNA virus

First identified in 1933, but existed long before

Generally considered an infection of the bronchi

so effectively a form of bronchitis – i.e. it causes inflammation of the bronchi

There are 3 types - A, B and C

B & C appear restricted to humans

C is less common

A is found in wide range of species including pigs and poultry as well as man

Type A appears to be responsible for more severe disease

Basics

Transmission by aerosols

Incubation ~2 days

Contagious during first 3-5days of illness

Symptoms – fever, myalgia, headache, dry cough, sore throat, aches, fatigue

Recovery ~7-10 days for most

Complications – most frequent = secondary bacterial pneumonia, rarely = viral pneumonia, myocarditis, encephalitis

No specific treatment

Vaccination for high risk groups including the elderly, health care workers, those with underlying respiratory conditions.

Avian

The main reservoir is wildfowl that are resistant to the disease

doesn’t usually affect animals other than poultry and pigs

However some transfer events occur

Seasonal

Incidence highest in winter

Strains vary from year to year - hard to predict and vaccinate (this year’s vaccine has been pretty rubbish)

Pandemic

Can be caused by any strain that has not been seen in the human population for many years

New strains evade the herd immunity that exists to previously encountered strains

1918 /19 –( Spanish) estimated 40-50 million deaths worldwide

1957 – Influenza A/H1N1 (Asian)

1968 – Influenza A/H3N2 (Hong Kong)

Eventually the virus runs out of susceptible hosts and the epidemic fizzles out

Experts generally agree another pandemic is inevitable, and may be imminent – maybe we have had some minor pandemics

16000 confirmed H1N1 deaths in 2009 affecting over 200 countries

Consensus is that the prompt action of the Hong Kong authorities probably prevented a pandemic in 1997

The prediction is scary - for industrialised countries they predic 1.0 – 2.3 million hospitalisations

280,000-650,000 deaths

in two years

A network of 112 centres monitor flu isolates to identify unusual strains that can then be examined further

The WHO has a Pandemic Preparedness Plan in place http://www.who.int/influenza/preparedness/pandemic/en/

Diagnosis

Generally based on GP diagnosis

Virus isolation / virus demonstration from nasopharyngeal secretions during acute phase

Demonstration of viral antigen in secretions

Antibody rise using paired sera ( 1st sample taken between days 1-3 of illness, 2nd taken around day 12 of illness) by haemagglutination inhibition or complement fixation test

Molecular methods evolving rapidly – in particular in response to the recent epidemic/pandemic strains emerging

A range of respiratory illnesses have the same symptoms, only laboratory testing can confirm the aetiological agent

Treatment/Vaccination

In the UK NICE argue that immunisation against predicted strains is the best form of defence – traditionally focused on the elderly and those with underlying lung problems, but recently started rolling out a childhood vaccine (nasal spray)

Vaccines generally based on the H & N surface structures which mutate, however hopes of an M protein based vaccine which will give longer lasting protection raised recently

Antivirals

Antivirals not recommended in otherwise healthy people (amantadine should not be used at all) - should ride it out

However when incidence reaches a certain level zanamivir and oseltamivir should be used in those considered high risk for the development of complications – PROVIDED THAT TREATMENT IS STARTED WITHIN 48 HOURS OF ONSET OF SYMPTOMS

Resistance is becoming an issue

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Flashcards with quizlet!

For more: instagram: https://www.instagram.com/studydiaryofamedstudent/

Some general resources:

Chemistry Glossary

Chemistry Exam Survival Guide

Toolbox – interactive graphing, tables, and calculators

Make virtual chemistry models

Interactive periodic table

Another site for making virtual chemistry models

Virtual labs – covers stoichiometry, thermochemistry, eq1uilibrium, acid base chemistry, solubility, oxidation/reduction and electrochemistry, analytical chemistry/lab techniques

Concept tests

Chemistry Science Fair Project Ideas

OChem Reaction Bank

Interactive chem simulations

Chemical calculations

The Chem Blog

Molecule of the day

Free chemistry drawing software

Laboratory Safety - Laboratory safety for the chemistry classroom

Periodic Table of Videos - Brady Haran

On this day in chemistry… - a history of chemistry

The faces of chemistry

Experimentation hub - explore and enjoy our experiments to increase engagement in scientific investigation, develop new skills and enhance your knowledge.

Understanding journals - including reading articles, referencing, and example articles.

Resources for specific topics:

Stochiometry – the mole, molarity and density, reaction stoichiometry and limiting reagents, empirical formula and mixtures, gravimetric analysis

Themochemistry – energy and enthalpy, entropy

Kinetics – phenomenological and mechanistic kinetics

Equilibrium – LeChatlier’s principle, progress of reaction, equilibrium calculations, common ion effect

Acid base chemistry – strong acid and bases, weak acids and bases, buffer solutions, acid/base titrations

Solubility – solubility product, solubility and PH, common ion effect

Oxidation/Reduction and Electrochemistry – standard reduction potentials, galvanic cells

Analytical chemistry/ Lab techniques – reaction stoichiometry and limiting reagents, acid/base titrations, redox titrations, gravimetric analysis, UC/Vis spectroscopy

Physical chemistry – quantum mechanics, spectroscopy

Properties of solutions – intermolecular forces, colligative properties

Textbooks:

Chemistry Virtual Textbooks, Stephen Lower

Organic Chemistry, Tim Soderberg

Organic Chemistry I, George Mhehe

Environmental Chemistry, Dejene Tessema

Virtual Organic Chemistry

Industrial Chemistry, Helen Njenga

Inorganic Chemistry, Chrispin Kowenje

Physical Chemistry I, Onesmus Munyaki

General Chemistry, Principles, Patterns and Applications

Chemistry Books - a variety of chemistry textbooks

Chemistry Tutorials/Guides:

Atoms, Molecules, and Ions

Chemical reactions and stoichiometry

Electronic structure of atoms

Periodic table

Chemical bonds

Gases and kinetic molecular theory

State of matter and intermolecular forces

Chemical equilibrium

Acids and bases

Acid base equilibria and solubility equilibria

Thermodynamics

Redox reactions and electrochemistry

Kinetics

Nuclear chemistry

Organic Chemistry Tutorials/Guidelines:

Structure and bonding

Dot structures

Hybridization

Bond-line structures

Electronegativity

Resonance and acid base chemistry

Counting electrons

Resonance structures

Organic acid-base chemistry

Alkanes, cycloalkanes and functional groups

Naming alkanes

Naming alkanes, cycloalkanes, and bicyclic compounds

Conformations of alkanes

Conformations of cycloalkanes

Functional groups

Stereochemistry

Chirality

Enantiomers

Stereoisomeric relationships

Subsituation and elimination reactions

Free radical reaction

Sn1 vs Sn2

Nucleophilicity and basicity

Elimination reactions

Sn1/Sn2/E1/E2

Sn1 and Sn2

Alkenes and alkynes

Naming alkenes

Alkene reactions

Alkene nomenclature

Alkene reactions

Naming and preparing alkynes

Alkyne reactions

Alcohols, ethers, epoxides, sulphides

Alcohol nomenclature and properties

Synthesis of alcohols

Reactions of alcohols

Nomenclature and properties of ethers

Synthesis and cleavage of ethers

Nomenclature and preparation of epoxides

Conjugation, Diels-Alder, and MO theory

Addition reactions of conjugated dienes

Diels-Alder reaction

Molecular orbital theory

Aromatic compounds

Naming benzene derivatives

Reactions of benzene

Aromatic stability

Electrophilic aromatic substitution

Directing effects

Other reactions and synthesis

Aldehydes and ketones

Introduction to aldehydes and ketones

Reactions of aldehydes and ketones

Carboxylic acids and derivatives

Naming carboxylic acids

Formation of carboxylic acid derivatives

Nomenclature and reactions of carboxylic acids

Nomenclature and reactions of carboxylic acid derivatives

Alpha carbon chemistry

Formation of enolate anions

Aldol condensations

Amines

Naming amines

Spectroscopy

Infrared Spectroscopy

UV/Vis Spectroscopy

proton NMR

Careers:

A future in Chemistry

What can I do with my chemistry degree?

Chemistry Careers - American Chemical Society

What to do with a degree in chemistry - The Guardian

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Another Harry Potter Mnemonic (yayyy!!!)

So, whenever I read about this fungi Sporothrix schenckii I think about Bellatrix Lestrange… geti it?

Sporothrix - Bellatrix

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Ok, enough with the Harry Potter fact.

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